View Full Version : KA-T Dyno results @ 12psi.

05-26-2005, 09:40 PM
Hey guys, I could use some input on my dyno from last night. I've had my KA-T up and running for about 3 months now.

All runs were made at 12 psi on 93 octane with boost tapering off about 1 psi towards the end of the run to ~11psi. It ran extremely rich after 3500 rpm with the A/F going all the way down to 9.5:1.

I know that JWT tunes run rich but 9.5:1 seems rediculously rich. I was looking at other graphs that have been posted with the same tune (JWT ECU, 50lb injectors, Cobra MAF) and they don't run nearly as rich as I do.

I pressure checked the entire system before and it did not leak, timing was set to factory 20* BTDC and fuel pressure was set to 4 bar. I know there is more power to be made by at least getting the A/F back above 11:1.

My setup is as follows:

Stock '95 KA (~70,000 miles)
JWT ECU (4bar program)
top feed MSD 50# injectors
Cobra MAF
Walbro 255 lph fuel pump
1G DSM BOV re-circulated
Johnny Race Car intercooler (25 wide X 7.75 tall X 2.75 deep)
Stainless steel log manifold
T3/T04E 50 trim, stage III wheel, 0.63 A/R compressor and 0.82 A/R on the turbine.
Full 3" exhaust, DP and catalytic converter
Tial Wastegate (open dump)



05-27-2005, 01:33 AM
get a s-afc2 and clean up the fuel ... also if you have a JWT ECU ... i would put the timing at 20 degrees and let JWT do its job ... also check through the s-afc2 your Knock ...

05-27-2005, 07:00 AM
Your setup is VERY similar to mine...except I'm running JWT cams and a little better fuel trim (have you pressure tested everything? Look like a small boost leak, maybe?)

Also, your cat converter is probably robbing you of a liltle HP up top.

Anyway, I did ~298rwhp @ 12psi, but the cams help bring the power out to ~6500rpm or so.

I'm impressed with the spool with your .82 A/R turbine...I get full boost by ~3700-3800 with a .63 A/R...your at 12psi by ~4000. Good stuff.

Anyway, pressure test it...you'll know if you fixed the leak if your boost holds out to redline....mine can hold 12psi to 7000 EASILY...yours definitely should.

- Brian

05-27-2005, 05:25 PM
You may be right, I may have a tiny boost leak in the system that doesn't open up until full boost. Looking at the boost vs A/F graphs it looks like the A/F starts dropping at the same time the boost starts falling off.
hmmmm...I'll have to look into that this weekend.