schmendog

iTrader: (10)

Due to budget constraints, I have to sell my TFS 215 heads and instead use some 241's I have that have a fresh valve job. Goal is 900 - 1000 WHP with twin BW's on an iron 347, LS6 intake, Martin cam etc.

I realize the obvious benefit of keeping my TFS heads, but I really need that money Ill get from selling them. How much potential HP am I giving up using the VJ 241's instead of the TFS, if say everything else besides the heads is the same at 20 PSI?

punishmentcycle

iTrader: (6)

n/a prolly around 25-30hp +/- on a turbo setup prolly double that if not more.

pwrtrip75

iTrader: (8)

Run .25psi more of boost and make up for it. Problem solved.

PUNISHER TA

iTrader: (13)

you can make up for it with the custom cam. But I was surprised at how much restriction my stock heads had in my setup. I was seeing 31# of boost on a 6.0L with an s475, which we know has to be boost "stacking"

schmendog

iTrader: (10)

That what I was originally thinking, but with stock heads potentially lifting I will probably be limited to 20-22 PSI based on others results. So, Im limited with what I can make up for on boost with the stock heads.

Wicked69

Not if u run head studs torqued correctly and LS9 Gaskets. I have it 25lbs on one or two occassions and no sign of lifting a head. My heads are 799 completely untouched. I do think 20-22psi with your set up will be super close to 800rwhp anyways. Dont sweat using the stock heads.

schmendog

iTrader: (10)

Good to know man, I was under the impression stock heads dont do well above 20 PSI. I'll be using studs and LS9 gaskets so sounds like I might be OK with the 241's.

Wicked69

I think that is mainly because of too much compression, no headstuds or improperly torqued head studs, and not enough gasket. At least that is how it seems to me. I was 11.0 compression on stock 6.0 using the 862 heads untouched. I was pushing 25lbs and that was definitely pushing the limits but it still lasted 7 months. lol Oh and that was without an IC and NO meth injection either. Just pump E85 and a bad tune. lol

itsslow98

iTrader: (18)

Was the cam speced for the TFS or 241s?

schmendog

iTrader: (10)

It hasn't actually been spec'd or ground yet. Waiting till I decide on the heads and a couple other things.

punishmentcycle

iTrader: (6)

lifting heads has nothing to do with the actual head.(unless the mating surface wasnt flat to begin with) heads lift because of insufficent clamping force of the hardware used.

Torqueshaft

Technically you are correct if we were talking about a solid chunk of metal...To get it to "lift" would require insufficient clamping force or the stretching of the hardware used.

But I believe what most are referring to when they talk of "lifting a head" is "pushing water" which can happen even with the proper clamping force, if there is high enough pressure to cause distortion of thin head decks on some heads.