-turboinduction+Apr 29, 2005 - 3:17 PM

Because at a certain point, you need new valve springs, which cost money. And the length and duration affect the RPM range and idle too I believe. I don't know if what I posted is correct though.

Catcams are listed for the 20 valves but better to keep the head stock (no parts in north america)

Claude

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...me=STRK:MESE:IT

218 whp @ 7 psi

Claude

hrm - seems like I'll have to do a little more research on cams and springs.

-Ti

With cams, you have to watch the overlap. Overlap is when both the intake and exahust valves are open. More overlap=better top end and worse idle. That's why they made VVTi, it increases the overlap later in the RPM band so you have the best of both worlds.

Anyway, with a turbo you DO NOT want a lot of overlap, because the exhaust will actually backflow into the cylinder (because of the pressure built up against the turbine). However, going with higher LIFT cams is fine. The problem there is you put a lot more pressure on the valve springs and you need high performance ones... and it's more wear and tear.

Those are the basics anyway.

This post has been edited by raven_101: Apr 29, 2005 - 9:57 PM

So stock overlap would keep VVTi in check, but maybe check the possibilites of higher lift (with new springs). Now, should a turbo 20v disable the VVTi and just go with adjustable cams?

-Ti

A lot of people do that, yeah.

-raven_101+May 2, 2005 - 3:58 AM

would you suggest this?

-Ti

if your still looking for pistons the guys over on club4ag.com are getting a group buy together for ROSS pistons might want to check it out