Quote:
Originally Posted by MMGT1
Any progress B? How's the set up working out bud?
|
Quote:
Originally Posted by unchained01
i have no doubt he will get it fine tuned eventually !! post up when u get a chance
|
Thanks for the support, I appreciate it!
I have good news and bad news on these modifications:
The direct connection with the large TB and MAF appears to be a success. I measured about 3 inHg vacuum less pressure drop at the supercharger inlet, compared to a 65 mm TB ( ported stock) with a 3 inch curved transition tube from the MAF. That translates into about 1.5 psi peak at WOT, similar to going to a (0.1 in) smaller SC pulley. Keep in mind I have a 2.0 inch SC pulley installed, and before the mod was reading about 11 psi at the upper intake.
The MAF frequency and lb/min. were also an order of magnitude higher across the board. I did several tests on the street, and logged the changes in fueling seen by the PCM -- Injector Duty Cycles (IDC) and Injector Pulse Width (IPW) increased, and narrowband O2 readings stayed in a good range, no Knock Retard was generated by the PCM. I was now maxing out the 36 lb injectors at 12.0 Target AFR, and reset it to 12.5.
I went down to the track Saturday the 15th, (chomping at the bit, as you can imagine) On the first run, I did a good solid burnout, but the starter motioned me to halt and wait, I hit the brakes and waited a while, but then backed up and did another aggressive burnout (which ain't the best thing for a tranny
). I had a pretty good launch, no wheel hop, but out of first gear it hit the rev limiter, no WOT shift to 2nd gear .
. The scanner threw a TPS code, and for a while I had some hope, so I put in a new TPS. Another run, same result, can't go higher than 1800 rpm in 3nd gear. So the search for a good local trans shop begins, and the necessary PITA demodding to facilitate a major repair. ( I can hear it now, "We ain't gonna guarantee this."
)
(edit: still clinging to hope, a few more things to check out)
The other "good news" is this is an easy mod to try with the Magnacharger kit, or maybe extreme N/A builds, and might work just as well with a 65 mm TB and a stock MAF, depending on how they interface and what boost level you run. Also note, as run at the track, the air filter is bypassed, and just a short flared piece installed at the MAF inlet. You only need a vacuum gauge with an expanded scale to test the need for an upgrade.