can 1.7:1 full roller rockers be used on a 3400?

[jaons_Wlp]

The search engine on this site doesnt work at all so i have to ask. Can i use these 1.7:1 roller rockers with minor modification?

http://www.summitracing.com/parts/cca-17021-1/overview/

It would be $155.64 for a set of 12 which would be well worth the gain. I assume i would have to use conversion studs, stronger valve springs, and hardened push rods, or can i get away with stock parts? will valve clearance be an issue? i want to order them so i need answers please. thanks

[GhostGALA1]

I'm not sure if those rockers will work or not. I'm new to the Chev game. For the same price you can get these CompCams 1.6 roller rockers for the 3400 V6. http://wot-tech.com/shop/gm-60v6/com...1/prod_33.html

[Guest]

The search engine on this site doesnt work at all so i have to ask. Can i use these 1.7:1 roller rockers with minor modification?

http://www.summitracing.com/parts/cca-17021-1/overview/

It would be $155.64 for a set of 12 which would be well worth the gain. I assume i would have to use conversion studs, stronger valve springs, and hardened push rods, or can i get away with stock parts? will valve clearance be an issue? i want to order them so i need answers please. thanks

To use those, you would likely need to get the Comp conversion studs, (and gen2 pushrod guides) that have 10mm thread on the bottom and imperial thread on the top for the adjuster nut. They would likely fit easier than the Crane Gold Race Rockers, but might still need some clearancing, to each other and the intake manifold.

The valve springs are a known weak point in the 60 degree V6, so I would recommend upgrading them, there are several ways to go. Currently I'm running Comp 215s on my engine, and they slipped right on. Rocker geometry will need to be checked at time of install, where you may or may not need custom length pushrods.

I'm not sure if those rockers will work or not. I'm new to the Chev game. For the same price you can get these CompCams 1.6 roller rockers for the 3400 V6. http://wot-tech.com/shop/gm-60v6/com...1/prod_33.html

Those rockers will not work (easily) on the 3400. The 3400 doesn't use a stud that those rockers would use, they use a pedestal and a bolt. Stock 3400 rockers have roller fulcrums. The stock rocker is a better choice over that one IMO.

[jaons_Wlp]

thanks for the reply. the rocker arm threads in the 3400 heads are 10mm? do those gen II rocker guides bolt on? i dont want to order them and find out they cant be used..

[Guest]

thanks for the reply. the rocker arm threads in the 3400 heads are 10mm? do those gen II rocker guides bolt on? i dont want to order them and find out they cant be used..

It depends on the year of 3400, early 3400s do have 10mm thread, but later ones, I want to say starting in about 2002, the thread was reduced to 8mm. You can drill out and tap the heads for the larger thread if need be.

I have fitted the guides to a 3400 head, though I have not gone as far as actually using them. I've just used the stock rockers so far. I haven't found a need to change them out yet, though I was talking with a friend of mine today that runs a machine shop where we discussed this, and will be looking at seeing what direction I go for full roller rockers. The small amount of reduced friction over stock isn't enough to change them on their own, and I may not need or want to change the ratio. If you're thinking of retaining the stock cam though, I can see why you'd want to go to 1.7 ratio rockers, for the increased lift and slight increase in duration.

[Xnke]

No real reason to go to a roller-tip rocker unless you're running a pushrod/valvestem height combination that puts a lot of scrub across the valve tip. Get the pushrod length, pedestal height, and valve stem heights correct and there's really no reason to not run the stock pedestal rockers...and they're cheap, too.