Swap question
#1
Swap question
I am doing a 2.8l to 4.8 Swap on an 87 firebird. My budget is shoestring but I am decent at making things work and or fabricatong what I need.
I have picked up a 700r4 k case from a 5.7l 88 blazer but it didnt come with a torque converter. Now I still have the 60 degree 700r4 from the 2.8l and was wondering if I could swap the input shaft on the k-case with the 60 degree or if it would burn up too quickly/ be too short?
The car has never seen winter (I live in the salt belt of ontario) so it wouldn't be more than a summer fun car for the time being. Eventually it will be upped to a real drag car with a proper built 4l80 or stick shift. But to get it back on the raod, this is what I have to work with. I have already called around and cant find a decent one to fit the budget atm. And I am not afraid to take the tranny apart and swap things over. Also the k-case was rebuilt recently.
I have picked up a 700r4 k case from a 5.7l 88 blazer but it didnt come with a torque converter. Now I still have the 60 degree 700r4 from the 2.8l and was wondering if I could swap the input shaft on the k-case with the 60 degree or if it would burn up too quickly/ be too short?
The car has never seen winter (I live in the salt belt of ontario) so it wouldn't be more than a summer fun car for the time being. Eventually it will be upped to a real drag car with a proper built 4l80 or stick shift. But to get it back on the raod, this is what I have to work with. I have already called around and cant find a decent one to fit the budget atm. And I am not afraid to take the tranny apart and swap things over. Also the k-case was rebuilt recently.
#2
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: Swap question
By 4.8 I assume you mean LS-type engine. What did it come out of?
Was this a 2 wheel drive Blazer? I hope so. If not, sell/trade it for a 2wd TH700.
I'm not totally familiar with the V6 TH700, but the torque converter may fit your V8 transmission. But, if your engine really is a 4.8 LS, you'll need an adapter on the crankshaft, anyway.
Was this a 2 wheel drive Blazer? I hope so. If not, sell/trade it for a 2wd TH700.
I'm not totally familiar with the V6 TH700, but the torque converter may fit your V8 transmission. But, if your engine really is a 4.8 LS, you'll need an adapter on the crankshaft, anyway.
#3
Re: Swap question
By 4.8 I assume you mean LS-type engine. What did it come out of?
Was this a 2 wheel drive Blazer? I hope so. If not, sell/trade it for a 2wd TH700.
I'm not totally familiar with the V6 TH700, but the torque converter may fit your V8 transmission. But, if your engine really is a 4.8 LS, you'll need an adapter on the crankshaft, anyway.
Was this a 2 wheel drive Blazer? I hope so. If not, sell/trade it for a 2wd TH700.
I'm not totally familiar with the V6 TH700, but the torque converter may fit your V8 transmission. But, if your engine really is a 4.8 LS, you'll need an adapter on the crankshaft, anyway.
So I swapped out the output shaft from the 60 degree that was 2wd to the 90 which was 4x4. They are both 30 spline. I kept all the clutch plates and steels from the 4x4 as they were still new. I used the Sunshell from the 4x4 too as well as the rest of the internals. When I got to the input shaft and drum, I used the 60 degree just to test fit. I checked the converter to make sure it would slide on both pumps and it did.
So I buttoned it up and tested the length to the end of the housing for bolts and the center to see if it had the distance for the 4.8l (yes from a truck or conversion van. PO didnt remember was it was pulled from) The clearance for the bolts is dead on with only a 1/16 to 1/8 inch of play from the flex plate. I will have to make an adaptor for the center but it actually does slide into the center of the flex plate. So it's just to keep it aligned. I will need to drill some bolt holes.
I noticed that the shape of the flex plates for the 2.8l v6 and the 4.8l ls were both dished which is why I decided to try it. The 2.8l torque converter is also 10 inches across.
I did save the input from the 4x4. If/when I run into the issue of replacing the converter, I will have to take it apart to clean/replace parts anyway and can switch it back then. Will keep posted on how it works out.