Which are the more desirable? V3 underbucket heads or V4 overbucket?
Has anyone used either and if so at what power?

 

Kwik

V3 & V4 are the same, both run the shim in the top of the retainer with a bucket on top.

Best setup is to use newer age buckets with the shim incorporated with the bucket (1 piece).

To run these in V3/4 heads you have to modify & maybe look at top retainer to make sure shim of bucket doesnt foul retainer.

Is this the same build you contacted me on years ago?

 

Lol yes.

I thought one had the shim sitting under, the other on top? Is the cam profile the same?
What power have you seen from these heads Primeiro?

 

cam profiles are different between v3 and 4, iirc v3 are slightly more agressive

 

Any idea of expectations (powerwise) between the 2?

 

Hardly anything, I think ppl have run 600+ with either

 

Kwik

Are you concerned your engine power is going to exceed the capabilities of the heads!!!!

Glad your still @it and yes most of the time a project can mean years!

Both run the shim in the top retainer & I do not believe the v3/4 cams have any difference & if they do it would be next to nothing.

Tuners /some of my engines have seen over 700+bhp so they are the heads to have for a number of reasons.

However a lot of people have moved onto the VVC heads, you have more scope to tune in other areas due to the VVC.

Perfect for your setup & as you are aware the right parts with quality machining/engineering your onto a winner.

Keep @it.

 

Thanks chaps, guess it gives me the dilemma whether to sell my current V4 block with the heads on or keep them and buy some V4's elsewhere.

 

If you have a set that you know work/good condition go with them bud.

How far you got with your project then?

 

Well I have the blocks, piston's, crank and head-studs lol. Buying a TypeR put things back and getting engaged and arranging a wedding for this time next year have almost ground things to a halt. Con Rods next, then shells and then start looking at having it built.
Having a ready set of heads would help, whereas if I use the one's I have now I'd want new valve seals, re-lapping etc. I'd also be able to sell my engine complete a lot easier than just bottom end.