Hey Guys. I am working with an LS7 engine, with 90mm throttle body. Is there any advantage to aftermarket MAF sensors or larger units? If so, what is available for me out there and how would they benefit me? Please advise.

 

Hey Guys. I am working with an LS7 engine, with fly by wire setup. Is there any advantage to aftermarket TBs? If so, what is available for me out there and how would they benefit me? I know I can port my factory one too, what would be better? Please advise.

 

A 100+ mm MAF is likely a good benefit with larger displacement engines like yours. The new Hitachi MAF sensor is small and less restrictive. However it must spaced in a proper tube and in a straight path to avoid disruptive turbulence which would offset all advantage.
I can send you more pictures of what we have come up with.

 

Would love to see this myself please pm me info or post up here

 

Hi. Sounds good, email me the info. What do you have available now?

 

Vararam and Haltech offer a MAF housing ~ 103mm in diameter. I would run a Haltech because they have developed the right MAF scale for it. That is the hardest part about doing it right, is getting the trims back in line with the new maf housings. The LS7 maf is in the airbox, and it is very touchy if you try to play with it.

 

I agree, and we offer the the proven housing, Hitachi MAF with tables and cables.

 

While at the PRI show last week I found these guys. Completely new digital mass air meters.

www.abacoperformance.com

I hope to try them when they are available.

Robin

 

Hi. I am getting mixed answers here...
First of all, what is the deal with this new digital MAF sensors?
What does everyone suggest for stock replacement? Can they provide tuning for the MAF for HP Tuners, is that what you are referring to?

 

Changing to a larger mass air meter will not show any benifits unless your current meter is a restriction.
We worked with many different mass air meters in the past 10 years. Most of our information was gained on an engine dyno or a chassis dyno. With the engine dyno we have the ablity to track fuel flow. On several of the fuel managemnt systems we were able to log the signal from the mass air meter.

A little backgroud first, re raced very rules limited classes. A difference in 5 horsepower was huge in the NA class. We raced both NA with about 380 horsepower at the crank to a limited supercharged class with about 700 to the crankshaft. Both used stock cams as per the rules. The cam effecting the fuel curve is not a factor. Cam was 211 @ .050 with .480 lift and a 115 lobe sep. We could run the NA enngine all day long and the horsepower would not vary more than 1.5 at peak. THe average would change 10 to 15. We felt that was unacceptable

Now remember I got started tuning years before on speed density stand alone systems. The rules for these classes I was involved only allowed piggy back or chips to tune the stock processor.
Once the market develpoed unrestrictive mass air meters I feel that 98% of all race cars can use them.

We learned our fuel flow as well as our input from the mass air meters that we tested varied. The signal was never consistant from pull to pull. We traced it the erratic mass air signal.
We were told that the meters were too "sensitive" to our engine. Hmm stock cam unported heads .....yeah a real quirky engine here LOL. We tried to kill some of the signal rom the meter by relocating or "clocking" the meter in a different position. This had the best result in an increase in our average power.
No matter how much we complained to the companies that made the mass air meters we were told that was a s good as it got. We did some investigating of the methods used to calibrate the meters and realized why we saw the problems in measuring air flow.

The LS mass air units are very close the throttle body opening. I see that when a lot of guys go to wild cams they are changing over the speed density type of tunes. I thought that we had grown past that. Don't get me wrong spped density has it's place but not on a street car (in my opinion).

OK this is getting way to long, we have talked to several companies about a high quality mass air meter. A meter that is calibrated across the entire range without the inconsistancy that we have seen in other aftermarket meters.
We have found that a high quality meter will repeat and give a steady output to the processor. It might not make any more power but the engine will accelerate smoothly through the run. On an engine dyno (water brake) the load is such that the engine is held to a acceleration rate by a programmed servo or a hand controlled water valve. We found the pulls to have cleaner fuel curves and a power curve that was not erratic or full of spikes.
On the chassis dyno we saw the increase in power because the engine was able to pull smooth and accelerate the drum faster. Becasue the drum is less sensitvie to small changes we don't see much improvement in the look of the horsepower curve. Some yes but not as pronounced as the engine dyno.

At this point any mass air meter that you buy will have to be tuned to your engine whether stock or modified IF..... you want the optimum tune. You can bolt one on but it can be on either side of rich/lean.

I am excited about the meter that those guys showed at PRI. We will have several combinations reay to test on the engine and chassis dyno whent they are released.

The stocl LS7 is that flat balade installed in a tube of intake air system. If it is calibrated then it should be OK. If you choose a currently available aftermarket meter be shure to tune to the new meter.
Yes you will benifit from a high quality meter.

Sorry bout the length.

Robin

 

Good info Robin L. You always have good stuff to share. I know the guys with LS2 SS Trailblazers have lots of issues with tunes after cam/heads on the 07/08 more then the 06. This may be a big help for these guy's fighting tunes going so rich with larger injectors & big cams. Thanks

 

Anyone have any better information on the digital units? Do they use factory wiring and computer?