cams...

[UDM Motorsport]

hi gruppe,
so how hard or involved is it to install cams?
i have a 87 325is.
I've heard a bunch about the 272 and 288 cams.
are those the 2 best choices? can i go more aggressive?
this is a street car...and occasional track car...but i'm always on the crazy side so i dont mind the lopey idling of the cams.
Do i need to change anything else with the cams?
thanks
franklin

[Jordan]

You dont have cams.

288 on a 2.5 m20 is a lumpy waste. Too much cam for a street driven 2.5

[e36sport]

What is stock duration?

[nando]

man, every time I see a thread about somebody wanting to dump a ton of money into an M20, I just want to cringe. if your motor is stock, you won't gain much from a cam. and if your motor is not stock, you just blew $4k to get ~195rwhp, with a timing belt and 12 valve head. save your money for a motor swap! if you don't have one already, get a Jim Conforti chip, it's the only bolt-on mod worth anything for the M20.

the only exception to this is an M20 turbo, but those still require a lot of money to properly setup and tune.

[MR 325]

Anyone who spends 4k on a stroker motor did something wrong.

I am spending under a grand on an e/i stroker and I should have I am guessing like 180 horse. We'll see.

Will be running the 288 cam.

[modifiede30]

get a Jim Conforti chip, it's the only bolt-on mod worth anything for the M20

I don't agree...headers are also a good modification and can be found relatively cheap. An engine swap can be much more expensive than a properly built M20. Most of the cost of building a strong and reliable engine goes into machine work. If you do equal machining to an M20 and any other swap, the costs of a non-M20 begins to escalate rapidly - harnesses, ecu's, sensors, exhaust modifications, many things would be necessary that aren't if you stay with the M20. I can see where a cam wouldn't do a lot for a stock m20 (although it will do a little), but if you build an m20 from the ground up, and do it right, the engine will be much less expensive than anything else, and likely just as reliable. And if you're going to build an M20 to spec, you might as well go the stroker route using Super eta pistons and a little extra machining. This will take full advantage of the cam. As for cams, if its a street driven car, go with no more than a 274, but please do something to the head or it will be wasted.

[nando]

but you're still doing all that work to gain maybe 30hp. it's just not a wise investment. a "cheap" stroker isn't going to put down 200rwhp, either..

look at how much dave spent on his stroker, or how about e30gumball from the uk? balls out and they still make less power than a stock S50.

[modifiede30]

Guess I'm more interested in the ability to build a cheap, better engine than a stock M20, for significantly less than dropping in something else. I did my stroker for under $1200, installed, completely rebuilt from the ground up, with all machine work and balancing, head work and cam. And I bet I'm pretty damn close to 190 rwhp, if not more, with a much better torque curve than a stock M20. I guess its all in what you're looking for. I have to keep mine within a certain BMW class, and this let me do that.

[UDM Motorsport]

i'm not looking for huge HP...but just something a little more.
I have a chip on the way now, exhaust/header soon and also MAF.
So next thing on the list will be cam. Just want to liven up the car a little more...that's all.
dont think i'll do a conversion on this car, as i'm doing it on my other car now.
thanks
franklin

[Skafrog]

I am waiting for rs4pro3 to finish his 6 throttle body intake manifold for the m20, imagine that thing with a cam, head work, and a MAF conversion.

[RedBaron86325]

Neither cam will net you too much power, but either will help a little. By installing a MAF and opening up the exhaust, a hotter cam is simply "logical". It sounds like you are on the right track. There is nothing wrong with keeping your M20 as it is a simple, reliable, and easy to maintain engine.

[nando]

And I bet I'm pretty damn close to 190 rwhp, if not more, with a much better torque curve than a stock M20.

I bet that you aren't. dave's 3.0l stroker put down 181rwhp, and that engine had a lot of work done to it.

[aaron_silva]

And I bet I'm pretty damn close to 190 rwhp, if not more, with a much better torque curve than a stock M20.

I bet that you aren't. dave's 3.0l stroker put down 181rwhp, and that engine had a lot of work done to it.

He didnt have a chance to tune much and he was going to go with a different engine management. There were still a lot of ponies trapped in that engine.

Aaron

[rwh11385]

And I bet I'm pretty damn close to 190 rwhp, if not more, with a much better torque curve than a stock M20.

I bet that you aren't. dave's 3.0l stroker put down 181rwhp, and that engine had a lot of work done to it.

He didnt have a chance to tune much and he was going to go with a different engine management. There were still a lot of ponies trapped in that engine.

Aaron

http://www.r3vlimited.com/phpBB2/viewtopic.php?t=7843

Proper Tuning

I'm not going to waste a lot of my $ on the M20, but let people do what they want Nando. And don't just repeat what others say about not making the stock HP of a S50. Franklin already is puting one into an E30, and maybe just is looking to make his 325 faster. I think for a street car for more liveliness, he should get a 282/272 dual pattern whatever. Also, get that MAF, some proper tuning, headers, and exhaust.....and that should be a really enjoyable ride.

I agree with the turbo it or swap it thought, but not everyone has to. People can love their simple 12V heads and the "classic" look or whatnot.....whatever reason they want to keep the M20 is good enough for them.

p.s. I think the M30AFM / 19# injectors will turn out as a good "bolt-on" upgrade for the M20. I'm planning on installing the M30 AFM this weekend, and dynoeing it next weekend. Hopefully, it all goes well.

back on topic: dual pattern.

[rs4pro3]

I need a M20 head castring before I can finish building it ;) ;) I sold off the three spair m20 heads I had laying around so I don't have anything to mount the throttle to so I can line everything up before I start cutting a flange for the Plenum. So If any body wants to donate a m20 head casting to me fell free to do so eta, I, holes dosn't matter.