Let me know what you guys think. I need input.
I have a 476 inch big block ford.
motor will be right around 10:1
74cc trickflow powerport 429/460 heads
running on E85 and blow through dominator carb setup.
solid roller cam.
My horsepower goal is at least 1200+ or low 5 sec 1/8th mi.
Running 2 76mm chargers.
powerglide trans.
car is around 3200lb

not a street car but I may do a couple of 10 mi street race trips haha.

questions,
what exhaust AR should I be looking at? I was thinking around .9 with a T4 flange
I would like to keep this under 7000 rpm

what kind of boost will I need to run?

what kind of horsepower is this capable of making?

 

all 76mm turbos are not created equal so my first question is whos 76 will you run

 

if it was me on a budget I would run the ebay gt 45 with 1.05 A/R and let it eat ....your big block with 2 of those should exceed your goals .... a single gt45 on a 5.3 ls1 in a mustang went 5.90 and drove to the track

 

I was planning to use the on3 76mm with .96 ar.

 

im not an expert but I think the issue with the 0n3 turbos are the small exhaust wheels ...... I have looked long and hard at those units and when I wanted to build a big block these came up as well .... I think in a single app or a sbc twin app they would be okay .... but again if your hunting budget turbos the gt45 is a strong contender..........don't be fooled because that on3 is a 76mm its a small turbo and most likely back psi may be high on your good flowing heads and cubes.

also guys that upgrade from a on3 to even a smaller name brand unit pick up hp ..... heck a BorgWarner s366 can support 800hp and its only a 66mm

 

Will the twin gt45's make the power I'm looking to make? I like the idea of cheaper turbos to get started. Then upgrading down the road.