I-6 std to V-8 auto Radiator
 

In a 66 what needs to be done? Does the radiator need to be swapped? Is there an adequate transmission cooler available that the radiator does not need to be swapped? If it needs a different rad what brand/model and where to get it? I have a shroud from a 79 but no 79 rad. Would a 79 rad even fit?

Good floor shifter for a TH400? What to do with the cross member? Can it be moved back and/or modified?

Thanks.

Re: I-6 std to V-8 auto Radiator
 

I'm assuming that you are going to run a small block with a short original to 66 water pump. If that is the case I would get a Champion aluminum radiator and run a 66 stock style fan shroud.

Now the question I have is, Do you currently have the taller narrow 230/250 I6 radiator or the larger 292 I6/ v8 radiator. We maybe able to help you more if you post pics of what you currently have.

Re: I-6 std to V-8 auto Radiator
 

No a '79 radiator will not fit. Just get an aftermarket radiator specifically for your truck as well as the fan shroud. Of course this is assuming as 65 GMC said, that you have the short water pump and the engine is in the correct rear location. For a TH400 trans crossmember, all you need is one from a '66-'87 truck with an auto trans.

Re: I-6 std to V-8 auto Radiator
 

Rad is 25 1/2" wide X 22 1/2" high as I recall and sticks up 2 1/2". The picture didn't turn out so well. The water pump is 7" from base to front of flange so I suspect the long one. I wish I would have remembered to get the cross member from the donor truck.

Re: I-6 std to V-8 auto Radiator
 

It sounds as though you have the V8/HD cooling I6 radiator as well as a long water pump.

Re: I-6 std to V-8 auto Radiator
 

OK it looks like I can re-use the rad.

Next question. I am considering just changing the engine and saving the transmission change until after my son learns to drive the gear cruncher. Will the 250 flywheel bolt to the 350? If not I think I have a 350 flywheel. Will the 250 clutch set up work on the 350 flywheel? Anything else I have to be concerned about?

Thanks.

Re: I-6 std to V-8 auto Radiator
 

As long as your 350 is an 1985 and earlier, yes the 250 flywheel will bolt up as well as the clutch.

Re: I-6 std to V-8 auto Radiator
 

You are a wealth of information Captainfab.

The radiator and the 250 engine are out. The radiator is a Harrison and probably original but pretty thin front to back like there is only one row or at most two rows of cores.

I don't think the used clutch would last long with a bigger engine so back to the auto swap. I am hoping I can get the old 4sp manual out by removing its bell housing and dropping it down on a jack. I'll bring my torch and air chisel there tomorrow to try and get the cross member out in one piece.

Re: I-6 std to V-8 auto Radiator
 

Maybe engine first transmission later. I'm not sure how much the beam that is lag bolted to the 2 X 4 roof trusses on 2' centers can carry safely. It did lift the engine and transmission together off the back of the P/U and onto the bench but wrestling it into the engine compartment from up high could be a different story. Also the 1/2 ton chain hoist may be close to its limit with the two on there together.

Re: I-6 std to V-8 auto Radiator
 

I have a nice restored Harrison 3 core factory V8 automatic radiator I'd sell. Correct to 63-66 trucks. $400 shipped in the lower 48

Text 256 486 1988 if interested - was planning to list it tonight on some parts boards but will give you first shot

Re: I-6 std to V-8 auto Radiator
 

Vince I see you are in Alberta CA now so the 400 price won't be accurate for Canada. So $350 + whatever it costs to get it to you via Fedex

Re: I-6 std to V-8 auto Radiator
 

Thanks. I've got a few sources close by if this one can't handle it.

Re: I-6 std to V-8 auto Radiator
 

I've got a question about motor mount brackets. I bought new motor mounts to bolt to the SBC. Can I drop the engine and attached mounts onto the existing frame brackets that the 250 was sitting on?

Re: I-6 std to V-8 auto Radiator
 

Yes the SBC will drop right on the same frame mounts that the 230/250 straight six used.

Re: I-6 std to V-8 auto Radiator
 

Yes, but not with 79 exhaust manifolds on it, as I found out today. I guess I need rams horns? Any other kinds?

I tore the 250 apart and took a ridge reamer to the cylinders. One piston out and one main bearing off shows it to be in not bad shape. Rings and seals and it would be good to go.

Re: I-6 std to V-8 auto Radiator
 

[QUOTE=vince1;8578927]Yes, but not with 79 exhaust manifolds on it, as I found out today. I guess I need rams horns? Any other kinds?

Just Ram Horn manifolds that go straight down, or the aftermarket for some headers.

Re: I-6 std to V-8 auto Radiator
 

Score! I got a pair of ram horn manifolds on Kijiji for $40.

Some times 2 steps forward and 1 back. Sometimes 1 forward and 2 back.

Engine is bolted in and I find that the HEI cap won't clear the firewall. Also the clutch linkage mechanism would need to be reworked. Now I get to move the engine to the forward holes and get rid of the 4sp, what I should have done to start with..

Re: I-6 std to V-8 auto Radiator
 

I have a question on engine position. Where is the best position and if using the back holes what to do with the HEI distributor to make it fit? What are you guys doing to make it work?

After some research I suppose a small cap HEI distributor will work.

Re: I-6 std to V-8 auto Radiator
 

I have never had any clearance issue with a HEI in a small block installed in the original factory location. It is a little close and you have to remove or install the distributor with the cap removed, but it has always worked for me.

Re: I-6 std to V-8 auto Radiator
 

I was just going to post and I agree with this. By taking the hold down plastic ring/cap for the wires off I was able to get the cap on no problem. Maybe I could get that plastic ring back on again too.

Any tips on getting the clutch linkage hooked up? There doesn't seem to be any support for that on the V-8 block like there is on the 6. I was going to remove the frame bracket and do another one that doesn't require support from the engine.

Re: I-6 std to V-8 auto Radiator
 

Hopefully this bell-crank bracket will operate the clutch for a while until time becomes available to put in the auto.

After giving it a drink she started right up and ran for a few seconds.

Exhaust pipes and mufflers still need to go on as well as finishing up a whole lot of odds and ends.

Re: I-6 std to V-8 auto Radiator
 

The bellcrank needs to be supported on both the frame and engine. The I6 engine bracket does not fit a small block. All you need for a small block is a threaded bellstud to screw into the forward boss on the block. The same factory bellcrank will work.

Re: I-6 std to V-8 auto Radiator
 

I looked at some bare block pics online to compare and on mine that lug at the rear frost plug is missing. There is a block heater in that hole so maybe someone ground the lug off for better access. Anyway so far the clutch seems to work just fine with my bracketry just attached at the frame and I don't think there is much stress on it.

Re: I-6 std to V-8 auto Radiator
 

The truck is home now with its original rad and no shroud. So far so good in that it does not overheat. Winter is coming so it'll be good until spring. The only job I may have for it is to redo our deck and take the stuff to the dump.

I've been cleaning and organizing my garage at home and to my surprise my timing light showed up. Now with all that stuff hanging on the front of the engine, how does one even find a place to get a reading? Edit: Yes there is a shot at it from behind the water pump but I wish I would have degree'd the balancer before putting it on.

I'm not sure if the choke on the quadrajet is working. Supposedly before it warms up the secondaries are to stay shut. I'll also have to make a tool to adjust the air screws. Would a piece of squashed brake line work?