SNAFU; high performance 318is build that lives up to the name, Turbo M42 ➞ Turbo M20

[varg]

I pulled the M42 tonight.




I also did some prep work on the M20; rear main seal, oil pan gasket, valve cover gasket, fuel injectors, rocker shaft seals, hoses, misc gaskets. It's pretty much ready to go in now. I also found this. Someone used stop leak. I hate stop leak.

[Northern]

<stopleak pic>

Gross. Can that be flushed out of the rest of the engine? I can imagine if that is blocked, so is a lot of other stuff.

[efficient]

Dang talk about clogged artery. I'm going to be jealous if you turbo the m20 right away. My turbo setup has been sitting for a few years now

[varg]

Gross. Can that be flushed out of the rest of the engine? I can imagine if that is blocked, so is a lot of other stuff.

I inspected the inside of the head and block as well as I could without removing the head, it all looked clean. The water pump and some of the hoses were new, the fitting pictured was corroded. I flushed the block out and not much crud came out with the water. The engine seems to be as described.

Dang talk about clogged artery. I'm going to be jealous if you turbo the m20 right away. My turbo setup has been sitting for a few years now

There's no way I'd go from 18psi of boost to NA M20. It's going in with the 50 trim T3T4 I've been using on the M42 already attached, just with a .63AR turbine housing instead of the .48AR one.

[cleanasse30]

Nice progress! Do you plan to stick with the 50 trim long term once the m20 is in?

[econti]

Keen to see what the actual issue is with the old engine

[MF DOOM]

There's no way I'd go from 18psi of boost to NA M20.

[varg]

A week ago the engine went in.



Since then I've been otherwise occupied with school but working steadily in the time I could find. I had to make a "custom" wastegate actuator arm because my wastegate actuator would not fit between the turbo and the fender well.



The clearance between the silicone coupler on my compressor outlet and the header is scarily small. I'm going to have to make a little sheet metal shield to keep the huge amount of radiant heat from the header off of it.



This is how it sits as of tonight.



All that's left now is to build the megasquirt adapter, expansion tank mount, heat shield, and some small odds and ends like filling the cooling system. It should be running this weekend and I'm stoked!

[varg]

I'm on the road again, tuning and enjoying the noticeable improvement in smoothness and sound of the M20.





It's really slow for now, but as I tune I will progressively turn up the boost. I will quickly make more power than I did with the M42, I'm guessing it will be faster at 13psi than the M42 was at 18psi based on a previous race against an M20 turbo car which I barely beat. All tuning will be conservative since I'm still using the stock head gasket, which I won't likely push past 15psi. Some day I'll O-ring it and put the big turbo on :up:

[2mAn]

boost is addictive... I have to stay away from it.

[Dj Buttchug]

sick oil cap ornament

[efficient]

Dang dude
I'm jealous that your already boosted. I been sitting on my turbo parts for a long time already. How did you learn how to use megasquirt?

[varg]

I first was exposed to megasquirt around a decade ago, I'm pretty much self taught and have tuned many cars and built many units over the years. The tuning is the fun part, though I run into frustrating snags once in a while.

(edit)

[CorvallisBMW]

sick oil cap ornament

I noticed that too, I actually really dig it!

[Northern]

I have two busted HX40 compressor wheels that I think I have plans for now...

Can you clock your compressor housing to move the outlet?
Or what I'm really asking, is can you move the wg actuator around the turbo?