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OK, I bought the '84 first, in the summer of '96. Then decided I wanted another 928, with more "oompf", a 5 speed, even better handling and greater stopping power. As I was searching around, I came across a company that offered a kit to allow one to drop a Chevy small block into a 928. Now, there's some easy horsepower that's even easier to work on! So, I started looking for a "donor" car; a 5 speed that needed a new motor. In the summer of '97, I found a clapped-out 1979 sitting on a local Porsche dealer's lot. I picked it up for $2K and had it flat-bedded home, where I immediately began disassembling. I yanked the original engine, dropped it in the back yard, pulled the interior out and started taking a drill powered wire wheel to the chassis/carcass.

I then started searching for an engine. I responded to an ad in the local paper that was listing various engines for sale. I met with the seller and it turned out that he was running a custom engine "shop" from his garage. So, we talked about motors for a bit and I employed him to build a stout motor for my project. He had a psuedo-partner that was an Austin cop, so, like a dumbass, I trusted this guy. I ordered a 383 and 2 months later was delivered a 400! At the time, I'd been out of this motor-head game for so long that I didn't even know I was being handed something that I didn't order. There are several ways to tell the difference between a 400 and a 350 Chevy block, but you have to know a couple of minor things. I didn't know these things until it was too late. "Too late" in that this scammer had changed his day job and moved to a new address by the time I figured things out. But...BUT...so what? As it turns out, the motor that he did sell me has quite a bit more torque than the motor that I ordered and paid for. The drawback is that the Chevy 400 tends to eat oil. This is due to the shorter connecting rods (needed to keep the piston from smacking the cylinder heads because of the longer stroke of the crank) pushing harder on the sidewalls of the cylinders near the bottom of the rotation.

Yeah, it's an iron 400 block from the mid '70's with aluminum Trick Flow Twisted Wedge heads. The motor has a BIG cam (as far as streetable, flat tappet, hydraulic cams go), 5.58 rods with flat top pistons (around 10.2:1 compression ratio), and is topped off with a Lingenfelter/Accel SuperRam fuel injection system. (It started off with a 750 vacuum secondary Holley carb on top of a Weiand X-celerator low rise manifold.) I made custom headers for it (well, where else was I going to get headers for this combo? ;-) and I'm running a dual 2.25 exhaust system w/ 4 very free flowing Bullet mufflers. The engine develops 500 foot pounds of torque! Horsepower is around 430.

The motor is soooo small, compared to the 928 powerplant, and that's mostly due to the 928 engine being so wiiiide because of its dual over-head cam set-up. I can literally extract and install my headers from above, thru the hood opening! You can see the ground in many places under the engine bay. The engine weighed 460 lbs with the carb. The new injection system probably added 50 lbs. But you know what? The stock 928 motor is 610 lbs! Hard to believe, but true nonetheless. So, I've dropped 100 lbs off of the front of the car.

As the motor was being built, I upgraded the brakes to '89 S4 brakes and the suspension to '90 GT coilovers. The rear hub wheel carriers are designed for an ABS system. This prevented me from being able to reuse the original halfshafts, so I upgraded those to S4 design as well. I also replaced the torque tube.

I dropped in the motor, got it running and then prepared the car for paint. The original silver paint was nasty...faded and gray. I stripped the car of all of the trim work. I removed the rear windows, door mirrors, all lights and the front and rear bumper covers. I then made arrangements with a co-worker/friend to have his girlfriend paint it. She owned a paint shop. I had the chassis flat-beded down to her paint shop. I sat and looked at Porsche colors for a while and then decided black would look the meanest. She started working on it. Two months later it was done. That was a long two months!

In the interim, I located another interior from a fellow Porsche 928 owner's group list who lived in Tucson, AZ. My parents live out there, so I had my dad drive by and take a look at the stuff. He reported it worthy of the $400 the seller was asking, so I bought it and the seller delivered it to my father's house. This was a green interior, mind you, but I knew that I could repaint it. Then, a very close friend and fellow mtb'er, Eric, went to a race in west TX and offered to drive on out to Tucson to pick this interior up for me for a very small fee, like, $50. (I forget) He got back to Austin and when I got the car back from the paint shop, I repainted the green with black vinyl spray paint and installed it. I had some heavy duty black carpet and fab'ed some new floor carpeting/mats. I recovered the original rear interior quarter panels with black vinyl, glued in place with a generous coating of 3-M contact cement. I made a new shift boot out of the same vinyl material. I made new console side panels and door panel inserts out of some thin fiberboard. I put in a dash cover and a pod cover. It all came out pretty darn good!

It was around December of '97 and January of '98 that I finally got the car started and driveable. I drove the beast around for a while with some nasty transmission grinding. Turns out that the original ZF 5-speed has an inferior syncromesh design that wears out in no time and then downshifts are all but impossible. The solution was to replace the transmission with a later design that had the Borg Warner syncro's and had been modified to utilize an early style posi-traction unit. I put the new tranny in. By the way, taking a 928 transmission out requires major surgery. The entire rear suspension must be removed from the car. Halfshafts, coilovers, subframe, exhaust system, shift linkage...everything.

Soon afterward, there was a bad clunking sound coming from the tranny whenever I went around a corner. The posi unit was locking and unlocking and locking and unlocking over and over until the turn was completed. I had followed instructions with regards to what fluid to use. I bought another halfshaft and swapped it in for each side to no avail. I mounted a video camera under the car to take a look at what was going on. The video showed nothing unusual at all. This was an internal problem of the transmission.

I ended up yanking the tranny out. Uhhhmm...taking a 928 transmission out requires major surgery. (echo, echo) The entire rear suspension must be removed from the car. Halfshafts, coilovers, subframe, exhaust system, shift linkage...everything. (echo echo) I got good at this. I sent the tranny back to the specialist in CA and they said they could find nothing wrong with it. They sent it back. I re-installed it. It still banged. I called the specialist. With his direction, I attempted to modify the spacing shims for the posi unit. Still clunked. So, I had another friend bring his 928 over and we swapped his tranny and my tranny. Did I tell you I was getting really good at this 928 transmission removal and installation? Sure enough! My tranny clunked in his car and his tranny worked fine in mine.

Mark owned a performance shop at that time and he was a distributor of Redline products, so he came up with a concoction, a witches brew combination of transmission oils and additives. This worked like a charm! CRAP! Why couldn't I have started here? So, we swapped our transmissions back. Did I mention that I was an expert in 928 transmission installation and removal?

I drove around for the next year with the 750 Holley carb set up which absolutely SUCKED! It was difficult to start, stalled on hard braking or cornering (due to fuel slosh) and more than once, spewed gas out the top and onto the engine. Thank goodness there were no fires...well...there was one. In the garage. While tuning the timing. Had a backfire and it was a small fire that I was able to put out right way.

I replaced the wheels and tires in the summer of '99 with a set of Kinesis Super Cups. 18 x 10s in the rear and 17 x 9.5 in the front.

I put the SuperRam fuel injection set-up on in the summer of '00. I'd previously been running that single plane Weiand and Holley 750 which was a really poor set up. I found a Lingenfelter/Accel SuperRam for sale on a Chevy bulletin board and purchased it from the seller for $1700 (these units retail for $3100). Getting the SuperRam to fit under the hood without a scoop was a challenge. Marc Reveil and I welded up some copies of the conversion kit style motor supports, but we modified these to lower the engine about an inch. Very close to the steering rack/cross member now. But the hood shuts! And this keeps the car looking totally stock. Man, it runs like a bat outta hell now. Starts right up every time, has instant throttle response and doesn't care a bit about the g-forces during thrashing and tossing. My rear wheel torque is at 400+ foot pounds.

This is a silly post to the 928 rennlist documenting the hybridization procedure.

 

 

Here's a shot of the motor with the old carb set-up.

Here's a shot of the secret weapon hidden under the hood!

 

Here's a shot of the engine hanging by the hoist. I pulled the motor to replace the entire clutch assembly. I got 2 years out of the second clutch, which was a Centerforce II with the original, swap-kit clutch disc. I had the Aluminum racing flywheel turned and ordered a new Centerforce II pressure plate (specifically made for the McCloud hydraulic throw-out bearing) and a Centerforce clutch disc designed for a Chrysler application! Yep. I discovered that the Chrysler, 10.5 inch disc with a one inch, 23 spline center fits perfectly on the Porsche central shaft and mates perfectly with the Chevy 10.5 inch pressure plate and flywheel. As it turns out, the first Centerforce pressure plate was incorrect. I had managed to make it work, but it wasn't designed for a hydraulic throw-out bearing. As a consequence, it died an early death. Of course, 500+ ft lbs. of torque doesn't make the clutch's job an easy one!

I have another 928 "donor" car in the garage. Actually, I'm about to pass it on to another 928 enthusiast. It's an 82 that Marc Reveal completely stripped down to be a pure autocrosser. No sound deadening "tar" or nuthin'. No dash. NUTHIN! I picked it up in 1999, thinking...pull all the essential stuff off of the '79 and build a lightweight street racer. But I have since decided (yeah, it only took me 6 years!) that I have too much other stuff to do and not enough time.