STRIKEMASTER

I found someone selling a -79 Mazda RX-7 shell ( no engine ) near me for $799!! I wonder if anyone has info on putting a 928 engine in a RX-7. I had a RX-7 years ago and it was a really hot car for only 1300ccS. A 4.7 Ltr 928 engine would make it hyper-sonic!! BUT can it be done??? I see threads on GM mills in sharks but how about giong the other way??

G8RB8

Yes, but the offspring will be sterile, impotent, generally bad mannered and will not live long.

G8RB8

Seriously the engine in an RX7 is ridiculously light for the power output as well as very small.

IcemanG17

I'd say this is a HORRIBLE idea......the strength of the Rx7 is light weight...the 928 4.7L engine is rated at 234hp or 300hp (euro)..but its over 530lbs.....put that much weight in the nose of an Rx7 will not work well at all....it won't handle worth a damm.....and honestly early Rx7's don't handle very well anyway.....they are extremely loose in race trim......

Speedtoys

There are numerous kits for SBC's in RX7s...so it can be done, time to get those fabrication skills up to date.

Nicole

I'd rather get an 86 or later RX-7 with the upgraded rear suspension (I think they were called GXL in the US - Euro models came standard with that set-up) and keep the rotary engine.

I miss my 86 RX-7 - it was a blast to drive!

Thanks, Jeff for letting me drive the RX-8. It reminded me of the good old times.

tailpipe

From what I have read there is a 5.0 lt 5 speed swap kit thats a pure bolt in and from what I have read its almost like they were made for each other. Dont bother with the porsche motor its not worth your time or money.

Speedtoys

If you do any of these...do 78-79 cars.

They have some significant extra body bracing that 80-83 did not have.

I raced 1st gen's for years, won most. Those were the days.

Adamant1971

The first gen rear ends were very strong as well. I have owned 6 of them. But I would go for an 84 or 85 gsl-se. Bigger brakes and better suspension.

As far as weight up front, you can move the battery to the rear, delete the oil cooler or use a lighter unit. You should be able to maintain a 55/45 with it. Not quite the 50/50 as with the rotary.

Speed toys is right the early cars has significant bracing between the rear inner fenders where the storage bins are. Can't remember where else.

I personally would like to put a boosted 20B in a 928. Yep I said it.

STRIKEMASTER

Thanks for the feedback guys. Just a wild-a$$ thought on my part. I agree with you Adamant1971, a 20-B would be the way to go. Newer RX-7s were designed to take the 20-B and whey can be worked up to well over 300HP, so one should fit in a '79. Now all I need is $5K for a 20-B engine. ;-)

kevinlieb

This would be a disaster. Keep in mind the rotary is meant to rev high and make its power in high rpms. The shark: the opposite. With the stock gearing I think the car would barely move.

Imo000

The RX-7s weren't really 1300cc. They run like a two stroke and guzzle gas like one too. A fair comarison would be of an engine with double the displacement. A 3.6L V6 is what they really are.

kevinlieb

I was between a newer RX-8 and the 928 when deciding on my car. I love the rotaries and it is a very different and special car in its own way but in the end decided that the 928 had more character.

Best to have one of each: not try to make a thoroughbred into a greyhound or vice versa.

IcemanG17

You need to talk to Jeff....he has both.....raced Spec7 for years.....then bought an RX8.....then a 928.....

I am kinda backward....started with a nice S4....ended up with a few different 928 racers.....then bought a Scion FR-S, which sorta is the modern RX7 or 240Z

Speedtoys

Tearin up the track is the RX8s job.

Two entirely different cars, and modes of driving.

...and one was meant to be a track beater...the other wasnt.