Whats the average prices these days?

Who shall i use?

 

your gonna have to shop around pal,just what is a stage 1 tune?i bet it varies greatly,have a look on puma raceing engine's website..........still your in the right place for advice..........

 

IIRC.... Stage 1 is just ported inlet, Stage 2 is Ported and Cam'd, Stage 3 is Ported, Cam'd, and oversize inlet valves.
I think thats right........ not much else you can do to a head!
I supose some might fit a Cam before porting but each to their own.

 

i thought freak power was your mate why not use him?

 

No real point to having a Stage 1, no real advantage over std.

 

i would of thought it would be the exhaust ports that would need opening up first as the inlet side is forced.

 

No point really, the valves are already too big for a start, plus, the gas will always find its way out anyway.

 

the hot exaust gas is easyer to expell than the cold inlet mix. hence on all cilinder heads the inlet valves are bigger

 

i can see what your saying but the exhaust side will choke before the need for ported inlet and bigger inlet valves but thats just from my own experiences.

 

jamsport charge Ł450+vat for there ported head and is good for over 300hp

 

not to sure tbh i just got a flash back from coldge of the teacher explaining why the inlet valve is all ways bigger

 

How much !!

I've upset him recently and he's not talking to me for something i said on the forum

I would use him as his work is top notch but as i said above i can't

 

the way i see it is you are forcing the air into the engine with your turbo so you wont see as much of a gain on the inlet side as you would on the exhaust side,and the quicker you get the gas out the quicker you can start the process all over again.
p.s im no expert tho.

 

[QUOTE=Johnny Knoxville;3964633]How much !!



Ł450+vat lol

 

that is true, but if the air turbulates too much in the ports then it effectively reduces the volume of air/fuel as the molecules are hitting each other and creating vacumm gaps within the mixture.

 

sorry for putting my foot in it then.

i've seen his work and was very impressed too

 

Nope, opening up the inlet is exactly what you need to do! Very restrictive on the CVH head and huge gains can be had from correct porting of the inlet side.

Spot on there mate!

Not on a CVH head mate, the exahust side is not restrictive and will flow till the cows come home! lol The only part of the exhaust side that eventually becomes restrictive is the turbine wheel and that is why you then fit a bigger one (Stage 3 T3 has .48 for example), or fit a bigger turbo all together (like a T34).

You will see a huge gain, by increasing flow your boost pressure will drop as will your ACT's meaning you can make more power easier (less chance of det).

On CVH heads the Inlet ports are opened up to match the valves and the exahust ports are only polished if touched at all (helps the gasses escape easier by reducing friction) most are left unmodified because they are already way over spec'd for the engine and can quite happily flow over 250bhp's worth of exhaust gasses. In fact IIRC the flow limit of the exhaust ports and manifold has not been reached yet.... but dont quote me on it!

 

jamsoprt charge 350+vat for a ported head and they are on the shelf

 

also tho a piston coming up the boar is going to fined it alot easyer to force the gases out compaired to the turbo having to force the boost presure in