It's taken me 4+ months but I now have my 1979 RX7 small block Chevy/T5 transmission swap running and driving. The vast majority of that time was spent looking and waiting for a great deal on the engine and transmission and aquiring random parts. Actual time spent completing the swap was 4-5 weekends.

I wanted to find an engine that was still mounted in the donor vehicle so that I can see it run before buying. Another requirement was it had to have a short water pump and accessory drive set up that is required for this swap. My patience paid off when I found an ad on Craigslist for a 350/4-speed that was still mounted and running in a Chevy 2WD pick-up. The same seller also had a Camaro T5 transmission for sale. The engine ran great and we struck a deal. For $500 I got the complete engine, flywheel, clutch, bellhousing and T5 transmission.

Engine brackets, oil pan and transmission crossmember were ordered from Granny's Speed shop. The brackets and crossmember looked very well fabricated and everything fit perfectly with plenty of clearance around the engine and bellhousing. I was shocked to see how much room there was in the engine compartment and transmission tunnel.

For exhaust, I used iron manifolds and dual 40 Series Flowmaster exhaust from my friends 1963 Chevy II(He's now running fenderwell headers and glasspacks). The exhaust terminates right before the axle. Sometime soon, I will weld in a Y-pipe and run single exhaust to a muffler mounted in the stock location.

I tried to use the stock clutch master cylinder but it didn't quite have enough displacement to fully release the clutch with the stock slave cylinder. A 7/8 inch bore Wilwood master cylinder was ordered from Summit Racing along with a 36" long -3AN hydraulic hose and an adaptor fitting for the slave cylinder. The new master cylinder worked out perfectly but the hose was a little to long. A 24" hose would have been a better fit.

The stock radiator proved to be marginal so a 22 x 19 aluminum radiator was ordered from Summit Racing. I fabricated a cradle and top clamps and mounted the radiator with rubber isolators. The stock fan from the donor truck was trimmed several inches for hood clearance. Before summer rolls around, an electric fan and shroud will be installed. But for now, the current set-up runs cool enough.

Was the swap worth it? Hell yes! Revving the nuts off the little 12A rotary was fun but very disapointing as far as performance goes. It was cool and sounded great but definately not exciting. The V8 completely transformed my RX7. Now it's raw, loud and ridiculously fast. Handling actually improved. Cornering power and balance feels about the same but now I can steer with the steering wheel and the throttle. It's an absolute blast to drive. Very predictable and controllable at the limit.

So far I have spent a grand total of $2200 on this project. That includes the car itself. I've done lot's of swaps and power adders, mostly muscle cars, 240SX/SR20's, EG Honda's, Turbo Miatas etc. This was by far the easiest and has the most performance potential. If you have an SA or FB that needs a rebuild, I highly suggest a V8 Swap.

Next on the list is a complete rebuild/upgrade to the suspension, a roll cage and a Holley carb/aluminum intake. Then I'll take the whole car apart for bodywork and paint.

I left out a lot of the details to make this swap work. If there is any interest, I can post pics and give more in depth details about the swap.

 

Well done, I'm at 10.5k on my swap and it doesn't even run :p

 

Wanna race?

 

Wow, that's a major return on investment, congrats.

Please do.

 

I'll pass on the race for now. I am still dialing things in and have to rebuild the suspension before I really get on it.

Here's a pic of the first time the engine and transmission was lowered into my RX7. I thought there was no way this beast was going to fit, and if it did, the suspension was going to bottom out under all the weight.

 

Engine painted and bolted in for real. Tons of room everywhere, especially the transmission tunnel and the passenger side engine compartment.

The suspension sits 3/4 inch lower in the front and 1/2 inch lower in the rear. The rotary is engine is fairly light but everything that bolts to it is freakishly heavy! I estimate the weight gain at 150 to 175 pounds. My combination has a very heavy iron bellhousing, intake manifold and water pump. When I replace those iron parts with aluminum, that will take around 60 pounds off the front . Headers will be good for at least 25 pounds weght reduction and a 12 inch flywheel will save another 15 pounds.

 

The engine came with a 10 spline clutch disk so it was replaced with an 11 inch, 26 spline Zoom disk to fit the Camaro T5 transmission. The stock pressure plate was bolted on top of the Zoom disk.

The pilot hole in the iron truck bellhousing was too large for the T5 transmission. The solution was an aluminum adaptor from Trans-dapt

 

The clutch slave cylinder was machined from a piece of 2 x 2 x 1/4 inch angle iron. The mounting holes on the slave cylinder was slotted to provide a small amount of adjustment. The pushrod is a stock RX7 part. This set-up looks a little flimsy with a single attachment to the bellhousing but it's actually rock solid.

 

The engine came with a points style distributor. It was replaced with an HEI distributor from Summitracing for $89.99. One wire hook-up and everything(including the coil is under the distributor cap. I required a little bit of clearancing on the firewall and hood latch.

 

A throttle cable from any 1970's or early 80's GM vehicle will fit with some trimming of the cable and housing. A pain in the *** job so I decided to use this kit from Autozone. The bracket and return spring came from an '80 Oldsmobile.

 

I don't have any pics of the driveshaft but it was built from the front half of a junk yard 1986 Camaro driveshaft and rear flange from an RX7 driveshaft. They were almost identical in diameter so the driveline shop had no trouble mating the two. Cost was $120 including new u-jounts. Way cheaper than Granny's Speed shop.

Well that's all I can think of for now. If anyone has questions, I do my best to answer.

 

Is that stock Mazda motor mounts under the front of the chev motor???? What oil pan mods did you do???? Going to run it at the Bogus Basin hill climb???? Thanks.

 

Great job on your build it's looking good.
I also stuffed a small block in my 85 gsl and
Can't complain it's a 350 Chevy with the granny's
Headers,edelbrock intake and carb and a lunati cam.

 

More pictures!!!!!

 

Sorry it's been awhile since I've checked on this thread. I've been distracted by other hobbies, shooting guns and fly fishing.

The oil pan came with the swap kit from Granny's Speed Shop. Not the best qualty oil pan, ugly welds, but it did fit with no issues and has not leaked.

Over the weekend I installed an electric fan and relocated the radiator further forward (ahead of the round tube crossmember). The temps now stay below 210 degrees no matter how hot the weather is. The only problem is that the radiator sticks out of the grill a couple of inches. I am planning to lay-up a fiberglass air dam so that won't be a problem for very long. When the air dam is done, I will lay down some paint. I'll post some more pics when the paint is done.

 

what axle did you use

 

Did u have to do Any wireing? Like with the harness

 

There typically isn't any wiring on a carb'd car