Camshaft Degreeing for performance

[Jean H.318TI]

i have an m42 boosted now

[juan.manjarres]

Come on people lets push to find these M44 cam adjustment specs.

[familytruckster]

I spent days searching....I bought back issues of grm that had the ti project car, poked at the guys that worked on it...nobody remembered the specs.

I don't have the time and money to spend on hours of dyno time yanking my motor apart repeatedly to adjust the cams...I'd consider donating some money for someone to do that though.

[spidertri]

I've found some threads where guys were discussing getting power out of the M44 for the SCCA ITA class a few years ago. They all talk about intakes and exhausts but not about the cams (which had to stay stock).

There doesn't seem to be a forum dedicated to the compact cup that I can find. Those guys have to have done some playing around with it.

John, do you remember any other details about that article you found? Was it from a non-US source, on a forum, on a blog, did it seem like an official bmw reference?

[familytruckster]

Yeah, the SCCA ITA class was what the GRM ti was run in. I'm sure someone adjusted the cams, the cams were stock, however there is adjustment in the factory gears... sooo.. One of those non discussed but everyone did grey mods.....And one nobody wants to discuss because of giving away a performance secret/advantage.

[juan.manjarres]

Been looking around all day today... No luck

[spidertri]

Originally Posted by familytruckster

I'm sure someone adjusted the cams, the cams were stock, however there is adjustment in the factory gears... sooo.. One of those non discussed but everyone did grey mods.....And one nobody wants to discuss because of giving away a performance secret/advantage.

Well, that's what I meant by the cams had to stay stock. If they could have gone aftermarket then it wouldn't apply to us with stock stuff.

[juan.manjarres]

We should revive this.

[juan.manjarres]

John would the cam gear adjustment be the same between an m44 and m42?

[fast_frizz]

I have an M42 318ti that I am trying to find some more horses in. Since I use this car primarily at track-events, the high-end power bump is tempting. The car usually spends most of its time between 3500 and 6500 rpm anyway.

Spiderti - can you provide links to the SCCA threads you mentioned?

[spidertri]

I don't have links (or remember) the threads I originally found but I just searched google for "scca ita bmw m44" and found a bunch.

Some of these threads contain ti hate, reader beware.

http://www.improvedtouring.com/forum...ad.php?t=18797
http://forums.bimmerforums.com/forum....php?t=1235912
http://forums.bimmerforums.com/forum...d.php?t=520534

[hornet53]

Originally Posted by xxxJohnBoyxxx

I read a article from a BMW tech and did it on a dyno and had the exact cam degree number from stock to make the most power. He gained like 13hp. It was something I read in maybe 2008 and I can't find the article now. It was very detailed with dyno graphs and exact cam deg during the dyno pulls.

If I could only find that we would be all set for N/A motors. I already have the degreeing for any supercharged or turbo car. It has almost no overlap so the boost doesn't blow out the exhaust valve. This will make a good difference on any boosted I-4 M44.

I have done some more cam timing work on these engines and you are not going to gain 13bhp by adjusting the cam timing, unless, the engine was not setup properly in the first place. Moving the cam timing will only move the power / torque curve up and down the RPM range. BMW would not waste 13bhp like that. If you have had a head skim or other work that moves the valve timing, then you must reset your cams.

There is no information on the Compact Cup forum about this as it is a new series and racers wouldn't give this information up to their competitors anyway.

[mulholland]

Originally Posted by hornet53

I have done some more cam timing work on these engines and you are not going to gain 13bhp by adjusting the cam timing, unless, the engine was not setup properly in the first place. Moving the cam timing will only move the power / torque curve up and down the RPM range. BMW would not waste 13bhp like that. If you have had a head skim or other work that moves the valve timing, then you must reset your cams.

There is no information on the Compact Cup forum about this as it is a new series and racers wouldn't give this information up to their competitors anyway.

Do you have any quantitative data/empirical evidence showing the gains/losses you experience? You stated previously you had done extensive testign and would post dyno's after you removed your personal information from them... those could prove helpful. I would even venture to say one could use a pretty simple engine simulaion program to run the gambit of intake/exhaust cam timing adjustments and find the highest peak yield...


As you stated (though it sounded like a basic understanding of the situation) the cam timing will move the torque curve.... when you move a torque curve up, you make more power. If you made 100tq at 4,000rpm vs 100tq at 8,000rpm, you would only be making half as much horsepower at 4000rpm. The idea being that in a tracked/performance driven car, you need the power down low much less, as with each sequential shift up, you never drop down to that portion of the rev range, making it dead space under your desired power band after getting the car going in 1st gear.

BMW would ABSOLUTELY "waste" 13hp like that for the sake of having a car with a rock steady idle, emissions, and desirable fuel consumption. On the contrary, a performance minded person with a one track mind would take 5mpg, dump plumes of soot, idle like a top fuel dragster, and sell his soul to get the edge and make the extra power where he needs it. If you think they didn't give up power and make compromises for a street car engine, any engine, you're kidding yourself.

[fast_frizz]

spiderti - thanks for posting. Especially the second one was interesting. I am considering a lighter exhaust, but it seems that most places I read about people trying different exhaust, it typically harms performance (lighter, though)

[derek502]

I have a quick question, I just removed the head on a M44 Z3 because the head gasket was blown. I removed the cam sprocket from the camshafts. I marked the cams/sprockets but how critical is it to have the cams perfect on the sprockets? I do not have the cam lock down tool.