What is your MAF at idle?

[ZR1TR]

I have KR that comes and goes with and without alky. I have been trying to chase done the problem. I read a thread on here about a bad maf causing sporadic KR. On the SM2.1 I never see more than 5 at idle for the AF reading. Could my MAF be bad? I don't have any of the tell-tale tip in stumble, and I have tried the tapping method to test the MAF with no difference. So what are your guys MAF at idle.

Thanks

Jonathan

 

[strikeeagle]

4 or 5.

What do your MAF values look like under part throttle acceleration? Full throttle acceleratiopn?

 

[ZR1TR]

I.m not sure. I have been monitoring knock and o2s so closely I haven't looked at the af at WOT. At lunch I will fill up the alky and make a WOT blast paying attention to the AF. It shouldn't change with the alky on or off right, because it is a measure of air grams only. Right? Can you give me an ballpark figure of what they should be at part throttle. I know WOT is 255.

Thanks

 

[Jbenn911]

5 or 6 here..normally 5, though

 

[strikeeagle]

What you're looking for is a reasonable transition as you SLOWLY accelerate and decelerate. Drive around a bit. No need to hammer on the car. Drive as you normally would. If MAF values start hopping all around I'd be suspicious of the MAF...

 

[ZR1TR]

Well I took it out at lunch and the readings correlate with the throttle applied. However I notice I could never get it over 226 at WOT. Does this mean it is the MAF or say could vacuum leaks be responsible.

On a side note, the static FP is set at 38 psi, everything else is stock, except for the 3000 stall converter, and Blue Top 36ers. Does the FP seem too low? With the stock injectors I was running 45 static with a thrasher chip. The reason I tuned it to 38 was BLMs were way low.

 

[XLR8]

38 does seem a little low. Stupid question - you have a chip burned for the blue-tops right?
My MAF reading is usually a 5 when in park and 5 to 6 when in drive. Your MAF not going to 255 could be serveal things, but I'm betting that you are not moving that much air. I don't think that with a stock heads and cam motor with the stock turbo at 15# of boost you are going to hit 255. I didn't hit 255 until I had a TE-44 and running high boost.
Maybe someone in your area can let you use his MAF for a few miinutes and then you can see if your MAF is bad.

 

[ZR1TR]

Yeah Im running a Modern Muscle Street Chip for Blue Tops. From what I've heard it is old technology and there are better chips. I suspect that it has quite a bit of timing even for a street chip.

I'm going to do a couple things. First I'm going to try to borrow a know good MAF, it shouldn't be that hard, Amarillo is probably the TR capital of the world (per capita).

Second I'm going to look for a newer chip.

I know that turbotweak is the way to go as far as custom chips. What else is out there for 36ers.

Thanks for all your help.

 

[XLR8]

I use chips from Joe Lubrnat at PTE. I also think you can get a thrasher for Blues.

 

[quikv6]

Maf readings

Just for info...I had low AF readings at idle (3-4). Blm was in the high 150s or pegged at 160@ idle, and i was getting kr under boost. . I chased vacuum leaks forever...until i swaped the MAF...blms went down to the 120s, and most of the kr was cured. So....make sure your blm are ok. Good luck
Chris