Educate a n00b about Rx7's (FD)

[biomechanoid]

Before the flames at the general vagueness of my post, a little background information.

I'm building up a LS1 engine as a project, and want a nice looking and great handling vehicle to put it in when it's finished. I also don't want my engine in a typical LS1 platform (Camaro, Firebird, Corvette, Impala, etc.) From what others have told me, a "RX-7 FD" would be an ideal candidate for a swap, as engine weights would be about the same (220lbs aluminum block), the overall weight of the car would be less than any LS1 platform, there would be plenty of room for a t56 tranny without having to cut the frame, and also the wiring wouldn't be too much different from any Fbody LS1 swap. all those points have pretty much convinced me that I should set my sights on a RX-7 FD for my platform, but I have some questions:

1) what is a "FD" RX-7, and how common/uncommon are they (years made?)
2) about how much would I expect to pay for a rolling frame? (pretty much the body, wheels, and drivetrain- interior, transmission, engine, etc are optional)
3) are there any years that I should avoid in my search, or are all the frames pretty much the same.
4) about how much HP is the stock rearend good for? Desktop dyno's predicting my engine to be around 420HP/400TQ peak when it's completed.
5) is the steering mechanism vastly different from typical RWD setups? (this was the main problem with my CRX candidate aside from frame integrity)
6) what's the size drive shaft?
My project is intended to be a dedicated 1/4 mile car and weekend driver, so things like noise and street legality aren't too much of a concern.


-Justin.

[marshall]

You're stupid~!!

Just kidding.
1.) an FD is the chassis code for the 3rd generation RX-7; FD3S. They are not that common like most cars. They are getting hard to find. They were in production in the U.S. from 93'-95'.
2.) For a rolling frame with no motor/burned motor/blown motor, expect to pay a lot if the body and everything else are in good condition. I've seen them go as much as 14k with aftermarket wheels and no motor, but with a perfect body. Check ebay, i've seen many selling there that need to be "restored" Usually they go for no less than 5-7k, again depending on the body.
3.)They are all pretty much the same. 93's of coarse being the first year have small problems such as a very harsh bumpy ride, due to (in my opinon) the best stock race suspension made on a sports car. The 93's also had a lot of recalls on door panels and minor misc things such as this. 94' up are typically the best canidates for a good smoother ride and cleaner non rattling interior. But, you'll never find a cheap 94 or 95 model even with no motor.
4.) I've seen the stock rearend take as much as 550rwhp. But it really depends on who you ask. Most people will tell you no more than 400rwhp on the stock rearend. I personally know a few people that have torn their rear end apart on the highway with around 350-400rwhp.
5.) Not really sure what you mean, but here's my best guess. You will not drive a more race like car in your life. The steering is very good on these cars. I'd say it's different than most rwd cars just because of how well it handles in steering. With not much body roll and nible handling, it really is a blast.
6.)Not sure on this one.

The more and more i read your post though, i am thinking; Have you ever driven a good running FD3S rx7? You'll be pleasently suprized on the over all drive of the car, light-wieght and powerful, you'll think you're driving an indy car. You're prediction of 420hp and 400tq sounds nice and all, but just wait until you've driven an RX-7 with that much hp. :)

Not trying to talk you out of it, but I personally think it's a waste to do this on a car that is meant to have the Rotary engine. The car was built around it and is the heart and soul of the car. Just my opinion. Either way, good luch with your project, hope it works out for you and I hope I helped you out as much as I could with your questions. If you're curious and want to read A LOT. Go to www.rx7club.com and search for the member; Jimlab He is also doing a V8 swap in an FD3S, I think he has some of the most useful information on anything V8 and that of automotive info in general. Have fun!

-Marshall

[Hollywood]

for the money that you are going to spend on an LS1 swap, you could have a 500hp 13b in the Rx7.

[marshall]

^word

[dub-c]

oh ya, 7's = money pit :P but it will treat you right

[AusTexRex]

They're only money pits because we're too obsessed with modifying and keeping them incredibly maintained.
You COULD treat them like shit and still have them run well and rarely put money into it... but I'd castrate you

[marshall]

I miss my Fd, but love my new T/A

[Black Mantis]

Yea, I have a 421rwhp / 478rwtq LT1 camaro (95').....and even though I love muscle car's, I love RX7's just as much.

biomechanoid.....I was thinking what you were thinking but in the long run, your going to be paying alot to have the wireharness hooked up and having motor mounts installed on the Rx7 to handle that LS1 block.

My camaro is capable of running 10.7 - 10.9 in the 1/4 mile but I am still torn between selling my camaro and buying a 3rd Gen Rx7.

I own a 91' non-turbo Rx-7 now and i fell in love with the way the rotary engine whines up and the way it can handle. I can only imagine what a 400rwhp rx-7 twin turbo feels like.

[black rocket]

You know what kind of answer you expect... right?
Lose the Camaro...

[240Z2NV]

A buddy of mine has done TWO LS1 swaps in FDs. It is fantastic! Although you will get grief on the RX7 sites because of their loyalty to the rotary platform.
I have loved this car since it's rollout in '93. It is VERY difficult to find ANYTHING wrong with the car....it dents pretty easily in the body panels due to its race-designed light weight.
Many keep their high tech platforms and spend $$s with turbo mods etc; but, you can 'build' an LS1 much easier, for less, and they are less 'technically demanding'. I agree with the first response, ride in one. I have ridden in many stock TT FD3S, and in a 429rwhp 6 speed totally stock looking FD3S. Both are glorious; but, if you want shit-your-pants exhilaration and power, do the LS1 swap.
If you need more help with the swap once you find the donor car (i.e. needle in a haystack), save my email and I'll hook you up. I am doing the LS1 swap in a 240Z, and if I weren't 'into it' so far, I'd GLADLY switch paths and search for a 'donor FD3S'; but, bear in mind, they are very hard to find! I can't even source a pair of seats (FD3S) for my 240Z hybrid after months of searching! Direct email: [email protected]

[AusTexRex]

There is an FD with a blown motor for sale in the sales area:
http://www.rx7forums.com/forum/viewtopic.php?t=414
Good luck.

[FadedFD]

Sure he can build a 500 HP 13b but he wont have the reliability of a LS1/T56 FD. The LS1 has amazing gas mileage for it's HP as well. The 6th gear really helps. Go do a search for Hinson Supercars for LS1RX7 engine mounting kit. You will need to give them your stock sub frame as a core and wait about 3-4 months. Don't go with the Granny's kit. I heard they suck major.

Justin