Help with prepping GT for tune...

Unreal281 said:

2. Typhoon Satin intake manifold (3 Peice)

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Kilgore Trout said:

Changing MAF requires a tune and that is most likely where your power came from.

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Yellow2002GT said:

I disagree with the MAF.....a less restrictive housing can benefit alot! I would go either pmas pro m 80 mm with the power pipe.....I tested about all of them and with that set up it netted 13 more rwhp than the bbk with stock meter on a custom dyno tune for both and about 18 rwhp over the stock intake tube and meter! It is restrictive as hell! I have a similar setup going in and am unsure about the typhoon! All the tests I have seen so far havn't been impressive but they been without a dyno tune and on supercharged applacations! Without adjusting the tune the intake really isn't gonna improve. The A/F ratios on top end richen un quite a bit so I am waiting for some more testing with the intake and a before tune and after tune comparrison with both intakes! The potential is there.....just need more rpms and a good tune to match!

"ED"

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jstreet0204 said:

The stock MAF is not a restriction period. Any gains you made were from the tune, not the MAF. And before recommending the steeda fuel pump, you should do a little research, as there are MUCH cheaper alternatives that will flow just as well or better for right around $100. In the case of the original poster there is no sense in him spending money on the MAF, injectors, or fuel pump, as there are no gains to be had with his current mods. I would suggest saving that money and the money for the intake and investing in some ported heads.

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Yellow2002GT said:

LOL if you read my message...you would have seen that both were dyno tuned to the fullest capacity! I dyno tune my car alot......after even minor mods.....believe it or not the stock meter may handle the flow....but the design of the pro-m 80mm maf is light years above any other! People add bolt ons and dump money in parts all the time but never get the desired result because they don't dyno tune their combinations! Just let me say that a 4 in intake with a great breathing maf will net big gains in the 3000-5000 rpm range! Most people judge hp by peak hp numbers but the secret to make the 4.6 faster in improving the entire rpm range. Ford puts way to much timing down low in the 4.6 from the factory and it actually loves less timing in the low rpm ranges! Most tuners tun the top end a/f's and small number are gained. I use Dan at Pro-Dyno in Charlotte and he will fix all the timing and a/f's throughout the power band! Lets just say I wasted thousands of dollars with hand held tuners and equipment and found that maf/ obdII cars need to be dyno tuned....even from mild bolt ons!

"ED"

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Ed Clark

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MAF replacement
Folks,

I've been looking through the threads here and have noticed a trend. This has been discussed before but I'm going to be more blunt.

This trend is mass air meter problems from needlessly changing out a perfectly working stock MAF sensor.

The real problem is that these problems are owner induced almost 100 percent of the time. They start the instant an aftermarket meter is ordered and installed for a car that doesn't need one.

The worst culprit is C&L (sorry C&L). Folks buy these cause they are cheap and appear to be easy power gains. I recently had to retune one of these meters that was installed on a near stock 99GT and had the full C&L treatment on the intake side. IT WAS 35% LEAN ACROSS THE ENTIRE RANGE. This is not uncommon.

ProM meters are better but can still be commonly far enough off to make the car run poorly. Even meters calibrated for stock injectors with a stock curve can vary from stock specs enough to cause issues. Also the exact location and orientation of the MAF can have great affects on the mixture that aren't the MAF sensor's fault. The larger the injector calibration on the MAF sensor the greater the likelyhood of the error.

The computer is capable of pulling about 20 percent fuel to correct rich and adding about 30 percent to correct for lean. Now even though the computer can learn and make these corrections it doesn't mean that it does it good enough to make the car run under all conditions correctly. It can't. It's said that power gains from a MAF swap come from leaning the mixture. But computer is going to try to correct any lean mixture based on O2 sensor voltages. In stock form the computer will even apply these trends learned to WOT.

Then say throw in a mail order chip or a self tuning device and your now hosed. It will run like crap. So a custom tune is then required to reestablish a correct Mass air transfer curve. Once that's done where are you going to get the power gain from? In fact even once corrected it's probably not as accurate as the stock meter.

My suggestions are:

1. Don't buy an aftermarket MAF as a POWER MOD. You buy one if you need to meter more air for your combination. Mainly supercharged setups. I've yet to see a NA 2v peg a stock MAF. Close but not yet. Maybe Ken will.

2. While most tuners can recalibrate any injector/MAF calibration combos try to keep MAFs calibrated for the injectors in use. This allows for simple troubleshooting by simply removing custom chips. The car should still run "OKAY".

3. Keep the screen installed, it's there for reason and it's not trapping debris.

4. Try to only use kits that mount the air filter directly to the front of the MAF sensor.

5. I've never seen an aftermarket MAF that didn't need to be retuned to some degree no matter the calibration. If you have a an aftermarket MAF you probably need a custom tune. If you don't your one of the lucky few.

6. Don't modify the stock MAF. And that means don't cut out the post. It's there for a good reason, air flows around it just fine and removing it WILL affect calibration of the meter. Thus causing the same kind of issues as an aftermarket MAF sensor.

Bottom line is the MAF isn't a restriction for large percentage of people. The Ford meters are more consistant than any aftermarket meter that I've seen so why spend money on them you don't need to.

Ed

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