anyone turbo'd an m20b20

[Toby_Unna]

jar-la, very interesting upgrade dude! Is that on an older L-Jetronic 320i, and did you need new engine management?


Cheers!

read page one of the thread mate

[Speedtouch]

Thanks, but is it still running with the original L-Jet ECU?

[jar-la]

Hi!
It was a very low budget prject, and yes, it's running with the original L-Jet, but with mods, ofcourse
Firstly ran 0.5 bar boost for about 3 months, but due to it's high compr. ratio (9.8:1), the headgasket gone.

[img][img]http://img405.imageshack.us/img405/825/ ... qd1.th.jpg[/img][/img]
I had a reserve engine, take out the pistons, -2 mm from top machined down, and put back these (ca. 8:1)
[img][img]http://img211.imageshack.us/img211/1834 ... xn9.th.jpg[/img][/img]
I made two green subinjectors in the intake pipe,(the blue one don't work yet)
[img][img]http://img233.imageshack.us/img233/4353 ... tu9.th.jpg[/img][/img]
and an oil pressure switch command them:
[img][img]http://img53.imageshack.us/img53/5112/oga45bw0.th.jpg[/img][/img]
At this moment I fight with overheating problem(all this week, afternoon the temperature is 37 to 41 degree celsius).
What do you think guys, if I make a smaller diameter waterpump pulley(15-25%), to force it to turn faster, would be better?
To 320iSE
I have only homemade measurements with two person:
0-60M= 7.0 sec (factory=10 sec)
0-100M=17.9 sec (factory=31.6 sec)
with 4 person in "TEST" mode, fuel economy was 8.6 MPG, but at the end everybody smiled .
I think, it's not bad from an old 2.0 litre and 7 psi.(with original diff ratio 3.45)
And last, I know, a fully programmable engine management is the best way,and I will go for it later too...,becouse this is a necessity only.


jar-la

[Speedtouch]

Very impressive performance difference jar-la! Almost makes me want to buy my old '87 320iSE L-Jetronic back to try a similar project on...

That's a surprisingly high diff ratio for a 320i. Both my 320i and 325i were 3.64:1 IIRC. Perhaps you should look for a 3.9:1 LSD to really bring it to life!

Cheers,

[seba]

Any pics?
Mark

Well,I done some pics, but almost all of changes is home made by me, it's not a "showcar" engine bay, so you really wanna see?

Seba

The 3K k27 is too big for m20b20 street (no race), it's good for m20b25 and b27. You get boost on 25i around 3500 rpm (and is good up to the ceeling, I seew it, one of my friends took me for a ride-325i, K27,)-> on 20i is equal with about 4500 rpm. This K27 was on bmw 745i engines, they had 3,2 and 3,5 litre engines. I have a K28 in garage, it's a littlebit larger, then the K27, will put up later, when upgrade my b20 to b25 or b27

sorry, for the late reply. but thank you for the help. i was interested partly due to the act that i could have picked one up really cheap, anyway.

your project looks really ineteresting. i also like to do as much of the work myself.

good luck with the project, i would love to see the end result

[antony]

hey.

thanks for sharing that. looks like some impressive work.

i was almost convinced not to do it, and do an engine swap (which i'll eventually do anyways), but your project has got me thinking again. theres just not that many turbo m20b20 (even if there is a reason for it lol)


looks sweet as man

[Speedtouch]

What's the torque like off-boost with a CR of just 8.0:1 on a 320i? (Bearing in mind that this engine isn't reknowned for low-down torque in standard form.)

[Gunni]

probably just as crappy.

[jar-la]

Off boost torque is not bad, 'couse the turbo is spinning, when is no boost, and pull into engine some air. I know, the gauge is under 0, but still helps the engine breathing. After i start the car, is 800 rpm, the boost gauge shows -0.7 bar. When drive 1000 to 2500 rpm, it goes up from -0.7 to 0 and after 2500 rpm +1, +2,... In N/A form i see only -0.7 and at full trottle about -0.5. Any pressure above this -0.5 is help to the engine to turn faster. I think, this is why not much the difference.

And Gunni's right, was a few days, i drove with turbo charge pipes dissconnected, and then was very bad, no power, it seems like only four cylinder works of the six...

This week trying turn up the boost a little

[seba]

just took a look at your pictures!!! i dont even want to know how much work goes into changing the spark plugs!!!! lol!!

[jar-la]

Not that much, it just looks bad:
Half an our
Ten minutes to take down the aircleaner, charge pipes, turbo; ten for spark plugs change, and ten to put back them
( i have two stage colder RC7YCC plugs, and with smaller heads - as i remember, 16mm key needed - for easyer change)