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Posted By: 74AzMaxi Machine Shops - December 10th 2017 4:33 pm
There may be a post about this already, but I can not find it. Do you have a favorite machine shop? I am in need of a shop here in Arizona that does good work with decent prices and good customer service. I need to take a block in to get checked over for cracks and any damage, and possibly bored out if it needs it. I will also need to get the cylinder heads rebuilt at a later time as well. I am between Phoenix and Tucson, so I can go in either direction for a good machine shop. Any recommendations would be greatly appreciated. Maybe we can get a list going for every state?
Posted By: JNPerformance Re: Machine Shops - January 06th 2018 1:10 am
What engine is it?
Posted By: jcd74 Re: Machine Shops - January 06th 2018 1:30 am
Don't waste your time rebuilding old heads, unless your are hell bent on keeping your originals you can do better with new one's with no heart ache down the line (cracked heads). You don't have to spring for some race head on a street motor. What motor?
Posted By: Hasan Ben Sobar Re: Machine Shops - January 07th 2018 2:59 am
Machine Works on Stone in Tucson. Best head guy in town. Nothing wrong with rebuilding LA heads. The later 5.2 and 5.9 motors are the ones with head cracking issues.
Posted By: 74AzMaxi Re: Machine Shops - January 29th 2018 5:01 am
Sorry everyone, I forgot to keep a check on this post. My van is a 1974 Dodge Tradesman 200 Maxi Van. According to the vin number decoder the engine is an "E - LA 318-1 V8 2V". I do have a set of dodge heads in my work shop but not sure what they are from, and I also have an engine from my 1980 dodge w150 which is also a 318 2-bbl engine. So hopefully from the 3 sets of heads I should have one set that is good.Thanks for the responses everyone.
Posted By: Hasan Ben Sobar Re: Machine Shops - January 29th 2018 4:01 pm
I forget how MOPAR changes their CR. If they do it with different CC sizes (heads), you'll want to use the heads that give you the optimum CR. Which will be around 8.5-8.75 to 1. Better a tad low than high as you can play games with cam timing to get more power but if it's too high-you're screwed.

EDIT: Very few differences in CC volume.They used piston height to change CR's. So use the best set of heads you have and mill them to get around 8.75 to 9-ish to 1 CR. If you're going to change the bumpstick, you pick it based on final CR numbers.
Posted By: Reed Re: Machine Shops - January 29th 2018 6:37 pm
For the LA series smallblocks, Mopar changed the compresison ratio mostly with combustion chamber size and design, but a little with piston height. In my opinion, the most desireable stock Mopar smallblock heads are the late 80s/early 90s swirl port closed chamber heads (302 casting for 318s, 308 for 360s). These heads have a closed chamber small volume combustion chamber with swirl port design. Dyno tests have shown a 25 hp gain just by bolting on a stock set of these heads. I have a set of the 302 heds I am going to install on the 318 in my 82 Ramcharger.

You can mill the heads or deck the block to increase compression, but too much milling and/or decking requires modification to the intake manifold and valve train. The easier way to increase compression (outside of switching to a head with a smaller combustion chamber) is to use different pistons with a wrist pin farther away from the crown of the piston.

But if all you are wanting to deal with is a head swap, the late 80s/90s swirl port heads are the best LA head design done by Chrysler. As Hasan Ben Sober noted, these heads have a reputation for crackign, so it is best to either buy a rebuilt pair or at least have the ones you want to use checked out. But it is often just as expensive to rebuild a set of heads as it is to buy a new set of rebuilt heads, so unless you are doing custom porting work on a race motor, you should definitely shop around and research the cost of rebuilding what you have vs. buying new.

Good info here: http://www.hotrod.com/articles/mopp-0607-mopar-cylinder-head/
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