BUILD THREAD You know she's a keeper when...

Doug Chahoy said:

On the 69 wagon. Was it by chance the very rare factory 2 barrel carb version? I believe 69 was the only year they used that engine in full size cars and maybe trucks.

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It was a swap in. It was badged as a 427 on the fenders.

Well, I got about 50% of a donor vehicle hauled home today. I've started tearing the front apart and removing the wiring harness. Unfortunately, this truck had about every power option available to an S-10 so it has wires going absolutely everywhere.

I think I may just swap intake manifolds and go with a carburetor setup and save the fuel injection project for a later date. On the upside, scrap weight will pay about half of the cost back.

I have the wiring in the Bonneville disconnected and the motor/trans is ready to be unbolted before I stopped for the evening.

Now I get to start hunting for a Mercruiser intake manifold.

Got the motor and transmission out of the Bonneville today. I also got the 4.3 out of the S-10 and all of the wiring stripped off of it. It has a cracked valve cover from the wreck, but other than that is solid.

Fun fact, the intake manifold is a two piece unit with an aluminum lower and a plastic upper intake. Where they meet is a flat flange that should allow a flat aluminum plate with a hole for a carburetor mount to be installed. An Edelbrock intake would be nice, but this build is all about low budget.

I will be picking up some motor mounts and installing clamshells on the engine tomorrow.

Opie Knievel said:

So you're going to mount a carburetor onto the Vortec lower intake? I've never seen that done before. Are you gonna make the plate?

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Yeah, it looks fairly simple to do since the flange is flat and the gasket will make a perfect template. The only thing that might be in the way is the tube that sticks up for the EGR tube. That will probably just get cut flush as I will be capping the EGR off anyways.

Pulled the intake and valve covers off of and it was a bit of good news/bad news.

Good news: Roller rockers


Bad news: My plan of making a carb adapter is probably not going to happen. It will technically work, but I underestimated how little clearance there would be between the plate and the ports so there would be a very real chance of a bad fuel imbalance between cylinders. This could be remedied with a 1 inch spacer and some port work on the runners, but the spacer will actually be harder to build than the plate.

My plan was to build the plate from a sheet of 1/2 inch plexiglass (because damn that would look cool), but to make the spacers I would have to cut the same outline two more times and glue/screw them to the plate. I can get a random piece of plexiglass from work, but I would have to butcher half a sheet to pull this off.

I'll just pinch pennies and get a 2 barrel manifold and carb instead of a 4 barrel setup.

So, I got the correct motor mounts for an 86 4.3 Bonneville, but have had no luck locating a set of the cross member side brackets to attach to the frame at a reasonable price. If I cannot locate any, do you think a set of S10 V8 conversion brackets would work to relocate everything to the normal 350 mount position. I am guessing they would work if they were installed with the extension facing forward instead of backwards.

https://www.summitracing.com/parts/add-713123

I would normally just fabricate something myself, but my garage is not wired to use my welder so premade solutions are my best bet for now.

A little forward progress this weekend. I got the factory 86 4.3 Bonneville motor mounts installed on the block. (I had to cut about half an inch off of the top of the mounts on both sides to clear the S-10 exhaust manifolds) I've got the Buick 3.8 mounts off and another forum member is hooking me up with cross member brackets.

I also bought a replacement valve cover from the junkyard to replace one that was broken in the wreck. These are pretty nice looking valve covers, and cleaned up very well with an SOS pad.

A wee bit of progress today. My motor mount brackets arrived today (thanks 81Regal) and I managed to get them installed.

There is a special place in hell reserved for whoever thought it was okay to make the access to those nuts on the backside of the crossmember like they are. Just accessible enough to not justify pulling the front suspension off of the car, but just hard enough to make getting 3 bolts off and 6 bolts back on take 4 freaking hours.