Hi guys, I've heard that the mass air flow sensor is more precise and is more technologically advanced compared to the Speed density sensor.

What I'm wondering is why my 88 Vette has a mass air flow sensor and why I've heard that 89's and 90's have the speed density sensor.

To prove my point, the LS1 engines are using mass air flow sensor.

Unless I"m mistaken??? :confused:

 

There has been a lot of debate on this subject, talk to Jesse (ski-dwn-it).

 

the mas is more accurate and more tuneable friendly too do you think gm went back to the mas for there health i can tell you this it isnt cheap :cheers:

 

The '85-'89 L98 used MAF and the SD started with the L98 in '90 and continued into the early LT1.

Indeed the MAF should be more accurate as it directly measures the mass of air flowing into the engine. I suspect that the early MAFs were much more expensive than the later MAP sensor used on the SD systems; later as technology improved (how many PCs existed in the early-late '80s) a cheaper MAF technology became available.

We look at the performance aspect but I'm sure The General is driven by many other considerations...look at the C6...like ROI.

 

What do you meen Like ROI?
is the C6 going back to SD?? :confused:

 

Return On Investment. Boardroom speak for profits. Quarter mile times and skid pad G force numbers aren't the main motivators at GM. Costs and meeting government requlations keep more execs awake at night than ETs. With the cost associated with a MAF, they would much prefer to use the speed density (SD) system. Emissions and fuel mileage make the mass air flow system a necessity. Pre 1985s were SD.

RACE ON!!!


[Modified by CFI-EFI, 3:38 PM 12/13/2003]

 

Both the systems are very ample in their function.

If you have SD, then stay with SD. If you MAF then stay with MAF.

The reason for the debate is some are lead to believe that gains are going to be seen from a switch from MAF=>SD.

Both have their demons.

At the end of the day, GM has gone back to the MAF, the more expensive of the two sensors. Anyone that knows or has supplied GM with product knows all two well that if GM can save a penny by using a different/equal sensor, they would. Sooo I can only conclude they have a reason for moving back to the MAF, after only a few short year with SD. I can speculate that it do to the MAF ability to "adapt" to changes better. In the sense, no pun intended, not to mods that an end user might persue, but to natural wear and tear that cars experience. The one downfall of the SD system is its inability to "adapt" for an aging car that might some day develope a vacuum leak, warranty claims were I can only suspect MUCH more with the SD system. Think about how the system operates, one broken small plastic vacuum line and the entire system is thrown into a loop.

The MAF system however, is very adapt, without sacrafising accuracy. If I was calling the shots on the two systems at GM, I would vote the MAF into operation ahead of the SD. As even with my own cars, I want the system that I need to worry the least about, and is not going to cause me a headache. Even through all my extensive mods, the MAF system has been all but transparent. Can the SD users say the same, that have even just changed intakes....Nope.

:cheers:

 

ROI==Return on Investment...i.e. the bean counters rule.

I'm not sure but believe the C5s use a MAF (and maybe also a MAP) system.

No, I just meant that the C6 seems to be an "evolution" with more care to bells & whistles that will "sell" as opposed to performance and heritage.

As I've said before, it's too bad they don't make the Caddy the posh sporty car with a good level of performance for the people who just want a posch car, with all the air bags & amenities, and put the Corvette budget into keeping it the world class performance sprots car with killer looks.

 

Stef, MAF is more effiecient and more precise than a SD car. It is more adaptable to changes and does not require extensive tuning when a cam is changed. I can tune a MAF car in half the time it takes me to do a SD car and that is on a dyno. GM has totally reverted to MAF Control sceanrios in all the late model cars and trucks. In trucks it has been MAF based control since 1996. In cars dependant of model its been MAF since the early 90's.

This is due to the fact of much stricter EPA specifications, the new ULEV emissions ratings and CAFE ratings. Not only is fuel controlled by air flow, timing is now also controlled based on air flow in the LS1 series controllers. If any of you have LS1 edit or have seen this you will see that timing is based on grams per second flow to each cylinder versus RPM (gms/cyl vs RPM).

 

Cool, I learned something today

Is this in any way the same has Variable timming on a Honday Vtech engine? or is this something totaly different.

 

I was wondering if the newer MAF sensors could be adapted to work on the earlier L98 engines they are much cheaper and look sturdier and have a bigger bore?

 

totally. v-tech is adjustable valve timing, via lifter pump up at high rpm.

 

Never heard of that without redoing the entire system and puttin an LS engine in.

 

Im running a 2005 Ford Mustang MAF sensor on my 89 383 Vette and having great results..Only thing I had to do was solder in the new plug and have my bin files changed over to handle the new MAF sensor. Here are some pics of the new sensor inside a Blowerworks tube..The Ford maf sensor isn't as fragile as the Corvette sensor was with there thin wire, this is a blade sensor and it could probably be dropped on the ground and kicked around without hurting it , plus there way cheaper then the GM Corvette sensors....WW

 

And what was done to the BIN files?

 

You would have to ask Mick Stevens that question, he's the one doing my tune, Mick took care of the files for me.Whatever he did it was a one time change, from then on it was perfect and didn't have to be changed again.....WW

 

I can make the tube myself being a machinist I need to know how to make the changes to the bin files or some one that can burn me a chip for a basicly stock 86e L98 This looks like a great alternative. Right now I am getting a 33 code but the thing still runs as strong as ever except the idle is a little rough.