Predictions On My Numbers?

99Blownstang

Member
Feb 15, 2012
107
6
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My car is currently at the shop and should be getting put on the dyno tomorrow. What numbers do you think I will be putting down?
1999 mustang gt
4.6 stroked to 4.75
9.5:1
Stock 2v heads and cams
2.1 KB with 12psi
60lb injectors
Tr6 plugs
KB cold air intake
75mm tb
90mm Maf
Stock manifolds w/ x pipe and flow master 44s
 
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Talked to my tuner today and I have some good and bad news. Bad news is I'm only making 5psi, hoping its just the bypass not closing all of the way. Good news is at 5 psi it put down 365whp and 390tq
 
BTW, 7 more cubic inches is not going to drop boost by 3lbs......

I agree. But it should drop it a little bit. And depending on his geographical location and weather, it could be hot enough that it's not seeing all of it either. Could also explain the slightly lower than expected numbers. My car will lose 2ish pounds of boost, and every bit of 50 rwhp, in 90 degree weather vs. 50 degree weather, and if his location is like mine right now, it's HOT as crap.

OP, I guess I'll I just wait until I see the graph, but there's plenty of things that could cause the numbers to be less than expected. Hot weather, for one. A stingy dyno (the dyno I go to normally reads 5ish % lower than others in the area). An overly-safe tune (super rich AFR or lower spark timing numbers). A heat-soaked blower (this is a BIG one for positive displacement blowers; I've seen an 03 Cobra go from 480 to 450 on back-to-back pulls because the 2nd pull was so heat soaked). Lots of things, really. The best measure of how much power it's making is to see what it traps in the 1/4 mile, weigh the car, and record the density altitude at the time of the track run. THAT is the only true measure of how much power the car is making.