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1977 C10 250 6cyl to 350 8cyl engine swap

okI have a 1977 C10 chevy truck with a 250 inline 6. I want to swap out to a 350 crate motor. My question is, will the motor mounts work? if not, are the mounts for the 350 bolt on? or do I have to do some cutting/welding? Also, I believe it has a 350TH 3 speed tranny, this truck only has 52K original miles and all the maintenance was kept up to date on the truck so the tranny is not hurt, will I be able to use that tranny with the new motor? will I need a different drive shaft? is the tranny a simple bolt up? Also, I have been around engines for years, but how about wiring the new engine? will I need a complete new wiring harness? or can I use the stock harness and are there hook ups for things?, coil ignition module etc. I'm more experienced on fords that have a seperate ignition module. does the GM have the ignition module in the distributer? Also, will the stock radiator need to be replaced? and will I need to fabricate new mounts for that, or are they available as bolt on?

Reply to
dcdoc45
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Why mess up a good truck? Thoese straight 6 was probably the most hard working and dependable gasoline engines GM made.

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Reply to
GeekBoy

Well, I figured someone would post that exact statement, heheh Well, I have an answer for you, the one piece intake/exhaust manifold is prone to crack. I cannot get the carb/idle/timing adjusted no matter what I do. This truck was fitted with an aftermarket a/c unit when it was bought. and old Clark I believe, well I took all that off but there was a solenoid on the carb that was supposed to idle the truck up when the compressor kicked in. That solenoid does not work and the replacement is no where to be found. I looked into rebuilding the carb myself, but a bud of mine had the exact same truck/engine combo and broke a stud off in the manifold and had a heck of a time with it after that. I want to avoid this whole thing, I might take the old motor and rebuild it with my sons as a learning project but I need this thing to be a daily driver, I want a plain jane crate motor with a mild cam and carb to use to haul wood, camper, boat etc. I'm just not getting that right now.

Reply to
dcdoc45

Motor mount brackets on the cross member have to be moved, the holes are there already. The tranny will bolt to the block, but you need the correct flywheel for a small block, torque converter should be ok.. You will also need a starter. The drive shaft will remain the same as the tranny isn't going to move. The stock harness will work fine, you may have to unwrap a couple connectors to get them in the correct place. The ignition hook ups will connect to the small block distrib, again as the L-6 distrib was on the right side, the harness may need to be unwrapped to get it to the small block distrib which will be center rear. And yes the module is in the distributor. If the radiator is a 2 core it will handle a stock engine, otherwise replace it with a three core. If the rad looks rough, replace it. You will need to find a V-8 fan shroud, or you will have over heating issues. The 6 bang fan clutch will not do the job, get a heavy duty thermo fan clutch, correct one should be about 8-10 inches in diameter, about 2.5 to

3.5 inches thick, heavy finned aluminum, no stamped steel cover on front, and have a bi-metal coiled spring on the front. If the fan is 5 or more blades it will work, if 4 it wont do the job. Don't bother with a flex fan unless you like overheating pulling a load.. If all you did was remove the after market compressor, and everything else is there, you could grab an old A-6 compressor and the correct mounts from any small block vehicle and get the ac working again with minor work ie hoses etc.

Whitelightning

Reply to
Whitelightning

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