I know most of yall don't like the idea of taking the rotary out of a RX7, but this is still my game plan after all. I'd prefer to find a RX7 without and engine and with front damage, as I'll be doing some body work to it also.

What I need to know is if it's been done in a '93+ RX7, and if not, how would the the install in an older RX7 compared to installing it in the newer one?

Another question of mine is what the strength of the rear differential in these cars is. I'll probably be putting down around 500hp and around 600ft/lbs of torque. I'm not going to pretend to think that the stock one could take that on slicks or anything. What I'm wondering is if that the stock rear could hold with a street driving, non-slick using, 400 or so hp for a while?
What upgrades are avaliable for the rears of these cars?

Since I dont' really want the engine or trans of the RX7 drive train, what models should I be looking for. Are the NA car's rears/bodys/frame/supension/interior the same as a Turbo? Because if they are, I'll take one of the cheaper cars as my base.

I know I have a bunch of questions, and I'm sure this will be a DIFFICULT project, but it seems feasible and would be really fun in the end. Thanks again.

- Matt

 

To my knowledge, a 3.8 has never been put in an FD. I've seen it mentioned before, but its never gone beyond that.

Also, there are no NA FD's; they are all twin turbo.

 

So what are the advantages of a 3.8 buick grand national? I know very little about this engine. Its turbocharged, right? How much does it weigh?

It just seems like old technology to me. Those things came out in the 80's?

 

Dont be dissing old school engines...the GNX's are sleepers from the factory I have a video of 2 of them raping a Viper GTS...

They are very simular to the Supra's going BPU...also Jay Leno has one...of course they handle like a lead brick...but what 80's american car doesn't?

I would be concerned about wrecking the balance on a RX7 more than anything...

 

These engines have many advantages. First, I think it's size will allow it to be put into a FD RX7. I don't think that weight/balance is an issue as I've read that the stock rotary engine weighs in at like 365lbs, which these engines should not be much more than.

Secondly, for around 5k I can have motor than can drive around town with 400hp and 500ft/lbs. of torque at 17psi, or at the track with racegass with 500hp and 600ft/lbs. of torque at 27psi of boost!!!

Lastly, I like large displacement american muscle, turbos, and I also REALLY like the styling of the RX7 with a few of the avaliable body mods on the market. I feel that if I found a beat enough '93 that I could build this car for around 14.5k. If I could find traction and the rear end holds, it should do 10s NO problem, and even then should 130+mph at the end of the track.

- Matt

 

I think your biggest problem would be getting turbo manifolds made that would clear the frame.

 

I'd rather put in the 3.8 than an LS1. Those engines demand respect!!!!

 

its been done before and it didn't seem to run to well at the strip- Jose's Rotary put a gnx motor in a 93 rx7

 

4 Things I want to do when I have the funds:
Stick a 20b in an MKIV
Stick a 20b in a GN
Stick a 20b in a C5
Stick a 13b in an S14 or S15

Did I miss anyone?
I believe that it is only fair

 

And you will just ruin 4 cars by doing so.

The GN engine is badass, no doubt about that.

 

what would be the objective you are trying to achieve in putting a 20b in those cars?

the 2jz engine is one of the most potent engines ever created.

 

A 20b with dual or tri T78s or T88s will beg to differ.....

A well ported 13b with a single has been known to pull 600-700hp

Let's see....a 20b with STOCK twins pushing 15psi can pull 550hp.

A 20b with one single should make 650-750hp
A 20b with dual singles can make anywhere from 700-900ish hp.
A 20b with THREE singles HAS been proven to make 1000hp.

Yeah, I know. It's a waste of a perfectly good rare engine, but hey, I like to prove points, and if I had the flow to do it, I WOULD do it, and I don't mind pissing off each of their communities while doing it

and JUST for you, I would stick a 20b in an AMG SL

 

My objective? That I can be different, too.

A 20b can push 550hp on 15psi off the STOCK twins. Yeah, a 20b has no potential.......

 

And a 2JZ with just ONE single and the STOCK engine HAS been proven to make 1000 hp.

...And it has a nicer exhaust note.

 

Well, the singles on that FD with the 20b look pretty small.

Besides, you know we don't need monster PSI. Just monster flow. Hence why guys with 13b singles can run les than 20psi and still make it in the 9s. Adam Sawatari, for example, was only pushing about 16lbs and was in the 9s.

The 2JZ is your opinion. I can post a vid to a 20b FD here running down the track and make people drool at it. I've heard a few 20b (In person and in video) and they sound BETTER than any 2JZ I've ever heard. High pitch and growly....almost like an F1 , and I DON'T think you can argue with how an F1 sounds. My buddy and I were present at the starting of a virgin 20b at KD rotary. It was.......

 

To answer the original question, yes, the stock differential should be ok for 400HP, but 450ft lb of torque, getting kind of iffy. Don't abuse it too much and you should be ok, but that would be hard . There are upgrades however, Kaaz makes an upgraded differential that is popular, you can also get chromoly axles and a stronger power plant frame, all these are completely bolton. Rotary Performance makes the axles, the Kaaz you can get from lots of places, and Mazda(speed) makes the upgraded PPF. That combination should be good for 600HP 500ft-lb on street tires, again as long as you don't abuse it too much. I'd call up rotary performance and ask them, they will know exactly what the setup can take. Post pics we want to see.

 

The Buick 3.8 was a neat engine when it came out but it isn't much more reliable than a rotary and that 4800 rpm redline is reallllly cool.....but they can make great power, unfortunately there's usually more done than meets the eye. To each his own though.

 

GNX-7

Here is a Buick V-6 turbo in a second gen, but no luck finding one in a 3 gen.

Joses rotary doesn't have any information on the swap, but I seem to remember it back in the day too