About a year ago, I decided to build a 2.9L stroker to relieve the wheezing 245-k mile factory engine in my 1989 E30. As far as I could tell, the engine had never been apart--I have records back to new through six (!) meticulous owners, showing lots of service and repairs, but no mention of an engine rebuild. Plus it still had the failure-prone head bolts, which was another indication of its virginity, as those would almost certainly have been replaced. But it was a really tired, high-mile virgin.
Since I wanted to keep the car drive-able and didn't care about numbers matching (maybe this will one day matter for E30s, but I hope not), I found a give-away engine nearby, brought it home, took it apart, and took the block and head to my machinist, Chuck (C&D Machine, Kirkland WA--highly recommended), along with a Bimmerheads 2.9 stroker kit. The kit contained an S52 crank, Molnar forged rods, 86mm Ross pistons, and ARP fasteners. I dropped everything off in December 2021. Thus began an odyssey.
The free engine was worth every cent I paid for it--a few days after drop off, Chuck called to say the block was junk. The next day, he reported that the head was also junk. I found another block that turned put to be usable at a friend's shop, but I had to go through five (!) cylinder heads to find one that was usable. Three had cracks, and one had been machined at an angle other than 90 degrees to the block, so the head rode higher at the front than the back. Number five was the charm--after I spent most of January hunting down every 885 cylinder head in the PNW, shelling out hundred dollar bills like chicken feed.
Some time in February, Chuck called to report that the pistons sat too low in the cylinders at TDC. I called Bimmerheads, and they said they'd had some problems with the sizes of the Ross pistons, and that they had switched to CPs (Carrillo). They sent me these as a replacement set and I returned the Ross set to them. Chuck confirmed that they fit, but we had already burned about two months dealing with broken or non-fitting parts. Nonetheless, I got all the stuff back by March--an assembled short block, and a ported head with a 274 Bimmerheads cam (reportedly made for them by Ireland).
Spring and early summer got filled with putting the rest of the engine together and sourcing the Megasquirt, injectors, and ancillary pieces, but I finally pulled the old virgin late summer and dropped in the new engine in October. I then had to make a make/buy decision. Since I had zero experience programming a Megasquirt and would be firing-up a new engine with a green cam that had been gobbling big wads of cash, I went the buy route and hired out this job to Patrick at Midnight Motorsports in Seattle (highly recommended). Shortly before Thanksgiving, I watched as Patrick fired up the car on his own Megasquirt tune running in the cam for 20 minutes. He broke the engine in over the next few days, street-tuning the motor via laptop. His goal was to provide a conservative street tune I could use for break-in mies, after which I'd get a power-tune on a dyno. I picked the car up and was pretty happy with how it ran, though I was instructed to be gentle for the next thousand miles, changing out the break-in oil at 250 miles and doing another change at 1000. The car felt very torquey and strong up through about 4.5k rpm, at which point the car stumbled, but I attributed this to the conservative street tune that we'd sort out at the dyno.
I was wrong . . . [to be continued]
Since I wanted to keep the car drive-able and didn't care about numbers matching (maybe this will one day matter for E30s, but I hope not), I found a give-away engine nearby, brought it home, took it apart, and took the block and head to my machinist, Chuck (C&D Machine, Kirkland WA--highly recommended), along with a Bimmerheads 2.9 stroker kit. The kit contained an S52 crank, Molnar forged rods, 86mm Ross pistons, and ARP fasteners. I dropped everything off in December 2021. Thus began an odyssey.
The free engine was worth every cent I paid for it--a few days after drop off, Chuck called to say the block was junk. The next day, he reported that the head was also junk. I found another block that turned put to be usable at a friend's shop, but I had to go through five (!) cylinder heads to find one that was usable. Three had cracks, and one had been machined at an angle other than 90 degrees to the block, so the head rode higher at the front than the back. Number five was the charm--after I spent most of January hunting down every 885 cylinder head in the PNW, shelling out hundred dollar bills like chicken feed.
Some time in February, Chuck called to report that the pistons sat too low in the cylinders at TDC. I called Bimmerheads, and they said they'd had some problems with the sizes of the Ross pistons, and that they had switched to CPs (Carrillo). They sent me these as a replacement set and I returned the Ross set to them. Chuck confirmed that they fit, but we had already burned about two months dealing with broken or non-fitting parts. Nonetheless, I got all the stuff back by March--an assembled short block, and a ported head with a 274 Bimmerheads cam (reportedly made for them by Ireland).
Spring and early summer got filled with putting the rest of the engine together and sourcing the Megasquirt, injectors, and ancillary pieces, but I finally pulled the old virgin late summer and dropped in the new engine in October. I then had to make a make/buy decision. Since I had zero experience programming a Megasquirt and would be firing-up a new engine with a green cam that had been gobbling big wads of cash, I went the buy route and hired out this job to Patrick at Midnight Motorsports in Seattle (highly recommended). Shortly before Thanksgiving, I watched as Patrick fired up the car on his own Megasquirt tune running in the cam for 20 minutes. He broke the engine in over the next few days, street-tuning the motor via laptop. His goal was to provide a conservative street tune I could use for break-in mies, after which I'd get a power-tune on a dyno. I picked the car up and was pretty happy with how it ran, though I was instructed to be gentle for the next thousand miles, changing out the break-in oil at 250 miles and doing another change at 1000. The car felt very torquey and strong up through about 4.5k rpm, at which point the car stumbled, but I attributed this to the conservative street tune that we'd sort out at the dyno.
I was wrong . . . [to be continued]
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