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cosmick · 10-03-2014, 10:45 AM

So my S-10 progress is in the newb introductions part of this site, but yesterday I brought home a cherry '83 RX-7.
Those rotaries are supposed to average mid 20s at best, occasionally spiking to 30. But rotaries carbon-lock, and the cost of gaskets and apex seals exceeds the cost of a used piston engine.
So because my dad had a '96 Bonneville that did 35 MPG with the lockup torque converter not locking, I'm going with one of those engines. It's a 205-HP 3.8L V6, also found in '96-'02 Camaro / Firebird with manual transmissions.
I've talked to a PCM expert, this deal is good.
Classic V8s fit, so this swap will fit.
I see a smaller, lighter car with less drag than the "new" engine ever came in, and stock gearing for those cars gave as low as 1800 RPM at 65 MPH in the 'maro / 'bird, also known as the F-twins.
The five speed has a 0.72:1 OD, the 185/70R13 tires are 23.2" dia., and available axle ratios include 2.286:1, 2.412:1, 2.5625:1, 2.7333:1, 2.929:1, 3.077:1, and up into the mid-4s, because the RX-7 is getting a 7.5" rear axle from my '87 S-10, which is getting a Ford 8.8" rear axle.
I found a decent urethane airdam for $ 136 new, but that will have to wait until the car moves under its own power again. Today I unload it from the trailer, return the trailer, and begin pulling the rotary for disassembly.

10-03-2014, 10:45 AM	#1 (permalink)
cosmick Experienced UAW Mechanic Join Date: Sep 2014 Location: Bear Lake Posts: 363 Thanks: 7 Thanked 73 Times in 63 Posts	'83 RX-7 from <30 to 50+ So my S-10 progress is in the newb introductions part of this site, but yesterday I brought home a cherry '83 RX-7. Those rotaries are supposed to average mid 20s at best, occasionally spiking to 30. But rotaries carbon-lock, and the cost of gaskets and apex seals exceeds the cost of a used piston engine. So because my dad had a '96 Bonneville that did 35 MPG with the lockup torque converter not locking, I'm going with one of those engines. It's a 205-HP 3.8L V6, also found in '96-'02 Camaro / Firebird with manual transmissions. I've talked to a PCM expert, this deal is good. Classic V8s fit, so this swap will fit. I see a smaller, lighter car with less drag than the "new" engine ever came in, and stock gearing for those cars gave as low as 1800 RPM at 65 MPH in the 'maro / 'bird, also known as the F-twins. The five speed has a 0.72:1 OD, the 185/70R13 tires are 23.2" dia., and available axle ratios include 2.286:1, 2.412:1, 2.5625:1, 2.7333:1, 2.929:1, 3.077:1, and up into the mid-4s, because the RX-7 is getting a 7.5" rear axle from my '87 S-10, which is getting a Ford 8.8" rear axle. I found a decent urethane airdam for $ 136 new, but that will have to wait until the car moves under its own power again. Today I unload it from the trailer, return the trailer, and begin pulling the rotary for disassembly. Last edited by cosmick; 10-22-2014 at 05:48 PM..