Another E30 GRM Challenger

[sandlock]

Keep up the good work.

[acolella76]

We used a rotary carbide burr bit (like pictured below) on a pneumatic die grinder to very carefully remove material from the combustion chamber focusing on the area with the deepest pit. When the pitting was no longer visible we blended the once the area into the rest of the ridge to mimic the original shape of the combustion chamber. Once that was done we hand sanded with progressively finer sand paper until it was sufficiently smooth.



There are a few spots that were too close to the valves to really do anything about (especially with the valves still installed) but the major pitting is all taken care of.

sweet, thanks for the info

[Jonny Cash]

Maybe I missed it. What kind of wheel/tire combo do you guys plan to run?

This event is alot of fun, youll love it.
Good luck getting the car together.

-jay

[Mgriz]

what did you do to smooth out the head? My head has the same thing on one of the cylinders...

We used a rotary carbide burr bit (like pictured below) on a pneumatic die grinder to very carefully remove material from the combustion chamber focusing on the area with the deepest pit. When the pitting was no longer visible we blended the once the area into the rest of the ridge to mimic the original shape of the combustion chamber. Once that was done we hand sanded with progressively finer sand paper until it was sufficiently smooth.



There are a few spots that were too close to the valves to really do anything about (especially with the valves still installed) but the major pitting is all taken care of.

[acolella76]

what did you do to smooth out the head? My head has the same thing on one of the cylinders...

[silence]

Brings back memories... Welcome to the GRM club, can't wait to meet you all, keep up the good work.

[Lof8]

I've been using an oem sachs e30 clutch on my S50 swap trouble free for 2 years now. I'd recommend sticking with what you've got there. As for the sloppy steering rack, replace it with an e36 rack - they're quicker.
good luck! I'll be there to check out the event again this year.

[Mgriz]

Time for another update after a busy weekend.

When I got home from work Friday I was greeted by this beauty... Picked it up used off a guy on cumminsforum.com, it's a stock HX35w from a Dodge Cummins diesel.



It's in pretty good shape, spins nice and has no shaft play. I took the compressor housing off to clean it up and have a look at the compressor wheel.







Here is a look at the hot side. Nothing much to see just a bunch of carbon soot... Something I didn't realize before, the internal wastegate only vents one turbine inlet. I'm wondering if this is going to be an issue if we go with a twinscroll manifold? I guess ideally we would have two external wastegates for this kind of a setup...



We then towed the car to a local car wash to blast some of the gunk out of the engine bay. It did a pretty good job, so its somewhat decent to work in there now. We also dragged along the transmission and diff but the pressure washer barely put a dent in the caked on grime on them...'





We had some scrap steel laying around and fabricated solid engine and trans mounts.



We took xwill112x's advice and smoothed out all the combustion chambers. We ground down the pits then blended the section into the rest of the chamber. I think it came out pretty good.



We also uncovered an issue with the steering rack as we worked at blocking the power steering ports on the rack. The rack moves about an inch as you cycle the wheel back and forth... that'll make for some sloppy steering. Not sure what the issue is but we'll definitely have to sort that out before getting her on the road.

A couple of us started attacking the chassis wiring harness. We really should have labeled more when we were tearing it down... it's looking like quite the nightmare. Fortunately not much of it has to actually work, but figuring out what we do and do not need so we can clean up the wiring would be nice.

Thats all for now. Next weekend I think we're going to throw the engine back in the car to mock up the turbo manifold, if we can scrounge up some scrap tubing. Our plan is to use the stock exhaust manifolds and fab up something like this... except with a divorced T3 flange.

[einstein57]

Flip the manifold and make a y adapter mate to a t3 flange. Simple, cheap, and easy.

[MR 325]

You can take a porting bit or scotch brite to the scoring on the head.

If I were you I'd run the almost new E30 clutch over the used E36 M3 clutch. My Sachs stock clutch has 10,000 miles and counting on a 10psi 2.7 M20.

[xwill112x]

find another head without so many issues....

Depends on how much you gonna give for it..but id see how well the the pits cleaned up first.. Then decide if buying another head is needed.

[Mgriz]

Do you think we can get away with just smoothing it out the burrs on those pits or do we need to fill the pits? If so, between that and the hosed cam bearing surfaces its probably going to be less work to just find another head without so many issues....

[xwill112x]

smooth that combustion chamber out or it will develope hot spots.

[Mgriz]

Time for another small update. We've mostly been cleaning up all parts we've collected so far. The ihead is not in as good shape as it appeared. We took the cam out and discovered major scoring on the bearing surfaces (which I don't have any pictures of), I think we're just going to go with it and see what happens. We also found some pitting (maybe detonation) in the cylinder dome which you can see in the pics below.









We also recently purchased a Megasquirt 2 and JimStim from diyautotune.com. So far I've only put together the JimStim and hope to get the MS2 built and tested this week.

Assembled JimStim


Lame time lapse of assembly...


Next on the list is finding a turbo, figuring out a turbo manifold, and o-ringing the block...

I'm also researching our options for a clutch. The clutch we have is an almost brand new stock replacement. I don't think it's going to have much of a chance holding with the power we are going to try and make. So far it looks like our best option is a used clutch from an e36 M3. Anyone have any other good ideas for a clutch?

Thanks for looking :)

oh yeah, we've got a build blog up and running now.... we'll be calling ourselves el diablo speedshop.

http://eldiablospeedshop.com/

[Mgriz]

Spent a few hours at the Pul-a-Part and came out with an LSD from an 87 325is. Should be a 3.73, not too bad for around $65!