OK gents, hoping to get a little guidance from you...

I have an LT1 motor from an ex-cop car Caprice. I guess that means it had a 3 inch MAF. The motor is now a 383 with AFR 195 heads, and LT4 intake, and Comps 503 cam. I put a BBK throttle body on it, 52mm.

My question is this:
Should I use the stock MAF, try to get an F-body MAF, or go for an aftermarket MAF? What are the advantages for each option?

Thanks for any input,
Jim

 

Use the stock MAF. I dont recommend getting an aftermarket MAF tuning issues are a bitch then I made 632rwhp with my stock maf

 

Was that a stock 3 inch B-body MAF, or the 3.5 inch F-body?
Maybe even the smaller 3 inch one that I have will breathe well enough for my motor? I won't be any where near your power level 396D1SS....

 

B-body MAF maxes out at approximately 320-330 rwhp. It still possible to tune the car using power enrichment tables but a 3.5 f-body MAF is a better idea.

 

since when was the Fbody maf a 3.5" unit??

last i checked it was 75mm...which is 1mm shy of 3"

even the aftermarket SLP 85mm maf is not quite 3.5"

stick with the stocker

 

I think the metric measurements probably apply to the LS1 motors, right?
I was talking about the LT1s....

 

It doesn't matter what you are talking about, the conversion from millimeters to inches is still the same. My 94 had a 3" (or 75mm) MAF sensor.

 

Oh really, I thought there was a different conversion factor for millimeters to inches when you changed engines.....

What I was trying to say is that I think that the newer engines GM uses a lot of metric designations for...like a 4.8/5.3/6.0 L engines versus the old english measurements like 305/350 Cubic inches. When I read 75mm MAF, I think " this is for an LS1." When I read 3.5 inch, I think "old school motor stuff" meaning not as new as the LS1 style of motor.

If you had a 3.5 inch MAF, I guess you could call it an 88.9mm MAF if you wanted too....or maybe you could call your SLP 85mm MAF a 3.3464566 inch MAF....

 

Since when did F-body's get 3" mafs? My stock 94 had a 3.5" and the replacement I bought from a junkyard F-body was also 3.5". Did I miss a memo or something???

Also, I know this forsure because one of them is sitting right next to me and I just measured it.

 

Yeah MyShibby, you missed the part that said Caprice and B-body. The question that was posed was whether it would be worth it to upgrade from the 3" b-body MAF to a 3.5 " F-body or an aftermarket.

Most of what I have read so far seems that an aftermarket MAF creates some headaches and plenty of power can be made with the 3.5" ones..

 

Oh, I did not see the Caprice part. That explains a bit.

I remember reading a post of someone putting 830rwhp through the stock maf with the screen and fins, but yet that had a turbo on it too.

The reason I have two mafs, is from me porting one. I ported it thinking I would gain something. All it did was make the throttle response and rev faster, also lost about 1-2 mpg. Aftermarket ones are not really worth the way overpriced money.

 

That could simply mean your tune was not as good as it could have been.

I think it was truedualsWS6 who had his car mildly cammed car dyno tuned with the stock MAF and the GMS the GMS netted him 2-3hp at over 300RWHP. At $100+ per HP it is foolish at best for anyone to recommend it.

Again I believe you felt a power gain, but can also explain it as you simply needed more tuning and had you spent the $300 on that instead you would have seen at least as much gain and likely more. Once you understand exactly what the parts are doing and how they work I am sure you would agree.

My opinion the stock f-body sensor is the way to go as far as the 3"/3.5" thing I am not fressed yet so I am not going out in 20degree weather but I have both sensors on hand along with a Granatelli a friend bought before he researched I can compare later but the b-body sensor is smaller than the f-body and the GMS lacks the wing in the middle that both the others have. I have no doubt the GMS will flow more because of this, it is the calibration and wether additional flow over the stock f-body one I feel are questionable.

 

USe the stock one, then borrow or buy a Fbody one. Swap them out and see if anything changes. If not, sell the fbody one for the same price you paid, or return to the person you borrowed it from. If it does work better, keep it (unless you borrowed it, then give it back and buy yourself one )

-Shannon