OK all you ECU tuning guru's, I have a couple of questions.
Being new to the whole socketed ECU/WB/modified engine game, I've done a lot of reading and need a little input.
I took the Scamp for its first real drive last night since finishing the engine install. For those who haven't read my thread, I converted it to a 2.5 TII setup with +40's, a ported head with +1mm valves, 2 piece intake, FMIC, AFPR, Walbro 255 in the tank, 3 bar MAP, and a stock Garrett turbo w/ turbonetic 2.5" SV. Force Fed Mopar did the tune for it from a known tune he was running. Ran like a scalded dog for the first 15 minutes until I stopped. AFR's on the wideband looked good, everything was running fine. Never shut it off, then took my nephew for a drive. It seems like it went a little "soft" when I drove him around. Not bad, but not what it was. AFR's were staying in the mid to high 13's. Came back, shut it off, and hung out for about 20 minutes, then drove it home. AFR's are high 10's- low 11's when I punch it, but cruising, they seem to vary a lot more than I think they should, and the engine has a slight "surge" when cruising. Running 65 mph down the highway, the AFR gauge was bouncing around from about 13.3 up to 15.5. I know the ECU constantly adjusts, but should it vary that much?
I have about 48 psi of fuel pressure at idle, and with vacuum unhooked, it goes up to about 52-53. Sitting there idling, the WB is showing right at 14.7, so I'm not rich at idle. I do need to remote mount my gauge to see what it's doing under load, but with the AFR's I'm getting at WOT, I assume it's raising fuel pressure OK. Right now I'm running minimum boost(about 6-7 psi) while I break it in.
I am running an Auber Instruments 3 bar MAP sensor that was suggested on a thread here. A friend of mine was running one as well, and he was getting some odd AFR's. Said switching to a genuine GM 3 bar MAP fixed it. Maybe that's my issue? Not real sure, and I don't want to throw parts at it.
I checked, and I do not have any codes. The ECU is happy.
Hoping for a little wisdom from those of you who have gone before, and know a lot more about this stuff than me...
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