Alright, so here's my thinking.

I really want a 6 speed, this much is certain.

Now, there are several cars out there with 6 speeds... Camaro's... Firebirds... Corvettes.

And then there is the Nissan 350Z. According to car-part.com, I can get a 350Z tranny for about $1000.

Now, other than a 350Z/G35 engine, what else will bolt up to it? I'm thinking maybe a 300Z twin turbo motor? That would be pretty awesome... A 300Z TT with a 6 speed in my 'vert...

On the flip side, does anyone know exactly which engines will bolt up to the T-56? Specifically, will any V-6s bolt up to it, or is it only the 5.7 V-8s?

Again, I definitely want a 6 speed, but other than that, I am open to ideas, discussion, or sure, even flaming.

 

As far as GM goes, if it's a RWD vehicle, the trannies will interchange - except for the Buick/Olds/Pontiac engines and the four bangers. The only V6 I know of that will bolt up to a T56 is the 4.3L V6.

GM uses three or four different bellhousings across the board depending on what the engine was originally intended to go in - RWD or FWD.

Stay away from the 'vette tranny. The LS* trannies are in the rear of the car and the LT* trannies are just different enough to cause headaches.

 

The F-body LS1 T56 won't work with an SBC without a bellhousing change. McLeod now makes a new SFI-approved bellhousing that will allow you to use an LS1 T56 (or an LT1 T56 with a special pilot bushing designed for the shorter input shaft).

The LT1 and aftermarket (D&D Performance, etc.) T56s will work with both pre- and post-'86 (2-piece rear main seal vs. 1-piece rear main seal) SBC blocks, both factory and aftermarket, without modification. The only thing that needs to change is the clutch and flywheel, IIRC. There have been several magazine articles on T56 swaps into 1st, 2nd, and 3rd gen. Camaros which include the flywheel and clutch part numbers required. A search through google should turn up something easily.

I'm using a McLeod post-'86 SBC aluminum Street Twin (twin disc) flywheel/clutch with my LT1/T56 because it allowed me to convert to a hydraulic throw-out bearing (LS1 push style) and get rid of the LT1 clutch fork and slave cylinder (pull style) for more exhaust room on the driver's side. The required 1/2" spacer (for the extra depth required for the hydraulic T/O bearing) goes behind the bellhousing, not in front, so clearance isn't affected, and the shifter ends up even more perfectly centered (shown without spacer below).

 

So what about my idea of a 300Z twin turbo motor and tranny? I'm figuring with the ECU, it should be about as straightforward as a V8 swap, yes?

 

Not to be a downer, and if you want to pioneer it, go for it... but, have you ever looked under the hood of a 300ZX TT? It's a hell of a rats nest in there. I would NOT want to try cramming that in an RX7 (or any car for that matter). I'm sure it COULD be done, but it'd be a massive PITA for an engine that has limited price/performance potential. A LS1 will weigh similiar and has documented backing. If you want a Nissan engine, go SR20 or RB2xdett series. You can get manual trannies behind either, and have an easier time fitting them (although both are tall engines). The VQ series in the current Nissans are excellent engines, and should fit well. If you really want to get fancy, you could destroke and go TT on it, similiar to the upcoming GTR35. But then you're spending crazy amounts of money...

 

Double Post

 

So is the 4.3L a direct bolt-on? I figured a 4.3 is a 5.7 minus two cylinders, where a 3.8 or 3.4 is a different beast altogether... It should be fairly easy to find a 4.3L, and I really like the idea of a turbo or supercharged V6... Trying to be a bit different .

 

Yup. The 4.3L is nearly identical (except for missing two cylinders) to the 5.7L. Same bore, stroke, bore spacing, basic head design, etc.

 

Your trying to be very different will cost you an arm and a leg. I would shy away from a V6 conversion unless it was factory turbo'd/supercharged. The Japanese V6's are typically very wide and the straight 6 is very long (plus portly).

Looking at both setups with a T56:
Supercharged V6 $10K+ 425rwhp (the stock rods/pistons suck)
heads/cam V8 $6K 425rwhp

LS1 all aluminum
LT1 iron block/alum heads (+70lbs)

Do an LS1/T56 and never look back. Cam upgrade with good exhaust will yield nearly 400rwhp. A cam is about $325-450.

If you want to do a Buick Grand National (3.8 turbo/intercooled) setup I have 2 complete engines with zero miles freshly rebuilt. ONe is fairly stock and the other can handle 550rwhp+.

With any conversion plan how much the project will cost ahead of time. Don't expect this to cost $1K for a transmission and $2-3K for an engine and that is it. You need custom driveshaft/fuel system, radiator, electrical, motor mounts, trans mounts, exhaust system....

Welcome to the work of re-engineering a car.

-GNX7

 

I know it's not a simple drop in procedure... I am just trying to plan for stuff down the road. For example, I'm sure a 4.3L V-6 with a T56 would be pretty damn decent to drive stock, and then I could always switch it out to a 5.7L or turbo it down the road. What I'm looking to do is set up the infrastructure for later mods.

Doing a GN conversion sounds cool, but I really, really hate automatics and have no desire to own one, ever.

 

So just to be 100% clear, the bellhousing will bolt on directly?

 

I don't know why you'd bother with a non-turbo V6 in the first place. The 4.3 isn't a powerhouse in stock form and it would take a considerable amount of work to make it one.

Mark (gnx7) is right... start with a base engine that makes good power in stock form and responds well to modifications. There's no point in tying one hand behind your back before you even start, and you're not going to save any money. The same level of effort on a V8 would make considerably more power.

 

OK, and an LS1 is the 1999 and up Camaro/Firebird motor, while the LT1 is the 'Vette motor?

I just want to be as clear on this as I can possibly be.

 

LS1 is in the 97 up Vette and 98 up Fbody (you will want an Fbody pull. LT1 is in the 93 - 97 Fbody and the later C4 vettes.

The LT1 is basically a SBC with EFI and reverse flow heads. It is iron block and aluminum heads. LS1 is all aluminum.

 

Thank you very much.

 

Here's a more detailed breakdown which engines were installed in what and when, and how much power they made...

https://www.rx7club.com/showpost.php...2&postcount=14

And more details on the Chevy small block generations...

https://www.rx7club.com/showpost.php...&postcount=425

 

You know jimlab, I've seen some threads where you've been given a bad rap... I think you are BY FAR one of the most helpful people on this forum. You guys have all been really cool, and the amount of new info is astounding. You guys rock.

 

A lot of people give Jim a bad rap just because of his choice and direction with his RX-7.

I've always thought Jim to be an excellent guy who's full of information to share.

 

I have liked Jim since about 1996 when he got in trouble for saying "retard sandwiches" on the "big list".


Ah, those were the days!

 

Mmmmm....retard sandwiches

/Homer Simpson

 

yupyup jim is the man

 

Where's pics of Jim's motor?

 

I borrowed the "you've been eating retard sandwiches again" line from the movie "Beautiful Girls".

Yep. Don't forget the ham sandwich aerodynamics and Twinkie velocity debates...

 

Always love that picture! Now get it in the car Jim . Just giving you a hard time.

$100T2- 95% of your questions can be answered with a little thing called the search button....... FYI.

If you have more V8 related ?'s you should search on the V8RX7 forum on TorqueCentral.com

-Mark

 

I'll give you $12 and a half eaten box of chicken for that engine!