Dynamometer Results & Comparisons - 528HP 491TQ.... BUT have you ever seen a graph like this!?!

Well i put down 528HP and 491TQ on 14psi, 11.5afr, 22*

BUT the darn car pulls HARD to 5500-5600 then drops to NOTHING! It woud put down ALOT better numbers if it would pull past 5500rpm....

Also on the dyno graph the tq and hp stay almost the same instead of the tq slowly dropping when they cross.... kind of crazy! Never seen a dyno graph like this..... not sure what is wrong.

Springs are good, plugs are tr8's, no KR, not sure what the problem is!!!!!!

ANY ideas??????

http://i721.photobucket.com/albums/ww216/one_bad_ls1/FM53T70dynoday016.jpg

http://s721.photobucket.com/albums/ww216/one_bad_ls1/?action=view&current=FM53T70dynoday014.flv

looks like you have a boost leak, my brothers supra was doing the samething, graph looked the same as well, ended up have two boost leaks.

still some damn good numbers tho!

still some damn good numbers tho!

Thanks,

ya on my log it doesn't show a boost leak to drop the HP like that i dont think.....

I attached the tune and a log file....

V-A-L-V-E-F-L-O-A-T

Your valve is doing this....:gruffy:....when its suppose to be seated shut on the back on the valve seat and making compression on the next power stroke.

You need STOUT springs and lighter weight valvetrain components on boosted apps because the intake valve is trying to be blown open by the pressurized inlet tract. You could see 30 lbs or more less seat pressure due to this.

You need 165 on the seat minimum and over 400 open.....heavy rockers are no good....lighter valves are good if possible (on the intake side).

That or somehow your blowing out the spark....you could try reducing your plug gap some.....but my guess is valvefloat.

Take the blower belt off and see how much RPM it will turn cleanly....thats a good test to see if boost and not enough spring pressure is the culprit.

-Tony

EDIT: Looks too dramatic a decline for boost leak....you would have similar boost 200 RPM's before it takes a dump and the graph looks solid. Speaking of that I wanted to congratulate you on what looks to be a beastly combo if you can sort out your higher RPM issues. There could be another 100 HP in this easily based on that curve.....actually make that 150....LOL

well its weird that we put 2 shims in the turbo xs rfl bov and picked up 30 to the wheels, boost leak at the bov still? its sealed a lot better tho! we re-shimmed it.

tonys right on the valve float, but i call bs beings you have prc duals.....

maybe your next thing is to shim the bov on the dyno. you need to test that thing seperate, with a separate tube and either a pressurized source or vacuum.

maybe its still on the bov?

well its weird that we put 2 shims in the turbo xs rfl bov and picked up 30 to the wheels, boost leak at the bov still? its sealed a lot better tho! we re-shimmed it.

tonys right on the valve float, but i call bs beings you have prc duals.....

maybe your next thing is to shim the bov on the dyno. you need to test that thing seperate, with a separate tube and either a pressurized source or vacuum.

maybe its still on the bov?
Actually the BOV failing is possible but once again it seems really aggressive and even if it just completely gave up the ghost would power drop to even horrible N/A levels that abruptly.....I guess potentially because the blower is spinning robbing a bunch of power. I didn't even open any of the run logs....is it still making any boost when the curve is falling off a cliff?

Also, a standard PRC spring set up improperly (too tall) could certainly be a problem....I would hope he had the PRC upgrade springs like our 8019 versions (the "extreme" version I believe they call them).

I'm certainly very curious what it ultimately turns out to be....I will be watching this thread seeing how things pan out, not to mention how much power this thing lays down when it is sorted out..

-Tony

Aren't there a number of guys out there who boost bone stock long blocks without valve float? I think so.... Are you maintaining fuel pressure the entire pull? Boost steady the entire time? What did you gap your plugs to? Are you running the car in speed density? or blow through MAF?

check your cut on your cam my car did the same exact thing turns out comp cut the cam wrong

Actually the BOV failing is possible but once again it seems really aggressive and even if it just completely gave up the ghost would power drop to even horrible N/A levels that abruptly.....I guess potentially because the blower is spinning robbing a bunch of power. I didn't even open any of the run logs....is it still making any boost when the curve is falling off a cliff?

Also, a standard PRC spring set up improperly (too tall) could certainly be a problem....I would hope he had the PRC upgrade springs like our 8019 versions (the "extreme" version I believe they call them).

I'm certainly very curious what it ultimately turns out to be....I will be watching this thread seeing how things pan out, not to mention how much power this thing lays down when it is sorted out..

-Tony

ya the boost is there through the whole pull.... i am gonna try some tr7's and some msd plugs....

I have the PRC dual springs good to .660 with titanium retainers.... they should be good... I would think. I can wait till i figure out the problem... its fast now but man if it pulled all the way through, i should be able to make a 10sec pass pretty easy next spring!

Aren't there a number of guys out there who boost bone stock long blocks without valve float? I think so.... Are you maintaining fuel pressure the entire pull? Boost steady the entire time? What did you gap your plugs to? Are you running the car in speed density? or blow through MAF?

well my afr is staying fine... so the pressure should be good, but i have a second walbro i need to get installed this weekend.

Boost fluctuates a few kpa throughout the pull (logs)

ya it an SD tune.

plugs are gapped at 22, and are tr8's (maybee to cold????)

check your cut on your cam my car did the same exact thing turns out comp cut the cam wrong

Im running a stock 02 Z06 cam.....

Listen to Tony Mamo... Listen to Tony Mamo... Listen to Tony Mamo...

Shane

i dont think it could be valve float because i had brand new patriot spings and all that other stuff and both on 5psi and 10psi when i had my turbo dropped off like that also ....no boost leaks nothing wrong but the car still pulled like a SOB past 5k where it started to drop off

i cant open any of your log files (still working on this hpt thing...)

but whoever is skilled should check them out. you can clearly see in the log file where the motor 'revs slower' past 5300. it climbs hard then levels off, you can also notice it in the movie clips, just where the car climbs to 5300 fast then takes forever to get to 6400.

i would still check for boost leaks, i dont know of anything "showing" boost leaks. best thing to do is shoot compressed air through out the intercoolerpiping, anything that holds boost. maybe leaking wastegate?

Didn't read any replies, but that's valve float.

I would wager you have stock or LS6 valve springs too, though you should not.

If this is an STS car it may just be choking up top as they all do from too tight of an A/R, but it sure LOOKS like all of the valve float that I have seen.

If it ain't valve float, it's blowin out the spark. What's the plug gap? Did you crank up the coil dwell any?

Too small of a Turbo will do that.

Without seeing the car it's just guess work.

one of 2 things...
valve float "doubting this with the duals"
ore your blowing out the spark....im leaning towards this thats a cool ass plug id throw a 7 range plug in it gapped around .028-.030 and see what happens....

i used to fool with turbo dsm's and put together a couple of turbo 2.3 fox bodies...and im leaning towards blowing out the flame....
to many bossted cars with stock or ls6 springs....doing just fine....

your build is similar to what im doing except im using ported heads and a mp gt45...

nice numbers regardless man...the 5.3s are amazing

whats going on with your kpa values? 85kpa under boost?

Are you clutch or a4..wonder if it could be slipping clutch or slipping auto trans? Would think it should pull to 6500 or so.

Are you clutch or a4..wonder if it could be slipping clutch or slipping auto trans? Would think it should pull to 6500 or so.

its an auto and it is slipping a little but not that much, mainly right after it shifts and it doesn't shift on the dyno....

whats going on with your kpa values? 85kpa under boost?

I guess im not understanding your question..... ?????

my KPA values will be a little different because i am running 317 heads at around 8.5 compression..... not stock heads and compression

What is the turbo rated for airflow max?

If it ain't valve float, it's blowin out the spark. What's the plug gap? Did you crank up the coil dwell any?


no i didn't mess with coil dwell.....

I am gonna try switching to tr7's tomorrow and see how it runs (on the street, cant afford to dyno again for a while)

MSD pug wires should be here soon also...

I think you have to delete your map sae pid in your scanner and insert 2bar map. You need to delete normal maf sae pid and map sae pid.

So does i sound like its breaking up at the higher rpms..??normal tr8 might foul out in normal driving. any machine gun or other misfiring noise..
I think tr7 will be lots or tr7ix .You can run the iridiums colder heat ranges without fouling. .028 to .030 should fire that boost level pretty easily if things are ok with your coils and wire and the plugs are not fouling out. Have you looked at any of the tr8s?
I was planning to go to tr8ix in my car next year if go to around 15psi or so max. Been running autolite 103 at .028 no problems and many run them to high boost like 15,18 ,they also don't foul out that easy.
Too cold might be your problem.

I think you have to delete your map sae pid in your scanner and insert 2bar map. You need to delete normal maf sae pid and map sae pid.

So does i sound like its breaking up at the higher rpms..??normal tr8 might foul out in normal driving. any machine gun or other misfiring noise..
I think tr7 will be lots or tr7ix .You can run the iridiums colder heat ranges without fouling. .028 to .030 should fire that boost level pretty easily if things are ok with your coils and wire and the plugs are not fouling out. Have you looked at any of the tr8s?
I was planning to go to tr8ix in my car next year if go to around 15psi or so max. Been running autolite 103 at .028 no problems and many run them to high boost like 15,18 ,they also don't foul out that easy.
Too cold might be your problem.

ya with the PID thing... my pcm is the shitty 98 so i have to do it a little different. but i am loggin all the way up to 210kpa... not sure what he's getting at with the 85kpa deal, im confused lol.

i mean yes i can hear a difference in the motor in the upper rpms but not
real bad... i can deffinetly feel a difference in the pull though.

i will be able to tell if its the plugs when i pull them tomorrow and install the 7's.

Its just the way it is set up. in log hpl 4 you kpa values are different in from your chart display and your table display. I was reading your chart display values which say 85kpa but in your table its 170's... I think its just the way its setup

Its just the way it is set up. in log hpl 4 you kpa values are different in from your chart display and your table display. I was reading your chart display values which say 85kpa but in your table its 170's... I think its just the way its setup

thats wierd.... my computer is showing the same on the chart and table....

IDK, someone else check the log file and see if they match up.....

ive not looked at the file..no hpt on my desktop ill load it in a bit though....im assuming you are using the 2 bar custom os....and it didnt fry your pcm....im wanting to upgrade to it but have heard mixed reviews...haha

http://i721.photobucket.com/albums/ww216/one_bad_ls1/FM53T70dynoday016.jpg

3000 - 43KPA, 47*, 1.00 lambda, IAT 66
3200 - 88KPA, 33*, 1.02 lambda, IAT 66
3500 - 91KPA, 32*, 0.91 lambda, IAT 66
4000 - 97KPA, 28*, 0.87 lambda, IAT 66
4300 - 101KPA, 26*, 0.86 lambda, IAT 66
4500 - 110KPA, 22*, 0.78 lambda, IAT 66

4600 - 120KPA, 22*, 0.78 lambda, IAT 66
5000 - 146KPA, 22*, 0.75 lamdba, IAT 66
5200 - 160KPA, 22*, 0.75 lambda, IAT 66
5400 - 171KPA, 22*, 0.75 lambda, IAT 66
5500 - 167KPA, 22*, 0.77 lambda, IAT 66
5600 - 179KPA, 22*, 0.78 lambda, IAT 66
5700 - 177KPA, 21*, 0.78 lambda, IAT 68
5800 - 176KPA, 21*, 0.77 lambda, IAT 72
5900 - 179KPA, 21*, 0.76 lambda, IAT 73
6000 - 175KPA, 21*, 0.76 lambda, IAT 75
6100 - 171KPA, 21*, 0.75 lambda, IAT 79
6200 - 164KPA, 21*, 0.75 lambda, IAT 81
6300 - 157KPA, 21*, 0.74 lambda, IAT 81
6400 - 174KPA, 21*, 0.74 lambda, IAT 84

IDK, figured i would write everything out so it was easier to compare to the dyno graph...... instead of off the log file....

I got the second walbro set in today.... I still have to wire the hobbs pressure switch and relay.

My MSD plugs also showed up today and i went and bought some autolite 103's.....

I will try to get everything installed and see if fixes it tomorrow....

had a ta witrh similar graph showed no kr on dyno but did with a predator hand held changed knock sensors picked up 60 horse on dyno .

whats your trim on your turbo it migh be the right volume or size but not making optimum but past 5500 rpms might need a higher trim number

had a ta witrh similar graph showed no kr on dyno but did with a predator hand held changed knock sensors picked up 60 horse on dyno .

I logged the runs in HPtuners and nothing shows up for KR, I am aslo getting my commanded timing during the run....

whats your trim on your turbo it migh be the right volume or size but not making optimum but past 5500 rpms might need a higher trim number

Master Power T70/.96AR, should be good for more than 530hp on a 5.3 I would think

What are the comments about the post #5 from Tony Mamo???

Christian

way too small of a turbo.

USually peaks around low 500ish.

way too small of a turbo.

USually peaks around low 500ish.

I thought the MP t70 would make more than 500hp... and though it would push a reliably up to 16psi.

Hmm thought read they could do low 600s rwhp.And why can't you also run it higher boost like 18 to 20psi?

Be curious to see if the plugs and wires help the problem.

Hmm thought read they could do low 600s rwhp.And why can't you also run it higher boost like 18 to 20psi?

Be curious to see if the plugs and wires help the problem.

i also heard low 600's.... i think i read somewhere that anything above 16psi on the MPT70 wouldn't be reliable boost.... maybee it was some BS, not sure.

I guess it really depends on the setup though....

I am doing the plugs wires and second walbro right now.... i have to keep coming inside to warm up! Its F***ing cold outside!

Ok guys i had something else come to mind today...

I used 7.425 pushrods on my setup because of the 02 Z06 cam (it has a smaller base circle).... well it works fine for people with 241 and 243 heads.... but i am running the 317 heads.

With the 317 heads do i need to run an even longer rod? I have a set of 7.45 rods from my cam only setup i had.


I do have quite a bit of valvetrain noise, actually just about as much as the 227/231 .614 .617 112+2 cam did.

What do you guys think? Could that be a problem? I just assumed the 7.425 rods were right, but maybee they are just to short??????

Thanks,

Blaine

PS I know get a pushrod length checker, lol, I just figured i would get opinions befor i went and purchased one and went through the trouble....

you know what you get when you assume? you make an ass out of you....and well you only i guess
pushrod checker and measure man...may have missed...what lifters, stock rockers?

oh and dont listen to these crazy's who are telling you than you have insuffiencent spring...people running 13lbs of boost on stock ls6 longblocks 02z cam and ls6 springs...the springs you have, have way more pressure open and closed

Just install some truck coils! That should solve your problem!

You can pick a set up from any of the vendors on the site who keep them stockpiled in a shed out back, marked up only 30% from the price they paid at the junkyard!

How did you install the cam? Straight up dot to dot? Or did you degree it?

How did you install the cam? Straight up dot to dot? Or did you degree it?

dot to dot

even if the cam is off a little it wouldn't make the graph like that would it?

even if the cam is off a little it wouldn't make the graph like that would it?

Valve float would...

I have prc dual... don't think its the prob... but starting to wonder

oh and dont listen to these crazy's who are telling you than you have insuffiencent spring...people running 13lbs of boost on stock ls6 longblocks 02z cam and ls6 springs...the springs you have, have way more pressure open and closed
That is terrible info right there. You have MUCH more stress on the valvetrain on a boosted setup. Air is forced into the chamber rather than drawn in as in an NA setup. So everytime the valve tries to close the pressure in the system is trying to force it open. Im not saying his problem is springs but if you've hung around the Forced Induction section bad/weak springs have been ALOT of peoples problems, especially those with stock springs.

so I suppose these countless 575rwhp+ stock ls6 cam and spring FI guys are lying...chode...hes running a stock LS6 cam with non stock springs

Since when does a Z06 cam require longer than stock pushrods? 7.4 should do it but with the head swap then it just becomes a guessing game unless you measure.

so I suppose these countless 575rwhp+ stock ls6 cam and spring FI guys are lying...chode...hes running a stock LS6 cam with non stock springs

Hey genius, read my post. I said I dont think that's the OP's problem.And people do all sorts of stuff, does it make it safe? NO. Have you even built a boosted car before? Quit acting like you know what youre talking about simply because you've read it on the internet.

That is terrible info right there. You have MUCH more stress on the valvetrain on a boosted setup. Air is forced into the chamber rather than drawn in as in an NA setup. So everytime the valve tries to close the pressure in the system is trying to force it open. Im not saying his problem is springs but if you've hung around the Forced Induction section bad/weak springs have been ALOT of peoples problems, especially those with stock springs.

hmm...so tell me where my terrible information was if you were agreeing that it wasnt a spring issue....we all know those GM LS6 lobes are pretty tough to handle with a decent dual spring let alone a single stocker spring

Your horrible info is right here. You're basically implying that any boosted setup short of an all out race setup pushing tons of boost require a real valve spring. Plenty of people float LS6 springs, hell plenty of people float aftermarket double valve springs. You are not taking into account the added pressure due to boost. Not to mention that 13 psi in 1 setup is not the same as 13 psi in another setup, but I wont even go there.
oh and dont listen to these crazy's who are telling you than you have insuffiencent spring...people running 13lbs of boost on stock ls6 longblocks 02z cam and ls6 springs...the springs you have, have way more pressure open and closed

ok so in his particular setup me saying not to listen to others about springs because HE is running more than enough spring for his mild turbo and weak ass lobes on his stock GM cam...this is bad advise? hmm...I'd look elsewhere man for your problem

I just want to let everyone know that i appreciate the posts and advice.....

I am willing to try everything to get this figured out....

I got 2 more of the dyno sheets to post up.... one is in MPH, so maybee that will help...

Here are the other dyno sheets from the same day.... thought they might help.

http://i721.photobucket.com/albums/ww216/one_bad_ls1/100_0504-1.jpg?t=1256692196




Notice on the graph above the car only pulled to 5500 then dropped off... on the original graph i posted it made it to 5600 or a little more befor the power fell off.... also the power drop off isn't quite the same... WTF LOL



the graph below shows how the power drops off with the speed, ya it definetly doesn't help the performance of the car... Its makes 530 peak HP but with the way it drops off i bet an f-body with a solid 450hp would beat me at the track.... so dissapointing, this is driving me nuts!
http://i721.photobucket.com/albums/ww216/one_bad_ls1/100_0503.jpg?t=1256692278

What are you using to control boost? Ive seen a graph similar to that with an electronic boost controller setup wrong.
What gap on the TR6 plugs? ie is spark blowing out
What is the exhaust setup, are you running cats?
Did you try shimming the BOV and did you verify that it isnt opening under boost?
Did you do a compression test?

What are you using to control boost? Ive seen a graph similar to that with an electronic boost controller setup wrong.
What gap on the TR6 plugs? ie is spark blowing out
What is the exhaust setup, are you running cats?
Did you try shimming the BOV and did you verify that it isnt opening under boost?
Did you do a compression test?


I am using a cheap ebay boost controller.

gap was 18-20 on tr8's then tried autolite 103 (tr-6 heat equivelant) at 32 and no change so i dont think spark is blowing out...

no cats its a front mount Master Power T70 (homemade merge pipe with truck manifolds and 3" downpipe dumped by starter)

I did shim the BOV quite a bit (almost to much i think because the bov barely works now) and i gained about 20hp doing that (thats how i went 507 to 528hp)

I have not done a compression test on the motor yet... and have not checked the charge side for leaks because i have boost the entire run... it fluctuates a few kpa but not bad ( i have logs posted on the first post in the thread)




Another question...... could i have a head that is lifting causing this? I hear about people having problems lifting heads.... I never trying to turn down the boost and see what it did... but at over $100 for 3 runs its expensive and cant afford to keep doing runs on the dyno....

Does it feel like it noses over on the street like the graph shows?
From what I recall, youre not running much timing so I doubt you lifted a head. Was there any knock on the run?
I would try dropping the boost and see what happens. And honestly, if you have the means/tools....pull a valve spring and test it and see what happens.

Does it feel like it noses over on the street like the graph shows?
From what I recall, youre not running much timing so I doubt you lifted a head. Was there any knock on the run?
I would try dropping the boost and see what happens. And honestly, if you have the means/tools....pull a valve spring and test it and see what happens.

I can deffinetly feel and watch the rpms start to climb really slowly from 5500ish.....

No there is no knock coming up.... I did the first run at 17* and the next ones at 22*..... I am currently running 17* on the street (remeber i am low compression at around 8.5-8.7:1)

I will try to lower the boost and see what happens.... I will also log it with hptuners and use the timer at the bottom of the log to time the run... maybee it will be faster with less boost if the darn thing wont fall on its face... lol

I have a valvespring removal tool... but not sure how to test the spring tension.?.?

I am running the stock tranny also... It is slipping a little and is flashing way above the 3600 rpm stall...... lol, a new tranny is on the list of things to save for this winter....

valve spring tester....
http://www.summitracing.com/parts/PRO-66834/
Start with the easiest stuff first. Lower the boost to 8 psi or so and see what happens. I would check a valve spring or 2 next and then see about a compression test.
From that graph you only have a few explanations.....either spark was cutting out hard, fuel was cutting out hard, there is a clog in the induction/exhaust system, you have springs in BAD shape, there is a hole in some pistons lol.

valve spring tester....
http://www.summitracing.com/parts/PRO-66834/
Start with the easiest stuff first. Lower the boost to 8 psi or so and see what happens. I would check a valve spring or 2 next and then see about a compression test.
From that graph you only have a few explanations.....either spark was cutting out hard, fuel was cutting out hard, there is a clog in the induction/exhaust system, you have springs in BAD shape, there is a hole in some pistons lol.


Ouch! $65, lol.... the springs only have about 5000-7000 miles on them.... im pretty sure they are ok.... but if it eventually comes down to it i will break down and buy it, lol.


ok that makes it simple.... spark, springs, intake/exhaust, fuel, holes in pistons....

Damn i hope i didn't kill a piston already!!!! I would know though, it would smoke like a mofo and have horrible blowby and doesn't do either...

What would a dyno sheet look like with a lifting head? How do i know if i lift a head? Will it always blow out coolant or not?

as for compression... you would think it wouldn't have made it to 500hp if it had bad compression right???????

When a head lifts either you'll get coolant in the chamber, or more likely youll blow combustion into the coolant system. You can pressure test the coolant system with a tool at Autozone/Discount Auto Parts thats free.There are also testers that will detect exhaust in the coolant system. Have you checked your coolant level lately in the radiator?

When a head lifts either you'll get coolant in the chamber, or more likely youll blow combustion into the coolant system. You can pressure test the coolant system with a tool at Autozone/Discount Auto Parts thats free.There are also testers that will detect exhaust in the coolant system. Have you checked your coolant level lately in the radiator?

I i seem to have to add coolant every once and a while when the light comes on... I also have no overflow tank the tube just goes to the ground

I check the oil everyday i drive it and the oil looks good not milky or anything, I think it just pushes out when it occasionally gets to like 230ish temp when i do a long run on the highway....

Well havent had a chance to do anything.. we have had over 15" of snow the last few days and i dont have a garage! lol

keep us updated. If you need anything you still have my number.

oh man! cant wait til you figure this thing out.

wish mike wasnt such a nazi.....lol

oh man! cant wait til you figure this thing out.

wish mike wasnt such a nazi.....lol

ya lol... I am working on getting a th400 on here via payments to a guy.

th400 RMVB w/Trans Brake... then i have to buy all the other pieces for the swap like crossmember, stall, tranny lines, ect...

I will have 2000-2500 in the tranny swap, man ive spent so much money on this thing in the last year i have owned it, especially after all the different setups, lmao!

After the tranny i should be good for a while though. I have the 9", all the suspension mods, and now the tranny.... so i should be good for a while, lol.

Hell if the 5.3's last for around a year (5,000 to 8,000 miles), i can handle $400 a year lmao!

Just a thought but have you check for an exhaust leak before the turbo...when the RPMs get high maybe your exhaust starts leaking because the turbo gets harder to spin faster and faster...

Just a thought but have you check for an exhaust leak before the turbo...when the RPMs get high maybe your exhaust starts leaking because the turbo gets harder to spin faster and faster...

I havent checked for pre-turbo leaks... but according to hpturners the boost stays all the way through the runs.... I really dont think its a boost leak problem because i have boost through the entire run...

I will check though it cant hurt....

************************************************** *****

Im not gonna drive the car anymore until i get the th400..

My stock tranny is for sale..... $300 + shipping
If you read the whole thread you know that it may be slipping... not 100% sure but i might be so i would check it befor installing it (normall driving it has absolutely no issue... but when i go wot i lose power at 5500 and i think it might be the tranny)

My VIG 3600 triple disk is also for sale..... $450 + shipping (~8000 miles on it)

I was figuring on what gear to get for my setup with the th400... and an idea popped into my head...I used the calculator to figure what my MPH should be at each rpm and compared it to my log on the dyno and this is what i came up with:

RPM - DYNO SPEED - CALC SPEED : Difference - Efficiency

3100rpm - 071mph - 071mph : 00mph - 100%
3500rpm - 071mph - 078mph : 07mph - 091%
4000rpm - 073mph - 090mph : 17mph - 081%
4500rpm - 076mph - 101mph : 25mph - 075%
4700rpm - 078mph - 105mph : 27mph - 074%
5000rpm - 080mph - 112mph : 32mph - 071%
5400rpm - 086mph - 121mph : 35mph - 071%
5600rpm - 092mph - 126mph : 33mph - 073%
5700rpm - 100mph - 128mph : 28mph - 078%
5800rpm - 110mph - 130mph : 20mph - 085%
5900rpm - 114mph - 132mph : 18mph - 086%
6000rpm - 119mph - 135mph : 16mph - 088%
6100rpm - 124mph - 137mph : 13mph - 090%
6200rpm - 128mph - 139mph : 11mph - 092%
6300rpm - 131mph - 141mph : 10mph - 093%
6400rpm - 134mph - 144mph : 10mph - 093%


obviously the stall is not locked up so the mph is not gonna match exactly what the calculator said.... but it is a 3600 stall and seems to flash all the way to 5500rpm on the sheet i made above, and finally got below the 12% slip at 6000rpm... I have heard you never want more than 12% loss after your flash rpm...

Hope you can get it figured out man.

Since when does a Z06 cam require longer than stock pushrods? 7.4 should do it but with the head swap then it just becomes a guessing game unless you measure.

Since it came factory. LS6s had 7.425s.

But hes running stock heads so unless they are milled hes right with the 7.425s.

People here are very knowledgeable but they act like its voodoo magic when you start talking about 5.3s or 6.0 truck motors.

I don't think the turbo is too small. A guy I race with made 550 with a 5.3 and STS t60 turbo. But it did pop at 5500 rpm.

Here is a link to some more 5.3's with ls6 cams, it seems this may be normall for the 5.3 and ls6 cam?!? So maybee there isn't a problem, I am going with the th400 anyway.

http://www.performancetrucks.net/forums/showthread.php?t=450753&highlight=5.3+ls6+cam

Ouch! $65, lol.... the springs only have about 5000-7000 miles on them.... im pretty sure they are ok.... but if it eventually comes down to it i will break down and buy it, lol.


First, if you floated the valve several times I would install new springs. This is the fast track to removing stiffness from the springs. Second, you really need to check a few basics. First, remove two springs and take them to a machine shop if you don't want to buy the tool and let them verify they are still OK. Second, check your pushrod length. Third, check the valve spring installed height. Tony has a lot of experience, and if he is correct and you are losing control of the valve train, every time you rev it up you are risking hitting a valve with a piston.

First, if you floated the valve several times I would install new springs. This is the fast track to removing stiffness from the springs. Second, you really need to check a few basics. First, remove two springs and take them to a machine shop if you don't want to buy the tool and let them verify they are still OK. Second, check your pushrod length. Third, check the valve spring installed height. Tony has a lot of experience, and if he is correct and you are losing control of the valve train, every time you rev it up you are risking hitting a valve with a piston.


Here is the rundown on my PRC Duals with titanium retainers good to .660 lift valve springs.

used them in a cam only (227/231 .614 .617 112+2) setup for about 3500 miles, got an sts kit and ran the same cam with 8psi for 2000 miles killed #7 ringland, now they are in this motor for 500-700 miles and have this problem....

So is it possible for the springs to worn out in 8000 miles? I just find it really hard to have vlave float with PRC duals and an 02 ls6 cam... Although Crazier things have happened....

Not saying its impossible, just saying it SHOULDN'T be happening.... I am going to see if the tranny will help the issue out first....

I do believe i need to get a pushrod length checker and make sure 7.425 are the right lenth.

Check Valvespring Installed Height????? How do i do this?????

The fact the springs are used add even more fuel to the fire regarding potential valve float issues...especially if say a couple are really bad for some reason.

But honestly, the drop in power is so severe, it would be the worst case of valvefloat I think I have ever seen so its really just another option or should I say just another potential fix/solution of your problem (but high on the list IMO).

-Tony

Does it just fall on it's face but still sound good or does it break up, surge, buck?

If it sounds good but isn't making power to the wheels then it's likely the transmission or converter eating your power.

The fact the springs are used add even more fuel to the fire regarding potential valve float issues...especially if say a couple are really bad for some reason.

But honestly, the drop in power is so severe, it would be the worst case of valvefloat I think I have ever seen so its really just another option or should I say just another potential fix/solution of your problem (but high on the list IMO).

-Tony

Tony what springs would you suggest for my setup? I may just get new spings when get the cash saved after the tranny...

Does it just fall on it's face but still sound good or does it break up, surge, buck?

If it sounds good but isn't making power to the wheels then it's likely the transmission or converter eating your power.

it doesn fall on its face so to say its sounds good no break up, surge of bucking.... it just pulls like a mofo till 5500-5600 then stops pulling as hard like i lose 100hp....

to be honest i didn't realize it was that bad till i dynoed it.... I did notice the rpms climbed alot slower afer 5600 but didn't realize it was that bad.

it doesn fall on its face so to say its sounds good no break up, surge of bucking.... it just pulls like a mofo till 5500-5600 then stops pulling as hard like i lose 100hp....

to be honest i didn't realize it was that bad till i dynoed it.... I did notice the rpms climbed alot slower afer 5600 but didn't realize it was that bad.

Does it fall off at the same RPM regardless of the gear or does it only happen at the top of 3rd?

I only notice it at the top or 3rd it goes through 1st and 2nd pretty fast!

I only notice it at the top or 3rd it goes through 1st and 2nd pretty fast!

I would think that if it was doing it in 2nd, you should feel it drop that much. Smell the transfluid. Sounds like trans/converter to me.

I would think that if it was doing it in 2nd, you should feel it drop that much. Smell the transfluid. Sounds like trans/converter to me.

the trans fluid looks/smells fine.... It shifts fine under normally driving... but i think it may be slipping at WOT, that why i stopped driving it....

I am selling the converter and trans... and am in the process of buying the th400... I planned on getting a th400 anyway.

I though about keeping the trans for a mustang build because i think its fine it just cant hold the power at wot... but I need the money so im selling it.

Looks like there is possibly a restriction somewhere? Valve float usually looks like a rev limiter, not saying that you don't need some better valvetrain parts though. I would look through the turbo system for a restriction somewhere, is this an STS kit? Maybe even check the air filter etc. Just my 2 cents.

the trans fluid looks/smells fine.... It shifts fine under normally driving... but i think it may be slipping at WOT, that why i stopped driving it....

I am selling the converter and trans... and am in the process of buying the th400... I planned on getting a th400 anyway.

I though about keeping the trans for a mustang build because i think its fine it just cant hold the power at wot... but I need the money so im selling it.

If you haven't chosen a converter yet, I highly recommend FTI (they are a sponsor now). I been hooking good for a couple years on his converter. He's switched it around for me a couple times for different setups that I have run (N/A, Nitrous, and now FI). Super quick turn around on restalls also.

Try not to change anything else so that you can be sure that you have isolated the problem.

Looks like there is possibly a restriction somewhere? Valve float usually looks like a rev limiter, not saying that you don't need some better valvetrain parts though. I would look through the turbo system for a restriction somewhere, is this an STS kit? Maybe even check the air filter etc. Just my 2 cents.

Its my Homemade Front Mount Kit:

Exhaust side: truck Manifolds -> 2.5" merge pipe -> turbo -> 3" downpipe dumped by starter

Charge Side: K&N 7" long 5" wide cone filter -> turbo-> 3" pipe-> 3" intercooler-> 3" pipe-> Stock Ported TB

I will try taking the filter off and see how it does when i get the th400 in... you never know i guess.

************************************************** ****

Hey guys I really appreciate the help and suggestions!!!! I am really willing to try anything and will try everything. Its more than likely something really simple!!! LMAO...

Things to try:
Th400
Check valvetrain / try new springs
Check for restrictions in charge/exhaust side

th400 will be in tomorrow...

I was looking at parish8 dyno and his pulls to 6300-6400, I think he used an 01 ls6 cam...

http://www.neufamily.org/images/fairmontgallery/zo6dynofinal.GIF

It isn't my cam thats causing the issue is it? I have an 02 ls6 cam... I think it would actually be better than the 01, but maybee there is something i dont understand...

Does this thread look familiar?

http://www.ls1tech.com/forums/forced-induction/1086821-boost-guys-opinion.html

http://www.ls1tech.com/forums/generation-iii-internal-engine/1086770-rev-issue.html

I have not changed my cam yet. Done a bunch more work to ensure no back pressure in fact since I have done more work I now can get 20 psi in 3rd and 4th gear but as soon as I hit 5000 rpm the car is done.

Kane

its crazy i hope we figure it out... i hope mine is the transmission.

TH400 is installed... have to get a Driveshaft now...

was just reading a thread on some other site where they were talking about oil pressure and preload:

even with the smallest amount of preload, with high oil pressure, and especially higher RPM where the lifter is getting filled quicker, it has a tendency to overcome some of the spring pressure and leave the valves open

IDK seems interesting... im am running a 10/30 conventional oil right now and oil pressure is like 60+ at 3000 rpm up... im gonna switch to mobile 1 synthetic oil and a lighter weight and see if it will help... also waiting on a pushrod length checker.

If my preload is not right then it can be causing some valve float also...

Alot of experienced people say its valve float. So im gonna try some things and if it doesn't help ill buy some springs.

^^ holy shit you figured out your signature!

You like that!!!

ya i left it over night and it was there the next day, i never had a porblem with the sig befor lol.... i wasnt do anything wrong the damn thing just wouldn't take it right away lol...

i was getting so pissed! lmao