Question for the 4-digit hp crowd

tannerc91gt

This last 25% is foreign territory at this point
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Nov 29, 1999
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Here’s the most on-topic SBF related post you’ll probably ever see me make.

I’ve had a coupe in my shop for the last month or so putting a Holley EFI system on the turbo 306 combo. Made some small changes to the turbo kit, fuel system and just general wiring cleanup. It’s a really solid car, 8.50 cage, built-ish rear end, etc. Its just a bit outdated for 2019.
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Anyways, the owner is ready to get back into class racing and that means basically starting from scratch on this deal.

Engine,trans,converter, rear end have been sold.
Will need to make 1200-1300fwhp range with the new combo to be competitive.

He has an R block based short block (347”), hi ports, will get a custom cam and converter, a glide and a new rear end as well as a much larger turbo than the little guy pictured and an a2w system.
I’ve converted it to crank trigger, cam sync and COP as well.

Is anyone on this forum making that kind of power? I know we don’t have quite the same group we did in the prime Stangnet years.

I’m just curious if there are any “must do’s” to keep a SBF combo happy at that power range.
And if the Vic jr and elbow is the typical route people stick to or if a super vic or something else (the Holley hi rams never seemed to catch traction with the SBFs).
If this car were LS based, it would have a hi ram on it. I imagine we will need to spin it to 7500+

Bit of a rambling post, but hopefully some good info can be shared
 
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@84Ttop (must have wrong screen name there) is who comes to mind with this question. He was a 400"+ motor with a vortech, but pretty sure it went over 1400rwhp at its peak. I know that doesn't answer your question, but maybe someone to reach out to.

Joe

Edit: looks like the screen name took.
 
@84Ttop (must have wrong screen name there) is who comes to mind with this question. He was a 400"+ motor with a vortech, but pretty sure it went over 1400rwhp at its peak. I know that doesn't answer your question, but maybe someone to reach out to.

Joe

Edit: looks like the screen name took.


Last seen in Feb! :fuss:

Kick his ass when you see him.
:leaving:
 
From what i understand you can treat the engine as if it were an LS in regards to most of the power tuning with a modern cylinder head and piston design. The power range you guys are shooting for is about 400hp farther than anything i have tuned so I am interested to see how you get there.
Is this going to be E85 or 114?
 
My turbo cars (954 and 889 rwhp, to date) have a ton of back pressure, which can/will ultimately both restrict power gains and prematurely wear exhaust valves. Go with a T6 housing, and make sure the exhaust wheel is known for the power level. As long as you have heads/intake/cam that's in the ballpark, the turbo does 90% of the work. Regarding the questions about the upper end, just remember that you build the upper based on the volume of the motor. Boost does affect flow, but less than you'd think. A motor that makes good power n/a will also make good power on boost. IMO, only the cam needs adjustment. Other than that, make sure it's got a good cooling system, and that the heads and block are ultra smooth for the MLS gaskets. E85 vs. race gas doesn't matter too much, but you need more pump and injector for the E85. If you have it, then you can run either. That's about all I can think of.
 
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100% Methonal/E85 is the direction I would go as already stated. Tune is more forgiving with meth/eth, depending on your customers tuning experience. Mike Moran would be a good resource for fuel system and beyond.
 
Yes larger tuning window and runs way cooler! For drag only you can get away dry blocking with Methonal, you can never get away with that on gasoline.

For NA I use to run 15-16:1 compression dry block all iron in tractor pulling on Methonal. Head would be 200 degrees at end of the run.
 
The class is gas/e85 only, it’ll be run on E85.
We will run either an ultra legal cast 76 or a turbo specific to the class if one becomes available.
DXP235 is the class it’s being built to run.
Front runners in that class run 5 teens at 3200-3400lbs so about 1200-1300fwhp
 
Custom turbo should be here any day now. Will get the new front in welded on this coming weekend and then yank out this drivetrain.
Everything from balancer to diff cover is sold.
Looks like this car is going to be hanging around a while lol
 
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