ITBs, hot cam and long tubes on a b25: worth it?

[M-technik-3]

and it sucks

He asked, I gave him options

[thatphysicsguy]

Look at the setup that CA tuned used on that blue car.

I looked on their website and their build feature doesn't have any mention of them yet. But that blue car did give me the idea originally.

[AwakenNoMore]

I too am really interested in a cammed ITB M20. Just for the noise and looks alone. I have to wonder how feasible it is for a daily though.

[raudonis]

There is no "worth it" way to get around with, unless you have a pile of FREE junk parts lying around and all of your friends have fabrication skills.
Rebuild the motor, lighten up the original slug pistons, get lighter 135mm conrods from m52/m54/s52, get Schrick 272 cam with springs and HD rockers. Get long tube headers from ebay (IE knockoff) place your X-pipe where it should be. Make your own cold air intake. Get everything running with MAF and fully sequential injection and ignition. IMHO will have around 190HP and 250Nm at the crank.

[digger]

BFYB is never going to be great with the m20, atleast with the m20 there is generally enough information around so people know what works and what is BS

[Hooffenstein HD]

Rama (RHDEngineering/Race Head) is seeing a 30rwhp gain from his ITB's and ECU package on an otherwise stock M20B25. Throw in some high comp pistons and a large cam and you'd surely see some more.

http://www.racehead.com.au/?wpsc-product=m20-bmw-complete-itb-kit

http://www.racehead.com.au/?p=659

[Jasu]

Is it possible to make over 13.0:1 piston using std. bore, stroke and 885 head?

[nando]

You can keep the stock manifold and cam, use our PSIK, and gain 25 to 30 hp for $525. You get a massive improvement in engine response and performance with no hassle of having to use a standalone for an ITB setup. The induction sound too by the way is quite something.

The PSIK is by far the most bolt on power you can do to an M20B25.

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

I still don't get how a pipe and filter can make 30hp on a stock motor, given the limitations of the stock intake manifold and throttle.

also, MPH is a better indicator of power gains, and it didn't change much from the two runs - I see 0.5mph, not 4mph. the 1/4 time only tells you how good your launch and R/T were.

[SkiFree]

I still don't get how a pipe and filter can make 30hp on a stock motor, given the limitations of the stock intake manifold and throttle.

Pipe, filter, maf, and chip.

Look, I'm not going one way or the other. But unless someone does a dyno showing the opposite, you don't have much ground to stand on.

Is it possible to make over 13.0:1 piston using std. bore, stroke and 885 head?

It's possible, statically, but dynamically it's a different story. You'd likely end up losing power overall compared to a setup of 12:1 (at least that's what I see on M10 and M30 race engines).

[brody]

I still don't get how a pipe and filter can make 30hp on a stock motor, given the limitations of the stock intake manifold and throttle.

also, MPH is a better indicator of power gains, and it didn't change much from the two runs - I see 0.5mph, not 4mph. the 1/4 time only tells you how good your launch and R/T were.

There was much more than .5 MPH difference, can you not see the MPH curve? He had stayed in the gear too long on his "quickest" run. But because the graph doesn't show the 85.6mph run I am not mentioning the 3.3MPH increase. Again, this is was on an AUTO, Cabrio, hardly a prime performance platform but clearly a decent increase in performance.

Right from the customers "mouth"

Hi Brody

I took the car to the track before and after the PSIK install. Check out the graph. Impressive! A full second quarter mile reduction for a bolt on mod that makes the can run and start better is great. Feel free to post and reference where ever you would like.

My highest MPH was 85.6 at 16.64. I think I may have hit the rev limit (I set to 6900) too long on my quickest run, or the MPH may have been up there too.

Jim