60-66 4.3L Vortec V6 Transplant

[66LSx]

Originally Posted by 66Submarine

Uhh...what are you basing that on? Much more reliable than an inline six with timing gears and seven main bearings, really?

EFI, modern oiling principles, easy starts, readily available parts, safer higher RPM durations (highway cruising)... yea alot more reliable as far as not leaving you on the side of the road.

Being able to run gravel in the oil pan... yes I'd take the I-6.

Daily driving reliably I don't think its even worth arguing about....its 40 years of advancement.

King pins straight axles are more reliable than IFS... but no one uses them anymore....


Yea I think 99.999% of people would feel much more comfortable taking an EFI modern V6 w/ a t5 across country than a 2bl I-6 250.

An elevation change alone could/would require one to stop and make carb adjustments on the side of the road... (potentially stranding if a mis-adjustment is made)

Reliability is a 2 fold measure in my personal opinion. How good it works... and how easy it is to get back on the road.

4.3L parts are in-stock at every parts house in the nation.
250 I-6.... potentially.... could be down for 3-5 days stranded.

[aggie91]

Originally Posted by 66-PMD-GMC

I am currently helping my friend Adrian with a motor swap in his 63 GMC.
Out comes the tired and broken old 814 pound V6.
The cost of rebuilding this overweight mill is not in the budget for my friend so we started searching and found a rebuilt 4.3L 262 CID V6 out of a mid 90's cargo van for $150.
Complete! Flywheel to clutch fan.

I've done some extensive homework on this motor and even with all the negative hype, in reality its a pretty nice unit..
Before I hear all the V6 bashing and "put a 350 in it" talk, it should be said that Adrian, the trucks own wants something unique and the Chevy 350 isn't that... No Small Block Chebby will be going in the little GMC..
Adrian's 63 is going to be a smooth cruiser, go fast isn't in it's future.. super performance just isn't necessary..
This little mill we found is the 215hp roller cam, fuel injected version.
Since fuel injection and electronic engine management isn't in the budget, yet, a marine 4bbl intake has been found and an HEI distributor ordered.
Doing some quick measurements it looks as if the lil 6 will bolt right in like its V8 big brother.
A T5 will be sitting behind the little mill..

So what is this post about?
I am wondering if anyone on the forum has done this 4.3 swap with a 60-66 truck or suburban.
I see tons of potential, budget permitting, for this swap with lots of future mods available.

I found a beautiful 67 C10 with a 4.3 V6 on the forum, its very nice, but my question is, are there more trucks out there that the owner was brave enough to do something different?

If so, where are they?

I say go for it too. I think the 4.3 is a great lille motor. I think this thread has given me a direction for my next version of my '65.

Originally Posted by Clyde65

I say go for it! not ever day you find a running motor for $150!

I had one in an 85 GMC SWB and it pulled 18MPG back then!

Good luck and let us know how it goes, pix please!

Funn that you said you had one...I just picked up a 1985 GMC SWB fleetside that is all original with a 4.3/TH400 combo. I was shocked there was a TH400 in it since most came with the 700r4 trans at the time. But the SPID is still there and sure enough it is factory 3 speed auto trans. Only one available then was the Th400. It has 2.73 rear gears so it should have gotten great highway mileage.

I got the truck to do a LS swap and make a daily driver. Looks like I might just rebuild the 4.3 and use all the brackets and mounts from the '85 to it in the '65.

Keep up updated on what yall do...

[tincan1966]

Not everyone has an efi/ls budget, nor do some feel the need to have one.

Granted the LS motors are good, but everyone is acting the same about them as everyone did in the 70's w/ the 350.

It's AN option, NOT the ONLY option.

I personally do have an efi truck- I run a 1991 TBI 305 works great, it's dependable, it is outdated by efi standards- sure it is, but it's what I wanted-which is the most important part of this whole hobby.

Build what you want, how you want to and basically screw everyone else, if they're not paying for parts or driving it!

ADDED; I give Sharps a bad time a lot about all his tinkering and tuning, but it is his truck to do what he wants. have to sit back, refocus and admittedly admire the determination to get what he wants.
Sorry for the call out there.

I like the idea of a 4.3/T5 combo in one of these trucks and am anxious to see the outcome!

[1963c-10]

Originally Posted by Sharps40

Parts? Avaialblilty? Cripes......I havn't found anything for a chevy I6 that I can't get off the shelf at oreilly/napa/autozoid/advancedretards, etc.

Except intake manifolds....haha

[Clyde65]

Originally Posted by aggie91

I say go for it too. I think the 4.3 is a great lille motor. I think this thread has given me a direction for my next version of my '65.



Funn that you said you had one...I just picked up a 1985 GMC SWB fleetside that is all original with a 4.3/TH400 combo. I was shocked there was a TH400 in it since most came with the 700r4 trans at the time. But the SPID is still there and sure enough it is factory 3 speed auto trans. Only one available then was the Th400. It has 2.73 rear gears so it should have gotten great highway mileage.

I got the truck to do a LS swap and make a daily driver. Looks like I might just rebuild the 4.3 and use all the brackets and mounts from the '85 to it in the '65.

Keep up updated on what yall do...

I would love to find one just like I had... Mine was a SWB, Sierra Classic, fully loaded with the 400, only option not ordered was the v8. I ordered it from the dealer I worked at. BTW, it was 29 Midnight Blue

[66Submarine]

Originally Posted by 66LSx

EFI, modern oiling principles, easy starts, readily available parts, safer higher RPM durations (highway cruising)... yea alot more reliable as far as not leaving you on the side of the road.

Being able to run gravel in the oil pan... yes I'd take the I-6.

Daily driving reliably I don't think its even worth arguing about....its 40 years of advancement.

King pins straight axles are more reliable than IFS... but no one uses them anymore....


Yea I think 99.999% of people would feel much more comfortable taking an EFI modern V6 w/ a t5 across country than a 2bl I-6 250.

An elevation change alone could/would require one to stop and make carb adjustments on the side of the road... (potentially stranding if a mis-adjustment is made)

Reliability is a 2 fold measure in my personal opinion. How good it works... and how easy it is to get back on the road.

4.3L parts are in-stock at every parts house in the nation.
250 I-6.... potentially.... could be down for 3-5 days stranded.

Can't say I agree with any of that. For one thing, it's NOT "40 years of advancement". Like I said, the 4.3 is an SBC modified very slightly to be a v6. The SBC came out in 1955, which was seven years before the 250 series sixes (194-292) came out in 1962. It's actually an earlier design!

Durability at high engine speeds is a total non-issue. The inline sixes come with an extremely mild cam and somewhat poor head flow; that's what makes them not make power up high. The bottom end is every bit as good as an SBC and will take the same abuse, if not more. 2,500-3,000RPM on the highway is nothing.

IFS vs. straight axle is not the same thing, and straight axles still are run under road tractors. And again, 1960-62 HD Chevy trucks actually had IFS before going back to a straight axle.

I drive my carbureted 250 powered '65 anywhere and everywhere. Not a big deal. I don't worry about it, or drive 35MPH, adjust points everytime I get out like some think you need to (actually running an HEI thingy right now, though), grind the starter until the battery dies every time I start it--I just drive like everyone else. No problems here!

Carbs are not that picky, either. Remember that until very recently pretty much everything on the road had a carb. Also, only idle mixture is adjustable without taking the carb apart in most cases, and you are a real bonehead if you get stranded that way, considering you just back the screw out 1-2 turns and you're driving normally again.

The availability of major internal engine components etc. is just silly. If you can't adjust the idle mixture on a carb there's no way in hell you are going to be doing any roadside engine rebuilding!

In fact, if we are going into that, the EFI/computer stuff is much better about leaving you totally stranded. Carbs are very simple and easy to work on with very few basic tools, and the worst you'll probably encounter would be a bad needle and seat, sunk float, or bad accelerator pump, which are all easily replaced on the side of the road--good luck with a screwdriver and a cooked computer! (That's why boats kept the points/carb thing, AFAIK.)

Lest I remind you that the 4.3 has nothing to do with "EFI". That is the thing attached to the 4.3, and some came with carbs. You can add that to other engines as is commonly done, or add a carb--like the OP said he is doing.

Anyway, just thought I needed to point that out/clarify that. I don't normally say this, but most of what you said is just plain wrong. The 4.3 is a great engine, but it in no way is it "40 years of advancement". It's pretty much JAFSB. (There ya' go, Rich. )

[tincan1966]

Originally Posted by 66Submarine

Can't say I agree with any of that. For one thing, it's NOT "40 years of advancement". Like I said, the 4.3 is an SBC modified very slightly to be a v6. The SBC came out in 1955, which was seven years before the 250 series sixes (194-292) came out in 1962. It's actually an earlier design!

Durability at high engine speeds is a total non-issue. The inline sixes come with an extremely mild cam and somewhat poor head flow; that's what makes them not make power up high. The bottom end is every bit as good as an SBC and will take the same abuse, if not more. 2,500-3,000RPM on the highway is nothing.

IFS vs. straight axle is not the same thing, and straight axles still are run under road tractors. And again, 1960-62 HD Chevy trucks actually had IFS before going back to a straight axle.

I drive my carbureted 250 powered '65 anywhere and everywhere. Not a big deal. I don't worry about it, or drive 35MPH, adjust points everytime I get out like some think you need to (actually running an HEI thingy right now, though), grind the starter until the battery dies every time I start it--I just drive like everyone else. No problems here!

Carbs are not that picky, either. Remember that until very recently pretty much everything on the road had a carb. Also, only idle mixture is adjustable without taking the carb apart in most cases, and you are a real bonehead if you get stranded that way, considering you just back the screw out 1-2 turns and you're driving normally again.

The availability of major internal engine components etc. is just silly. If you can't adjust the idle mixture on a carb there's no way in hell you are going to be doing any roadside engine rebuilding!

In fact, if we are going into that, the EFI/computer stuff is much better about leaving you totally stranded. Carbs are very simple and easy to work on with very few basic tools, and the worst you'll probably encounter would be a bad needle and seat, sunk float, or bad accelerator pump, which are all easily replaced on the side of the road--good luck with a screwdriver and a cooked computer! (That's why boats kept the points/carb thing, AFAIK.)

Lest I remind you that the 4.3 has nothing to do with "EFI". That is the thing attached to the 4.3, and some came with carbs. You can add that to other engines as is commonly done, or add a carb--like the OP said he is doing.

Anyway, just thought I needed to point that out/clarify that. I don't normally say this, but most of what you said is just plain wrong. The 4.3 is a great engine, but it in no way is it "40 years of advancement". It's pretty much JAFSB. (There ya' go, Rich. )

I totally agree.
Even tho I like the newer technology and efi, there is absolutely nothing wrong with older carb systems, IF you know how to work on them and what REALISTICALLY can be expected from them performance and economy wise.

And BTW yes I would drive an I6 with a 2bbl across country!

[Shaky]

Originally Posted by tincan1966

And BTW yes I would drive an I6 with a 2bbl across country!

We drove an I6 with a 1bbl to Alaska. Had to do a fuel pump near Edmonton. Otherwise, it chugged along...

[chevycowboy1985]

Would love to see it done thinking about it my self

[cheessee]

Any updates on this?

[bhc41051]

I had a 4.3L V6 in a 2012 pickup, what I remember most was being terrified every time I had to merge onto a freeway, oh and the countless gallons of fuel I dumped in that POS.

[66-PMD-GMC]

The 4.3 I am using is now a marine motor.
It's not stock, has big valve 99 vortec heads.
Keith Black pistons.
A mild roller cam and rockers top off the valve train.
Along with other typical "small block" mods,
This motor should do well...