i know ford has a whole crapload of mass air sensors that are larger and flow more air than stock, but i can't find any for the 3rd Gen. cars.....i know Granitelli makes them for the LT1 and LS1, but what about us 3rd gen guys? reason being i just put on a SLP cold air kit and i'd like to open up the mass air a little bit...any help or sugguestions would be greatly appreciated...thanks!

 

As far as units that are larger than stock, there isnt a single thing in the aftermarket. There is the replacement Wells maf, but its still a stock diameter MAF but supposedly flows alot more, almost equal to what a de-screened and fins removed stock MAF will. And then of course theres the ECM that isnt helping the situation any either, its still limited to reading 440ish CFM at the most.

 

so what could i do about that......put in a performance chip??

 

A performance chip wont help. So far, theres no reasonable way around the limit in the ECM.

 

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440ish tops by the ECM!!!???...please tell me your joking!
What about the prom burners on this board?
How can I expect to get high hp numbers if 440ish is all the ECM can handle?

 

Nope, not joking. The max the ECM will account for is 255 gm/sec, you'd need to convert that to CFM but IIRC its in the 440ish range. People have had ideas of 2 mafs dancing in their heads, and effectively lying to the ECM, but I'm not so sure thats such a great idea. The resolution of the tables for the MAF on the prom are not exactly closely spaced as it is, and that would just make it 2 times worse.
There is a way to increase fuel past that limit though, but you have to make changes in the prom to do it. Keep in mind that there are also some very quick MAF cars out there, so its very possible to make power with one.

 

At what point should you transfer over to speed density?

 

Yeah, that was me with the "dancing ideas". It turns out that a MAF ECM will simply utilize the MAF signal as part of an equation it uses to calculate the load variable (LV8) and that it isn't actually directly measuring the airflow, then compensating for it.

The best way to stick with MAF is to see when the MAF maxes out (what RPM) and then add more fuel manually via the PE tables at higher RPMS. I haven't done it yet, but others have.

Depends on what you want...

 

Well it depends on who you talk to. If you talk to some people whos names I wont mention, they will tell you that you should ditch the MAF setup as soon as you buy your car. IMO thats a stupid idea, and I will explain why. There are lots of cars running 11's and 12's with a MAF setup and custom tuner chips (mostly ones from TPiS, which if you look around there are many that are very unimpressed with their programming). So, how much of a problem is it really? Does it make sense to swap to SD to pick up maybe 10hp? Its not cost effective at all if you are like me and dont have a bunch of spare parts laying around that you didnt pay a dime for. I figure it would cost me a minimum of $150 to swap to a SD setup. I can think of alot better things to spend $150 on. Chances are, it would end up costing more than that. And people complain about freeing up only 5hp or so with an underdrive pulley and having to pay so much to do it. Gee, I wonder if those are some of the same people that suggest a SD swap?

 

For me, the answer will be when I am maxing out the MAF...although it shouldn't be too tough to manually compensate above that max-out RPM...

I understand exactly what you are saying...I don't really WANT to switch. It would be different if I was converting to a TPI setup from a carb, then I would go SD right away, but as it is, I will see what my car will need.

BTW, I am starting to burn my own chips too...

 

Madmax,
AS you can see from my sig...I have two cars. One I spend cheap, sale parts from other cars to buy parts, etc. My 5 speed I am willing to pay the price. With my 350/Auto Daily Driver car I believe I can get 12s eventually without a whole lot of hassle (383 build up).
For my 5 speed I am gunning for low 11s. Haven't decided what motor route to take yet...but the MAF limitation concerns me. I have read, or thought I read, where tuning was easier with MAF. Should I go ahead and plan a change to Speed Density (looks better anyway)...or is the MAF the better way to go? What about forced induction through a MAF...possible?

 

Yes, adjusting the Air Fuel ratio above the max limit of the MAF is possible and works very well...... It will take some tuning to get you there though.... And FWIW, the table for tuning the air fuel ratio above the 255 grams/sec level is the: P. E. %change to fuel/air ratio vs. RPM and it allows tuning up to 6400 rpm.

I really have to agree with madmax on the cost effectiveness of the SD swap (or lack there-of).... If you know what you are doing with the PROM you can make virtually the same power with either system.

Laterzzz,
Matt

 

I ordered my wells MAF from World Discounts on Friday, and it came in yesterday. Considering that there was no mail on Monday, that was impressive.

 

Max,

That's almost correct. If you place teh two units side-by-each on the bench and throw the calipers at them, the Wells unit is 3mm larger in the small direction, and about 8mm larger in the long direction (it has a little bit of elliptical shape in the housing). If you talk with the engineers at Wells, they won't tell you that it flows more at the same pressure differential, since they designed it as a direct drop-in replacement. The flow test on a bench tells otherwise. Unfortunately, the bench I used to have access to was only calibrated to 700 SCFM, and the Wells unit didn't hit the 0.1" SP at that flow level, whereas the stock Bosch unit (complete with dead hot wire) flowed to about 580 SCFM at 0.1" WC/SP. The sad part is, as you say, the ECM firmware limit is 255g/S, and tuning is the best way around that.

 

I dropped that new wells into my IROC last night, and now it won't start.

I don't think it's the MAF though, because for the 1 minute that it did run, it didn't throw a code, and the car wouldn't start even with it unhooked. To rule it out, I'm going to stuff the old MAF back on there tomorrow.

 

Jim

keep us updated with that as I'm about to order one of these imfamous Wells MAFs.

Robert.

 

I'll be sure to keep you all updated. My situation is a bit unique, because the stock 85 MAF works differently than the 86-89 units. People seem to have been able to interchange them without problems. I don't think my MAF is the culprit, but I can't rule it out yet.

 

i turn 460 hp out of a stock mass air flow sensor on an 86ta

 

RMK, I just wanted to let you know that I put my stock MAF back into the IROC and it still won't run, so it's looking pretty positive that the new MAF wasn't the cause.

 

Thanks Jim. I'll order mine next week when my salary comes through.

Sill interested to find out what's up with your car though. I like electronics and computer controlled fuel injection, but only when it works.

Regards

Robert