early magnums with LA heads?

[reek]

Was rebuilding one of my motors for my D100 project and noticed something funny. anyone know if early magnums came from the factory with LA heads and intake?

I have a 92 318/5.2 magnum (casting number confirms Magnum block) with what seems like LA heads (5 bolt covers) and intake. Still had roller cams and lifters as well as EFI. appears to be an un-molested motor but I could be wrong.

incidentally the motor has almost 200,000 miles and when I ran the bore gauge through each cylinder, they were all in spec! promising for a budget build.

 

[pacofortacos]

What kind of EFI? Kegger intake or ? ?

 

[reek]

What kind of EFI? Kegger intake or ? ?

it's the factory efi. and that's the weird part, no kegger intake. looks just like the one on my 78 360 LA motor.

the early Magnums still had the oiling ports drilled into the block so the LA heads still work but my push rods are hollow and all have oiling holes and as stated, roller cams/lifters. If it weren't for the intake and the valve covers only having 5 bolts, I'd never second guess the motor being an original magnum. if it were tampered with, why would anyone go out of their way to put LA heads and intake on the motor? maybe the infamous cracked magnum head got the motor early in its life?

 

[pacofortacos]

Maybe a very early model that still had the old LA?
Or someone switched it over to the LA but it would have been quite a project going from multiport to standard EFI - I really can't see anyone doing that.

Roller lifters were used from the 80's in the old LA motor so that wouldn't say much there.

Is it possible you actually have a 5.9??? They weren't magnum's yet in 92.

 

[reek]

double post

 

[reek]

First year for 318 magnums was 92. I was thinking a few early trucks might have left the factory with LA parts? Anyway, the block is stamped with magnum block numbers and "318" on the driver side.

I'll probably never figure it out. either way, I'm going 4 barrel so will need a new intake and new heads. Probably use some of the 5.9 magnum heads I have and have to drop some cash on an edelbrock 7577 and a fitech unit.

 

[Fast69Mopar]

Was rebuilding one of my motors for my D100 project and noticed something funny. anyone know if early magnums came from the factory with LA heads and intake?

I have a 92 318/5.2 magnum (casting number confirms Magnum block) with what seems like LA heads (5 bolt covers) and intake. Still had roller cams and lifters as well as EFI. appears to be an un-molested motor but I could be wrong.

incidentally the motor has almost 200,000 miles and when I ran the bore gauge through each cylinder, they were all in spec! promising for a budget build.

What you have there is one of the 318ci roller cam blocks, which is basically a Magnum block with the roller cam. The late 1991 and early 1992 318ci motors were still considered LA motors hence the LA Cylinder heads, 5-bolt rocker covers and the early throttle body injected intake manifold. The Magnum blocks are physically the same as the earlier LA engines, except the oil passage for the shaft mounted rockers is not drilled, because the Magnum engines oil through the push rods. The boss is there if you need to use the old style heads.

 

[pacofortacos]

Your 5.9 magnum heads aren't cracked? They usually crack before the 5.2's did.

My stock 5.9 magnum heads were cracked but that wasn't what caused me to have to replace them - it was the several sunken exhaust valve seats that did it

 

[reek]

Your 5.9 magnum heads aren't cracked? They usually crack before the 5.2's did.

My stock 5.9 magnum heads were cracked but that wasn't what caused me to have to replace them - it was the several sunken exhaust valve seats that did it

my newest 5.9 heads have less than 100,000 miles so maybe that's why there's no cracks? not sure. Kinda glad about this, the 5.2 build is on a very tight budget. Its supposed to go in the truck I was building for my dad. Unfortunately, he broke his back in a recent car accident so don't think he'll be able to use the truck, has a pretty harsh ride. So Now I just need to finish the project. Will probably use the magnum intake off the 5.9 as well and call it a day.

 

[pacofortacos]

Sorry to hear about your dad's accident, hopefully he has a full recovery.

 

[reek]

thanks. he had surgery and atleast is upright. Truck will probably go to the wife, that is until her Chevelle is ready. she's been eyeing the truck ever since I started the thing.

 

[pacofortacos]

If you aren't doing a valve job on the heads, I would at least lap in the valves and make sure the seats are still good - easier to do it before and be sure vs. having to rip them back off to do a valve job.

The physical therapy is going to suck, but it is nec. to get back to as normal as possible.