rebuilding a 4.3

[brokenwrench]

I have two 4.3's on engine stands now for total rebuild. I called the local suppliers (3) to get complete rebuild kits, (gaskets, bearings, forged pistons) the local price was $1068 for the complete kit. Summit Racing was $469. As much as I like to support the local shops that give me great prices and service, for $600 I just cannot be competitive and do that. Anyways, I am going to do videos and stick them on youtube.

[doyoulikeithere]

I have two 4.3's on engine stands now for total rebuild. I called the local suppliers (3) to get complete rebuild kits, (gaskets, bearings, forged pistons) the local price was $1068 for the complete kit. Summit Racing was $469. As much as I like to support the local shops that give me great prices and service, for $600 I just cannot be competitive and do that. Anyways, I am going to do videos and stick them on youtube.

469 includes forged pistons??

Dont forget, you get what you pay for...

[1Gary]

One of my favorite ref sites is:

www.enginebuildermag.com

Click on the tech section and I think a rebuild for a 4.3 is covered there.This is a engine builder industry site that posts are coming from shops that do engine rebuilds for a living.

[brokenwrench]

I have two 4.3's on engine stands now for total rebuild. I called the local suppliers (3) to get complete rebuild kits, (gaskets, bearings, forged pistons) the local price was $1068 for the complete kit. Summit Racing was $469. As much as I like to support the local shops that give me great prices and service, for $600 I just cannot be competitive and do that. Anyways, I am going to do videos and stick them on youtube.

469 includes forged pistons??

Dont forget, you get what you pay for...

summit gives a parts list for all the components, they are all top quality sealed power and federal mogul parts.

yes, $469 includes forged pistons,

[brokenwrench]

One of my favorite ref sites is:

http://www.enginebuildermag.com

Click on the tech section and I think a rebuild for a 4.3 is covered there.This is a engine builder industry site that posts are coming from shops that do engine rebuilds for a living.

that would be what i do for a living

[1Gary]

One of my favorite ref sites is:

http://www.enginebuildermag.com

Click on the tech section and I think a rebuild for a 4.3 is covered there.This is a engine builder industry site that posts are coming from shops that do engine rebuilds for a living.

that would be what i do for a living

Wait a minute.That be the reason I am suggesting it as a trade publication. #-o

[doyoulikeithere]

summit gives a parts list for all the components, they are all top quality sealed power and federal mogul parts. yes, $469 includes forged pistons,

Wow, Thats a great deal, I priced out forged pistons once and they were over a hundred bucks each.
I wonder if they will ship to canada?

[Cobra]

I order from summit they can ship to canada i use USPS from them

[Bubbathegimp]

summit gives a parts list for all the components, they are all top quality sealed power and federal mogul parts. yes, $469 includes forged pistons,

Wow, Thats a great deal, I priced out forged pistons once and they were over a hundred bucks each.
I wonder if they will ship to canada?

A hundred bucks each is ridiculous since the engine isn't called the 3/4 350 for nothing.
From what I have read, not only can you use 350 pistons in it you can also use the same aftermarket etc 4 bolt caps to convert the block to a 4 bolt mains.

[1Gary]

Rods are offset to the bore on a spit crankshaft.So the spacing isn't the same as a 350.

[doyoulikeithere]

Ya, You can tap 4 bolt caps on to the two center mains, but you gotta line bore it too.
I didn't shop around or anything for pistons, I just asked casually once when I was buying something else.
The 350 pistons work. The rods for sure don't interchange because the crank end is bigger on a 4.3.

This tells it pretty well,
http://myfiero.oceanmoon.com/engineidea ... the-34-350
http://myfiero.oceanmoon.com/engineidea ... -chevy-v-6
but its a bit old and had some things wrong, like:
It says there are no carb manifolds for the newest vortec heads - Edelbrock 2114 fits the bill.
It says the best heads to choose are the very earliest 4.3 heads - I would take a set of 96-2002 vortec heads anyday!..

[brokenwrench]

summit gives a parts list for all the components, they are all top quality sealed power and federal mogul parts. yes, $469 includes forged pistons,

Wow, Thats a great deal, I priced out forged pistons once and they were over a hundred bucks each.
I wonder if they will ship to canada?

I am in Canada, shipping and duty cost $90, I have a UPS box on the American side so I just pick stuff up or get friends to pick it up for me, I share it with 3 friends. I live in Niagara.

[brokenwrench]

Ya, You can tap 4 bolt caps on to the two center mains, but you gotta line bore it too.
I didn't shop around or anything for pistons, I just asked casually once when I was buying something else.
The 350 pistons work. The rods for sure don't interchange because the crank end is bigger on a 4.3.

This tells it pretty well,
http://myfiero.oceanmoon.com/engineidea ... the-34-350
http://myfiero.oceanmoon.com/engineidea ... -chevy-v-6
but its a bit old and had some things wrong, like:
It says there are no carb manifolds for the newest vortec heads - Edelbrock 2114 fits the bill.
It says the best heads to choose are the very earliest 4.3 heads - I would take a set of 96-2002 vortec heads anyday!..

4 bolt caps are of very little if any benefit on a mild performance engine, I used to race at a 2 hp per cubic inch level and we used 2 bolt blocks frequently, never broke one.

[doyoulikeithere]

Ya, I wouldn't go to the expense, unless maybe I had a stroker crank and a machine shop.

So can you tell us a bit more about the engines you have on the stands?
What years are the blocks, heads, cams etc. Are you gonna rebuild em both or just one?

I heard the VIN W engine had a lightweight rotating assembly compared to the VIN Z.
If/when i do mine, I hope to use the crank out of my VIN W in an old VIN Z block with late model Vortec heads.

Pix [-X

[brokenwrench]

Ya, I wouldn't go to the expense, unless maybe I had a stroker crank and a machine shop.

So can you tell us a bit more about the engines you have on the stands?
What years are the blocks, heads, cams etc. Are you gonna rebuild em both or just one?

I heard the VIN W engine had a lightweight rotating assembly compared to the VIN Z.
If/when i do mine, I hope to use the crank out of my VIN W in an old VIN Z block with late model Vortec heads.

Pix [-X

I think the secret to rebuilding these engines is not to share parts. These are both full roller motors, roller cams, roller lifters so I think 2005 and later, I really don't pay any attention as we pump them out all the same, much better than stock. there are so many cranks, heads, rods, . I do all these motors with the balance shaft delete, I put on a regular SBC timing chain. I always upgrade the exhaust valve to 1.60 inches, the intake does not flow any better with a bigger valve. I use an older distributor that I buy from NAPA that has vacuum mechanical advance with a few modifications, I always use studs in the heads as leaking head gaskets seems to be the curse of these engine, they are ridiculously expensive. I have cutters to modify the bowls and do a one shot 3 angle valve job and cut the bowls down at 80 degrees, I use undercut swirl polished stainless valves. I do all my own head work so I put phosphorus bronze guides in. these far outlast cast quides. I beam polish the rods and put in ARP rod bolts. I redrill the studs in the heads and put in 3/8 by 3/8 studs. I drill and tap one of the front oil gallery plugs and put in a Holley jet to squirt oil on the timing chain. I use whatever the nicest colour of aftermarket rollers rockers I can get, self aligning. I use an aftermarket sandwich oil adapter and use a high volume high pressure oil pump. I modify a Milodon windage tray and use the factory pan. All our engines go out with hydraulic rubber lines for an oil cooler and we usually mount this before we pull out an engine, no clamps, one piece swaged lines. All of these engines we put 165 degree thermostats in.

Light rods, light cranks, none of this makes any difference in a motor that makes 1 hp per cubic inch and pushes a two ton elephant.

with good head work, a good distributor, 9.5 compresssion and a mild aftermarket cam, these motors can make 265 hp retaining the factory computer and fuel system. the cam is very mild although more aggressive than factory. these engines pass emissions spec and get improved mileage, usually 3 to 4 mpg improved over factory.

there are no secrets, only common sense and a lot of detailing (blue printing), lets see, what else;

we get all the 4.3 motors balanced, this is expensive but we do all the rod balancing before we send them out, this saves a little, I use a SFI approved balancer and flex plate.

we drill and tap all the heads for all possible knock sensor combinations.

i have an in house nerd who does chip modifications, I know little about how this is done.

I cut the exhaust seats to 2 ml, .080 inch. at 45 degrees, 30 degree top cut and 60 degree bowl cut, wide exhaust seat is important on this motor.

these are not racing car motors, if you rebuild one correctly it does not matter which crank or rods you use. HP and reliability will be the same.