M715 project underway 305 chevy with 200-4R auto

[jeeper]

I traded a nice 1979 CJ-7 for a fair 1969 M715 with a non running engine. After getting the truck home I pulled the oil pan and found a rod end had separated from the crank. A quick look on the net convinced me an engine swap would be more suited for my intended purposes. I have been bartering for many years and quickly set out to find a donor on Craigslist. I traded an old dirt bike for the 305 which had 70,000 miles on it. The 305 is pretty close to the original horse power and torque ratings of the original engine so I am trying this. It also came with a working 3L80 tranny. Maybe I should have kept that tranny but I was convinced I wanted overdrive so I traded the 3L80 for a working 200-4R. I am in the process of getting this in but have a question about the jack shaft. The output yoke in my 200-4R transmission uses a larger u joint than the input yoke on the NP-200. I have built a custom jack shaft with the larger u joint on the tranny side and the smaller u joint on the transfer case side.

My question is will this be a problem having a shaft with different sized u joints on each end?

I'll add pictures when I figure out how.

[glenn]

I would trade the 200 trans up to a 700, I think it would be less work for you that way. I don't know what your intended usage is but the 715 is alot heavier vehicle than the stuff the 200 trans came in. You could get a new yoke on the end of your jack shaft to match the trans or see if you could get a new yoke on the trans to match the u-joint on your jack shaft.

[jeeper]

[jeeper]

I've read many sites that say the 200 can be just as strong as a 700. It also doesn't have as big a spread in ratio between first and second gear.

My intended purpose is mild trail driving and top down cruising in the summer.

[defbob]

With the 5.88 gear, any trans and engine will survive in the truck. Well except for the Tornado lol. But if you change to a higher gear ration like 4.10 or 4.56, I would definitely get a beefier trans. I have a C4 trans in my truck, haven't put it through the paces yet though

[syzygy]

Good story on how you got your project... always fun to hear. To answer your question...

My question is will this be a problem having a shaft with different sized u joints on each end?

No, it shouldn't be a problem. Obviously the smaller joint will be the weaker link and if one of them breaks under load it would be the smaller one. There are conversion u-joints available also so you don't have to build a custom jackshaft (unless you're changing the length) -- for example I'm using an NV4500 which had a yoke for a spicer 1350 u-joint, so I just got a conversion joint from napa that is 1350 sized going one way and 1310 sized going the other way. (spicer 1310 is used on the stock axles, transfer case, and transmission)

[jeeper]

Good story on how you got your project... always fun to hear. To answer your question...



No, it shouldn't be a problem. Obviously the smaller joint will be the weaker link and if one of them breaks under load it would be the smaller one. There are conversion u-joints available also so you don't have to build a custom jackshaft (unless you're changing the length) -- for example I'm using an NV4500 which had a yoke for a spicer 1350 u-joint, so I just got a conversion joint from napa that is 1350 sized going one way and 1310 sized going the other way. (spicer 1310 is used on the stock axles, transfer case, and transmission)

Thanks for the answer. I didn't think think it would be a problem until my brother suggested it could be. (I was never a good student and he was).

[jeeper]

Does anyone have any pictures of how they made or installed prbuilt motor mounts on a small block chevy conversion? My idea is not working out too well yet.[IMG] Uploaded with ImageShack.us[/IMG]

[tngreenmachine]

A lot of people have used something called a spicer plate ( you can search for it on here). Basically a plate that bolts to the stock mounts... However it looks like yours have been removed. You can find generic mounts for a chevy into anything.

[GMB]

The 200R is barely holds up in sedans.....Why use it in a 6k lb truck?