Crash tell me everything you know...

Pook · Nov 15, 2008

about 99 4.3 vortec's and 4l60e transmissions.

:redneck:

Pat · Nov 15, 2008

:corn:

*4.3 on the engine stand, about to attempt rebuild and swap*

I'm in for soaking up some knowledge...

Pook · Nov 15, 2008

how big of a pain is it to get it running good in a buggy

stealthrunner1 · Nov 15, 2008

not hard ask money about his that S&N out in....:awesomework: about 10 am rock garden......:;

dirtygoat · Nov 15, 2008

There are after market harnesses for them or you can use the computer from the donor...

A ton of fleet Astro vans being pounded into the dirt on a daily basis by techs in a lot of different fields has to say something...

crash2 · Nov 15, 2008

Good motor with lots of power--and very smooth thru the rmp ranges vs. my rattly tbi motor..

Really not much to tell pook without spacific questions..

Don't ask money mark---he doesn't even know where the spark plugs are :haha:

As for the tranny---well they pull heavy pigs all day long with no troubles...

But I pretty much known them things inside and out...(except the tranny---don't care to know them :redneck: )

Pat · Nov 15, 2008

So are the older 4.3 not as good as the vortec's?

Whats your opinion of the "rattly" feature? Is that the tbi or the non-vortec heads or the non-roller valvetrain?

Mines older but I was thinking of doing a full roller retrofit and running propane

Trying to figure out a good cam and also compression ratio for running propane on the 4.3, but that should prolly go in a whole other thread.

mthompson223 · Nov 15, 2008

Pat said:
Whats your opinion of the "rattly" feature? Is that the tbi or the non-vortec heads or the non-roller valvetrain?

The 4.3L received a balance shaft for the 1992 MY. The 4.3L is a 90* V6 with offset/split journals to help with the vibration problems of a 90* V6. The 90*V6 with offset/split journals helps solve the firing order imbalance that would result if a 90*V6 had a "normal" crankshaft with shared journals on two adjacent cylinders. The pre-1992 4.3Ls had secondary balance issues due to the 90* V6 design that couldn't be solved by any amount of journal offset; so, GM decided to install a balancer shaft in 1992 to help counteract those forces.

crash2 · Nov 15, 2008

mthompson223 said:
The 4.3L received a balance shaft for the 1992 MY. The 4.3L is a 90* V6 with offset/split journals to help with the vibration problems of a 90* V6. The 90*V6 with offset/split journals helps solve the firing order imbalance that would result if a 90*V6 had a "normal" crankshaft with shared journals on two adjacent cylinders. The pre-1992 4.3Ls had secondary balance issues due to the 90* V6 design that couldn't be solved by any amount of journal offset; so, GM decided to install a balancer shaft in 1992 to help counteract those forces.

On the cpi motor yes--the tbi didn't get it till mid 94'....

Pook · Nov 15, 2008

Whats the easiest way to get more grunt out of one?

crash2 · Nov 15, 2008

Pook said:
Whats the easiest way to get more grunt out of one?

I would throw it in and run it--you will be suprised how well those motors perform....

TreeClimber · Nov 15, 2008

Pook said:
Whats the easiest way to get more grunt out of one?

Add two more cylinders. Voila.

sarg · Nov 15, 2008

Pook said:
Whats the easiest way to get more grunt out of one?

ls1 :flipoff:

Pook · Nov 16, 2008

sarg said:
ls1 :flipoff:

Nah, I am going for the no worries if it dies for $500 I can get another one kinda deal...lets me not worry about running out of oil pressure :awesomework:

Money Mark · Nov 16, 2008

:feedtroll:

Turtle Bite · Nov 17, 2008

Pook said:
Nah, I am going for the no worries if it dies for $500 I can get another one kinda deal...lets me not worry about running out of oil pressure :awesomework:

What about a 5.3l, they are $550 at the portland LKQ yard and are 285-315hp from the factory. Another 100 hp for no extra work to put in if you have the drivetrain to take it. I just bought my third 4.3l from them for $280 (02' model, 68k miles, with warranty) and they have been awesome. Hell, they only want ~$900 for a 6.0l.

wentz912 · Nov 17, 2008

The engine is fine and dandy, but ditch the tranny if you can. That thing is a pos, it's the same one the HMMWV uses and it always gives us problems.

Turtle Bite · Nov 19, 2008

wentz912 said:
The engine is fine and dandy, but ditch the tranny if you can. That thing is a pos, it's the same one the HMMWV uses and it always gives us problems.

I thought hummers used th400's and 4l80e's?

Trevor · Nov 19, 2008

dirtygoat said:
There are after market harnesses for them or you can use the computer from the donor...

...

If you use the computer from that 99 donor, you will have to have the VATS flashed out of the computer. 96 and 97 don't have vats, but they moved some of the wires around in the harness plugs after that. In other words, if you use a 99 harness and a 96 -97 computer, you will have to move some pins around at the computer plug ins.

mike d · Nov 19, 2008

Trevor said:
If you use the computer from that 99 donor, you will have to have the VATS flashed out of the computer. 96 and 97 don't have vats, but they moved some of the wires around in the harness plugs after that. In other words, if you use a 99 harness and a 96 -97 computer, you will have to move some pins around at the computer plug ins.

For instance, Injectors 1 & 6 are in a different spots. So if you notice miss fires in those cylinders thats what it is, more than likely.