Best Prof Chip for the M20B25

[E30Nova]

I have a hard time believing that dyno chart. But then, look at all the stuff done to the engine. And for the Mark D chip, it says "cooling fan present" whereas every other run had no cooling fan.

See, my thing is I could not care less about comparisons, I know what an M20 does. I figure a 6 pot 2.7 SOHC with reasonable tuning should make 180RWHP, why the hell not an M20?

I don't see why even with the shitty intake these motors should make acceptable power, cheap. $1000 should cover it, or close to it.

That AND driveability too...nice fat torque curve. MPG is likely to be shit, but no car payments, right? Old school glory, right? WTF.

Supposedly the head is the real problem, so unless someone comes out with a new head design that's cheap as hell, I don't see N/A M20 builds getting good power for a grand.

Matt

[Sagaris]

I have extensively modified a car or two in my time and in the end it was a waste of money, I didnt make near the amount of power I wanted to, and diagnosing drivability issues was incredibly difficult. I have since learned to make only the most basic, cheapest, and easily reversible modifications (my e30 has injectors and a chip and that is it, no more engine mods) . The money I DONT spend on a cam, headwork, headers, MAF conversion, and the like goes into all new suspension, tires, brakes, and into my pocket.
Just my philosophy on cars and upgrades.

[CoClimber]

I also have a MarkD chip with stock injectors. I was going to do back to back timed runs to measure performance increase but ran out of time. The car needed to be ready for the autocross season. Seat of the pants says that there is little difference between chips. Problem is, a 10% increase will be hard to detect. On the other hand, the timing lights can detect it.

My feeling is that if you aren't racing, it's not worth it. If you are racing, work on suspension and tires first.

[jlevie]

If the engine is in good condition and the engine management is operating as it is supposed to, there's very little to be gained from a chip. A BMW engine is just that well tuned, "out of the box". The significant improvements in performance come from increasing the stroke, increasing compression ratio, increasing mass flow through the engine and reducing parasitic losses. Without radical surgery, there's not a lot that can be gained from head (see the Metric Mechanic site for what can be accomplished).

[lennon]

A good chip makes a noticeable difference on m20b27 engines, that's for sure. I tried a few and liked Mark D's the best. I also noticed the Mark D chip I had in my b25 car, but not nearly as much as in an eta. I probably wouldn't bother with a chip on a b25 again. If you build up the motor with high-comp pistons, a hot cam, yada yada, it's time for some standalone EFI like megasquirt, or I guess the WAR chip... I don't know much about that though.

[TrentW]

If the engine is in good condition and the engine management is operating as it is supposed to, there's very little to be gained from a chip. A BMW engine is just that well tuned, "out of the box". The significant improvements in performance come from increasing the stroke, increasing compression ratio, increasing mass flow through the engine and reducing parasitic losses. Without radical surgery, there's not a lot that can be gained from head (see the Metric Mechanic site for what can be accomplished).

Your responses are always concise, accurate and to the point Jim. I for one am appreciative.

[E30Gus]

Thanks guys! I'm doing an e to i swap and was wondering if I should get a chip and what kind. Definately a must with an eta engine! Now I think i will save my money and spend it on a set of air horns!

[Mystikal]

Your responses are always concise, accurate and to the point Jim. I for one am appreciative.

Accurate is up for debate.

The largest gains from M20 tuning stems from the fact that the car was factory-designed to run on 87 octane. Just by advancing timing for 91-94 you gain substantial power.