I have a '92 S-10 Blazer 4wd with a bad 4.3L (was REALLY overheated, a
couple of times, don't ask) . I have a line on a new one out of an El
Camino of unknown year. What will I need to make it fit right? apparently
the new one is in real good shape (2K miles on a rebuild) but has been
sitting in the backseat of a van for 6 months, anything I should look out
Thanks for the help. I'm an old Army deisel mechanic, pretty good at
changing oil and scrubbing floors but I am hopeless with civilian rigs. Got
a Humvee question? I can help!
GM used the 4.3 in everything rear wheel drive except the Camero. 1987 was
the last year of production for the El Camino, and its sister line, the GMC
Sprint. Engine choices where the 4.3 or the 305 for the last 3 years.
There were 200 '87 models retitled as 1988, left over from the last
production run. the 85-87 models used a throttle body injection 4.3, earlier
models used the 229 Chevy, and the 231 Buick for V-6 engines with 2 bbl
carbs, both listed as 3.8. liter. The 229 is physically the same as the 4.3
as far as motor mounts, tranny bolt pattern, water pump etc. Valve covers
are different, both are 90 degree blocks, and according to eldebrock they
use the same manifold. The catch here would be things like a place to mount
the knock sensor. Most 229's were painted blue, 4.3 were black, 229 valve
covers bolted with four bolts, just like early small blocks, 4.3 two bolts
through the top. 229 were SAE thread, most 4.3 use metric fasteners.
"Good stuff... What is the difference in the 5.3l I have in my 2000
Silverado, and the old 327 Chevy made?"
About the only thing the same is the displacement. Nothing from the early
engines will fit the new ones. And even in the early 327s there were
differences, forged steel vs. cast iron crankshafts, double roller chain and
gears on some and not others, different heads etc. .
But the 327, 302, and 283 bore and stroke combos always seemed the best to
me. They ran , and they stayed together. There was a lot more meat in the
blocks back then too. I've bored 283's .080, .120 over, I wouldn't think
of trying that today, 030 over is probably pushing it.
another maligned engine is the poor 307. This wasn't an engine designed to
go racing with, but it would pull, it was good torque motor, and if they
were driven with that in mind they stayed together as well. The 307 was a
283 bore with a 327 stroke. They put out 300 lb-ft of torque at 2400 rpm.
Not related to the original question but growing up my folks had a 73
Pontiac Safari wagon with the 400 engine. They bought the car new in 73
and sold it 13 years later in 1986. The car was falling apart but that
400 ran like the day she came off of the factory floor. It was replaced
with an 86 Pontiac Grand Prix (year might be wrong) with the Buick 231
V6. That was the biggest piece of crap they ever owned. That car was in
the shop all the time with engine problems. Anyway my point is, if there
is one, that GM did make some great engines. Good luck in your engine
Its funny but the 231 was ether top dog, or a pile of junk depending on who
you talk to.
But the 231 ie Buick 3.8 was the power plant in the Buick Grand National..
to condemn those.
I should have dug deeper on the 5.3, not only is the displacement different,
the bore and stroke are radically different, 327 was 4.00 x 3.25, basically
a short stroke 350, got love short stroke engines, can we say major rpms
(the 302 was 327 with a 3 inch stroke crank, really short stroke). The new
5.3 is 3.779 x 3.622. So there is really no similarity at all between the
engines. What's interesting tho is the 5.3 ie 325 shares the same stroke as
the 364/6.0 Gen III LS2 and LQ4 engines. Which makes one wonder how
boreable the block is. Also the new engines are using long rods, 6.098"
long as opposed to earlier 5.7" . which raises the question, has block
geometry changed: the deck heights higher, or the crank "lowered" in the
Oil Pan-one pc.seal or two pc. you have to use your oil pan-remote oil
filter check to see you can bolt yours up-You can use your intake if not
TBI - anything you take off your 4.3 has to be able to bolt on the new one.
good luck, Wayne
Thanks for the help guys! I plan to see it on Friday if I get the chance.
The contact number I called from the ad rang up a cycle shop and they had to
holler for the guy. He said the mechanic was good, but I will have to check
Thanks again! I'll keep you posted on how it goes!
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