garys 68

iTrader: (1)

Just another thought on transmissions. Anyone ever thought about converting a 944 turbo transaxle to bolt directly to an LS block? They're pretty strong and relatively cheap. They also have the halfshaft outputs on the front of the trans. Just looking at them, a bell housing adapter and Input shaft adapter look to be the only pieces to fab.

Crazier

I did finally get the new clutch fork, the eBay seller I choose because it was close to me was actually out of stock on them, and the back-order took forever, by the time I got it it was nearly back to school time. On top of that I had a family vacation planned so nothing has been done, motor trans and drive shafts remain dissembled and out of the car. Forecast calls for a big chance of rain over the next couple of days but I am hoping to get it all back in this weekend.

I am still having trouble finding replacement shocks as mine have a spring over them, not sure if I NEED them, but the extra pounds of a small block over the corvair's 6 cyl I think they are a good idea.

Crazier

Been out of commission for a while do to finances and distractions.

I am very much considering swapping over to a thm425 with a shorty thm400 tailshaft and the front end off an s10.

The trans and differential I have should be worth more then the set up I want (if I can find the right buyer)

Looks like I have a little rust on the cylinder walls, so it is probably heading for a rebuild, though I may be able to just have it honed and re-ringed, we shall see.

Going with the 425 trans would allow room to move the back wall of the cockpit back and provide some much needed leg room. It would allow for a lot of room in horsepower gains and eliminate some of the tricky mounting I have going on now.

cprmn14

Looks the chevys version of the Lotus Elise, lol cool project man!

garys 68

iTrader: (1)

Before you spend any money, do a search here regarding the th425. I recall some clearancing issues.

Crazier

Hey gary, good to see you are still here.





A lot of the issues are caused by the differential, this is eliminated with the tailshaft and driveshaft set up.

this also give it a far more desirable weight ratio. In addition this will give me rear disk brakes off the s10 and a LOT more options for upgrades to the suspension components. IF I can make this work it is definitely the way to go, and it is your fault anyhow gary, been thinking about it ever since you suggested it.

I am hearing that there is an issue getting the flywheel into the bellhouseing but that this can be rectified with a grinder.

I have not decided to go this route, as I know there will be clearance issues with my frame and the trans. but I think I am going to buy a "core" transmision for $150 and mock it up, see what fits and what doesn't, then if i determine it is feasible I will have it rebuilt.

tonypaul

iTrader: (2)

I have this setup in my garage, I was working on it for my Lambo Diablo Replica. Although its not finished completly I got alot of the leg work done. I had been working on it for about a year (off/on) trying to figure out everything. One day I said 'F" this and purchased a complete 2007 LS4 drivetrain out of a Monte Carlo SS . The th425/ LS was a neat concept, but there is just to much custom stuff it needs.

The bad thing about this design is that is no longer mid-engine its more a rear engine in a normal mount. There is alot (whole lot) of weight behind the rearwheels making for really bad handling. Trust me, I did this 7 or 8 years ago in a street/strip Fiero I built, it was *** HEAVY!
This lastest Venture I was doing was to be installed backwards, with the front of the engine facing the back of the car. This was a much better setup it placed the drivetrain up more towards the center of the car making it a true midengine setup. This ment I had to get a front Diff that runs backwards. After trying a few different setups, the best I found was the H3/Chevy Colorado. I ended up getting one from a Colorado with the 3.42 because the th425 is only a 3 speed. But the diff needs to be installed upside down.

Theres is ALOT to do in this setup, C6 oil pan, custom adapter plates, expensive bearings, custom c/v axles, plus alot more. In the end I just figured out that it too much 1 off items that have to be fabbed. And I decided I dont need a 700hp Diablo thats not going to dependable. I want A/C, to be able to take road trips,ect, so the LS4 was a much better choice for me.
I will post a pic of the setup later today....

Crazier

I am very interested in seeing your pictures.

I ws planning the mid engine style with the truck diff.

tonypaul

iTrader: (2)

Here is some what of what I was doing. 1st challange is to mate the BOP bolt pattern of the th425 to the LS motor. Not imposible, the 2 lower bolt holes line up as well as the guide pins. There are adapters that fit betwen the trans/engine but they are for the traditional th350/th425 BOP and not the th425 which is a little different. They can be modded to work, but there is a better way to go I think, but if you decide to go this route I will show you. And yes there alot of other issues you have to deal with on the flex plate,ect.

One of the biggest problems is the rotation of the th425 with out the factory diff. The trans goes backwards at the output shaft, its I think 33 spline female. Getting a diff, like a IFS out of most 4x4 trucks will not work as the rottation of the gears is wrong. If you flip the diff to get the correct rotation the longer side of the output axle will be on the wrong side.

The only ones I found the fit good are out of 4x4 Kia Sorento but the gear ratio is crazy low like 4.77 or something, too much for the 3 speed th425.
The H3 and the Colorado both fit good being flipped but again- gear ratios.
I got a 3.42 diff from a Colorado, but they are rare, most are 3.73 which still is prettly low for the highway. The only other diff that might work is from a Porsche SUV, cant remember which one. It had 3.3? something but I never got one to try out. I have front diffs from a Chevy 3500, S10 Blazer, Ford Explorer, Kia Sorento, and few others none work the way I wanted.

Then you have the adapter plate for the trans to the rear diff, you need to have a bearing pressed into it perfectly for whatever shaft you use to keep it from moving around. Finding the perfect bearing that fits your outputshaft and your output housing isnt easy. Inmy case custom machining was involed and the bearing itself was $88.00.....

There there is the suspension, axles,ect,ect.... All custom, all expensive....

Believe me Im not trying to discourage you from this, I really wanted 600-700 hp, a automatic trans mounted longitual. I have spent years messing with th425 transmissions, I could build one blind folded. But in the end, I did some soul searching and figured out that what I want and need is two different things. For this car, I really dont need 700 hp, I need something fun to drive with A/C that I can take on road trips, fun runs, Bull runs, ect.

The LS4 Im swapping in, will be about 150 lbs lighter than the th425, will have A/C, Paddle Shift auto trans, great gas mileage, and around 300hp stock. There are tons of aftermarket should I decide to put some more power in it down the road. AND it will be done in 3 more weeks, unlike the th425/LS that would have taken atleast another year...

Crazier

I was under the influence that the shorty 400 tailshaft would bolt up and that the s10 front end would do the job. if those things are not true then the project becomes far to big of a headache.

I just do not want to have to baby it every time i start from a standing stop. and i wanted room to add a turbo or two later on down the road.

tonypaul

iTrader: (2)

No the th400 tailshaft housing will not just bolt up with out some kind of adapter. Then you gotta get some kind of output shaft, its gotta be 33 spline male the same lenght as the housing. If you see one of my pics it shows the NP205 output housing and the th425 diff's output flange with a u-joint flange mounted to it. The u-joint flange has to mounted perfectly centered to the output flange. The first one I did was off not even 1/16th of inch and it wouldnt work....

If I was you- I would try to find a whole front clip from a Malibu,Monte Carlo,ect that has the LS4 in it. I think that would give you the most bang for your buck, you would have everything- brakes, suspension,motor,trans,ect. You would just have to have the harness reworked and the ecu reflashed. I know soomeone who could it pretty cheap, or just go Microsquirt and a aftermarket trans-controller like me.

You could just cut off the rear frame section on your frame and fab up the whole front suspension and motor/trans ect to your frame. Just take out the steering and add some tierods or adjustable suspension bars with hiem joints. There is a pic of a guy building a kit car somewhere (I will try to find it), that what he did but with a Cadillac Northstar.

He just took the whole front cradle and fabbed it up to his frame came out pretty nice and far cheaper than trying to piece together a whole seperate engine /trans/axles/suspension....

BTW-Sent you a PM....

tonypaul

iTrader: (2)

Basic concept I was suggesting-

Crazier

This project has been shelved (or tarped as it were) for a while for a number of reasons, including some deep soul searching by me about what I want out of it, both now and in the future.

I came to the conclusion that a Corvair Transaxle would be "ok" for now, but that I would never be satisfied with it and its 300 FPT limit.

The focus has been on thinking about and finding a way to pay for a C5 or C6 corvette rear end graft.

It has been a struggle to track down all the info I needed, and my interest has come and gone a few times, now I have a basic plan and am waiting for funds.

The C5 transaxle combo is only about 3 inches longer then what I have (I am still waiting on measurements for all the transmissions that came in corvettes, some may be shorter). so I have to decide the best way to proceed. (and come up with the cash)

I would like to graft a chunk of C5 frame right into my frame and elongate the body by two inches, but that requires skills I do not posses. Short of that I can take 2 inches out of the passenger compartment, but the space in there is already minimal.

I would also need to widen the body or add fender flares of some sort.

I have not yet tracked down an official "rotor to rotor" measurement on the c5/c6 set up, only track widths and body widths.

Track width on the corvair 56 and on the vette 62 body widths are practically the same at 73 and 73.6.

The track width is showing only about 3 inches per side difference, but I would guess the rotor to rotor measurement would tell me more.

The project as currently conceived would graft in the c5 frame chunk and use the corvette suspension, cradle, diff, brakes and pretty much everything attached below the frame.

There is a company that makes a powerglide adapter for the C5 diff, and the powerglide would fit, but I don't think it would be as much fun and it would not be optimal at the road course.

So if anyone is still reading I would appreciate any thoughts, or if you happen to own a c5 or c6 corvette, some measurements and or pictures would also be greatly appreciated.

Crazier

4l60e LS1/LS2-style (1998-later) 23 19/3 from engine mounting surface to tailshaft mounting surface

"C5-glyde" When assembled it measures 22.562" from bell housing face to axle center and 30 overall. 20 9/16 from engine mounting surface to tailshaft mounting surface

http://www.rsgear.com/TCase/TREMEC/T56Corvette.pdf

If I did my math right that PDF says that a t56 is 25.5 long 3 inches longer then the powerglide, for an axle to engine mounting surface of 25.6, roughly 5 inches longer then the corvair set up. That would likely require both a fram and body stretch AND cutting into the cockpit area.

Crazier

http://www.fiberfab.us/1002205C.html need to find this guy

kpeterson

Good to see this one back to the top again. Very cool (and high effort) project.

1bigoldman

Check with Novanutcase on Steve's Nova Site. He is using a C5 T56/transaxel in his 2nd Gen Nova. He is building a custom tubular frame to support it.

http://www.stevesnovasite.com/forums...ad.php?t=78088

Crazier

http://www.fiberfab.us/1002205C.html
http://www.avenger-valkyrie.org/feat...oung/index.htm

can anyone identify the trans used in this project from the pictures?
This guy was an artist of the highest order... but I cant find any aditional info online.

garys 68

iTrader: (1)

Did you ever look into the 944 trans. They're cheap and available and configured like the Audi trans.
Am I missing something obvious?

The Dark Side of Wil

Same here... is there something about a more conventional transaxle that you don't want to use?