Drag Racing Results - Typical ranges on a 10 second time-slip?

Just added a new combo this weekend and dynoing it today with a tune. If the weather is good I want to go tomorrow night. I have no bar so I will just make 1/2 track passes until the end so... what is the typical range for a high 10 second pass @ 3800 lbs? I may not have enough to do it but figure I will need:

1.49 or better 60'
6.90 1/8th
100 MPH 1/8th

Sound about right?

I would love to pull a 10.9 with it first time out.

i would say around 98mph with a low 1.4 60ft should about squeeze you in

Just added a new combo this weekend and dynoing it today with a tune. If the weather is good I want to go tomorrow night. I have no bar so I will just make 1/2 track passes until the end so... what is the typical range for a high 10 second pass @ 3800 lbs? I may not have enough to do it but figure I will need:

1.49 or better 60'
6.90 1/8th
100 MPH 1/8th

Sound about right?

I would love to pull a 10.9 with it first time out.


I would say your right on the money. I have trapped 97 in the 1/8 with 1.48 to 1.46 sixties at 3550 race weight and my car runs consistent 11.1's with a best of 11.04.

Well I only got 393 RWHP on the dyno tonight so fat chance of that. Time to pull a new combo out of my ass. LOL

Well I only got 393 RWHP on the dyno tonight so fat chance of that. Time to pull a new combo out of my ass. LOL

Dyno's don't mean a damn thing. My times are in my sig, and it is definitely going to net a 10 second time slip next time I vist a 1/4 mile track. It ran 11.teens @ 122 when it was 3 tenths slower in the 1/8. My little motor just made 396 to the wheels, no dyno queen here!! lol

Well the bad thing here is it dropped like a rock at 5700 RPM

Well the bad thing here is it dropped like a rock at 5700 RPM

Did your AFR lean out after 5700 - if so maybe look at fuel filter, pump or injectors.

What valve springs did you go with - possible valve float?

Did you measure for proper pushrod size?

Is your new throttle body opening to 100% - can check that with a scan tool.

You still have the 224/228 cam?

I have a 224/227 cam and swapped to a tv2 cam thats 232/234 and even though my peak hp was only 30hp higher, my hp at 6,300 was 60 more hp!!!!!

Big difference on the big end of the track. Its seems these motors love cams with 230 or higher duration. My converter is 3600 and the combo is sweet.

Did your AFR lean out after 5700 - if so maybe look at fuel filter, pump or injectors. -Brand new 42's installed 10 minutes prior. No filter/pump fueling problem

What valve springs did you go with - possible valve float? Patriot Gold (.650 lift) were on the new heads

Did you measure for proper pushrod size? I'm running adjustable 1.85 Comps. We measured the wipe pattern by marking the top of the valves

Is your new throttle body opening to 100% - can check that with a scan tool I watched the tuner adjusting everything tonight and when he would go WOT it showed 100 on the HP Tuners Valve float. Don't know but the springs are good to .650

Dyno's don't mean a damn thing. My times are in my sig, and it is definitely going to net a 10 second time slip next time I vist a 1/4 mile track. It ran 11.teens @ 122 when it was 3 tenths slower in the 1/8. My little motor just made 396 to the wheels, no dyno queen here!! lol

justin, i have a huntch that your car dont wiegh 3800 and the dyno you were on may read a little low at times. lol

Well the bad thing here is it dropped like a rock at 5700 RPM

Valve float. Don't know but the springs are good to .650

what lift they go to isnt the important part. what was the closed pressure @ installed hieght? open pressure? are the springs new or used? are you running stock or aftermarket rocker arms?

but even if it didnt fall off and peaked at say 6300ish like it should with that size cam, what numbers were you exspecting with budget heads and a 224 cam thru a stalled auto?

Just added a new combo this weekend and dynoing it today with a tune. If the weather is good I want to go tomorrow night. I have no bar so I will just make 1/2 track passes until the end so... what is the typical range for a high 10 second pass @ 3800 lbs? I may not have enough to do it but figure I will need:

1.49 or better 60'
6.90 1/8th
100 MPH 1/8th

Sound about right?

I would love to pull a 10.9 with it first time out.

I've got 10's with 1.54 6.98 @ 97. but that netted me a 10.989 or so, so with my 1/8th mile it barely squeeks in.

justin, i have a huntch that your car dont wiegh 3800 and the dyno you were on may read a little low at times. lol





what lift they go to isnt the important part. what was the closed pressure @ installed hieght? open pressure? are the springs new or used? are you running stock or aftermarket rocker arms?

but even if it didnt fall off and peaked at say 6300ish like it should with that size cam, what numbers were you exspecting with budget heads and a 224 cam thru a stalled auto?

The heads/springs are brand new out of the box:

Spring Pressure Closed: 135 lbs. @ 1.800"
Spring Pressure Open: 375 lbs. @ 1.090"


I'm running Comp Magnum 1.85 adjustables and I guess I was expecting around 420. The compression is bumped to 11:1 and I have the intake. I have seen some with just cams do my number.

ok, your goal is not out of reach by any means. just wanted to make sure you had a realistic number in your head. even tho you cant put faith in numbers like 358chevy said earlier. i think the problem lies in the rockers. no need for adj rockers on your combo that i can see, unless your leaving somethin out. aftermarket rockers tend to be alot heavier on the valve and lead to valve float. alot more spring is usually needed to control them. find your stock rockers and rock out..... i bet your problem goes away

No. I had the 1.85 adjustables for more lift on the stock cam. This cam is designed for use with the 1.85's... why I went with it. It puts the lift at .580 with the rockers. But if it cures a problem I could run the stock rockers and have less lift. Other option is pull the cam, go back to stock rockers and use maybe a larger lift/duration cam that will still work great with the springs.

No. I had the 1.85 adjustables for more lift on the stock cam. This cam is designed for use with the 1.85's... why I went with it. It puts the lift at .580 with the rockers. But if it cures a problem I could run the stock rockers and have less lift. Other option is pull the cam, go back to stock rockers and use maybe a larger lift/duration cam that will still work great with the springs.


I would try stock rockers before you do anything else.

I would try stock rockers before you do anything else.

Thats what i told him. I will post graph in alittle.

If you got 393rwhp with the converter locked, you have no chance of running 10s. If that's unlocked on a load bearing dyno, 10s is certainly possible at Cecil - just pick the right day ;)

Still, that combo is a bit mild for 10s at full weight.

Thats what i told him. I will post graph in alittle.
Yup and I think we will try that. I may have track numbers before you post the graph... I'm going to the track tonight.

11.46@118 MPH but the weather was moist and we got rained out.


Fran... Graph?

11.46@118 MPH but the weather was moist and we got rained out.


60' time?

1.55 60' and 7.28 1/8th

That's a pretty good 60' time. My first time out with the current combination netted me a 11.484 @ 121.26 on a weak 1.729 sixty foot. 1/8 was 7.417 @ 95.54 MPH. My first 10 second pass was 1.536 60', 6.991 @ 98.66 in the 1/8, 10.955 @ 124.21 in the 1/4.

Put that pig on a diet...Do you have the aluminum driveshaft? front bumper support, front sway bar. abs delete, airbags. k-member.

Put the stock rockers back on, there is no way 1.85 rockers are going to be stable on any cam with an agressive ramp rate! You gained 40hp and picked up 4mph seems about right. There is way more in that setup though, dont get discouraged. What injectors are you running? Is that the patriot cam they sell for $250?? If so that cam is pretty lackluster from some results I have seen with a magazine build.

Put the stock rockers back on, there is no way 1.85 rockers are going to be stable on any cam with an agressive ramp rate! You gained 40hp and picked up 4mph seems about right. There is way more in that setup though, dont get discouraged. What injectors are you running? Is that the patriot cam they sell for $250?? If so that cam is pretty lackluster from some results I have seen with a magazine build.

It's the Comp Cams XR277HR designed for 1.85 rockers

Lobe center:112
Intake centerline:110
Duration at .050":224/228
Valve lift: .534/.537
RPM range: 2000-6800

This is with 1.7 rocker ratio

11.4 @ 118 sounds about right. If you want to go faster you'll need to get more aggressive with the camshaft and converter. I had a very similar combo (full weight too) a few years ago that netted me a 11.3 @119 at Cecil. That made 380rwhp unlocked on a Mustang. I've since added a little more compression, a larger cam, and a better converter and have picked up .4 and 4 MPH.

You may go quicker and faster with better track conditions and some tweaking, but not 10s, sorry.

And I see you changed your sig. Didn't you list Stage 3 heads yesterday?

Yea after the track visit. My Patriots are 2's. I think the 2.08 valved heads are 3's.

I guess the only other way would be to take out a ton-o-weight

http://i121.photobucket.com/albums/o225/Frans402/Jessie.jpg

If you ran 11.4 with that power curve you will have no problem hitting 10's when you gain valvetrain stability! It should pull up to 6500 no problem!

I guess if I have that extra 30-40 HP available from 5700-6500 on the shifts and more importantly in D on the back end it should pick up a couple MPH and a tenth or two minimum.

Well I did a search and found a post similar. At the bottom is a link to another post where they saw a similar problem:

http://www.ls1tech.com/forums/dynamometer-results-comparisons/691122-new-dyno-s-my-h-c-lt1-does-look-like-valve-float.html

That dyno is with the converter locked right? No way will it see 10s at your weight, even if you figure out your issues. Now if it made that unlocked... :D

Unlocked

Unlocked

Not on that graph that was posted. Either that or you have a stock converter.

Not on that graph that was posted. Either that or you have a stock converter.
Maybe then. What gives you that thought? I asked them if we could change the lock-up setpoint and I don't have a multi so we couldn't. Since they didn't want commanded lock-up I have to assume that is unlocked.

It was locked. We can manually lock it on the dyno jesse but you dont have WOT lock up on the street.

Congrats on the pb, it will move out once you get it figured out...


Sorry to sound like such a newb with this question, but is it hard on the trans to have locked at wot?.. Can playing with the lock up effect the mph?

Nice topic

Well we switched to the stock 1.7's today and the car started hitting the rev-limiter like butter.

It's making power past 6200 now. I think it does have an 11.20 over 120 MPH now in it.

Very weird it never hit the rev-limiter on the 11.46 pass. Today it was hitting it good so something has changed.

Dyno'd again yesterday. I have the printout but Fran has the file. Basically 398.51 RWHP/ 378.63 Torque but the curves are very flat unlike the other and smoothe. Peak HP number was at 6300 RPM with no drop-off like before. No 9" or DR's and Fran said the numbers would have been higher. I maybe should have held off on the 9" but I like piece of mind! I think it should do a little better now.

Managed to scan it in :pics:

Nice! 11.3-11.2s is def possible

So the big question is will it pick up .2/2 MPH. If it goes 11.20@120 I think mission is accomplished with this combo. Will the better curves and useable RPM pick it up that much?

Def think its possible, if it doesnt then pull a tad more weight out. On your 11.4 pass what were you shifting at? What are you shifting at now? Also do you what the da was on your 11.4 pass

I don't know the DA but it rained us out. Very moist and not exactly cool. It was still shifting at 6200 RPM but as the first graph showed it wasn't making power there. 40's and dry Saturday so it should have good air.

Thanks to Fran and his guys for helping identify the problem and tuning the car!

I think it will still run hard for what it is. For best results you need to run a properly specced cam with 1.7 stock rockers. I am sure there is another 20hp available in your setup without going to a huge cam.

The 1.85's were great on the stock cam with the upgraded springs and would have worked here with even heavier springs and gave a nice gain. Now that I entered a different area though it is better to just use the stockers and a bigger stick.

I don't know the DA but it rained us out. Very moist and not exactly cool. It was still shifting at 6200 RPM but as the first graph showed it wasn't making power there. 40's and dry Saturday so it should have good air.

Thanks to Fran and his guys for helping identify the problem and tuning the car!


Do you have time and date of your 11.4 pass? From the sounds of conditions I'm sure air wasn't great. Yeah Saturday should have great air, let us know what it runs. One of these days I need to make it up to cecil county. Here is a link for da calculator, its not 100% accurate but it will give you an idea: http://www.dragtimes.com/da-density-altitude-calculator.php?elevationcorrect=-279&et=11.83&mph=114.3&correctetmph=Correct+ET+and+MPH

How do you use it to figure things out? My pass was made 6:40 PM 10/28/09. How can I use that to figure what it would have run in good air. Also... where can I find conditions on that day?

I see!

Temp wasn't bad 50's. Humidity was over 93%


Correct your ET and MPH using the DA (Beta Testing)


Density Altitude:
feet above sea level

1/4 mile ET:
seconds

1/4 mile trap speed:
MPH




Stock and Mildly Modified Naturally Aspirated Engines
11.407 @ 118.347 MPH

Extensively Modified Naturally Aspirated Engines
11.476 @ 117.839 MPH

Extensively Modified Supercharged and Turbocharged Engines
11.466 @ 117.789 MPH

How do you use it to figure things out? My pass was made 6:40 PM 10/28/09. How can I use that to figure what it would have run in good air. Also... where can I find conditions on that day?

http://www.dragtimes.com/da-density-altitude-calculator.php Enjoy!