1966 6 cylinder to v8 swap

[mudbone64]

First off let me say that I'm new to this forum and am hoping that you guys can give me some pointers. Though I have some experience working on other muscle cars, I have zero experience working on 1960's Chevrolet trucks. So when my dad said he'd bought a 327 engine to replace the in-line six in his 1966 fleetside, I knew I needed to get some information ahead of time as to what I'd need to know and the parts I'd need to have. After bouncing around the internet trying to find a forum to post in I landed here.

This truck has no power steering with the only accessory drive being the alternator so the engine swap should go as easy as a walk in the park, right? What I'd like to know from you guys is what additional parts I need to have on hand when I make the switch. As I said earlier the truck has a 6 cylinder and the three speed tranny was switched some years ago to a turbo-350. After searching around I've noticed that'll probably have to come up with some engine perches for the 327 to sit on but I'd like some confirmation on this.

Any help you guys can lend me is greatly appreciated. Also, what are the popular parts sources? Like I said, I have zero experience working on these trucks so I need all of the help I can get.

Here's a visual:


Thanks in advance,
Gene

[joe231]

do you know which 6 he has?
if it isn't a 292 you can re use the engine perches and I believe the mounts as well. should be pretty straight forward

[LILRED66]

Welcome to the forum from Kansas City. You have a nice truck to work with.

[ed2552]

from Southern MN! Looks like a beauty you have there. Some of the popular parts houses are LMC, Brothers, and there are many more, just look in the vendors section, they will supply you with what you need. It should be a straight forward swap, as these trucks came factory with the 327, so it is definitely possible, should be fairly easy. Good luck, and keep her on the road!

[MikeN]

If it's a 230 or 250-6 with 3-speed manual, the frame mounts, motor mounts, bellhousing, flywheel, clutch, pressure plate, release bearing, and starter will all swap from the 6 over to the V8.

[mudbone64]

Thanks for all of the tips guys. I spoke to my dad earlier today and he believed the 6 cylinder to be a 250 so the transplant should be more painless than most.

I'll try to post a pic when we're done.

Thanks again,
Gene

[MikeN]

I also used my 6-cyl water pump pulley and alternator on my 350...only needed to come up with a crank pulley and alternator brackets. Use the short V8 water pump so you can keep the alternator on the driver's side.

[wsmolloy]

I am new to the forums, I have some questions on swapping my 250 6 cylinder 3spd column, with a 327. I found a mid 70's 327 with a tubo 400 trany. It was previously in a jeep off road 4wd.

What engine mounts will I need?

I assume I will need to swap the tail of the trany to get it back to a 2wd application, What will I need.

Tranny mount, I saw were the post indicate junkyard find and some hole relocation> I saw this universal mount that has slotted holes for adjustments, anyone used something like this before?

https://www.ebay.com/itm/Dirty-Dingo...19.m1438.l2649

Has any one used these universal steering columns from Jegs
http://www.jegs.com/i/JEGS-Performan...70475/10002/-1

Just got the truck from AZ last week, I have not even tried to start the 6 cylinder. (sat for the last 20years without running) I am in south Florida and will make the 250 with tranny available to a good home cheap.

[Captainfab]

The actual engine mounts on the 250 will bolt up to the 327. Or you can get new mounts for a '63-'72 GM truck with a small block. You do not have to move the engine mount brackets that go between the frame and crossmember. You would be better off finding a different trans. To convert a 4wd trans toi a 2wd version, the output shaft needs to be changed. The entire trans must be disassembled to do that. For a trans crossmember all tou need is an auto trans crossmember from a 2wd '63-'87 truck, Suburban or K5 Blazer. The original bellhousing crossmember in your truck must be removed to install an auto trans.

Originally Posted by wsmolloy

I am new to the forums, I have some questions on swapping my 250 6 cylinder 3spd column, with a 327. I found a mid 70's 327 with a tubo 400 trany. It was previously in a jeep off road 4wd.

What engine mounts will I need?

I assume I will need to swap the tail of the trany to get it back to a 2wd application, What will I need.

Tranny mount, I saw were the post indicate junkyard find and some hole relocation> I saw this universal mount that has slotted holes for adjustments, anyone used something like this before?

https://www.ebay.com/itm/Dirty-Dingo...19.m1438.l2649

Has any one used these universal steering columns from Jegs
http://www.jegs.com/i/JEGS-Performan...70475/10002/-1

Just got the truck from AZ last week, I have not even tried to start the 6 cylinder. (sat for the last 20years without running) I am in south Florida and will make the 250 with tranny available to a good home cheap.

[Macdaddy1]

Depending on the age of the motor the alternator might have to go on the passenger side. Some 327 blocks (64-67) I think did not have the predrilled holes in the block for the alternator to be mounted on the same side as your power steering. Also the passenger side block was not predrilled for alternator bracket. The alternator bracket was mounted to the exhaust bolts. Since you are adding power steering you will need to check to see what bracket configuration you can use. Also short water pump pulley only needs 1 pulley groove and should line up with the alternator. The crank pulley will need 3 pulley grooves as the power steering unit will line up with the 3rd pulley. You might have to be a little creative with shims to get the pulleys lined up perfectly.

[Old Truck Man]

If you have the small radiator it will not cool a 327 on a warm day let alone on a hot summer day. You will need a larger V 8 radiator and fan shroud. Also the 6 cyl flywheel is usually the smaller diameter 9 inch clutch. The V8 trucks mostly used a 11 inch clutch. you will need the pivot ball that screws into the block for the clutch Z bar. Use the straight down rams horn manifolds that have the provision to mount the alternator up high and it will clear the power steering.

[Captainfab]

All trucks from '55-'72 and cars '55-'68 originally came with a short water pump. If you stay with a short water pump, you will be able to use all factory components to change over to a small block. And about 99% of those had the alternator mounted on the drivers side. The drivers side rams horn exhaust manifolds have provisions to mount the alternator.

[Bushman66]

I am getting set to convert my 66 C10 over from the 292 to a small block V8 (307 out of a 71 C10...it was free and rebuilt). I have the larger factory 3 row radiator, and the passenger side motor mount perch. The 307 has the pivot ball on the block.

The only pieces I am missing for the V8 are the alternator bracket and the fan. Can these be reused from the 292 on the V8?

[MikeN]

Check out a company called Alan Grove Components if you can't find pulleys and brackets that will work. A tad pricey, but VERY nice quality stuff.

http://www.alangrovecomponents.com/

[Captainfab]

You can use the fan from the 292 but the alternator bracket depends what you are using for exhaust manifolds.

[Bushman66]

Originally Posted by Captainfab

You can use the fan from the 292 but the alternator bracket depends what you are using for exhaust manifolds.

I have the angled Ram's Horns from a 68-72 (I think C10). I was told that this 307 was pulled from a Gen 2 (67-72) C10.

[hairball]

Great looking truck! The V8 radiator is wider than the 6 cylinder one and mounts above the frame rails. You will have to purchase the lower U saddles or fab some up and weld them in. I am not sure if the upper 6 cylinder mount will still work.

[Chevy Fleetside]

Originally Posted by wsmolloy

I am new to the forums, I have some questions on swapping my 250 6 cylinder 3spd column, with a 327. I found a mid 70's 327 with a tubo 400 trany. It was previously in a jeep off road 4wd.

What engine mounts will I need?

I assume I will need to swap the tail of the trany to get it back to a 2wd application, What will I need.

Tranny mount, I saw were the post indicate junkyard find and some hole relocation> I saw this universal mount that has slotted holes for adjustments, anyone used something like this before?

https://www.ebay.com/itm/Dirty-Dingo...19.m1438.l2649

Has any one used these universal steering columns from Jegs
http://www.jegs.com/i/JEGS-Performan...70475/10002/-1

Just got the truck from AZ last week, I have not even tried to start the 6 cylinder. (sat for the last 20years without running) I am in south Florida and will make the 250 with tranny available to a good home cheap.

If you read this thread you will figure out what to do with the engine. As for the tranny. To switch from a 4x4 output shaft to a 2wd output shaft you will have to take the trans apart to swap out the output shafts. A 400 trans take more horsepower to turn then say a 350 trans. If you go that route you might want to put a 700 r4 trans to get the overdrive. If funds are low then maybe you might not want to do that.

[MikeN]

Originally Posted by hairball

Great looking truck! The V8 radiator is wider than the 6 cylinder one and mounts above the frame rails. You will have to purchase the lower U saddles or fab some up and weld them in. I am not sure if the upper 6 cylinder mount will still work.

The upper mount for the wider V8 radiator IS different.