HEAD BOLTS

Ironmen77

#1545
Does anyone know where I could get some head bolts at a reasonable price, for a '90 xj with a 4.0L? Summit, NAPA only show bolts for a '96 or newer.
5-90 thinks they should be the same bolts as far as he knows. Does anyone have first hand knowledge of this one way or the other?
The Jeep dealer I talked to wants $218.00 for the '90 set.
 

OkieXJ

NAXJA Member
NAXJA Member
How did those bolts work out for you Ironmen? I'm looking for a set and none of the chains and rockauto appear to sell them and hesco is twice as expensive.
 

fabjunkie

New member
I ordered mine from ARP. The only thing is the ones on the drivers side do not have the threaded portion sticking up to put the injector harness thing on, BUT the upside is they do not have to be replaced and can be used over and over.. So far I've had the stinking head off twice, so that is definitely a selling point for me.

PN 112-3601 $54 from Summit
 

winterbeater

New member
I ordered mine from ARP. The only thing is the ones on the drivers side do not have the threaded portion sticking up to put the injector harness thing on, BUT the upside is they do not have to be replaced and can be used over and over.. So far I've had the stinking head off twice, so that is definitely a selling point for me.

PN 112-3601 $54 from Summit
Do they say WHY they can be used over and over? Why are they capable of that when the stock ones can only be reused once?
 

badron

New member
Why are they capable of that when the stock ones can only be reused once?
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The head bolts are a grade 8 bolts. By standard any grade 8 bolt must retain it's ((MIN)) specification for a (((MIN)) number of 5 torqueing to it's recamended max stretch. They can and do survive much longer. Said standard only set the MIN requirements.
Often bolts are replaced because you just don't know how many time a bolt has been reused. Not a bad idea at all. The PO of a JEEP may not want to tell you he/she has already had the head off a few times reusing bolts.
BUT ((((IMO)))))) if you know how many times a bolt has been used and/or you have removed the head for reason that would not be caused by bad head bolts. Replacing a bolt of one or two uses is crazy. This just one or two time used head bolts has proven itself. You are replacing it with a seldom tested bolt.
All this is IMO
 
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joe_peters

New member
Good point, but if the bolts recommended max stretch exceeds the available area, especially after the head has been surfaced once or twice--or the block has been decked once or twice, then you have head bolts that are going to bottom out and while they may "torque" they won't be applying that "torque" to the head.

There usually are very good reasons for the specifications and warnings contained in the FSMs of various manufacturers. So, as long as you remember HE WHO IGNORES THE SPECIFICATIONS PAYS THE PRICE, then do as you will.
 

winterbeater

New member
I like the point of the "seldom tested bolt". With many cheap imported parts now, that makes sense to me. I worked in a boltmaking plant about 30 years ago where we had mixed stock (wrong coil stock) in the bolts we were sending Detroit Diesel for the main bearing bolts. They didn't like the bolts breaking as they torqued up the main bearings. And how much of this stuff comes from China now?
 

joe_peters

New member
I like the point of the "seldom tested bolt". With many cheap imported parts now, that makes sense to me. I worked in a boltmaking plant about 30 years ago where we had mixed stock (wrong coil stock) in the bolts we were sending Detroit Diesel for the main bearing bolts. They didn't like the bolts breaking as they torqued up the main bearings. And how much of this stuff comes from China now?
You are so right about the import stuff!

ARP isn't way expensive, about $57 at summitracing.com for the kit.
 

badron

New member
Hang in there. Our bitchen is starting to pay off. Importing of auto replacement parts from China drop off last year. We may even see "Made in the USA " again
I would love to drive a car that was at least 90% American made again. Other then a Honda. Before I take that last ride.
 

fabjunkie

New member
I would suspect the ARP ones are made of superior material, hence they wont stretch to the point of being junk after 2 uses.. I don't know the real answer, but I will call Sam and ask..
 

magimerlin

New member
OK little late but...

First hand experience here. The bolts for the 96 and newer 4.0 WILL FIT the older Renix heads with NO ISSUE. The ONLY difference in the new ones is that 2 of them have the stud style head that is used to align the v/c gasket. I used the newer ones on my 89. I compared ALL the bolts and the lengths are exactly the same as the newer ones. Only difference is the one stated above....

And these where the Fel-Pro head bolts that I used...
 

fabjunkie

New member
Hey guys..here's a follow up to this earlier bolt dilema.

I went ahead and bought a 112-3601 kit which is for the 258 motor. the kit comes with all 4.5" bolts. For the 4.0 we need 7 of them at 4.5, and 7 of them at 3.75". I had to call and order 7 of the shortr ones from ARP, so no biggie. $23 plus freight.

I also talked to Sam with regards to the "two uses" lifespan of the other bolts out there and he said it is because of the material. The ARP bolts are made from superior material and they engineer their bolts to torque at 75% or less of the yield point. So in other words, they never stretch so much that they are unusable. He said any bolt that recommends throwing it out after "x" amount of uses is made with the torque point and the yield point of the low grade of material too close to one another.

In other words, once the bolts are torqued a number of times, the material stretches so far that it will not come back to spec, and therefor it is a throwaway item.

Interesting info I thought.
 
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