4.3 in a 68 truck
 

Question came up in a conversation with a friend. He has a 68 chevy that had a 250 six manual transmission. Engine is gone but he has a complete 4.3 engine out of an 85-86 truck that is in excellent condition.

His question was if he could use that engine in the truck and if anyone had made that swap?

Re: 4.3 in a 68 truck
 

Never done that swap, but I've always been told that the 4.3 is a 350 with the front two cylinders cut off. I would think with small block mounts it would bolt right in. Don't quote me on that, but I believe it is true. I had a 4.3 in an S-10 and it ripped for what it was. It was alot lighter than a '68 though.

Chad

Re: 4.3 in a 68 truck
 

Haven't done it but, I think it's a good idea.
Pretty much a bolt in operation.

Re: 4.3 in a 68 truck
 

i love the little 4.3 good deal of power for a six

Re: 4.3 in a 68 truck
 

I've never driven a vehicle with a 4.3, but I had a neighbor with a Chevy blazer that had one in it. He always talked about how it had all the power he needed.

I'm not sure how much a Blazer weighs but it should be close to what a 68 shortbed would weigh, I think???

Re: 4.3 in a 68 truck
 

Well the block will bolt up to the bell housing. The motor mounts probably gunna have to check on the that because they do sit further back than on a V8. Use V8 motor stands, possibly move those back to fit the 4.3 and redrill the holes.
There are a ton of aftermarket parts for the 4.3 good little motors, If you have it and have the ambition to do it. I'd say go for it. Its worth a shot.
Be sure to take pics and do a write up so we all can see the progress.

Re: 4.3 in a 68 truck
 

Actually, it belongs to a friend... But, if he uses it, I will definitely take notes.

Re: 4.3 in a 68 truck
 

the 4.3 bwllhousing IS the same as small blocks.
Its been done, there's been a few people come on this board running them. They all claim to love them and say they are powerful.
The only 4.3 I have ever driven that I would call powerfull was the CPI vortec... 92 - 95... i may be off on those years, but in that era. They had plenty of power... when they ran right. They were a nightmare though.
The rest of them, I never liked. I've logged 150,000 miles on a 2001 with a 4.3, and I still say the same as I have for many years. They are slow.

Re: 4.3 in a 68 truck
 

i have a 250,000 mile astro with the 4.3, and i towed 2 69 c10s to the house with it and it didnt even grunt. should be fine IN a c10

Re: 4.3 in a 68 truck
 

my grandfather had a 72 gmc with a 4.3 carbed v6 in it that me and dad swapped in 30 years ago, it was ok but not enough torque for the LWB truck. the efi versions have a bit more torque and are fine for average daily use. the good thing about them is yes they are essentially a 350 with 2 cylinders missing and that means all will interchange except the exhaust manifolds, dizzy, and other v6 only applicable parts. my wife had a 89 astro with the 4.3 for 12 years and that thing was tough as nails, and paid for itself many times over, we sold it to a school photographer in 2001 and he still drives the crap out of it with over 250k miles on the odo.

Re: 4.3 in a 68 truck
 

I have thought of doing this myself, but then the sound of that sbc comes to memory and the 4.3 thought fades away, but I say go for it and let us know how the conversion goes together :chevy:

Re: 4.3 in a 68 truck
 

they had 4.3 V6's in 1979?

Re: 4.3 in a 68 truck
 

I had a short wheel base full size 1987 Chevy van with a TBI 4.3, it had enough grunt to hop the front wheels. Dad had a 89 longbed 1500 with the same engine, getting 2nd gear rubber with the auto tranny was a common occurance and Dad's 71. I think it'd be a great engine in one of our trucks!

Re: 4.3 in a 68 truck
 

Some one on the board did one many years ago, but he is no longer on the board and I think he sold the truck. Here is his web site. I am not sure how much remains on it. He did a very nice job on it, and makes me think about doing one sometimes.

http://www.truckwithaheart.com/67chevy.htm

Re: 4.3 in a 68 truck
 

I think he may have meant a 305 GMC V6...

Re: 4.3 in a 68 truck
 

It should bolt right in but it will sit way back in the engine bay if you use the six cylinder mounts(I would bet there would be at least two feet or more between the water pump and the radiator). If you move it up to the v-8 mounts then you will need to make the driveshaft longer but it will sit in the engine bay better.

Re: 4.3 in a 68 truck
 

I think he may have meant a 305 GMC V6??? I don't think they had 4.3's back then.

Re: 4.3 in a 68 truck
 

Oh, oh... I hadn't thought about that part. I guess it's the rear two cylinders that have been bascially cut from the 350 engine. And ,if this is the case, then the forward position would be best. That way he would only have to find a longer driveshaft and rear cross member for the trans.

I'm beginning to wonder if it wouldn't be best to trade the 4.3 for a decent 350...

Re: 4.3 in a 68 truck
 

My grandpa has a 2008 silverado with a 4.3 and it is not enuff to move a full size truck with out ur foot in it at all times, it should work good with some lower gears and no overdrive.

Re: 4.3 in a 68 truck
 

Someone can correct me if I am wrong but I think to make the 350 (5.7) a 4.3 (262 cubes I think) they actually would have the cut the 4 center cylinders in two, then removed the center section of the motor and married up cylinders 3 and 5 and 4 and 6 to make 3 cylinders per bank. Of course they never actually cut an engine block, just cast new ones in this manner to make a 6 banger. They have the same front, rear, and motor mount holes as any sbc, and all the accessories and transmissions from a sbc will fit a 4.3. Of course it is smaller in overall length front to back, so if mounted in place of a sbc, the motor mount towers will have to move rearward to align with the 4.3 (look at any full size 88-98 chevy with a 4.3... you will immediately notice the huge, long, fan shrouds on these trucks). 1/2 ton work trucks came standard with the 4.3, they are decent little engines as long as you don't work them to hard...they are prone to developing rod knocks if over worked. Just my .02 worth.:chevy:

Re: 4.3 in a 68 truck
 

:flagw::chevy:Great little motors!I have put over 300,000 miles on two different s-10 trucks with that motor:flagw::chevy:

Re: 4.3 in a 68 truck
 

The 4.3 is the same distance from bellhousing mount to the motor mounts as a smallblock, bigblock and even a 250 straight six. It will bolt right in just if you use the six cylinder towers it will sit way back in the engine bay. I had one in a 87 c10 with 3.08 gears and a 4 speed plenty of power here in the flat country for anything I want to pull (up to about 6000lbs).