GN1R cracks

[forcefed3.8's]

I have a set of GN1r heads that have cracks going from the intake valve seats to the spark plug on all cylinders. These are first Gen heads with 14mm spark plugs. The cracks don't go all the way up the plug hole. Should I get them fixed, will they crack again, will it continue to crack more?

 

[forcefed3.8's]

Pics

 

[The Radius Kid]

If these are original series GN1R's,you could get them fixed,however you may find they'll crack again due to fatigue.
Maybe it's time to sell them to someone for lighter duty work - I watched your video,you psycho!
Tommy can fix them for someone else and you can get a newer set of castings.
The cost may be higher in the short term,but in the long run it'll pay dividends with much better reliability and less chance of collateral damage inflicted on other parts in the engine/turbo combo.

 

[tbone87]

If ya don't want to fix I will take and pay shipping lol

Posted from the TurboBuick.Com mobile app

 

[The Radius Kid]

Greedy opportunist!
They would make a nice pair of heads for someone building a stock block 4.1 though.

 

[forcefed3.8's]

These aren't mine. I am running regular GN1's not R's. They came off a 4.1 stage 2 TSE car. Double pumper became unplugged and melted #1 exhaust valve on the dyno.

 

[Nick Micale]

I have a set of GN1r heads that have cracks going from the intake valve seats to the spark plug on all cylinders. ...... The cracks don't go all the way up the plug hole. Should I get them fixed, will they crack again, will it continue to crack more?

There could be a serious disaster if those heads are used on any engine if the seat would come loose and not just trash the head, but the block and piston would also be part of the casualty?

The seat, or seats, need to be removed, cracks repaired properly, and new seats installed.

Even if that is done, the question of stress and structural integrity of the casting will have been compromised?

I only addressed the first part, "should I get them fixed"? I will not comment on your other 2 questions.

Since the new GN-1 heads use a 10mm spark plug which leaves a little more "meat" on the head to help prevent cracking in that area, that should give you a clue of what path to take?