Hi guys,

what do you think about uprated valvetrains?
Are they needed if the bottomend can take much power and the heads are standard WRX MY99/00s?
7500 should be the rev limit, so no high rev engine!

Many thanks for your help!

 

anyone?!?

 

Confused do you mean you want to rev above 7500 or to 7500? The wrx heads should be ok up to 7700 if you’re using updated rods etc. The sti heads are generally 8 K -8250.

Up rated valve trains are generally only necessary when you go the full hog with high lift cams etc.

I think you need to be a little more specific to your application.

 

Hi mate,
I´m planing a stroked 2.0l to 2133cc and I wonder if I should make the long way with uprated valvetrain or will my WRX heads stand to the task?
Revlimit should be about 7.500rpms no more.
Many thanks for your help!

 

I would think your existing heads will be fine rpm whise...

 

So you think they will cope with the extra power the engine will produce?
I´m really thinking about the valves, as the more the engine can breath the more power can be produced...
The heads have to work perfect otherwise I can´t use the full power the shortblock could produce...

 

More a question of flow enough, what sort of power are you looking to achieve?

The valves are the same the same size on all classic heads as far as inlet exhaust diameter so this its self will not change with your head choice, unless you are considering BIG HP then there is no need to consider oversize valves.

The casing are however quite different and this determines the flow rate and ultimately increase or decrease VE. The 99 Head casings are the same as Sti v5 and have a good flow rate compared to the early phase 1 heads. So unless you are planning in excess of 450 I would leave them alone. And spend your money else where for now or just find some STI v5 heads with the sti running gear...

 

So you mean STI V5 heads are better (only from the camdesign) and I should go for them?
I plan to achieve 400 to 450 bhp hopefully, maybe 500?!

But if the heads can flow that air, I´m happy with them without spending big money on the valvetrain!

I previous asked about the differnece of STI V5 headas and WRX MY99/00 heads and got no information if this one or the other is better and what´s really the difference between them, anyways you said the heads are the same, so only camshafts seem to be the point.
And then I do not know which cams work better with a stroked shortblock...

 

The casings are the same, the running gear is not cams, springs valves and so on.

 

So so you think I could use my WRX heads for the power I want to achieve?