Did u know that u can stuff a V-8 into any RX-7?

I was looking around online and happened to find a website "www.grannysspeedshop.com" that specializes in V-8 swaps for all 79-95 RX-7's. I own a 83' GSL RX-7, and am planning on putting a 5.0L Ford into my lil car, which runs mid 13's on a stock 5.0L!!! I have a history of modifying Mustangs with 5.0L's and cant hardly wait to see the results of one in a RX-7. :smoka:

It'll be great in a straight line, assuming you don't break the tranny or rearend. In the curves, the heavier motor with a greater amount of weight high up will upset the balance. Now, some guys will argue that you can use counterweights, or move the battery to the back to offset it, but there's more to handling than a 50/50 weight ratio, its where is the weight relative to the center of gravity. Think of it in this extreme: if you took a '71 Caddy, added some lead bricks to the trunk until you got a 50/50 front/rear ratio, it still would handle like a boat because the weight is further away from the center of gravity.

There are guys out there that have used Granny's kits, if you go to any of the RX-7 forums (you can find 'em on my Links page) you'll find guys more than willing to share info.

You must not have read that site much or read about Jim LaBreck's car then. His in particular will not only be incredible in a straight line, but will handle at least as good as a 13b powered RX-7. I don't believe that Granny's site has a whole lot of info on his car in particular, but if you search the archives of the RX7 Forum you'll find a few good posts about it with pics. His will still have 50/50 weight distribution, weigh not much more than stock if at all, will be 4 corner balanced, have nearly 600hp, and be reliable. Plus he gets the benefit of a T56 and TONS of inexpensive aftermarket parts and support unlike rotaries do presently. On top of that it'll also be cheaper than a 20B conversion. Well, not Jim's since he's getting his motor built up like crazy, but just the conversion in general. It's not necessarily the best way to go, but it's definately unique and easily do-able. I'd still personally go for the 20B conversion, but at $36k it's damn expensive.

First off, I'm on the boards daily, I've been a member since they started (I'm not one of the post whores, yet I have over 600 posts since the last time the site was hacked and we lost our counts), and I have read up a lot about Jim's car. And nothing against Jim, but it still isn't on the road yet as far as I know, so to date its all theory. I'm not saying it won't happen, just that it hasn't happened yet. And if memory serves, Jim's final cost was going to be approaching the 6 figure mark, primarily due to the special build on the motor.

Secondly, I'm not saying that you can't make a V8 RX-7 handle well, I was simply pointing out a fact of physics that is often overlooked or ignored when the debate comes up. To restore all the moments of inertia back to stock takes careful planning and good execution of the motor swap, and from what I've read Granny's tends to oversimplify it. I believe that even Jim would concur with that statement.

Peace

Well yeah I'll have to agree with you about Jim...he's the type that takes everything to the next level. I remember him back on the Big List about 3 or 4 years ago when he first started talking about doing the 20B conversion. He has more money to mess around with than I'd care to fathom....must be freekin' nice. What I think a lot of people don't realize about the 13B-REW is that there are two turbos, heavy cast iron manifold, that heavy ass pre-cat, and other accessories hanging off the block that makes it pretty heavy overall. The block itself is super small and light which makes n/a rotaries incredible handlers, but on the 13B-REW there are a lot of other dohickies that add a lot of weight. I don't think Jim's estimations on his particular car are too far off and the guy's at Granny's did weigh their car as well and got very similar results. I honesty think that it's blasphemy to put a non rotary engine in a RX7, but I also have to respect the hot rodding spirit that the project has and it's potential. Now if I can just get Jim to let me borrow some of that money :D

I tell you the converson I don't like is the SP Engineering Supra-7. That big ol' 2JZGTE in that engine bay just doesn't quite look right. The engine itself is a great piece of machinery, but it's just huge, heavy, and looks out of place. I've also heard of another company who swaps in Grand National engines into RX7's, but I can't find any info on them at the moment. I remember they used to have ad's in the back of R&T and C&D a while back. Also there's a guy on the Forum who has a Ford SVO Mustang turbo 4cyl powered 1st gen that's pretty sweet. I have a few vids of it and it hauls butt pretty good. My favorite conversions though are Mariah Motorsports 2nd gen 20B's. They're totally beautiful and aggressive looking.

RX-7 Heavan here in NZ has put an alloy block 406 into a Bat (3rd GEN) RX-7. My brother (who works there) said it is the fastest bloody thing he has ever been in. The engine is sprint car material, 6 speed g/box etc, apparently about $60K (NZ) worth. Be interesting when finished, and if it handles?

Ive been sort of keeping up w/ this whole debate as well. Altho I like the rotary, we cant deny the fact that its a pain in the rear maintenance wise and a very temperamental motor. With that I think the whole V8 swap is a cool idea...especially for those who love driving their car daily and possibly taking short trips. Can you imagine getting stranded somewhere w/ no rotary specialists in the area? Talk about headaches, however, w/ the V8 swap trips can now be worry free.

I agree w/ efini when he mentions most ppl dont include the other components. Rotary vs the V8, yes its MUCH lighter but when you factor in the weight of the turbos, intercooler along w/ the LS1 motor less the cast iron manifolds I dont think its damn nearly as different in weight as ppl think. Even Jim mentions maybe 50# heavier if that.

Is 50# worth the +'s of V8 simplicity and performance product support right here in our country? I think so.

Just recently, Ive read a Z06 crate motor can be had for about $7000. Holy craaaaap can you imagine that? 405HP/400# torque from a N/A motor that can be worked on at any Chevy/GM dealer. How can that not sound good?

I would have to agree with 3rdGanLuvr, i wouldnt wouldnt want to get stuck in the middle of nowhere with my rotary. And the thing about the weight difference of a 3rd gen TT rotary compared to a LS-1 or LT-1 is very minimal, about like 50-100 lbs difference. It doesnt affect handling at all, i have a friend in Phoenix who completed his LT-1 6 speed conversion on his 94' RX-7 and believe me, its way better than before. Ive had the pleasure of driving it both with the rotary and the V-8, and there in no comparison, the V-8 is king in the 3rd gen body. I own a 83' 1st gen RX-7, with a 5.0L Ford going into it shortly and can hardly wait to have it completed, but im going over the motor and tranny very carefully to make sure i get my performance needs.

Originally posted by rezdog_420
i have a friend in Phoenix who completed his LT-1 6 speed conversion on his 94' RX-7 and believe me, its way better than before. Ive had the pleasure of driving it both with the rotary and the V-8, and there in no comparison, the V-8 is king in the 3rd gen body.


No sh!t? Any chance on getting some pics for me? Does he frequent these boards? I'd like to ask him some questions about it. Im definitely serious about goin this route when the day comes I need a motor. Altho I dont want to jinx myself....lol......hopefully it wont be too soon. Besides I kinda like my rotary.

Hinsonsupercars.com for the ls-1 conversion, yeah screw high up keep cost on the B motors, do the v8 conversion!!!!

www.torquecentral.com has a v8rx7 forum that can help with any questions you may have

this thread is from 2002, its almost 2005, DON'T BRING UP OLD THREADS

Dont Tell Me What To Do!!!!!!!!!! Whats The Point Of Having These Posts To Begin With If We Cant Post On Them???

please don't flame at other members; a thread this old, if it is important enough a topic, should be restarted because often (like in this case) those who partook in the thread either very frequently visit this site, or no longer do.