Dyno runs today

[brodee]

finally got the car on the dyno. Max HP was 144.8, torque 140.4. I'll post the graphs later.

The car is running VERY lean, A/F ratio was about 4 points off. I need to crank up the fpr about 2 more psi and try again.

I'm a little disapointed, expected around 155 at the wheels but with it that lean who knows what it should run.

Couple of pics......

[Rob]

dont get caught up in the peak numbers, they are meaningless. look at the area under the curve for the performance of the engine, and the the air/fuel for tuning. sounds like you need some tuning, hopefully that will help

[Jonathan M3]

what mods do you have?

[brodee]

Dinan chip, 272 cam, intake, headers, custom 2.5" exhaust. 156k miles on the bottom end.

[Rob]

I think those numbers would be about right for a stock m20 on a dynojet. i *think*

[brodee]

I think stock should be around 134 at the wheels factoring an 18% loss.

[brodee]

Here's the chart.. Click it for a larger version.

[SpencerM3]

WOW, thats lean. Looks like 16:1 around 5500.

Any noticible detonation?

[brodee]

none that I've noticed. As soon as I get a guage on the regulator I'm going to pump it up a little at a time and see what happens.

[nando]

maybe some larger injectors would help out. do you have any vaccum leaks?

[brodee]

maybe some larger injectors would help out.

That's not a bad idea. What size are the stock m20 injectors?

[mspiegle]

14# IIRC

[brodee]

hmmm.. I might bump up to some 19.5# and see hos it handles that.

[SpencerM3]

Not sure if S50 injectors are compatible with M20 engines, but 95 M3's (maybe even 325's) have 17# injectors that can be found dirt cheap.

One step up from their are the 21.5# injectors in the 96-99 M3s.

[brodee]

Not sure if S50 injectors are compatible with M20 engines, but 95 M3's (maybe even 325's) have 17# injectors that can be found dirt cheap.

One step up from their are the 21.5# injectors in the 96-99 M3s.

I thought my '95 M3 had 21.5's in it, hmmm. I changed them out for 24# when I added the cams and hfm. Wish I had kept the old ones :(