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As I promised earlier, here are the new dyno numbers hot off the press. I'll try to keep my chatter short. I must say that I lied about the amount of boost I was running on the 1ST DYNO SESSION last week when I said I was running 7.5 PSI. It turns out that I was actually running about 8.5 PSI. I recently found out I actually have a 9 PSI spring in my wastegate when I took it apart last night. I wasn't interested in the wastegate spring until I noticed spiking to 9.5 PSI after installing the 3" Cat Back. So keep in mind the old numbers were at about 8.5 PSI and the new numbers are at about 9.5 PSI:
SETUP:
BOOSTING AT 9.5 PSI
T3/T04E TURBO-0.63A/R HOUSING ON TURBINE
2.5" DOWN-PIPE
SPEARCO INTERCOOLER
370CC INJECTORS
JWT ECU
STOCK MAF SENSOR
UNORTHODOX RACING PULLEYS 2-SET
ACT HDSS CLUTCH
JWT 9.5 LBS. FLYWHEEL
SR20DE WITH STOCK INTERNALS IN BLOCK
STOCK CAMS
STOCK CAT
3" MANDREL BENT CAT-BACK EXHAUST
NUMBERS:
Pull 1:
Pull 2: (DYNO JET SEMI-EQUIVALENT NUMBERS):
Overlay of 3" Cat Back and Stock Cat Back:
This one is for GP, you asked for it!
Wideband Output of Pull 1:
Wideband Output of Pull 2:
I am pretty damn pleased to have gained 24 WHP with the addition of 1 PSI of boost and a 3" CAT BACK exhaust. I found out today that the MUSTANG DYNO could simulate power output values similar to a DYNO JET. So I decided to check it out and that is what you see in Pull 2. And I guess it looks like I'm leaning out excessively above 5100 RPMs? No worries, I'm going to swap that 9 PSI spring for a 7 PSI ASAP. Overall, I'm really pleased even though the numbers are going to be slightly more conservative once I go back to a 7 PSI spring. As long as I don't blow it up....so soon anyway.
-saaby
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Red 99 SE-L with: KYB AGX, Ground Control 350 lb/in front 300 lb/in rear, Stillen front STB, Courtesy rear STB, Redline Shockproof, ES motor mounts 4-set, UR pulleys 2-set, Pacesetter short shifter, bent rear to zero toe, Fastbrakes 2-piece 11" rotor brake kit, Potenza S-03 tires, ACT HDSS clutch, JWT 9.5 lbs. flywheel, F-MAX stage I kit with T3/T04E, 370cc injectors, JWT ECU.
yup, bigger is better Are you still on the stock fuel pump? If so, that's most likely the reason you're leaning out. Drop in a walbro 190 or 255 and get a Nismo FPR, problem solved. Also, I'd guess that you are very near the limit of the MAF and injector. Hook up something to moniter the MAF voltage and injector duty cycle. Cheap upgrade would be to get the bored MAF, reprogrammed ECU for 4-bar of fuel pressue for the 370s, and bigger fuel pump.
__________________
Khiem
'96 SE-R.... boost, brakes, suspension, etc... sold
'05 Evo
'05 CBR 600RR
Last edited by spdracerUT : 04-10-2006 at 09:30 PM.
It is motor dependent. Like the Supra guys and 4g63 guys like to run around 12.0:1. No leaner than that. On our motors (DE's at least), they seem to be relatively safe in the low-mid-11 range. If you talk to the rotary guys, they're like 10.0 ah, those apex seals!
So, if I lower the boost to 7.5 PSI, do you guys think my A/F ratio will drop to mid 11's....would it drop THAT much from lowering the boost about 2 PSI? Also, what would you guys recommend as a good wideband. I need to purchase one. Thanks in advance,
So, if I lower the boost to 7.5 PSI, do you guys think my A/F ratio will drop to mid 11's....would it drop THAT much from lowering the boost about 2 PSI? Also, what would you guys recommend as a good wideband. I need to purchase one. Thanks in advance,
-Saaby
I think it will..... I remember Rob Cadle telling me a LONG time ago that the stock fuel pump is only good for around 190whp. He had a fuel pressure gauge hooked up and on a basic t25 setup (no cams, etc), if he tried turning the boost up to 10psi, the fuel pump couldn't keep up (fuel pressure should've been 3 bar = ~44 psi + 10psi from the boost = ~54psi, but the pump was putting out less pressure than that, and that means less fuel which led to lean conditions).
I wasn't in the driver seat, but I saw the guy take it to 7500 rpm. But I think he said he stopped the test at 7000?!...which is dumb since from looking at the curve continuing to go up, I would have made more power for sure!
i still dont see how ur boosting on a stock fpr/maf/ pump
Well, because I gathered that I could as long as I keep it very mild ala boost at 7.5 PSI. Any good widebands you guys can recommend...maybe one I can interface with my PDA?
I wasn't in the driver seat, but I saw the guy take it to 7500 rpm. But I think he said he stopped the test at 7000?!...which is dumb since from looking at the curve continuing to go up, I would have made more power for sure!
-saaby
It's a problem with the Mustang Dyno. They guesstimate your power output by guessing your gear ratios (eyeballing the inaccurate tach at 60mph) and go from there. You may very well have made more power, but we'll never know...
How many people have the AEM UEGO GAUGE WIDEBAND. Has anyone hooked it up to a laptop through an RS232 interface....what software do you use to do datalogging and track RPM so you can see the A/F ratio at all RPMs???
PLEASE upgrade your fuel pump and maf before you spend money on a wideband. Actually, do it before you do anything else.
[edit]AND INJECTORS[/edit]
C
Thanks for your concern. But after talking to JWT, according to them its not necessary. As long as I'm not maxing out the MAF and 370CC injectors. Running at ~7.5 PSI, my injectors where at 88% and my MAF was at 4.7 volts. I plan on purchasing a wideband for a reasonable price since it will come in handy when upgrading my setup down the road. I will STRESS again that I just want to start with a mild boost setup to begin with, and upgrade LATER.
Are you still on the stock fuel pump? If so, that's most likely the reason you're leaning out. Drop in a walbro 190 or 255 and get a Nismo FPR, problem solved. Also, I'd guess that you are very near the limit of the MAF and injector. Hook up something to moniter the MAF voltage and injector duty cycle. Cheap upgrade would be to get the bored MAF, reprogrammed ECU for 4-bar of fuel pressue for the 370s, and bigger fuel pump.
ah, those apex seals!
