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rockhound72 · Posted: Sun Dec 02, 2012 2:48 am Post subject: Too buy or not to buy.

OK, there is a mid 80's RX-7 down the road from me that the owner wants about $3500 for. The kicker is that it is a 5-speed with a 350 V8! More or less a jet pack with wheels. My concern is whether this little car could withstand that type of power, or will I be shoveling $$$$ into it to replace parts that are falling off. I live in Arkansas, so it's pretty common redneck engineering around here. Just last year I saw a late 80's Mustang jacked up and converted to 4 wheel drive!

the_mad_electrician · Joined: 16 Nov 2009 Posts: 1073 Location: Central Georgia

SBC conversions in RX-7s are actually very common. Unlike a 924 that starts off with a slight rear weight bias thanks to the tranny in the back the RX-7 has the tranny connected to the engine so with the SBC you end up with a nose heavy car. Fine for straight line cornering might be a bit difficult. Unless it is an LSx engine that's all aluminium then the weight differance would not be that great.
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81 924 N/A

2004 Ranger "Edge"

2005 Mazda 6

fiat22turbo · Joined: 18 Jan 2006 Posts: 4040 Location: Portland, OR

With a 2nd gen RX-7 and a SBF with aluminum heads, water pump, etc the weight balance is pretty close to perfect. I think the figure was around 53% front weight bias.

The transmission and rear end are stout enough, for sporty driving without drag starts. The turbo parts are slightly stronger.

The first gen cars are fine, just slightly less strong, but the solid axle rear end can be swapped for a narrowed 9" if the stock one blows up.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)