Dyno run

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Cloggy Saint
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Post Wed Sep 27, 2017 5:22 pm

Decided to put my car on the rollers today more out of curiosity than anything. 159hp is more than I expected but less than I hoped for! On the plus side the torque value is somehow higher than factory spec. The tester said it's running lean up to the point where the graph dips and from there on it runs too rich. He also plugged into the diagnostic socket which returned fault codes 1, 29 and 50 but he wasn't really sure what this meant! I didn't think E30s returned any diagnostic info ...?
Can someone with knowledge of dyno charts read any more into this?


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Post Thu Sep 28, 2017 11:18 am

Is the dyno chart showing the actual measured power at the rollers, or a "calculated" engine output at the crank?

If the first, I'd be pretty happy with that considering the transmision losses you would normally expect.
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Post Thu Sep 28, 2017 12:11 pm

I'm not sure. Let's go for the first one.

edit: confirmed as power at the wheels.
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martauto
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Post Thu Sep 28, 2017 3:40 pm

How old is the engine ?

Mart.
Only the E46 cab left now.
Just got too old.
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Post Thu Sep 28, 2017 3:44 pm

It came from a 1990 auto and has covered 116k.
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martauto
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Post Thu Sep 28, 2017 3:50 pm

Well I would be really pleased with that .
That's a good amount of torque as well !!

Mart.
Only the E46 cab left now.
Just got too old.
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Post Thu Sep 28, 2017 3:53 pm

I'm not overly disappointed but it would have been nice to have one more hp, 160 sounds so much better than 159!
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Post Thu Sep 28, 2017 3:57 pm

Cloggy Saint wrote:I'm not sure. Let's go for the first one.

edit: confirmed as power at the wheels.
Yours is a standard M20 B25 right?

Assuming a 15% loss through the drive train (which seems to be a reasonable estimate for a RWD car), your engine seems to be putting out around 187 bhp....

Either an "optimistic" dyno, or an exceptionally well kept engine and transmission...

I would ask the dynoman if he has any charts for other M20 B25 cars to compare because the absolute values look a bit off to me.
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Post Thu Sep 28, 2017 4:04 pm

It's all standard apart from a Speedtouch chip. It may be an optimistic dyno but it's definitely a well cared for engine.
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Post Sat Sep 30, 2017 5:11 am

its not rwhp it is at the engine based on the numbers, looks ok except for 4500-5100
E30 325is with M20B31
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Post Sat Sep 30, 2017 10:41 am

Yep, it was measured at the flywheel, my bad.
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