Morley

Count me in on staying with MAF. If you are looking for test subjects, I'll do it. Mine is an old 870 system converted to 165, so that might give you another angle to explore.

Ed Maher

You forgot one thing there. To make MAF works takes time, effort and MONEY. Swapping to SD is cheaper than buying a translator. Or buying a new MAF (to say nothing of buying a translator AND MAF) . Or replacing a MAF if it goes bad.

More power to you if you want to work with what you have. Just seems like the $$$ issue was being completely ignored, and IMHO it seems like SD's low low cost makes it attractive to anyone.

305sbc

iTrader: (3)

I wouldn't take it personal Ed, I think he was just venting a little. The conflict between the two has been going on a long time and sometimes people have been nasty in their past arguments.

89gta383

iTrader: (5)

At this stage of the game, who gives a damn about cost?

I can't remember how much I've spent, but I know it's more than $10,000.

Like I said before, we will all benefit from the knowledge gained, that's the only thing that matters.

bigals87z28

i think its cool that you can use a new maf for older cars, but eds got a point on cheap... as a college student, and an engineer, i see both sides of the ball... that translator is a cool thing.. but i would rather switch to SD...

doc

Lets talk about flow and how much flow it takes to make a certain amount of HP.

A screenless '94 MAF can flow up to 719CFM which is 406gms/sec. And I believe that TPIS flowed a screenless, cooler fins removed '87 MAF also at 719CFM. I believe that these two MAFs have the same inside diameter, is that correct???

My '99 LS1 car (with a MAF) makes 400RWHP with a flow of 310gms/sec. From these figures, can I make the claim that a screenless '87MAF should be able to make up to 524RWHP????

Whats wrong with my logic????

I am thinking that our MAFs are not as much of a restriction as we think.

BTW: My '99 MAF car's MAF table goes from 1500Hz to 12000Hz, the flow values are 2.55gm/sec at 1500Hz and 459gm/sec at 11250Hz. The last several cells all have 459 in them.

ANOTHER idea: Why cant we put our 75mm MAF sensors (just the center electronics portion) into a larger 85 or 90mm tube AND re-calibrate the MAF table according to the BLMs that we can record?

badgta

iTrader: (4)

i had a old spare one for a 89 car...... it didn't work but i wanted to see if i could do that... but unfortunantly the elctronics housing is molded right to the main housing........ if my memory serves me correct.....

i think the main hurdle is getting over this 255gsec thing...

lets face it folks. were using 80's technology to get alot of hp, and unfortunantly were going to have problems like this one.......

Craig Moates

Bah, all is possible. This is just an exercise for me to see what can be done.

Does anyone have a spare 'stock' unmodified 86-89 MAF sensor I could borrow? If so, get /w/ me offline.

Vader

Craig, et al,

You're a better man than I am. I spent the better part of 1½ years with a couple of ECMs on the bench, with power supplies, dummy inputs, loads, meters, square wave generator, A/D coverters, etc. all connected and jumpered in. I still have all the junk in a box somewhere, and some of the leads still hanging from the probes of my bench scope.

The 255g/s limit is a restriction, not the physical size or flow capability of the sensor body itself. The same sampling tube can be placed in a 6" MAf body if you really wanted to, but the ECM can only interpret inputs up to a firmware limit of 255g/S. Rewriting all the MAF scalars and recalibrating the MAF analog input would be a solution, but probably not a "plug-and-play" one.

The path I took was to reclock the ECM processor to a higher rate, then adjust all the "per second" or "per minute" parameters to compensate. The theory was that the ECM could think that the time based parameters were still in effect, but the real time would be half what the ECM was operating at. An automatic 510g/S ECM? So I thought.

I started with a TBI speed density ECM since they are simpler, but just to check the clocking changes. The ECM clocking divider circuit and processor handled the rate with no problems, executing everything cleanly. Programming the time based rates was another item altogether. I got them close, but some of the injector tables got out of range, and the injectors didn't like the short duty-cycle (real time) at all, and it all went to the box when it came time for relocation. It's still in the box. I think the system has promise, but would require an ECM reconfiguration, not just an EPROM or MEMCAL plug-in. I'm not about to build my own ECM when there are aldready far better ones sitting in junk yards all over the country, and connected to the harnesses that will make them work.

I do have a spare Bosch analog MAF for your use, but it is out of calibration. If you want it, just get me a shipping address.

Your philosophy may be more promising. Alter the analog signal from the MAF, then compensate in programming and MELCAL firmware scaling. I think you'll run into fewer issues than I did, but expect the unexpected.

Good luck. I'm sticking with the LT1s and newer PCMs for recreation, and letting you guys do all the R&D. Too bad the Delco Electronics guys were so short-sighted. At least they learned their lesson, or were "retired".

fly89gta

iTrader: (1)

Vader, how about trying to modify the TTA/GN ecm? The actual translator itself doesn't get rid of the 255 g/s limitation, its in what's called an "Extender Chip" which is just your basic aftermarket chip with that great feature among others...

mastrdrver

Has any progress been made, or did I miss it?

B4Ctom1

what post?

SLP IROC-Z

iTrader: (1)

if i stay MAF i definitly need a better unit, had to descreen the stocker just to get the damned thing to run right, no tuning yet. screens removed i gain 2mph in the 1/8 and 3mph in the 1/4 hot lappin. fruity

ski_dwn_it

Some of you guys need to really wake up. You CAN MAKE over 500+ HP with the stock MAF gutted.

Why can't people see that? I mean you guys listen to a few people that "think" the MAF is a restriction, while other people are running the units and turning 10sec to mid 11 sec 1/4 mile times. Comeon! fellas....what is more convincing...talk or results?

I am going to go out right now and track down some website that show what times a MAF car can run. But first I want you all to see this what switching over to SD for this guy did, and I can't believe that people actually endorse doing this. Its freakin kills me. LOL. Pulled from a website that shows detailed instruction on how to go from MAF => SD.

The first test of the season was run at Cecil County Dragway on March 4, 2000. The 7 runs were recorded as:
1 (MAP) 13.098@105 (let car shift to OD)
2 (MAP) 13.095@105 (let car shift to OD)
3 (MAF) 12.941@105 (kept car in 3rd to 5600rpm)
4 (MAF) 13.071@103 (let car shift to OD)
5 (MAF) 12.927@106 (kept car in 3rd to 5800rpm)
6 (MAP) 13.063@105 (kept car in 3rd to 5800rpm)
7 (MAP) 13.050@105 (kept car in 3rd to 5600rpm)


*note: all the runs had 60' times between 1.812 and 1.860 and so I feel are warranted for comparison..

Now show me the gain please? Comeon' you have to be out of your mind to tell me that is worth the trouble and he actually ran in the 12s two out of 3 runs with MAF. and none with SD. LOL.

Here is one site. His name is Beach Bum: 383/SR/219 cam

http://temp.corvetteforum.net/c4/bea...nSet-ups.shtml

This stite outlines MANY Vettes that are in the low to mid 11s with just a ported MAF.

Here is another site...same combo as I am running....

http://hometown.aol.com/corkvette1/myhomepage/auto.html

Here is a recent video of my car.......
http://temp.corvetteforum.net/c4/ski...s/numidia1.wmv

Guys I realize that we are all trying to get the most out of our cars and spend tons of cash to do it, but please listen to reason. If your running 11sec + ETs then the MAF is the least of your worries.....put the time and effort into something else. I want to see each and everyone of you run as good as possible and speaking from experience and having been around tons of race/street cars I can tell you that MAF will support major power.

I think the reason people point the finger so quickly at it and want to remove it is its out in the open and easy to see. But think about your plenum, your runners/ and most of all your heads. Are they the REAL restriction? Most likely. That is what you need to look at when your trying to get a GOOD running setup.

I can bet you that not one of you unless you below that 11sec mark, you would benifit one bit from a bigger MAF. A gutted one will flow 750 CFM. A 406 with 100% efficiency and 70* air @6500 RPM only requires 763 CFM. I don't think any of our engines are pulling that kind of air or have that kind of efficiency numbers.

You have to be realistic with yourselves, and ask how can all these guys run that quick, with the MAF. Is it really the MAF slowing me down or the other components that I meantioned earlier. I suspect if your honest you would reply probably something else, since I am not running that quick or making that kind of power, and these guys apparently can and are doing it weekend after weekend.

And before someone goes off on a rant about resolution of the MAF, as yourself......there isn't a NA car here that pulls 255 g/sec that is not in Power Enrichment. Which mean the ECM doesn't give a crap about the MAF reading and just runs a given set of Fuel parameters.

And don't tell me that you drive around at 255+ g/sec on the street, and need that resolution. Sorry not going to buy it, because an air hungry engine like mine or any other 383+ engine can go from 0-80 MPH at 1/4 throttle <255 g/sec with ease, anything more than that and your blowing the tires off of it or in PE mode and you just don't realize it.

So in actuality you have just as much resolution as anyone with SD....and yeah you can go more than 1/4 throttle that was just for example purposes.

Again its your money and you can listen to the marketing hype or listen to real world experience that is proven weekend after weekend.

tpi_roc

getting off topic