MAF conversion

[svobrown]

On my data logger I have a map to show the boost and vac. When or if I get a stand along I will be using it instead of the air meter to drive the engine. A 3 bar map cost about $100 new so it is much cheaper than a new MAF meter.
My used 80mm cost $45 off ebay. It came from a 96 cobra

[Pat_in_L.A.]

For those who have the funds:

http://www.pectel.co.uk/

[SVOBart]

Originally posted by turbizzy

What ever happened to the SDS? No one likey no more? Whuts Jon Dell Blair run in his 9 sec SVO?

I guess im stil trynna lear the engine management aftermarket and whut not. But i thought you didn't need a air meter with some systems correct? Does it soley rely on MAP sensor readings?

SDS = $$$

Megasquirt, even if you bought every module they have preassembled is a heck of a lot cheaper. If you've got the patience to assemble the kits yourself, you can get everything you need for around $400.

Megasquirt uses a speed denisty system, so you eliminate any direct air metering. It just relies on a MAP, air temperature and throttle position to calculate fuel.

[SVOBart]

Originally posted by svobrown

My setup is a easy swap and with the right tools (time) can be tuned in a few runs. Waiting on Bart for that.

Just whenever you want to bring it by...or were you wanting to tune it on a dyno??

[svobrown]

Do the dyno! Much better than pushing it back to the house if we break something too.
When you get yours up and going we can do a base line on yours the same day.
First of Jan?
Z1 is about halfway and I can get them to go cheaper when I say 2 or 3 cars.

[SVOBart]

Sounds good. It should run by then (I hope!).

[turbizzy]

Im still not really sure what i want to do, MAF or most likely a stand alone. Megasquit looks good. I wonder what all i need for the Megasquirt. What about the XFI and Motec and Commander, dont those use a air meter? Do you guys think air meter is better or not? So many questions, i wish there was a basic write up on all stand alones and pros and cons plus features and such.

[caroth]

Originally posted by svobrown
Do the dyno! Much better than pushing it back to the house if we break something too.

I am going to have to disagree with you there. Buy a LM-1 with RPM cable and datalog/tune on the street. You will spend a few hours logging and tuning the MAF curve.

I have an 80mm running in the SVO with P series code. I have a 70mm in the Ranger with LA series code. I run the J3 Stokes adapter ($60) in both vehicle which means I need to reprogram a $2 chip everytime I make a change. The chips are re-usable and the programmer is $70.00.

The P series is much easier to tune, the LA requires tweaking a few other parameters. The SVO idles like our 200 Lincoln LS and makes as much power at 16psi as it did at 21psi with the VAM.

It is no longer considered MESS AIR. It is not for the computer challenged, it does take a little patience.

[SVOeric]

I suppose it depends on your plans--

If you have one setup, and you don't plan to change things, a trip to the dyno is cheaper than a LM1

and I looked at the megasquirt -- it's not for the light of heart, if you know what I mean.
I helped somewhat with a SDS setup, and it is MUCH simpler.

[svobrown]

I have the datalogger with maf volt, rpms , boost wideband, TPS, exhaust temp. Very good information.

Just alot better on the dyno than in the highway. No bumps, turns, quick stops, other drivers.

I just got to do it and stop talking about it..

[caroth]

There is some time associated with tuning the MAF. You set the base fuel to a static number (like 12.0:1 AFR) and force open loop idle and open loop driving, then you go data log. Remember with tuning a MAF, you are adjusting the MAF flow numbers at each voltage point.

So lets say at 2.3 volts on your MAF you get an average of 11.2:1 AFR. I have not found a formula that will change the AFR to exactly 12.0:1 in one shot. I have played with many formulas that will bounce you on either side of the 12.0:1 line until you finally get there, but that can be dangerous if your initial values are way off. My current formula will inch closer to 12.0 each time, I can usually have the MAF tuned in 3-4 datalogging sessions. I do them out of the city at night, where I can have long stretches or road without cars or people to worry about.

You can certainly use a dyno to tune the MAF, but how many dyno shops will allow you to sit down with your laptop, datalog, calculate your new MAF values, burn chips (or upload each time with EEC tuner), and try it again? For one, you cannot get enough data with a 4th gear roll on a dyno. Sure you can probably tune the high end of the MAF signal, but how many times are you WOT on the street? Dyno shops are good for tuning a spark curve, and screwing around with fuel pressure, that is about it.

Most people that have the MAF running correctly have invested the time to datalog on the street and tune the MAF correctly. These folks are concerned about drivability and performance at all throttle positions. My SVO and truck have greatly improved in both performance and fuel economy.

No offense Eric, but SDS is ok for drag racing, but for true street tuning and optimal fuel economy, you just can't beat a factory computer.

If anyone would like some additional information on the MAF, you can always feel free to email or PM me. There are many guys at turboford that know way more than I do.

[caroth]

I almost forgot...

Mr Fleming, have you abandoned the "hot wire" MAF on your SHO? What was wrong with it? What did you switch to?

[QWKSNKE]

Originally posted by caroth
There is some time associated with tuning the MAF. You set the base fuel to a static number (like 12.0:1 AFR) and force open loop idle and open loop driving, then you go data log. Remember with tuning a MAF, you are adjusting the MAF flow numbers at each voltage point.

So lets say at 2.3 volts on your MAF you get an average of 11.2:1 AFR. I have not found a formula that will change the AFR to exactly 12.0:1 in one shot. I have played with many formulas that will bounce you on either side of the 12.0:1 line until you finally get there, but that can be dangerous if your initial values are way off. My current formula will inch closer to 12.0 each time, I can usually have the MAF tuned in 3-4 datalogging sessions. I do them out of the city at night, where I can have long stretches or road without cars or people to worry about.

You can certainly use a dyno to tune the MAF, but how many dyno shops will allow you to sit down with your laptop, datalog, calculate your new MAF values, burn chips (or upload each time with EEC tuner), and try it again? For one, you cannot get enough data with a 4th gear roll on a dyno. Sure you can probably tune the high end of the MAF signal, but how many times are you WOT on the street? Dyno shops are good for tuning a spark curve, and screwing around with fuel pressure, that is about it.

Most people that have the MAF running correctly have invested the time to datalog on the street and tune the MAF correctly. These folks are concerned about drivability and performance at all throttle positions. My SVO and truck have greatly improved in both performance and fuel economy.

No offense Eric, but SDS is ok for drag racing, but for true street tuning and optimal fuel economy, you just can't beat a factory computer.

If anyone would like some additional information on the MAF, you can always feel free to email or PM me. There are many guys at turboford that know way more than I do.

I agree. When dialin in the MAF curve it is best if you have some street tuning done for the lower points. Then do the mid and upper points on a dyno. This is the way we have tuned my 93 cobra. Street tune for a week or so, then put it on the dyno. For what its worth, the dyno I use has no problems with me using my laptop hooked to the car. But I usually rent it by the hour as well.

Here is what worked in my application for dialing in the MAF on the dyno

Look at your A/F chart and write down the MAF voltage every 1000
rpms. Above that write the commanded A/F ratio. Divide the commanded
ratio by the actual ratio and adjust the MAF function at that voltage
point by the result. If we commanded 12:1 and got 10:1 we have to
adjust the transfer function by 12/10, or 12%. Smooth the points in
between the ones you calculate. It shouldn't take more than 3 or 4
pulls to get the transfer function dialed in.

[svobrown]

I see your point. Now I need to make the time and do it.
I have the moates J3 with just a couple of chips thats Wes made for me. Good for a start but lean on bottom then rich in mid then close again on top.
This was one of my first runs at 32 psi on fuel and 18 on boost.

[SVOeric]

No offense Eric, but SDS is ok for drag racing, but for true street tuning and optimal fuel economy, you just can't beat a factory computer.

If anyone would like some additional information on the MAF, you can always feel free to email or PM me. There are many guys at turboford that know way more than I do.

none taken Chris--

The dyno we used for the reunion this year, the guys are great, and if you talk to them, and are flexible, (ie can run when they aren't too busy) they will work with you however you need. When we were working to tune the SDS -- we ran several tests where he would put load on the dyno, and we would run through the gears.

I believe using the Ford computer is probably the easiest way start with economy and drivability, and tune in the performance, not to mention ease of setup. but I don't see a reason the SDS couldn't be programmed to do the same, only that it would take months of working on it every day to get it where it would be close to as streetable. I can see how doing a complete tune on the dyno would be dificult tho, as you said.

I was only making a comparison between the megasquirt manual, and the SDS manual -- the SDS seems to be much easier to setup.

After the 1C SVO I'm putting together is on the road, that is my next planned project -- I've been looking at different computer managment systems, and trying to form a stratgey on which way to go.

I'd be very interested to hear more about your setup, and how you went about getting started with it.