Replacing 78 231 3.8L with later 252 4.1L V6 questions

[Boydness]

The current '78 231 motor (2 barrel carb) in the vehicle has a dead cylinder (and mated to a TH200, I believe).
I have a 252 (Q-Jet) with a TH350 from a Grand Prix, although I am unsure of the exact year.
Not exactly sure how to identify the motor, but the transmission has the sticker: 9KE 0161 8641764 BUICK 0792028

Any recommendations on how to determine what I have and how best to proceed further?

 

[olds307 and 403]

The biggest issue will be the Quadrajet carb on the 4.1. It is a CCC carb and requires a computer. The distributor off your 3.8 will work with the 4.1. You need a different carb or the computer and harness from the 4.1.

 

[Boydness]

The biggest issue will be the Quadrajet carb on the 4.1. It is a CCC carb and requires a computer. The distributor off your 3.8 will work with the 4.1. You need a different carb or the computer and harness from the 4.1.

What are the options with replacing the CCC carb? Is there a year range of OEM carbs that will replace the CCC carb?
If I go with an aftermarket carb should I replace the intake with an aftermarket as well?

 

[olds307 and 403]

Unless you swap the cam, the intake probably isn't worth it. A new timing set is a good idea. You could find a late 70's carb with the same routing but would need rejetted. A Holley 390 with adapter or the new Street Demon 625 cfm would be a good start. The Street Demon won't need an adapter but would probably need tuned as well. A Canadian carb off a 4.1 would work, we didn't get the CCC until 1986 on most cars. Does the carb have a blue plastic connection on top and a tps hook up? I read 80 was the first year for the 4.1. I believe not all 80 models had the CCC.

 

[Clone TIE Pilot]

Uh-oh, that is going to be a problem. Buick changed the intake manifold pattern on their V6s in 79. So a 1979 or newer intake won't bolt on to a 78 or older Buick V6 heads. Looks like the only way to use a 4bbl will require swapping to newer heads too. Odd ball years really suck. If you had a 1979 V6, the 4bbl intake would bolt right up.

 

[Boydness]

Unless you swap the cam, the intake probably isn't worth it. A new timing set is a good idea. You could find a late 70's carb with the same routing but would need rejetted. A Holley 390 with adapter or the new Street Demon 625 cfm would be a good start. The Street Demon won't need an adapter but would probably need tuned as well. A Canadian carb off a 4.1 would work, we didn't get the CCC until 1986 on most cars. Does the carb have a blue plastic connection on top and a tps hook up? I read 80 was the first year for the 4.1. I believe not all 80 models had the CCC.

Uh-oh, that is going to be a problem. Buick changed the intake manifold pattern on their V6s in 79. So a 1979 or newer intake won't bolt on to a 78 or older Buick V6 heads. Looks like the only way to use a 4bbl will require swapping to newer heads too. Odd ball years really suck. If you had a 1979 V6, the 4bbl intake would bolt right up.

That's not good news at all. Is there not a method to continue using the 252's current intake with a non-CCC carb?

 

[Clone TIE Pilot]

Any Qjet would bolt on to that intake. Just that a 4.1 intake won't bolt to a 1978 or older V6.

 

[Boydness]

Unless you swap the cam, the intake probably isn't worth it. A new timing set is a good idea. You could find a late 70's carb with the same routing but would need rejetted. A Holley 390 with adapter or the new Street Demon 625 cfm would be a good start. The Street Demon won't need an adapter but would probably need tuned as well. A Canadian carb off a 4.1 would work, we didn't get the CCC until 1986 on most cars. Does the carb have a blue plastic connection on top and a tps hook up? I read 80 was the first year for the 4.1. I believe not all 80 models had the CCC.

This is the carb:
Front

Rear

Choke

 

[Boydness]

Any Qjet would bolt on to that intake. Just that a 4.1 intake won't bolt to a 1978 or older V6.

Oh, ok. I wasn't planning on moving the 252 intake to an older block. I am just looking to use the 252 in the wagon, which has the '78 wiring.
I use to have the list, maybe from Lars, that had the numbers and configurations of all of the q-jets. Am I looking for any pre-81 v6 4.1L carb?

 

[Boydness]

What about what I found here: http://forums.off-road.com/jeep-short-w ... n-cfm.html

This is from Tim who has a '66 Jeepster Commando w/Buick 252/4.1L V-6

Edelbrock calls their Q-Jet the "Performer Q-Jet", not to be confused with the Edelbrock "Performer", which is a clone of the Carter "AFB". The Edelbrock Performer Q-Jet #1904 runs $435-$450 at Jegs and Summit. This is what I'm running on top of the Edelbrock Performer intake manifold for my 252/4.1L in my Jeepster. The Edelbrock "Performer" and Carter "AFB" run $225 or so. If you want a new carb and won't save up for a Q-Jet, then you might be okay with the Carter # 9504, (elec choke), 9502, (manual choke) or Edelbrock 1404, (manual choke), with or without electric choke kit #1478 along with spring-loaded needle and seats. These carbs are rated for 500 cfm. My tune-up Guru says the Carter AFB's have better quality control over the Edelbrock Performer's. But the Q-Jet will run at nearly any angle. If you go with a Q-Jet on the Performer intake, you'll need a spread-bore to square-bore adapter which runs about $20.