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Heads again --

Posted: July 30th, 2013, 2:29 pm
by heavy equipment
Is there a known weakness in the #2686 head, other than intake/exhaust flow issues? I have two of them, and am considering using one on my grandson's '89 Cherokee, but I don't want to use one that is prone to failure.

I appreciate any advice, thanks!

Re: Heads again --

Posted: July 30th, 2013, 2:58 pm
by Cheromaniac
The 2686 head isn't prone to failure. It's main weakness is that the intake ports are low so airflow suffers. With a good port job on both the intake (especially raising the roof on the intakes) and the exhaust side they can perform pretty well.

Re: Heads again --

Posted: July 30th, 2013, 3:06 pm
by honkysXJ
Why not do a 4.0 head ?,they're plentiful at the yard I did see you said you have a couple of the 4.2 s but supposedly the 4.0 head swap is good for 20hp and there's a few castings that can take a beating

Re: Heads again --

Posted: July 30th, 2013, 3:50 pm
by heavy equipment
Actually, the two 2686 heads U have are on 4.0L engines. One is in an '87 Cherokee and the other is out of my '90 that I put the 4.7L stroker in. The '87 I got cheap for parts. The freeze plug had blown out from the rear of the block, and the previous owner tried to fix it without pulling the engine and finally gave up.

I've found a couple heads for sale at around $200-$300. I'm thinking let my (broke) grandson have one of the older heads and when I go to build another engine I'll get maybe a 7120 head for it and go to the Chrysler ECU.

Thanks for the advice, I'm still deciding...

Re: Heads again --

Posted: July 30th, 2013, 6:28 pm
by IH 392
heavy equipment wrote:I've found a couple heads for sale at around $200-$300.
Is that reconditioned ready to bolt on??

Re: Heads again --

Posted: July 30th, 2013, 7:45 pm
by heavy equipment
IH 392 wrote:
heavy equipment wrote:I've found a couple heads for sale at around $200-$300.
Is that reconditioned ready to bolt on??
I doubt it; I have some seat cutters and having the valves ground is fairly cheap. Of course, the valve guides' condition is also unknown. Rebuilt heads seem to run around $1500.

Re: Heads again --

Posted: July 30th, 2013, 8:11 pm
by SilverXJ
Just for a reference I recently picked up a used head that needed work. $120. Needed exhaust seats, valves, valve job, milled. $400. Don't know who is asking $1500 unless it includes a real polish and port.

Re: Heads again --

Posted: July 31st, 2013, 6:44 pm
by IH 392
I keep on shopping! I picked up my 7120 head for $40 off of craigslist (with a header and dampner) and a 0630 for $20 at the last swap meet, both complete!, I even picked up my '99 longblock with the intake for $200

Re: Heads again --

Posted: August 4th, 2013, 6:49 pm
by cruiser54
You'll be fine with the 2686 on a stocker.