Well I now have a 422 ls6. What top end should I run?

 

You would have to re-sleeve the LS6 block to get that bore size. 3.905" is the largest that they say is safe. So I would think an LS3 would be cheaper unless you already have an LS6 block. Your heads would need alot of bowl work to work correctly on a larger bore as well.

 

The thing is a friend of mine has a sleeved LS6 that he will sell cheap to me and I'm not sure if I should buy it or not.

Would AFR do the bowl work for me or would I be better off having someone local do it? I wasn't sure if it would be worth having the 205's played with or if I'd be better off with a new set of 225s or 245s and selling the 205s.

 

The more cubic inches you have the better. Compare your costs for a complete running long block and decide what your budget is. Make your decisions and from there stick to them.

The AFR 205s would work fine with a 4.100 inch bore. I am sure Tony Mamo would tell you they would be a good choice for a large cubic inch engine. Would a larger head work better? That depends on what you are looking for. The 205s would be an absolute torque monster with instant throttle response and high efficiency.

 

Go cheap for the sleeved LS6 if done right by reputable shop/parts...You might look into bigger heads, selling your current set would free up good cash for a new pair.

 

Sounds like I might lean towards getting the sleeved ls6, and re-working my 205s. Torque is very fun.... plus it is cheaper for me to go this route.

Would anyone see any problems running the afr205s + N20 on a sleeved ls6 with the large bore? What stroke would you limit yourself to? 4.0?

Would a t-rex cam be fun in this application?

 

trex cam would work, but for your setup i would have a custom cam ground specific for your application. also i would sell the 205s and get a set of 225s or even look into the new 215s. I would definately give tony mamo a call or email and let him help you lay the foundation for this build. just my .02 cents..

 

I seen his thread on the 215s, that would be pretty sweet. I'll have to drop him a line.

 

Bump, I have have a 422 (4.1" bore) Ls6.

What top end, cam combos would you guys recommend for it, with say a 250-300 n20 shot?

I also have these good parts in my garage. MTI S1 Cam 244/244 .615 lift, 232/236 custom with .605 lift, AFR205s small bore.

Any chance using any of these with the 422 or should I sell it all and buy a set of 235's with a different big nasty cam?

Go!!

 

Well don't buy a cam until you decide what heads you are going to run. Your cam should be spec'd around your heads.

To answer your other question, of course those heads and either cam could be used. Will it yield the best results, NO, but it won't be weak either. Just not what you could make with the proper heads and a cam matched to the flow characteristics of the heads.

 

Looking for some suggestions then!

Example:

So say EPT240s with cam xxx should net you 575 wheel.