PDA

View Full Version : Maf MaxOUT and other issues



odd boy
October 22nd, 2010, 08:29 AM
Hi everyone,


Car is vette 99 with 408 engine, H/C, F1-A procharger 14 psi.

Look at the log of this car, has a lot of stuff to be corrected:


Fuel injectors needs to be replaced with a higher size " will go for 80 vs current 60"
Mass air maxes out around 4200 rpm, will go for lingenfelter 100mm vs Z06 "OME# 25168491". Anybody tried it before, please advise if it good or not.
Fuel pump needs to be replaced, from dyno graph "will be attached later" fuel pump fails to deliver the required fuel. Racetronix with KB BAP, still I am looking for good replacement, door is open for ur suggestion.

Thanks

9284

swingtan
October 22nd, 2010, 09:17 AM
LOL.... It always makes me laugh when i see IDC > 100%

Are you open to running a SD tune? That would remove the MAF issue and also get past the 512gm/Sec limit in the OS.

Simon.

odd boy
October 22nd, 2010, 08:43 PM
LOL.... It always makes me laugh when i see IDC > 100%

Are you open to running a SD tune? That would remove the MAF issue and also get past the 512gm/Sec limit in the OS.

Simon.

Actually, this car was brought from the states and was built up by MTI before final closure. We refreshed the engine, I got shocked when I saw the MAF maxed out, I thought the car is perfect since it was built by experts. Any ways, I am open to SD, but prefer MAF. Does OS give window for more than 512 gps?? what is the limit ??? can the PE take care when more fuel is dialed? or no fuel will be added when the maf reaches the limit??

Do u have any idea regarding a good fuel pump for vette (97 - 02).

swingtan
October 22nd, 2010, 10:10 PM
Once the MAF is maxed out ( 12000 HZ or 512gm/Sec ) you will get no more fuel as the PCM doesn't know that there is more air flowing into the motor. I don't know if there is a similar OS that allows for more air, but with what you have, you are pretty stuck if you keep the MAF. You may be able to get an after market MAF that gives a lower output frequency, but you still need to manage the 512gm/Sec limit in the MAF tables. Really, I think it would be easier to go SD and forget those limits all together. I don't know if there are other limits that may get hot though, I just know all the guys here toss the MAF as soon as they start getting serious, even NA guys will go SD.

RE: Fuel pump, again around here, the Bosch 044 is the choice. With serious set ups though, a surge tank and dual pumps tends to be used. The stock pump feeds the surge tanks and the dual 044's feed the injectors.

Simon

odd boy
October 22nd, 2010, 10:25 PM
thx for the advice, will go mafless.