jeff gillings

I had my car dyno tuned and programed at Speed Inc. and I am wondering how my numbers compare. My Max. HP is 345.6, Max Torque 359.2.

Camaro_Maniac63

I guess those numbers could be a little better, but numbers don't really mean anything. Take her to the track and see how she does, and then let us know. Good luck.

Kuma

Sounds ballpark for what you've got

Kuma

Are the heads ported? Supposedly will give you another 10-30 hp depending on flow.

jeff gillings

The heads are stock Lt4 so is the intake no porting. Speed Inc. told me those were real good numbers. They actually took the 30# injectors off that I had installed and put the stock ones back on saying that the stock ones are plenty. They also put my stock MAF sensor back on instead of the Granatelli saying it is more consistant.

predator

man i thought lt4 was good for 420 hp are you sure you got the hotcam because those numbers sound like a regular lt4

Camaro_Maniac63

Yeah, but they are good for 420 at the FLYWHEEL, which is roughly what he makes. Plus he has a high-stall converter.

NVetro

Did you install the LT4 Conv. Kit yourself? I thinking of getting one.

predator

doh i am stupid for got RWHP 15% drivetrain loss by average

LT4C

I wonder if those are the number I should have if I get the 52mm tb. I currently dyno with my lt4 conv. 329rwhp. with my stock tb.

jeff gillings

The 345.6 is RWHP. so it is about 405 HP. at the flywheel. I have talked to people here and they all say that GM's claim of 420 to 430 HP. is a little far fetched and that it is under perfect tuning conditions. I even pulled the motor line honed the cylinders put all new bearings throughout, piston rings, Comp. roller lifters, pushrods, new opti-spark, and balanced the short block then put the conversion kit on. I pretty much freshened up everything. I don't know what more GM did to get their numbers because with shorty headers and stock cats. I only dyno'd at 317 RWHP. I didn't get 345.6 RWHP. until I put on the Hooker long tubes and Mufflex Y pipe which gave me an extra 28 RWHP.

96 TA

If you had an M6 youd be putting down somewhere near 355hp right? So for an A4 thats good! Im no expert but I think you were better off with the 30lbs injectors! I haven't read your sig yet but maybe a FPR and a better fule pump might help out???? Don't be disapointed! GM advertised up to 425fwhp not rwhp!

PhoenixCIS

ive got the lt4 heads and intake. im gettin them ported and polished this week and we'll see what i can make.

u really need headers and cai or ram air to take full advantage of the LT4 conversion from what i hear.

Kuma

You really should increase the injector size so you don't have the stockers running at 100 percent duty cycle whenever you floor it.

ur2slow

Those numbers look right for an auto. I don't think you need bigger injectors yet. My factory LT4 came with 24#er's not even the 28's that the vette got and my duty cycles are fine. I think with mustang dyno to dyno jet comparison I am rate around the 435 fwhp range.