Rating of Mods for performance

[ForcedFirebird]

as far as performance goes: best bang for the buck on these old cars would be to refresh the head/camshaft. Lots of M20s out there with worn rockers and cams.

This all day. If your rings are in good shape, a head rebuild on a high mileage m20 is worth 15-20whp alone (we have proven it on the dyno)

Electric fan conversion deletes about a 10hp loss.
In their test, the thermal clutch fan (cold, least amount of loss) ate 14hp at 5500RPM. The amount of fan loss is a function of air displaced (fan size and RPM) and efficiency of the fan, not the base engine's power. An electric fan, on the other hand, eats about 1hp through the alternator, and has the benefit of running based on cooling system temperature (set up right), not engine RPM. Granted the e30's fan is a little different, which is why I conservatively estimate 10hp instead of 15hp, but this also assumes the fan clutch is actually working properly - if it isn't, you're losing even more (along the lines of a hard mounted fan).

I have dyno tested an m20 clutch fan delete and it was .4whp - yes four tenths. On another note, the little horn in the factory air box lost 4whp when removed. Cone filter adapters for the AFM are a joke, stock box is superior to it.

Thoughts on this kit:

https://www.millerperformancecars.co...it-psik-detail

If your OEM electronics are in good shape, you certainly won't gain 25whp from that kit. They claim big numbers from their stuff, but DIYAutotune did a Megasqurt PNP conversion on an m20 and the AFM being replaced with a smooth pipe was only 3whp. They also compared the tired m20 with the stand alone - they got ~15whp peak and 23whp under the curve - BUT - you are comparing a stock mapped ECU to a custom tune (we see ~8-10whp with a dyno-tuned custom chip)....

https://www.diyautotune.com/support/tech/hardware/diypnp/documentation/application-docs/1987-1992-bmw-325/

[jeffnhiscars]

The air horn delete LOST 4hp ?

[Kershaw]

It's a velocity stack, pretty important part of an intake.

[digger]

I have dyno tested an m20 clutch fan delete and it was .4whp - yes four tenths.

are you sure the clutch was good and actually locked up ? that is not very much.

i'm going to do the test next time i am at the dyno when the weather is hot again

[mjposner]

So my car is a low mileage (30k) former garage queen (on the test drive the seller actually told me to slow down), so no head rebuild and no chip.

ForcedFirebird, where are you in Florida??

[jeffnhiscars]

It's a velocity stack, pretty important part of an intake.

Just making sure I read it right before I put mine FS :)

[Kershaw]

ForcedFirebird, where are you in Florida??

You'd think somewhere on his shop's website or their facebook would be the shop address, haha.

[mjposner]

You'd think somewhere on his shop's website or their facebook would be the shop address, haha.

Online only??

[ForcedFirebird]

are you sure the clutch was good and actually locked up ? that is not very much.

i'm going to do the test next time i am at the dyno when the weather is hot again

Yes, good fan. The power steering pump was worth about 4whp.

The air horn delete LOST 4hp ?

Correct.

So my car is a low mileage (30k) former garage queen (on the test drive the seller actually told me to slow down), so no head rebuild and no chip.

ForcedFirebird, where are you in Florida??

Pompano Beach, right on the Fort Lauderdale line just off I95.

You'd think somewhere on his shop's website or their facebook would be the shop address, haha.

Don't think WOT-Tech.com has it - but a Google search will show the FL location. The store is actually a separate entity (my partner) online store from Indiana. The brick and mortar shop caters to more BMW's, online towards our GM market.

Online only??

No, come by and visit sometime. Small operation, so best to call first in case we are out at the machine shop/track etc. Office phone is 954-786-3100.

[Bmw679]

Electric fan
Suspension overhaul (reinforcement and poly bushings).
Cam
Miller War Chip
Injectors
Tune
Grippy tires.

Big difference!!