making an FC turbo II trans adapter or bell housing.
 

a little about my project: im starting with a presmog triumph spitfire chassis shooting for 500whp BP in a weekend warrior using mostly miata parts for suspension with an RX7 5 speed and an RX7 lsd rear end.

just picked up my turboII trans today. i have a 1.8 5 speed trans to cannibalize the front portion of the bell housing off of if i go that route. i was thinking about cutting bell housings in half and welding the BP front to the FC rear.
For those who have done this do you know how strong a welded joint mid bell housing would be?
From what ive read it should hold but ive mainly found welded bell housings on auto trannies.

would the adapter plate be a better stronger option?

would anyone happen to have an old worn out RX7 clutch and alignment tool i could buy off them?

Read this thread:
http://clubroadster.net/vb_forum/showthread.php?t=9930

Get that weak as ---- out of here. Why the ---- would you link to crubroadster when he maintains a build thread on mt.net?

https://www.miataturbo.net/showthread.php?t=19010&highlight=mighty+mouse

Edit: I haven't had any coffee yet today. I'll let you let me sodomize your mouth later to make up for me being rude.

MT fanboi are we?? lol Only reason I linked that one is because i'm sub'd to it at CR and it's easier for me to find. :giggle:

ive read through that build several times. i wanted to make a bell housing instead of an adapter plate cause i was thinking about having a mold made and have it casted as one piece. i know this would be expensive but to a few it may be worth it. I need to make at least 2 one for me and one for a friend. at the very least ill make jig. i am also planning on bending 1/4" rod and welding it to make ribbing for strength.

im not on clubroadster.net so its not getting posted there.

Check out projectzerog.com. Even though its a 4g63 centric site, its all about putting them in RWD vehicles, so there have been quite a few custom bellhousings made over the years. Bill Hincher now sells a line of them, but he also has some build threads about how he came up with the designs that might be helpful for what you're trying to do.

There's a 3 rotor FC in the shop where my car is and it's running a Jerico tranny. They did exactly what you'd like to do by using a stock bell housing and pressing the bolt pattern from the tranny to the stock housing. Looks like a stock piece at a glace because it basically is but I know it took them a little while to get it right. The adapter plate is a simple solution, not sure why you just dont roll with it but it's up to you.

im not understanding what youre describing...

here are the pics i have so far.
the 2 trannies side by side and you can see the engine block i have standing on the crank nose in the back ground ath im gonna be using as my jig for now.

Attachment 186012
Attachment 186013

I'll try to take a pic next time I'm up there. I'll probably stop by today sometime.

Why don't you consider this route.

http://www.jegs.com/i/Quick-Time-Bel...ductId=1293712

Here's a pic if the bell housing that I was referring to above. the tranny side was pressed on somehow to the stock bellhousing. you could posibily do this with the miata engine side?
https://mail-attachment.googleuserco...ww-dU&sadssc=1

There was a guy on miata.net that had an FD trans with a welded up hellhousing. I think his name was "big turbo" or something like that, he was from Greece.

I haven't had any issues with my adapter plate, and it's a hell of a lot easier than welding aluminum. If you do get it welded, and it's welded up properly, I don't see why you would have any issues. Just have to make sure it doesn't warp while you weld it, and that it's perfectly straight otherwise you'll never get it bolted up.

600 for an adapter is too much for me. the plate of aluminum is only $60 and i have plenty of time.

the more i go over your build the more im wanting to make the adapter plate instead of the bell housing.

did you have to space the flywheel out to compensate for the plate?
are you running the RX7 slave cylinder with the miata clutch master?

No, the flywheel bolts up like normal. What I did was to mod the clutch fork to make up the 1/2" difference of the adapter plate (there are pics somewhere in my build). I've seen it done where the TOB was modified to work, but I didn't want to modify a wearable part.

As for the clutch master/slave, I'm using the miata stuff- the slave bolted right up to the RX7 bellhousing.

The actual clutch itself is a miata clutch with an RX7 splined center. Clutchnet was the only place I could find that would build one for me. It's held up fine to my power levels.

Which one of those transmissions is cheap??? If I spend money on an adapter plate, it's going to adapt a trans that is easily, and cheaply picked up at the salvage lot.

It would be nice to have a trans that you know you could beat the crap out of it all down long and not worry. I still baby my six speed.

What is the cost to mill something like this? I'm surprised that with all of the talent on this site (design, fabrication, etc) no one can get a reasonably priced adapter plate to the market. Especially when the material cost is $60.

im gonna talk to some local cnc shops to get a price for machining. but most likely im gonna do my own drilling/tapping like mighty mouse did.

That was why I swapped in a TII trans. They can be had for ~200 bucks, was OEM equipment in a heavier turbo car, and there are plenty of high HP guys drifting on them all day long. I have no worries about beating on mine whatsoever- The weakest part of my drivetrain is me.

I cut mine out with a jig saw like a boss. It did take about 3 hours and a lot of beer though.

I put out a feeler a few years back to see if anyone wanted a plate built, but at the time no one wanted one. Remember the plate is only a part of what needs to be done to get the tranny in (and working), which I guess scares some people off.

I like the gearing with this tranny too; downshifting into first is a pretty cool feeling. The revs are a bit high on the highway, but what are you gonna do?

I think for the right price, quite a few people would buy one just to have around.

As "the friend", this is relevant to my interests:D