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I have been reading about the transmissions and adapters the way it souds you can adapt any transmission to the 4bt if so can you use a 700r4 gm to this engine.
The transmission does, but NOT the torque converter! Smaller circle, only 3 bolts on the 700R4/4L60.. Folks have either done an adapter ring or modded torque converter to the TH400 circle.Yes, A 700r4 has the same bolt pattern as a th400.
i think it's 10.75" on the 700r4. I had a ring made for mine. It's worked for almost a thousand miles so far...The TH400 has a 11.5" diameter bolt pattern, 6 lug (for HD apps).
The 700R4 has a 10.5" diameter bolt pattern 3 lug.
You've got to either
1: modify the flywheel/mounting ring
2: modify your TC
I had a custom converter built, see the FAQ.
11.5" & 10.5" - Going by what my transmission guy said, 30 + years of experience. Only other dimension I can find is ~10-5/8" which is very close to what I was quoted.i think it's 10.75" on the 700r4. I had a ring made for mine. It's worked for almost a thousand miles so far...
experience or not, my adapter has a 10.75" diameter on the converter bolt holes and bolts up to my 700r4 converter and has driven me 800+ miles. I just checked my drawing used for the CNC and measured the extra adapter I have sitting here.11.5" & 10.5" - Going by what my transmission guy said, 30 + years of experience. Only other dimension I can find is ~10-5/8" which is very close to what I was quoted.
I don't dispute what you've measured on your setup. My research shows dimensions with 3 different numbers 10.5" 10.625" and 10.75" from various vendors respectively. Depending on where you measure from there could be some discrepancy. (ie center to center or edge to edge).experience or not, my adapter has a 10.75" diameter on the converter bolt holes and bolts up to my 700r4 converter and has driven me 800+ miles. I just checked my drawing used for the CNC and measured the extra adapter I have sitting here.
there are a lot of more subtle changes from year to year and between the 700r4 to 4l60e, but the 4l60e did replace the 700r4 in use. I'm pretty sure there were actually case changes between the pre 87 and the 87 and later model transmissions. Make sure you get one with a 30 spline input, the early ones have 27 spline and are not nearly as strong. I would try and start with a post '87 transmission if you can. If you get one out of a diesel it will have a usable converter and be usable in stock form, but not ideal IMO. if you get one out of a gasser, you will have to change the governer and the torque converter.4L60E is the same trans as 700R4, but electronically controlled.
700R4 - Get one 88 or later, or get whatever one you find updated to that standard. Better pump, internals, etc. Used in a LOT of GM stuff, especially 1/2 and 3/4 ton trucks w/ gas motors up until about 92. (My C2500 has one..)