KMO43

I thought it was built

SylverSS/SC

iTrader: (3)

Top end is stronger than the stock bottom end. When I change tuning programs, I'll spin it faster. Maybe 6500 or 7000. Gotta find stock size forged piston first

KMO43

Stock rods? Forged crank?

KMO43

What year?

KMO43

And please tell me you upgraded the 3 speed trans

SylverSS/SC

iTrader: (3)

There's no upgrade lol. The th400 is a drag tranny, I'd need to get a seperate computer to control a 4L80E or revert to a 700r with a manual kickdown cable

SylverSS/SC

iTrader: (3)

They never put forged internals in any 454's

KMO43

So it's a 3 speed with 3.73s?

SylverSS/SC

iTrader: (3)

Yup. The 91-93 had a 4L80E with 4.10's in the rear end. Gets about the same mileage as the 90's

KMO43

When's it gonna be done then?

SylverSS/SC

iTrader: (3)

Put back together or pushing 20 psi?

KMO43

Well boosted

buy this: around 8:1cr

http://www.summitracing.com/int/part...make/chevrolet

SylverSS/SC

iTrader: (3)

Won't be for a couple years

KMO43

So you are gonna run it no boost?

SylverSS/SC

iTrader: (3)

I'm not going to turn it up past 8-10 for a while

soundjunky

iTrader: (4)

this is where aftermarket balancing and align honing come into play;
They both play into being able to extend useable rev limit.

there is absolutely nothing wrong with the th400, most guys not wanting to go to a computer assisted automatic want a th400;
In years bygone I swapped one into my youngest brothers '77 Trans Am - as an upgrade from the original th350.

KMO43

I still think you'll need fueling or tuning past 10psi

SylverSS/SC

iTrader: (3)

I have a 255 LPH pump, slightly larger injectors and an adjustable regulator. Fueling is fine. I was looking at a gear vendor overdrive unit but those are $3,500.

I can get forged cranks and rods, finding stock bore pistons is the problem

KMO43

But good enough for 20psi??

KMO43

With only 4 injectors for it to be enough fuel I'm guessing the injectors will have to be at 100% duty cycle pretty much stuck open under WOT

KMO43

For around 600whp at 80% IDC it'll need 141lbs or 1500cc injectors at 43.5psi

KMO43

Your 80lbs are good for 535bhp at 43.5psi

SylverSS/SC

iTrader: (3)

only 2 injectors. both are about 90 lbs/hr at a certain fuel pressure. Not sure what pressure it is

KMO43

If you increase the fuel pressure from what they are rated at it will improve the injector flow until you have too much pressure and then you'll be out of the pump efficiency window but only with 2 90s I think you'll be fine. I'm guessing your fuel pressure will increase 1:1 with boost so you have ~43psi at idle and 53psi at 10psi of boost?

SylverSS/SC

iTrader: (3)

8-13 psi at idle is stock. The tbi is good for up to 450-500 hp