Gen2 vs. Gen3 parts...Valvetrain

[Jon89LE]

Will any valvetrain parts off say my gen2 heads bolt to 3400 heads? They would be probably '00 heads. Would they bolt to any 3100/3400 heads? Thanks.

[Corpse]

I can't say I know from doing it but, it should work for some parts.

If you have roller lifters/roller cam you cannot use Gen 2 pushrods. You can use the valves and springs/retainers/locks but, the valves should be able to be used alone whereas springs/retainers/locks are a set. The stamped rockers must be used with guideplates.

Also, I dunno if the hardened the exterior of the pushrods for 3x00's that came with roller rockers so, it may be necessary to use older Gen 3 pushrods, btu, this is unlikely.

As for lifters, you of course, cannot use flat-tappet hydraulic lifters on a roller cam and, you cannot use the roller lifters on a hydraulic flat-tappet cam without having it reground to a new profile if possible, having your cam position sensor not work (unless you started with the newest 2.8 HO cam), and having the cam wear out very quickly due to it's horrible misusage.

As for pushrod guideplates, the 3x00 guideplates differ from Gen 2 in size and position. I would believe them to be interchangable but, I dunno.

The head stud is interchangeable for stamped rockers.

You cannot use the roller lifters and cam on a Gen II. Improper oiling, the need for a lifter anti-rotation device and also you will need different length pushrods. You can use an aftermarket roller cam in a Gen II though.

Sorry, I just get a little into it.

-Dave

[Jon89LE]

Im not talking about using gen2 parts on a gen3 block. Other way around. I have a gen2 3.1 and im doing the topend swap with 3400 heads and intake. Now i have an aftermarket cam, pushrods, springs, rockers, and locks which all bolt directly to the 3.1. So the main thing is just the heads, whether or not the springs will bolt to them. I know you touched base on the springs but you confused me a bit there. I know the valves are larger on the 3400 heads so if my locks wont work on them ill just use the stock locks on my current gen2 springs (if they will work). The other thing is the rockers. Will the CompCams 1.6 rockers bolt up if i use my gen1(ironhead) rocker studs?

[v6h.o.]

iron head and old aluminum head gen1 and 2 rocker studs swap over. guide plates bolt up.
gen 1/2 and aftermarket COMP and Crane rocker arms can be used, and old style springs or performance springs can be used as well.

IF you are keeping it a GEN2 block and GEN3 heads with the adjustable rocker studs you CAN use stock GEN2 pushrods.

[geoffinbc]

Yes bolt on you Gen II stuff to the Gen III heads. Valves are the same stem so you can use the locks from either. All you have to do is cut the pushrod guides out of the gasket so they do not touch the metal GenII guideplates.

Remember when Lloyd and i put the Crane rockers on his 3400? Well you are doing almost the same thing.

[Jon89LE]

Thats really good knews. Its going to make this swap a lot cheaper then. I was under the impression that when i got the 3400 heads i was going to need to buy all new head components. And Colin, thats what im doing, keeping my gen2 block with gen3 top since my gen2 block already has the pistons and work done to it. So is it final now, my Gen2 head components (minus the valves) will work on the 3400? .

[geoffinbc]

There are 4 guideplates bent one way and 2 bent another. Be sure you swap accordingly. You cannot really screw it up. But some people may have ways to do it.

[Jon89LE]

I Gotcha. I didnt see your message when i sent that reply. You didnt have any clearance issues with the Gold Rockers and the Gen3 valve covers did you?

[Jon89LE]

By 4 one way and 2 another, do you mean on the gasket itself?

[geoffinbc]

Not the valve covers. It was the intake that had issues

as you can see the rocker really don't protrude very far. The covers fit great.

[geoffinbc]

4 Metal Gen II guide plates are shaped a like and 2 metal guide plates are shape another way but alike as a pair

[Jon89LE]

Alright. Im not 100% sure on this guideplate thing since i have never seen them but im sure ill manage . For the manifold, i take it those shiney spots are what you ground down for extra clearance?

EDIT:
BTW, thanks for the help. I pretty much now have a better idea of what to run now. I dont think ill have enough for the Crane rockers so i may just use the Comp 1.6s. My computer tuning will cost around $350 so i need the extra money.

[geoffinbc]

Yea the shiney stuff is where we die grinded the metal away. At the end you will be left with about 3/16 to 1/8th of material. We found that the rocker needs the most room in the closed position and as the valve opens the rocker moves away from the inake. So focus on the closed position of the valve.