GN1's- Yes or No?

[STP]

Gene, I have a set of GN1R's sitting here. Did Champion put any other exhaust guide in their heads? I am not familiar with the K-line stuff. Is that the type of guide? They are brand new bare unported heads. Should I go ahead and have the exhaust guides replaced? Thx Scott

 

[geno]

Yes Replace them
The K-line is a iron guide with a thin bronze or brass lining that hangs to far down into the port. The problem is they are in the flame path and have no way to disapate the heat. The heads dont have enough material built up around the guide to soak up the heat are are just hanging out in the flame path. Alot of aluminum heads have some extra support molded into the port around the guide to transfer the heat. Some people have had good luck with the k-line but nobody i know has had good luck with these in the GN1 heads. Send them to Bill Anderson if you want to have somebody fix them thats done alot of them this way My buddy bought a new set of heads from Champion and checked the k-line guides to find them hour glass shaped with .005 in the center. If he would have just bolted them on his new motor it would have smoked in no time. Dont get me wrong i like the heads but sometimes (All the time for me)a guy needs to make sure things are right for himself The only heads ive done this to were not "R" heads and im not sure if they have the same problem

 

[STP]

Hrm...Thx for the info Geno. May need to give Billy a call "again" to see if he knows what guides these R's have.

 

[humberto]

Go with the GN1s.

 

[aperrego]

Originally posted by geno
Yes Replace them
The K-line is a iron guide with a thin bronze or brass lining that hangs to far down into the port. The problem is they are in the flame path and have no way to disapate the heat. The heads dont have enough material built up around the guide to soak up the heat are are just hanging out in the flame path. Alot of aluminum heads have some extra support molded into the port around the guide to transfer the heat. Some people have had good luck with the k-line but nobody i know has had good luck with these in the GN1 heads. Send them to Bill Anderson if you want to have somebody fix them thats done alot of them this way My buddy bought a new set of heads from Champion and checked the k-line guides to find them hour glass shaped with .005 in the center. If he would have just bolted them on his new motor it would have smoked in no time. Dont get me wrong i like the heads but sometimes (All the time for me)a guy needs to make sure things are right for himself The only heads ive done this to were not "R" heads and im not sure if they have the same problem

So Geno,

IS this just with the alums or do the irons have the same issue???

Thanks!~

 

[geno]

Its not cheap by the time you do a good valve grind because the guide never ends up exactly were it was. The guide likes to push off the port wall and thats why you need to have Bill or somebody thats up to speed on this and how short to cut them.
This could save a PITA you MIGHT go through later When i did mine i had to make custom guides because you cant find the perfect size. You just order a guide thats to long and cut it down then turn the step back on the end for the lead and leave the tapper off. You have to put the leed back on it or it will push off the port wall really bad and wont even be close to center

 

[geno]

If they have K-lines and hangout to far in the exhaust port
I know if you run a shortend valve guide you loose support and less area for heat transfer but mine has lived just fine (Along with a few others on this board) But like i said some people have zero problems like this but im not sure if they drive it on the street as much as me and my friends do

 

[turbosam6]

Well, Nick talked me into a set of Gn1's, so here we go. He's going to look at the valve guides for me, so all should be well. Going with cometics and ARP 190,000 psi bolts.

 

[AsphaltAnihil8r]

Originally posted by turbosam6
Well, Nick talked me into a set of Gn1's, so here we go. He's going to look at the valve guides for me, so all should be well. Going with cometics and ARP 190,000 psi bolts.

Cant wait for all the good news,,I just know that thing is gonna be a monster when your done ....Lots of luck...

 

[86brick]

Originally posted by turbosam6
Well, Nick talked me into a set of Gn1's, so here we go. He's going to look at the valve guides for me, so all should be well. Going with cometics and ARP 190,000 psi bolts.

Nick knows best

 

[Two Lane]

Originally posted by turbo nasty


Mr. Conley said that he has been

having a heck of a time getting

the alum heads to

stop leaking water,

and he was pushing the champion iron heads.

What's the cure for leaky aluminum heads?

 

[Two Lane]

Originally posted by paul vilser
These were the GUIDES, not the seals, and the heads were bought less than 7 months ago. I was told the spec is a tolerance of from 1.3 to 1.8 and the "tightest" measurement on both heads was 4.0!!!

...for $1,700 you'd expect better quality. I was really dissapointed.

Did Champion fix them free for you when you notified them?

 

[Two Lane]

Originally posted by paul vilser


I would be wary of Champion heads.

Mine smoked on a new motor.

My engine builder pulled the heads and found most valve guides were way out of spec. He had to put in new guides to fix the "diesel" look.

They have poor quality control at Champion, thats for sure.

If you do get them, check them first before you put them on. YOU are Champions' quality control check.

My performance was great but it's embarrasing the way the car smoked like a piece of crap.

I even got to the point of coming early to our cruise spot so no one would laugh at the smokey old Buick (with a 12k new motor!!!).

I noticed in Bowling Green that a lot of them smoke... so buyer beware! Paul

Wow!

How much do you need to spend on them as soon as you take them out of the box?