Begining .. Converting 1984 Mustang SVO to MAF - Datalog

[DRHaulsee]

I just finished converting my 84 2.3 Turbo SVO from VAM to MAF. I've played with the transfer MAF transfer curve and have the engine cold starting, idling, and throttle blipping well. Unfortunately I can't get it out of the garge to drive due to all the snow we've had.

I'm a novice at this and I'd like you guys to look at the attached datalog and see if any red flags pop out as to things I should look at before I drive this thing on the street.

Here are the specs.....
2.3 4 cylinder Turbo, currently stock, 35 pph injectors and set to run 18 psi boost
55 mm SuperCoupe MAF, P series EEC with QH 1.6. LC1 wideband and BE 2010
I used the PE-MAF bin as the starting point for this conversion and edited the MAF transfer curve and injector size as required.

Yes, I know the 55 mm MAF is too small. My 80 mm MAF is in reserve for my 16V DOHC Folvo (Ford 2.3 block-Volvo head) turbo engine in the Capri II. I wanted to learn something about tuning before I moved to that project.

[decipha]

you'll be fine with the maf for now its good up to 250rwhp

the datalog isn't telling me much since there is really no load on the engine, won't really know until you actually drive her to see what shes doing

where did you get the transfer for the maf?

[DRHaulsee]

where did you get the transfer for the maf?

I got the transfer function from the GURE Strategy and the COS bin.

I've had to modify the low end of it to make the car start and idle correctly.

Well, I've been out shoveling snow and salting the driveway so I have some hope I can ge the car out of the driveway tomorrow.

[DRHaulsee]

See attached...

My comments.

It's rich under boost. That means I need to play with the MAF xfer function some more. The MAF reported a max air flow of about 575 kg/hr or 21 lb/min. That equates to about 210 hp @ almost 5000 rpm in 3rd gear if you were to believe it was actually flowing that much air. I don't beleive the car wasn't making that much power but it felt pretty good. It seemed significantly stronger than when I was running the VAM.

I think the MAF function is probably over reporting air flow by 5 to 10% at the high end. That's pretty obvious by the fact that it was running about an 11:1 AFR under boost. I'd like to get that to somewhere between 11.5 and 12.

Is that a safe number under boost?

The car ran beautifully on this outing. I didn't have any stalling issues or any real problems with bucking. I drove out about 3 miles from the house to deserted area and started the accel run and data log. After that I started a new log to record the drive back to the house.

On the return drive the AFR pretty much stayed in the 14's except when I came off the throttle in decel. It was also in closed loop on the drive back.

Comments?

[POPSRACING]

Give me a shout....

[decipha]

you don't adjust the maf to get your desired afr, you adjust the maf to get the commanded afr

adjust the fuel tables to demand the mix you want

You maybe adjusting the maf to compensate for the injector difference, the stock maf on the stock GURE ecu is pretty much dead on, in boost at high loads the GURE ecu's demand 10.98 and the afr is right there with it

[DRHaulsee]

You maybe adjusting the maf to compensate for the injector difference, the stock maf on the stock GURE ecu is pretty much dead on, in boost at high loads the GURE ecu's demand 10.98 and the afr is right there with it

The only adjustments to the MAF xfer right now are what I had to do to get a stable idle. I've had to add some additional points down low. Perhaps I'm mistaken on this. The problem I thought with the idle was that a 2.3 Turbo will only pull about 14 kg/hr at idle and I expect an SC pulls at least 25 from the larger displacement and the drag of the supercharger. The SC MAF xfer was basically undefined where the engine wanted to idle. I went from a rolling 1600/500rpm idle with intermittent stalling to a rock solid 950 rpm +/- 25 rpm when I added the points.

Attached is a screen shot showing the changes I made to the maf xfer.

On the datalog above I was concerned that the mid to low 11's were too rich even under boost. Evidently not. The car actually runs real well right now.

What kind of run and datalog should I make? The one above was a hard acceleration. Should I do one from say a 3rd gear roll with increasing throttle opening until I get to wot?

Thanks,

[teal95]

The limiting factor (especially with a turbo) is EGT. Once EGT gets in the 1600-1650 F range you are in danger of melting the exhaust valves and turbine wheel. When I worked at Chrysler we had the 2.4t running at 9:1 AFR at the high end to keep the EGT in the desired range.

steve

[fastsvo]

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