RX7 SBF. What gen?

I just bought a complete (except wheels) 1990 RX7 convertible for a very reasonable price. Only gripe I have is that it's an A/T car. I'm yanking the motor for another project, hmmm wonder if the wife would like a 5.0 swapped 'vert...

A built AOD is pretty decent behind a modded 5.0 in a light car like these.

Chris, the ducktail on your car is fantastic. Is that something you created?

dyintorace wrote: Chris, the ducktail on your car is fantastic. Is that something you created?

+1. I love the Viper stripes too. I'm a long way from doing bodywork to my FC, but you're giving me ideas now...

why no love for the FD?

I am no RX guy, but from what i hear, they are the RX to own... get a Turbo with a blown motor (common I hear) and drop in the 302, or even the LS...should fit...right?

maroon92 wrote: why no love for the FD? I am no RX guy, but from what i hear, they are the RX to own... get a Turbo with a blown motor (common I hear) and drop in the 302, or even the LS...should fit...right?

The problem is, even FDs with blown motors are much more expensive than SA/FBs or FCs. If I had the scratch, I'd buy an FD in a heartbeat.. but I don't and I don't think the OP does, either.

so, okay, why the ford 5.0?

what does it do over a chevy 5.7?

I've got a 385 4bolt main in the corner of my garage, a 700r4, and an SA. Last time I brought it up everybody on here told me to keep the 12a. wth?!

I've seen it done with SBC's before, but the swap kits for a 5.0 are cheaper by a margin and require less fabrication. If you've got the talent and/or the budget, a Chebby motor might make more sense.

As long as Greg isn't listening, I'll say that spinning triangle motors are the devil's work and should be converted to boat anchors, so start your swap today!

well I scored a swap kit off craigslist for $150 so that's out. fabrication? I've got a mig welder and a cutoff wheel. Technically a sawzall too, if my dad ever gives it back. what are we talkin?

SBC in a SA/FB requires firewall surgery and possibly some other cutting/smashing in the strut towers and crossmember. The SBF literally just falls in, even fitting under the stock hood. The Ford sits lower then the Chevy too making for better handling.

Now in an FC it's a toss-up. Both are easily swapable, and even under the stock hood. The problem is an LS1 falls right in (FD's too) and makes it a supercar.

There's plenty of love for FD's, problem is no matter the price for any SA/FB/FC part you have to add at least one zero on the end for FD. They take cubic dollars to buy, build, and maintain. They are like owning a supercar!

For the ultimate in sleeperness and power-to-weight though, an LS1 supposedly falls right into an FB...

P71 wrote: For the ultimate in sleeperness and power-to-weight though, an LS1 supposedly falls right into an FB...

Now that would be truly Evil!

P71 wrote: SBC in a SA/FB requires firewall surgery and possibly some other cutting/smashing in the strut towers and crossmember.

that contradicts granny's site. all they mention is getting a smaller diameter distributor to keep away from the hood latch and a low profile intake manifold to clear a stock hood(I also have a tpi manifold laying around).

maroon92 wrote: why no love for the FD?

An RX7 guru I know told me that the engineers at Mazda tried to add a little too much lightness to the third gen. He's seen them tweaked so bad that they ripped the carpet. Expensive too.

OK I'm pretty much sold on the FB at this point. Cheap, light, and "drop in" just gets me firing on all cylinders. Pun INTENDED.

I do love my EFI...

It's just too bad a 5.8 MPFI won't match my goals of using a stock hood. Feel free to prove me wrong.

Thanks again for the thoughtful discussion.

Tom Heath wrote: I've seen it done with SBC's before, but the swap kits for a 5.0 are cheaper by a margin and require less fabrication. If you've got the talent and/or the budget, a Chebby motor might make more sense. As long as Greg isn't listening, I'll say that spinning triangle motors are the devil's work and should be converted to boat anchors, so start your swap today!

Right a boat anchor. This is the wrong board to post it but I can't recall any real high HP miata motors running around..... but we are more about handling anyhow. None the less I am 100% for motor swaps especially when the car was heading for a junkyard anyhow. I love rotaries but it is hard to beat the sound and torque of a V8.

As for the LSX swap into an FB. There have been plenty of SBC swaps but I believe the LSX has a whole lot of issues with oil pan clearance and has only been done a handful of times. There also might have been some steering clearance issues as well. The LSX into a FC or FD is well documented however.

Check out this craigslist post for a good start to a challenge LS1 FC.

http://daytona.craigslist.org/cto/897405183.html

No firewall surgery installing the SBF just two points on the firewall need some very minor clearancing, all i needed was a 2lb brass hammer and a couple of good swings, seriously

dyintorace wrote: Chris, the ducktail on your car is fantastic. Is that something you created?

Late '70s Camaro 3 piece unit trimmed to fit and molded in. Had to also add a section to the trailing edge of the rear hatch and mold that in to make it work.

And the stripes were done in '94, patterned after the Cobra Daytona, a couple years before the Viper GTS came out with those stripes on it. It also matched the paint job on my first autocross car back in '80...

Clarifications...

On SBC into SA/FC, I've never seen one that didn't need firewall surgery. They all also had hood pins as the OEM latch was gone, and had huge cowl scoops to clear the engine as it sat way up high. Both of the HEI and the large cap one I saw had notches cut in the firewall (you could see the dizzy through the cowl vent, not so good in the rain). Even the small early point-style distributor one had major firewall dent surgery and the old school straight-up plug wires. Now maybe different kits have come out in the last few years, but my understanding is it is still a lot easier to go SBF.

On the LSx FB. I've seen exactly one, and he used an FC front suspension setup and a 5-lug Ford 8.8 rear (narrowed of course). The LS1 sat low and back like the SBF and cleared the stock hood (f-body accessories).

That craigslist car is sold

To me that looks like a stock hood with the support cut out, and a stock latch.

I seriously don't mean to be argumentative about this, but the first paragraph on the page is;

BASIC KITS...Just what you need to get your V-8 engine & transmission into place. Easy bolt-in installation. No cutting or welding required. Just choose one below that fits your requirements...

Just saying what I saw. There have probably been improvements since then, but I haven't seen any of those in person.

In fact, the only non-SBF V8-swapped FB's I've seen in the last 5 years are the LS1 project and a Dodge 318

Here is FB starter project if anyone is interested. Not mine.

http://tampa.craigslist.org/pnl/pts/905850477.html

dyintorace wrote: Here is FB starter project if anyone is interested. Not mine. http://tampa.craigslist.org/pnl/pts/905850477.html

Seeing that may cause me to change my Pro-FC stance!

OK so to reiterate, A 5.8 SBF will not fit???
I have seen carb'd 351Windsor/Cleveland, but no EFI.

I could care less about GM... I like my distributors in the FRONT.

I've never heard of a 351 in one. They have a taller deck and are wider, not to mention taller. Definitely needs a hood scoop to clear the carn or EFI. (Scoop needed for 5.0 EFI too) I don't see why it wouldn't fit though?