Originally Posted by
www.grannysspeedshop.com
...Welcome to the home of the V-8 powered Mazda RX-7, where we've designed, built and raced muscle cars powered by both piston and rotary engines for over 35 years. Since our 1st RX-7 / V-8 conversion kit sale back in 1995, we have sold over 3500 kits worldwide, with customers in Argentina, Australia, Brazil, Canada, Dutch Carribean, Fiji, Germany, Greece, Guatemala, New Zealand, Pakistan, Puerto Rico, Trinidad, Virgin Islands, and thousands right here in the USA.
...This is a very easy engine swap. Although our instructions may seem a bit long, don't be intimidated- the swap is actually quite straightforward. Most people would agree that installing a V-8 is probably easier than re-installing the rotary engine. Most hotrodder types are able to complete the mechanical part of this swap with little or no direction at all.
...The RX-7's layout and structure is well suited to engine conversions. The rotary engine's eccentric shaft centerline is way up in the center of the rotary engine, dictating a much higher transmission location than that of a piston engine. The net result is that Mazda designed the RX-7 with a HUGE transmission tunnel, big enough to fit even the monster T-56 6 spd manual transmission which was used in the Viper and Corvette. The rotary engine's low torque output required Mazda to use a very heavy flywheel and a high rear gear ratio, a combination of factors that combined induce large amounts of stress on the RX-7's rear axles and hubs. Mazda planned accordingly, and designed plenty of strength into the RX-7's rear differential/axles/and hubs. Experience has shown that the stock NA RX-7 components are strong enough to withstand low 10sec 1/4mi passes, a feat that requires around 500hp.
About 1/2 way down this page you will find links to pages containing specific info, on-line instructions, and parts lists / pricing.
Be sure to check out our RX-7 Conversion Index, a page of 40 or so links to pictures of various RX-7 conversion projects. Please e-mail us if you have one you would like to add.
...Think the v-8 will forever ruin your handling? The August 2005 issue of Grassroots Motorsports Magazine will features quite a few V-8 powered RX-7s that entered their $2005 Challenge event in Florida. The premise of the event is to build the best handling, best appearing, and quickest car possible for a total budget of $2005., including the price of the car and all components. You will be surprised at the wide variety of entrants and how creative they are. Check out the August issue for a feature on this year's challenge winner, a FORD POWERED 2nd gen RX-7!!! For a free copy of the magazine or to check out this year's $2005 challenge results, go to the Grassroots Motorsports website.
In the 2004 event, of a total of 76 cars that participated, a total of 9 RX-7s took part in the event, 5 V-8 powered and 4 rotary powered. In the drag race portion, all the V-8 RX-7s finished ahead of the rotary powered cars. No surprise here. The quickest V-8 RX-7 recorded a 12.636 ET, the quickest rotary's ET was a 14.323. What DID suprise a lot of sports car people is the results of the autocross competition. The quickest RX-7, a V-8, finished nearly 4 seconds ahead of the quickest rotary version. Among the 9 RX-7s present in the autocross, V-8 power captured 4 of the top 5 spots. Don't listen to those who tell you that a big V-8 will ruin your handling!!!
Daryl Evans's ZZ4 powered RX-7 solo car was last years local, regional and Canadian Western Champion in E Mod.
Rotary Vs. LS1
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im not a fan of ford. and its not just convertibles that can benefit from it, the coupes or hatchbacks(depending on how you look at it) can also easily benefit from it.
Ive looked into it already the stock swapped 5.0l in a fc will do 13.6's in the 1/4. thats not a bad starting point.
ill be waiting 
! Who needs torque???
