Are early non-intercooled 89-91 cylinder heads really as bad as everyone says they are? I've heard all about the bigger injector bores, cracks etc. I'm all set to have the head and block fireringed, and tapped/reamed for 14mm studs. Just wanting opinions on whether the head I have now is worth fire-ringing? A new style head runs about $800-900 when its all said and done/shipping etc. Piers no longer has the sale btw. Thats alot of money that could go towards something else. Thoughts?

 

Why worry if ain't broken! You can always start over if something does happen to the head!

 

When you pull the thing apart have it magnafluxed and if it has no cracks then go for it. If it is cracked then you would probably be better off finding a newer head from an auto dismantler, the newer heads are less likely to crack due to the smaller injector bores.

 

I believe you got fire rings mixed up. Im pretty sure you mean you want to get your head o-ringed not fire-ring. Atleast from what i have been told a fire-ring isn't something to do with the head or block it is something you do with the headgasket. A o-ring on the other hand does require machineing which could be done on the head or block. Also from what else i have heard they do not put o-rings on both head and block, just one or the other so if you are worried about your head cracking get your block o-ringed. Hope my info is correct!

EDIT: Fire-rings also require machineing but many people have not been as successful with them as o-rings

 

i know this is a diffrent motor but our International 706 with a 282 in it, every injector port has cracks. There are cracks between the valves and i a couple diffrent places. I know it dosnt sounds good but they are just hairline cracks nothing really wide but some are long. But we have been running it for prolly 3500 hours like that. I am not really sure if means anything with these truck because bigger motor and a turbo. Just a little input but i am prolly just ramblaming on

 

Give those of us that don't know what you are talking about an explanation of what these O-rings are, and what service they perform.

 

Explanation on fire-rings:
Look at a head gasket. headgaskets are usually made of some non metal material cork material ( for lack of a better term ). Then around each cylinder they have a metal "fire ring". Slightly thicher than the rest of the gasket and about a 1/4" or so wide. Runs around each cylinder hole. When a fire ring is done what they do is actually cut a groove in the block and the head (the same size) and install a ring that sits in both grooves.

Explanation on o-rings:
O-rings are a circular groove cut into the head ( or block ) and a wire inserted into it. The wire fits 1/2 in and out of the groove. The circular groove is positioned so that when the head is pushed down onto the head gasket, this metal o-ring pushes down into the existing headgaskets fire right, in a perfect circle, and right in the middle of the fire ring, helping it form a better seal.

How fire-rings work:
Fire-rings are where you cut the existing fire ring out of the headgasket and install your own complete fire ring. Instead of helping the existing fire ring seal better or be stronger you install a complete new and stronger fire ring.

 

Bill, if it hasn't cracked yet it probably won't. With all the heating/cooling cycles it's had all the stress is out of it and it's well seasoned. Assuming it's in good shape I wouldn't hesitate to put money into it. One that made it this far is a good 'un.

 

400K and no in mine why worry!

 

Wow Bill, its kinda funny how you get different answers to your question ain't it? So what have you decided?

Food for thought, when I was doing my last headgasket (3yrs), I priced a head from cummins and it was over $1000 for a stock remanufactured head. Boys at PDR could get me a new one with 60# springs for a lot less. I did not need a head at that time though, luckily.

Michael

 

Michael, yes thats why I love both these sites. You get more than just one point of view. I like JLeonard's post on tdr. I'm gonna call that Tri-state cyl head, see what they have to say. I'll probly start tearing apart the head next weekend.

 

Well I took the plunge. Ordered one from TriState in Evansville. Original equipment casting from Brazil. I'll let yall know how it looks when it gets here. I'm not sure whether or not I'm gonna have the block fire-ringed and tapped for 14mm studs. I might just have the head done and then use 12mm studs.

Make note, if you plan to bomb the heck out of a 1st gen, start with an INTERCOOLED model!! Won't need to purchase an intercooler AND cylinder head ..

 

Bill,

If you start with a intercooled truck then you don't get the non-IC VE pump I think that was a wise decision bill, i jumped on the boat as well and got a IC head.


Jeff