Small Block & Big Block Chevy Specific - SBC Blow through help




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singe
10-07-2009, 05:58 PM
Im building a 383 stroker to go in my...cough...Mustang. Anyhoo, I need a bit of advice. Im putting a rather larger turbo on the 383 (recommended by turbonetics) and I may have messed up. I bought a turbo cam rather then just playing it safe and calling them for a custom grind. Its not to late to do so, but what would you guys think about this cam i already have. It seems a bit large if youd ask me. Ive spent alot of money on this build and dont wanna screw it up by running the wrong cam. Here are the specs from the card:

Part # 12-405-5 (Comp Cams)
Specs INT EXH
Adv Dur 290 300
Dur @ .050 256 265
Lift .540 .563
LSA 114

Heres a few pics of the carb setup just for the fun of it. Thanks for your help guys.
http://img17.imageshack.us/img17/7691/pa020007.jpg
http://img363.imageshack.us/img363/3671/p8250002.jpg


NemeSS
10-07-2009, 06:13 PM
make more sense to go with cam tailored to your application,
is that a dual plane intake?

singe
10-07-2009, 06:21 PM
It is dual plane


NemeSS
10-07-2009, 06:28 PM
dual planes are usually not recommeded for blow thru, im not saying they dont work. iirc, it needs staggered jetting and is more tempermental than a single when calibrating. i used a vic jr on last blow thru engine i built,
i would not run a single plane in any blow thru build, but thats just me

singe
10-07-2009, 06:34 PM
Its hard to find decent information on this. Thanks for your help! What rocker arms did you use? 1.5 or 1.6? Its the little details that seem to be my issue. I was very unhappy with the quality of my intake anyway. Now I have a reason to get a new one :D

NemeSS
10-07-2009, 06:41 PM
Its hard to find decent information on this. Thanks for your help! What rocker arms did you use? 1.5 or 1.6? Its the little details that seem to be my issue. I was very unhappy with the quality of my intake anyway. Now I have a reason to get a new one :D

just summit 1.6 stamped steel replacements. the engine is a cast iron heads rebuilt 355ci. with a summit flat tappet cam. car makes around 450hp with pump gas and fmic
go to
turbomustangs.com
they have some of the best info about blow thru on the net. and there is even a sbc/gm section available

singe
10-07-2009, 07:22 PM
Thanks. That website has alot of good stuff on it. Ive almost built another engine with the ammount of screw ups and wrong parts ive gotten.

ZONES89RS
10-08-2009, 01:27 AM
For all out strip that is a good cam, but NOt for that dinky intake.

singe
10-08-2009, 04:06 AM
Yeah, the intakes going away very soon. Is this cam going to be choppy? I dont want to deal with that crap like my truck. Very tempermental.

ZONES89RS
10-08-2009, 12:14 PM
Well, with a turbo you dont need that big of a cam. That mother effer id big and nasty. It is right on the border of full drag and at the end of pro street.

So very choppy idle characteristics.

NemeSS
10-08-2009, 12:58 PM
Yeah, the intakes going away very soon. Is this cam going to be choppy? I dont want to deal with that crap like my truck. Very tempermental.

a stock type cam works well with a turbo. if youre looking for street car manners.

singe
10-09-2009, 03:31 AM
yeah, I dont want much of a "cammed" sound anyway. Any other tricks anyone has ran into I should no about?

ZONES89RS
10-09-2009, 11:26 AM
Get a milder cam, the boost will take care of the rest. Something in the 220s @.050. but over 600 lift as possible.

NemeSS
10-09-2009, 12:57 PM
Get a milder cam, the boost will take care of the rest. Something in the 220s @.050. but over 600 lift as possible.

sounds like hydraulic roller specs, i think hes using flat tappet cam

singe
10-09-2009, 01:50 PM
Yeah, Im using flat tappet. I just got a match sheet from turbonetics. I think the one they recommended is a bit overkill. Its their midframe 1500 hp turbo. Im just looking for 600 or so horse for now.

camarols1
10-09-2009, 02:24 PM
Ditch the pro-stock cam for something in the 220 range @ .050 on about a 113lsa.
Run a single plane intake to match the heads.
Blow through carb tuning is touchy, especially with a FMIC, so save up to have the carb modded/tuned by a shop like CSU etc.
Huge cams make the tuning process that much more difficult.
Make sure to get a custom converter from a company that knows turbo builds to ensure you are happy with the street manners.
Again, turbomustangs.com has some great info on this topic

NemeSS
10-09-2009, 02:38 PM
Ditch the pro-stock cam for something in the 220 range @ .050 on about a 113lsa.
Run a single plane intake to match the heads.
Blow through carb tuning is touchy, especially with a FMIC, so save up to have the carb modded/tuned by a shop like CSU etc.
Huge cams make the tuning process that much more difficult.
Make sure to get a custom converter from a company that knows turbo builds to ensure you are happy with the street manners.
Again, turbomustangs.com has some great info on this topic

so how do you like your ls engine over your prev. b/t setup??

camarols1
10-09-2009, 11:52 PM
Now is a bad time to ask, since I'm still working the kinks out of the tune...lol
It is up and running, but I need to get the tune close enough for a test drive before taking it to Speed Inc for a dyno tune.
I can't wait for it to be under full power. It is much quieter with the turbo too.
Single digit et's by spring for sure...

Jim

willdevilman
10-10-2009, 10:06 AM
I found all the help needed on turboforums.com that's all those guy do is blo thru combos. And like mentioned above CSU is a godsend! I had all kinds of trouble with my chevelle when I went blo thru, till I went on the turbo forums, lots of very usefull knowledge and help

An yes that cam is waay to big. My F1R procharged 588 BBC is running a hyd roller with like 236/246 at 50

ZONES89RS
10-10-2009, 06:00 PM
Yep, TTF is like the LS1 tech of turbo info.

singe
10-12-2009, 03:11 AM
Are you guys running aftermarket blocks or original?

willdevilman
10-18-2009, 12:43 PM
My 588 is a Dart big M block

singe
10-19-2009, 05:16 AM
Thanks for the info man. Im not going to chance busting the block. Dart were the ones I was looking at.

ZONES89RS
10-19-2009, 12:38 PM
LOL, you would be amazed at what a stock block will handle.

Especially on boost, since boost comes on gradual it makes them last allot longer.

willdevilman
10-20-2009, 06:58 PM
Zone is right a stock block will handle alot. The only reason I have an aftermarket block is cuz the guy I bought the short block from built it that way. I had a 70 something 2 bolt stock block 489 that held up to 15 lbs an never had a problem.

I had main studs installed and that's it

k5383
10-20-2009, 07:47 PM
I don't have anything to add....

But I must give you props on those valve covers!!!

NemeSS
10-22-2009, 01:53 PM
Zone is right a stock block will handle alot. The only reason I have an aftermarket block is cuz the guy I bought the short block from built it that way. I had a 70 something 2 bolt stock block 489 that held up to 15 lbs an never had a problem.

I had main studs installed and that's it

im pretty sure the nwer late model roller blocks can hold some power with supporting mods.