3.9L performance upgrades
#11
i could have sworn that i read somewhere the LA and Magnum blocks had different mounts, but that each was interchangeable within its own set (all LA blocks have same mounts, all magnum blocks have same mounts). in fact i think i read that in the FAQ
#12
The Magnums use the 3 mounting bosses in the middle of the engine. The LA's have the bosses but some have them drilled and threaded, some don't.
#13
Anything more than a V8 throttle body is throwing money down a rathole.
Do watch the LA cams- fuel pump lobe, length of the input, may be other differences
But a cam is not worth the money (you do not have much low end to trade off)
Either
360 swap (engine and trans with wiring harness and computer)
Or
(heresy follows)
a late model Chevy and trans
both much more cost effective.
late V8 Chev may weigh about what your V6 does
Do watch the LA cams- fuel pump lobe, length of the input, may be other differences
But a cam is not worth the money (you do not have much low end to trade off)
Either
360 swap (engine and trans with wiring harness and computer)
Or
(heresy follows)
a late model Chevy and trans
both much more cost effective.
late V8 Chev may weigh about what your V6 does
#14
My Uncle wimped out on the turbo build. He thinks it will take to long to get going.
So I am looking for more options. He still doesn't want to do a V8 conversion even though I have a 5.2 I would give him for the truck.
I guess my only other option is converting the LA block to magnum heads. The build is going to be a high compression Magnum conversion. The stuff I can think of that I need from the Junk Yard is:
magnum heads
intake
TB
timing chain cover
accessory brackets
pulleys
camshaft
engine wiring harness
fuel rails
Manual trans PCM
Magnum tappets
Are the V6 magnum heads prone to cracking like the V8 magnum heads?
Is there anything else I'm missing on my to-get-list?
I know the magnum V8 cranks are a little lighter than the LA cranks, does that apply with the V6 cranks as well?
So I am looking for more options. He still doesn't want to do a V8 conversion even though I have a 5.2 I would give him for the truck.
I guess my only other option is converting the LA block to magnum heads. The build is going to be a high compression Magnum conversion. The stuff I can think of that I need from the Junk Yard is:
magnum heads
intake
TB
timing chain cover
accessory brackets
pulleys
camshaft
engine wiring harness
fuel rails
Manual trans PCM
Magnum tappets
Are the V6 magnum heads prone to cracking like the V8 magnum heads?
Is there anything else I'm missing on my to-get-list?
I know the magnum V8 cranks are a little lighter than the LA cranks, does that apply with the V6 cranks as well?
Last edited by JGC403; 09-01-2012 at 11:42 PM.
#15
Just get the Magnum motor block too, not just the heads. The LA's engine will need oil passage drilling and other modifications to make the Magnum heads work. Also the bolts on heads that hold down the intake are at different angles, so the intakes are not swappable.
Installing a complete Magnum motor with wiring and PCM and all is going to be best.
All in all your best bang for your buck since your swapping everything around is to do a 5.2 or better yet a 5.9 Magnum swap.
Installing a complete Magnum motor with wiring and PCM and all is going to be best.
All in all your best bang for your buck since your swapping everything around is to do a 5.2 or better yet a 5.9 Magnum swap.
#16
I know but he doesn't want to do it.
#17
#18
#19
No matter what I did to my 89 v6, I just couldn't get anywhere near the power I desired. I tried new exhaust from manifolds back, new plugs/wires/distributor, cold air intake, anything that I could do without pulling the motor. Anything more than that cost too much money for it to be worth it in my opinion. Sadly, the LA 3.9 is just not a performance engine. I have no regrets from my 5.2 magnum swap.
Last edited by Mirado; 09-03-2012 at 10:22 AM.