chevy 4.3 vs 5.3

TubeToy

TubeToy
Location
west jordan
I am looking into putting a 4.3 or a 5.3 vortec into my new buggy.
I need to know the pros and cons on both motors and what year and truck to get one out of ?
 

Tacoma

Et incurventur ante non
Location
far enough away
If those are your options, there is really no argument in favor of the 4.3 except possibly cost. The 5.3 owns the 4.3 in every respect except that.

Search, the pros/cons have been discussed at length here and elsewhere on the web. ;)
 

mesha

By endurance we conquer
Location
A.F.
I have a 4.3 vortec in my buggy and want a 5.3. I was really mad at the 4.3 then got lower gears and now I am not so mad. I will just keep it now.
 

utah340six

Registered User
Location
west jordan Utah
what a ds kev.
the 5.3 weighs a ton more takes up more room.
more gas
more plugs
more heat
.
4.3
close to same power
less weight
less room
less gas
goes faster then you will ever go.
his top speed 20fph feet per hour.
because he cant drive.
just likes to foll over and play dead.
 

TubeToy

TubeToy
Location
west jordan
The cost on both are about the same for the motor and the ECU, and i am still looking into the wiring part of it all.
What years do they run from on the vortecs, Or what years are the best to look for and witch years have the most problems and why, thanks
 
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eatrocks

Registered User
Ah ok The 4.3 is old school based on the 55 to 99 small block. As such is heavy and has a poorer power to weight ratio. The 5.3 in its cheapest form, LM7 block from a 2002 to 2007 truck, is about 295 hp and 315 lbs. In a package that is all of 430lbs. It’s not much bigger than the 4.3, a L33 5.3 is a round 330 lbs. and is pushing 340 hp the 5.3/LSX will respond easy to a new cam and get another 100 hp
 

UNSTUCK

But stuck more often.
is this like what do I do drink beer or not???

No it's more like, "A dana 60 is stronger then a dana 44". :D


If you haven't built the buggy, then engine size doesn't matter.
I don't think you will see much if any MPG difference.
As long as the 4.3 is MPI, wiring is about the same.

Only real concern is height. The 5.3 in stock trim is pretty tall. The pan can interfere with links and such. I believe the 4.3 MPI is much shorter. If you want to spend some extra money, you can make the 5.3 very short with a car oil pan and intake.
 

StubbyBurb

New Member
Internally speaking the 5.3 is far superior to the 4.3. The 5.3 is only about 4" longer than the 4.3. The 5.3 can get as good or better fuel economy than the 4.3. The 4.3's design will tear itself apart due to the way it's balanced, ask me how I know! If you go with a 2007 and up 5.3 they are all aluminum. Another engine to not over look is the 4.8, it's also a very strong motor. Thats my 2 cents......
 
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