http://forums.corvetteforum.com/showthread.php?t=850274

Stock TPI alluminum.

 

Nobody believes that the stock tpi unit has it's place. Everyone says that 'it runs out of breath' and can't make any power. With the right gear and combo, it runs just fine.

 

Reading that sort of makes me think a little. I wanted to build a 383, but I don't really want to do with an aftermarket intake. I know for the best results I should go with a shorter tube runner intake, or atleast a streetram, but I worry about smog and carb numbers here in Cali. Seeing a 383 with a stock TPI pull low 12's makes me think of doing it, and seeing my results. I know it won't flow as good as it can, but port out that stock intake, and get some nice runners, and see if I can run some 12s.

 

The stock TPI intake system is good for around 200cfm maybe slightly less. That works out to around 400 HP in a perfect world. I believe he had AFR 190 heads without going back to check. They flow around 250 cfm without looking it up in stock form.

The key would be to make the TPI intake the main restriction. Have a very good flowing intake from the airfilter to the throttle body. Then have an excellent flowing exhaust system. With the very good AFR 190 heads who knows what would happen with a 190-200 cfm flow rate from the air filter to the exhast tip.

Now with a better flowing TPI it would be interesting. In fact I'am trying to do that right now. Only I'am using the new Trick Flow 23 degree heads. Extrude honed Edelbrock TPI manifold. Fully ported stock plenum. Early SLP runners fully siamesed on one side and siamesed at the bottom and top on the other side.

In a couple of weeks should have some dyno reports. Allen

 

I'm not gonna dog on stock TPI, but look back at that thread closely. The guy who did the 12.02 run gained a whole 6 to 7mph from just an intake swap from the stock TPI!!!! That's pretty impressive towards the aftermarket intakes...most notably the Superram since it actually gained in the upper by shaving .6 seconds off the et, and even shaved .04 off the 60ft time!!! I guess stock tpi isn't that bad.....but I'd still go for something else since it shows that it does fall on its face up high......stock.

 

Imagine if the base and plenum were ported a bit.

I have always imagined that stock TPI alluminumcould break into the 12s, however everything thing else needs to be in perfect alignment to produce those results.

light car
slicks skinnies
right gear
vigilante converter
383
heds/cam


Which is what we are looking at. When that much money and consideration are invested, who the hell care about dropping another $1000 on an intake.

But interesting none the less.