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Head conundrum.. used head vs. new bare casting

Posted: May 3rd, 2008, 9:40 am
by SilverXJ
So.. I bought a used 4.0L 0630 casting head to polish and port with a 3 angle valve job to put on my stroker. However I went to the machine shop to get it magnafluxed, hot tanked and the valve guides checked. I come to find out that they have a brand new 0630 bare casting, still in the Mopar box, in the back just sitting there. They want $200 for it. So, do I get the new 0630 casting and sell the used one?

The old one might need new guides, maybe valves
The new one will need new valves

I already have springs, locks, retainers, etc.

They will both receive a 3 angle valve job, valve spring seats cut, port and polish, etc.

I'm considering going by today before they close and getting it. Probably sell the old used head.

What do you think? Stick with the used one I already have or get the new bare casting?

Re: Head conundrum.. used head vs. new bare casting

Posted: May 3rd, 2008, 5:27 pm
by aaronkeiser
hmm thats a good question. I love new parts but i also like money in my pocket. If it was me id keep the old head if its in good condition and work off of it since you wouldn't have to buy new valves unless they we're burnt or just no good. But you might need to resurface it which is like...what 60-70$(atleast thats what carquest charged me) If you got the new head you'd probably want new valves which cost $. So its new head with new valves or old head with resurfacing. Do new casting usually need resurfacing? It's up to you...do you want to go the extra mile and have a brand new head or are you comfortable with old refurbished stuff?

Re: Head conundrum.. used head vs. new bare casting

Posted: May 3rd, 2008, 5:33 pm
by John
I actually prefer a used heads and blocks that have been thermally cycled repeatedly and then pass testing. Whichever head you go with you might consider carefully checking the condition of the valve guide as compared to spec. dimensions. You find new ones with issues, give a shout if you need those dimensions.
John

Re: Head conundrum.. used head vs. new bare casting

Posted: May 3rd, 2008, 6:00 pm
by SilverXJ
The machine shop is checking the guides for me. I did a preliminary check using a dial indicator positioned on the valve stem near the guide and the highest reading I got was .0035", which seems a bit much to me. I don't have the proper tool to check it 100%. She also showed me a SBC valve and guide and valve which was new and it showed very little play, much less in the used head.

I may end up using both heads. I also have a 95 ZJ w/ a 4.0 in it that has 160,000 miles on it. It will eventually need a new engine. So.. I may hold on to the used head and build that for the ZJ and get the new casting for the XJ. i know new valves will run me a bit. Their prices were 8.48 and 10.94 each. If the valves that are in the used head are still good I could put them in the new casting. I also have a good set of valves, retainers, springs and locks from my 2000 head. The problem with those are that they use the three groove lock, and I don't know of any retainers that will work with the stock lock.. are there any? However I could use those on the ZJ and just go with a stock or mild cam.

It's hard to pass up a brand new casting for a head that is no longer being made.

After I dropped the head off I took my 0331 head and did a practice port and polish.. that will be for a new thread after I eat something.. oh.. does anyone have a pair of crappy valves they would like to sell me?

Re: Head conundrum.. used head vs. new bare casting

Posted: May 6th, 2008, 11:49 am
by 1bolt
IMO if I was you I would forget the idea that a new bare head is something valueable. As John said, a used head that checks out is actually BETTER, it has already gone through many heat cylces of cooling and heating up. Iron "moves" with heating and cooling, it will reach an equilibrium after lots of cycles, at that point you have a head that is very unlikely to ever crack or go through head gaskets.

One of those rare instances where cheaper is also better :)

Re: Head conundrum.. used head vs. new bare casting

Posted: May 6th, 2008, 3:06 pm
by SilverXJ
but.. but... they don't make them anymore... and its rare?

Guess I'll stick with the used head that is seasoned.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 6th, 2008, 3:54 pm
by gradon
If you have a spare $200 and want to buy it, do it. You could always sell it for what you bought it for if you don't use it.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 7th, 2008, 5:50 am
by 1bolt
I can get a completely built (all valves, springs, retainers, new seals and guides) remaned head with 3 or 5 angle valve job for around $300 with no core charge.

Value is a tricky thing sometimes :) You'll spend more building that bare head as with anything that is commonly re-manufactured, the best value is often in the reman'ed part. Those companies are geared up and assembly lining parts usually at better than OEM specifications.

I can get a remaned flywheel for my YJ for less than what a used one on Ebay commonly goes for. People on Ebay see a flywheel for an AX-15 for 50 bucks and 20 shipping and they can't help but bid on the "bargain", meanwhile Autozone has them for $69 with a warrantee if it fails and the ability to take it back if it's messed up out of the box.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 7th, 2008, 5:32 pm
by aaronkeiser
Yeah I agree, I just helped raplace a water pump in my friends 98 camry. Reman water pump was 25$ and a brand spanking new one was 35$...I also replaced the timing belt, power steering belt, and AC alternater belt for another 30$. I replaced 3 belts and a water pump for 65$...Idk about you but thats a steal. I myself have no problem with used parts...psh pretty much all my YJ's swap parts are used and work great.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 7th, 2008, 6:13 pm
by SilverXJ
We are talking about a head, not a water pump. In my experience reman'd water pumps are crap. You used used parts for the belts too?

Re: Head conundrum.. used head vs. new bare casting

Posted: May 7th, 2008, 8:29 pm
by aaronkeiser
sorry I got off topic, I just wanted to share how cheap it was to fix. Used belts? No, I bought all new belts. We didn't use a reman water pump, it was brand new as well. As for head choice, I think it's obvious the head you already have is what you should use.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 11th, 2008, 7:34 am
by SilverXJ
Got the used head back yesterday. They said the guides are fine and no cracks. Started the polish and port yesterday. Got about 8 hours in. I'm going to do some more work if I can pry myself away from Powerblock and TopGear..

Re: Head conundrum.. used head vs. new bare casting

Posted: May 11th, 2008, 8:17 am
by John
Sounds good, go slow, give it the finger. :roll: :mrgreen:
John

Re: Head conundrum.. used head vs. new bare casting

Posted: May 11th, 2008, 12:04 pm
by gradon
I love me some Top Gear--one of the best shows on TV. I haven't seen any new episodes recently--but I did catch the one where they destroyed some guys yard. It must be nice to have BBC float the bill for their tom-foolery.

Re: Head conundrum.. used head vs. new bare casting

Posted: May 11th, 2008, 2:29 pm
by Flash
John wrote:Sounds good, go slow, give it the finger. :roll: :mrgreen:
John
Now that's funny :lol: :lol: :lol: :lol: :lol:



Flash