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Best solution is to spend 70 on a mild steel 1/8" adapter plate from Speedway, then either install it or use it as a pattern for your own plate before returning it, it is marketed as being for adapting a v8-spec TH350 to a 2.8L v6. Don't try to use a v6 transmission behind a V8.
Thanks. That is what I need. I asked for the adapter plate from Speedway for my 1990 v6 to put the 1985 v8 trans. And they told me that their adapter is not what I need
You need to check the input spline count, it will determine what torque converter you should use. Early V8-spec 700s had the same 27-spline input as the later V6 versions, so getting a useful converter is cheap and easy. Even the loosest '85 V8 converter will be too tight for a 2.8/3.1/3.4
The loosest 27-spline is for a 2.2L S-10 from the mid '90s.
The loosest cheap 30-spline is from a late '90s 4.3L S-Blazer. It's rated as a 2075-RPM-stall, but behind a 2.8 it may work more like a 1200-stall.
Doesn't matter whether it's a 350 or a 700; the adapter required is identical.
I know that.. lol
my woundering is why would someone go though all that trouble to put a v8 700r behind a v6? If it's because of the converters there is plenty to choose from from cheep 100 ones to seni custom 350 dollar mid grade "off the shelf" ones.
I swapped to the th350 because of what I use the car for. But a narrow 700r will take anything the v6 gives to it. Crap man I ran many 11 second passes with a narrow 700r and a 3k stall behind it with no issues.
I guess I'm just woundering why... v8 700r swap into a v6 thirdgen?
the V6-spec 700R-4's guts are not the same as V8-spec, and the V6-spec doesn't survive a stock 2.8 in an S-10, so this is the cheapest and easiest upgrade. The alternative is to put V8 guts in the V6 case, but that is neither cheap nor easy.
In the case of the V8-case versions, the ones used behind the 4.3L V6 are not on par with the ones that came bolted to a 305/350.
In the fullsize pickups, the 305 version got the same guts as the 350 version, not much different from the Corvette / IROC-Z B2L version.
IDK, but it may be that the 4.3 truck version and the LO3 car version could have been identical.
Long story short, if I was going to use a 305 version, I'd prefer a C1500 version over a car version.
You need to check the input spline count, it will determine what torque converter you should use. Early V8-spec 700s had the same 27-spline input as the later V6 versions, so getting a useful converter is cheap and easy. Even the loosest '85 V8 converter will be too tight for a 2.8/3.1/3.4
The loosest 27-spline is for a 2.2L S-10 from the mid '90s.
The loosest cheap 30-spline is from a late '90s 4.3L S-Blazer. It's rated as a 2075-RPM-stall, but behind a 2.8 it may work more like a 1200-stall.
early spec v-8's had 27 splines but they also had a pilot on them. the v-6 27 spline converters did not. converters will not interchange.
Originally Posted by cosmick
the V6-spec 700R-4's guts are not the same as V8-spec, and the V6-spec doesn't survive a stock 2.8 in an S-10, so this is the cheapest and easiest upgrade. The alternative is to put V8 guts in the V6 case, but that is neither cheap nor easy.
In the case of the V8-case versions, the ones used behind the 4.3L V6 are not on par with the ones that came bolted to a 305/350.
In the fullsize pickups, the 305 version got the same guts as the 350 version, not much different from the Corvette / IROC-Z B2L version.
IDK, but it may be that the 4.3 truck version and the LO3 car version could have been identical.
Long story short, if I was going to use a 305 version, I'd prefer a C1500 version over a car version.
other than calibration of the valve body and boost valve, there isn't much difference in the v6 and v8 versions on the 700r4. all the hardparts with the exception of the input shaft, the reverse input piston, and the low/reverse piston are the same. nothing difficult about building a v6 700r4 with v8 spec. change the 2 pistons i just mentioned and the backing plates for the forward and 3-4 clutch packs, possibly a shift kit for calibration. get a good quality torque converter and should be fine.
early spec v-8's had 27 splines but they also had a pilot on them. the v-6 27 spline converters did not. converters will not interchange.
So cut the pilot off.
Originally Posted by 87zjeff
other than calibration of the valve body and boost valve, there isn't much difference in the v6 and v8 versions on the 700r4. all the hardparts with the exception of the input shaft, the reverse input piston, and the low/reverse piston are the same. nothing difficult about building a v6 700r4 with v8 spec. change the 2 pistons i just mentioned and the backing plates for the forward and 3-4 clutch packs, possibly a shift kit for calibration. get a good quality torque converter and should be fine.
False. The number of clutches varies, so the height of the drum must also vary. The 2-4 band width also varied, the 1-2 servo varied, the VB calibration varied, and the governor varied.
I've rebuilt a couple of 700R-4s and a couple of 4L60Es, I know why the average enthusiast never attempts it, they are wiser than they know.
False. The number of clutches varies, so the height of the drum must also vary. The 2-4 band width also varied, the 1-2 servo varied, the VB calibration varied, and the governor varied.
I've rebuilt a couple of 700R-4s and a couple of 4L60Es, I know why the average enthusiast never attempts it, they are wiser than they know.
2-4 band only has one width unless you decide to go with the extra wide band. the drums are the same, it is pistons in those drums and backing plates that varied. most replace the servo with the vette one and they are cheap. i mentioned the calibration variation which generally includes governor calibration.
if you cut the pilot off the v-8 input shaft, you also cut off the checkball that helps with lock-up. also, the lock-up sealing ring is in a different location.
the V6-spec 700R-4's guts are not the same as V8-spec, and the V6-spec doesn't survive a stock 2.8 in an S-10, so this is the cheapest and easiest upgrade. The alternative is to put V8 guts in the V6 case, but that is neither cheap nor easy.
In the case of the V8-case versions, the ones used behind the 4.3L V6 are not on par with the ones that came bolted to a 305/350.
In the fullsize pickups, the 305 version got the same guts as the 350 version, not much different from the Corvette / IROC-Z B2L version.
IDK, but it may be that the 4.3 truck version and the LO3 car version could have been identical.
Long story short, if I was going to use a 305 version, I'd prefer a C1500 version over a car version.
Ok. But just so ya know if the tv cable is set properly and if it has the right kind and right amount of fluid and keeping temps decent, a v6 trans will last... trust me. Whoever said or had a stock v6 700r not last behind a stock v6 really messed it up or did something wrong or had like 250k miles on it. I ran multiple completely stock narrow 700rs behind at minimum of 350hp and never did I burn on up. It would probly explode behind high hp before it would burn up.
There isn't too much internally different at least that really hurts performance exspecially if you only have 200 250hp which is nothing for a good 700r. . But I can't remember what all was different.
11-16-2016, 06:42 AM
