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FrankenCoupe

After a catastrophic engine failure on track, I decided to take advantage of the situation and build what I have been dreaming of for 5 years.  The BMW motors are very capable but I am from a time when asphalt ripping torque was king.  Both the S54 and S52 engine coupes I've run are a blast, but holding my foot to the floor 70% of the time and driving like I am in a momentum car has left me wanting more.  I've thought about a small block Chevy engined coupe since 2003.  A fellow by the name of Hanson proved the concept in a Z3 a couple years ago.  His Z3 roadster is powered with a LS1 and is driven on the street.  My project in some ways will be easier since street manners and systems integration is a nonissue.  In fact I removed the remaining wiring harness last week. 

Yes there are still many take off parts in the garage.  You can see what's available here. http://www.pbfut.com/GarageSale/listings.htm  Many of you have purchased and helped the cause.  I am truly grateful.

Basic setup will be an LS2 motor from a 2005 GTO.  I am hoping to mate a Richmond Gear 6 speed transmission I've had since new.  I purchased the tranny 12 years ago for a 72 big block Corvette project I eventually sold prior to completion.

I am not sure how much I will document.  It is so hard to find time to post entries to a site like this.  But for now, here goes.

I found this engine posted for sale on a LS engine web site.  It was in Florida.  I am in California.  I posted a request on Bimmerforums Z3 site requesting assistance with checking the engine out.  45 minutes later, I had the arrangements made.  Got to love the power of the Z3 brotherhood and the internet.  The deal nearly went south a couple times but finally I was in possession 12-4-08. 

My dog Coda is always close by and keeps me calm when the frustration level begins to rise. 
Projects like this have many opportunities to loose it
.

Engine bay mostly cleared for the new bullet.  Notice no brake MC, booster, or ABS pump

New brake, and clutch master cylinders and pedals
The angle make it look like they are low but are in fairly
good position.  Need to raise them about an inch. 
Within adjustment limits I think.

A few more shots of the LS2 on the stand as it was shipped to me.

Inevitably, the question comes up regarding the rear pan seams.  I never had problems with the S54 and that thing saw a lot of track.  I really think the early install at about 10K miles made the difference.  This car had some issues at some point in time.  It was hit at both ends some time in it's life.  Though straight, seams throughout the car have popped.  I addressed the rear pan during the initial build.  I added a triangle into the rear support.  It ties to a plate that attaches directly to the differential.  No more movement at all.

I took part in a group buy on a new radiator.  Size is questionable for the LS motor.  The thing is, thicker radiators are not always more efficient.  I'm a bit skeptical, only time will tell.

5-25-09  OK it's been way too long since I updated.  I have not spent very much time on the car at all.  Work and a buying a little project house for mom set me back big time.  I was able to put an hour in here and there fabbing parts of the motor, tranny and shifter mounts.  Doing so made the jobs not feel difficult or frustrating.  I think my biggest frustration was getting the holes in the plat that mounts to the block in the correct location.  It took me a few tries before I was satisfied.  I am pleased with the results.

My first step was to see if I could effectively re-route the steering column so as to make room for off the shelf headers.  Customs are nearly $1000 in the area and frankly, I just wanted to see if I could do the entire job myself even if it meant giving up a bit hear and there. 

Funny how you look past the dirt until you take pictures.  I power washed the hell out of this car after the S52 blew up.  Amazing how that oil just keeps finding it's way back out of cracks.

Off the shelf block huggers slide right in.

Motor mounts were surprisingly easy to put make.  Since using solid mounts is not an issue and preferred for tack it also made the job more simple.  No comments about the welds.  I know they are not the prettiest.  The small piece bolts to the front subframe.  Leaving it loose makes aligning the bolt holes on the end of the mount to the connector very easy.  I can place the engine in the car in under five minutes.  With tranny attached.

The transmission was pretty tight.  I originally had the motor and tranny lower but it place the pan too close to the ground.  Raising put the tranny up in the tunnel higher.  The tunnel pinches down some up high and it caused the linkage to just touch.  A 5lb sledge and a few whacks fix that problem.  The shifter location of the Mcoupe is 7 inches aft of the location I had a mount for...  Some scrap plate and angle made easy solution to the problem.  I used the angle to stiffen the plate so the shifter is rock solid.  For those wondering, that is not a t56.  It is a Richmond Gear 6speed.  I bought it new 14 years ago for a project that sold before completion.  In a way, it is easier since locating the shifter was nothing more than lengthening the shift rods and modifying the shifter mount.

Fits like a glove.

May 2010

The Big Push to finish

OK it's been 2 years.  Time to quit dicking around and finish.

I did not like the LS1 Camaro pan.  It was too low and I would have tore it off the first off.  Saved up 500 big ones and had a custom pan built.  Looks like nice work.  The baffles are interesting.  Hope they work.

Ok baby, ready for your new heart?

I fabricated a better keeper for the throwout bearing. 
The extended stud that came with the bearing did not position correctly and just did not feel right
The shims that came with the kit were needed and set the bearing perfect.  Zero slop but the
bearing pulls off the pressure plate fingers just enough so it's fully released and not spinning.
The Howe bearing works perfect with a 7/8" master.  Very short throw.  May be a bit heavy
for the street.  You may be able to get away with a 5/8" for a lighter feel.

Open Wide.  It is much easier to put the motor and tranny together out of the car
Then shove the whole assembly in place.

Yes it's all done on jack stands.

Some minor sheet metal work to complete but it's functional for now.

Fuel regulator and oil filter.  Glad the brake system is now inside the car.

Lots o room in front. Hoses were a bit of a piece job.

Oil cooler is up out of harms way and worked well on the S52. 
Hopefully it will be able to keep up with the bigger motor.
That's a new Z3 Aero bumper.  My old one was just too buggered up.

It went in nice and easy.  I wet cranked the motor over to pressurize the oil and fuel system. 
Minor fuel leak requiring a washer.  I made one out of of a silicone spark plug boot.  I just sliced it and made a thin washer.
Then, a major oil leak.  One of the bungs on the custom oil pan had a pin hole flaw in the weld.   No way to fix in car.
It all had to come back out. 

5-14 Got it all back together.  Wet crank, no leaks.  Cool ready to rumble.  Powered up the ECU and no fire.  SHIT!  
One full week of an hour here an hour there.  She fired 5-22.  Exactly 2 years to the day and hour of the exposion.
I realized it later that day the timing was unintentional and a little spooky.  I figured out, the aftermarket shop that did the
stand alone harness had inadvertently flipped the crank sensor leads when they repaired the broken connector. 
So the 12v pos and neg were swapped.   Easy fix.  Just hell to find.  I kept looking for mistakes I could have made.  
So, I am 3 weeks dicking with 2 errors made by someone else I paid to do the work.  

5-26   Ran it on a Dyno today.  It's a bit lean.  402/376 at the wheels.  Needs a tune and race gas.
One of the shop helpers videoed the pull.  He said he would utube it but I have know idea when, or how to find it.

I did a video using my camera but the sound overpowered the system and it was just a garbled mess. 

Maybe someone will have a camera at the track this weekend.