Power on on3 turbo

[koopman11]

My motor is going to be back from the shop soon with rods and pistons and I'm putting an on3 turbo on it until next winter when I do a pte7275 and 4r70 swap. I'm going to be sitting at around 10.3:1 compression, stock heads and cams, and on3 70mm .63 a/r turbo. My question is what wastegate springs do you guys think I'll need to make around 550 whp or so, on a mustang dyno. For reference on the same dyno it only put down 274/283 with intake, exhaust, and dyno tune. And 366/444 on a 100 shot. I'm more concerned with torque than hp really due to 5r55s. In my tranny I put in tci input shaft, intermediate servo, ptc custom boost converter, and big tranny cooler. I was thinking either 12 or 15 psi springs and just letting it make what it makes. I'm hopeful of the tranny holding 550+ ft/lbs on this dyno, as people have made that on a completely stock 5r55s. The motor can handle whatever power comes

 

[retfr8flyr]

I don't know what the wastegate springs are for the On3 kit but Tial makes springs for 13 psi in various colors, depending on which gate you have. I think the 13# spring would be the best for longevity with your 5R55 and should make about the HP you want.

 

[koopman11]

Thanks! I was thinking between 12 & 15 so that would probably be good.

 

[roberts]

I would buy a different turbo man. I know some ppl have had good luck and some have had bad luck.

 

[koopman11]

I would buy a different turbo man. I know some ppl have had good luck and some have had bad luck.

Yeah man I was planning on buying a precision next winter when I do 4r70, but I'm considering just buying it now. I know some have put down 800+ but others have exploded much sooner.

 

[roberts]

Contact Bobby Smith and s&h and get a comp for cheaper than what u want and do the same thing.