GN-1. What rockers?

[bob86gn]

Subject says it all. What are you guys with GN-1s running? Looks like adjustable rockers or custom pushrods are in my future. Did you have to relieve the pedestals? How is the geometry? Are you using the 8.85 pushrods from Champion?

 

[bob86gn]

ttt

 

[Eric Stage I]

I'm using the stock type. I bought the Sealed Power replacements, which seem to have beefier shafts. I did use the Champion pushrods. I've had that setup for about 1 1/2 years, and so far so good.

Eric

 

[Intercooler]

Bob,

You just need the correct length pushrods. Measure it out with preload and have them overnight them from www.cvproducts.com so I can see it run at Cecil

 

[Wolfj359]

I'm using the GN1 T&D 1.55 ratio rockers. So far so good, they look sweet too!

 

[bob86gn]

Thanks guys. Ordered the T&D for the GN-1 today, should have them tomorrow and hopefully running by Thursday night.

Jesse, I was going to order new pushrods but I still do not have any adjustment capability. My stock rockers are pretty worn and add to the reduction in preload. At least now I can adjsut them all to be correct instead of checking them all, averaging and still having some that are not right.

 

[Nashty]

My car with T&D rockers, GN 1 heads and a billet roller cam required 8.40 length pushrods. I had 8.5 which was way too tight when trying to lash them. I also use 1007 head gaskets.

Roger

 

[bob86gn]

Thanks Roger. BTW, car looked great in GMHTP.

 

[Nashty]

Thanks - guess it may be time to change the avatar though. My 15 seconds have passed.

You can get a pushrod length checker at most speed shops or order one from Powerhouse Products (Comp cams company). They are between 10 and 20 I think.

The reason I use the intake/exhaust method for lashing is I have a starter bump switch in the engine compartment and there is no tedious moving the engine till you get the engine on TDC. Besides, I hate the #6 hole as much as anyone so this makes it easier.

Another thing while I think of it. The T&D rockers don't require removal during a retorque so it is easier to do that if you choose. You do have to use a deep socket and I have the 12 point nuts on my studs which are smaller than the bolts. I'm not sure you could retorque with the bolts without rocker removal with the T&D's.

 

[bob86gn]

My GN-1 T&Ds are nothing short of beautiful. I wish I had clear valve covers for those babies!!! The fit and craftsmanship is very good. Thorrington bearing, solid rocker shaft and the extra cover over the pedestal to stiffen the installation was all well thought out.

Bob