c&l maf...blackvert grady... maybe you can help?

[cbarr300]

well guys, I think I've found out why my tuning's been as off as it is.

When setting up my maf curve I tuned using the curve that eec analyzer had for the 80mm c&l with 55mm electronics (fox) and green sample tube (42 lb injectors. I thought that the person who did the maf before me went with the fox body maf..

well, I ended up looking up the part number and it turns out it's the one for the sn-95..the 70mm one. C&L never put out any kind of number for an 80mm housing with 70mm electronics and a green tube.

So my question is this: Would using the 70mm electronics cause me to run richer or leaner than the 55mm electronics?

Thanks in adv.

 

[Methodical]

I'm no expert with SC but from my readings, it would seem that you will peg that meter. Seems a better meter is either the 80mm or LMAF.

 

[BlackVert]

hmmm ... excuse me for thinking out loud here ...

trying to derive a transfer curve is tricky. i was working on it for my car before it died. i don't think i'll ever know for sure if the tune was what killed it or not, but i doubt it because i blew a ring not a head gasget

but i'd have more peace of mind if i had a maf that had a well known transfer function.

there are lots of variables involved here, the size of the housing, the size of the sample tube, the shape of the sample tube, the electronics, and the transfer function

the sample tube determines how much of the air passes by the electronics. with the same tube, if the housing is bigger, you will go lean because more air is coming in than the computer thinks.

sample tubes are sometimes conical ... bigger in the front and smaller on the t/b side. that causes the air to flow through it faster than if it was straight thru. so if the shape changes, that can cause differences (albeit minor) too

the electronics generates a voltage based on the amount of air flowing thru the tube, the computer reads that voltage and derives the amount of air using the transfer function

the problem i have is that my laptop died over the summer and i got a new one, but i don't have any of my tweecer stuff loaded on the new one, so i can't play with it.

then there is the transfer function and whether the electronics are the same (if they generate the same voltage with the same meter with the same air flowing through it). if we can take those out of the equasion, we might be able to make an educated guess

can you do me a favor? take screenshots of the stock transfers for both the A9L and the T4M0 calibrations?

but i don't think we have enough information right now to figure it out for sure. does anyone know the diameters of the stock fox and 94/95 sample tubes?

i have to go now, but i'll keep thinking about it and post again later ...

lol, it might be safer to just get a lmaf and be done with it