have got a set of v3 sti cams and was thinking of having them reprofilled before fitting them. any ideas what i should go for regarding duration and lift.
thanks

 

What is the engine spec and what are you going to use it for?

 

[QUOTE=Dyney]What is the engine spec and what are you going to use it for?

spec so far:94wrx engine, omega pistons,arrow rods,arp rod bolts,hks headers,3" exhaust,fse fuel reg,up-rated fuel pump,hks intercooler,RCM lightweight pulleys,RCM lightened flywheel,6 speed box.

ready to fit:garret gt35/p20 turbo,v3sti ported and polished heads,v3sti cams,850cc injectors!?,steel v4sti head gaskets.

gonna be mainly for strip use.

 

bttt

 

Leave the cams alone, the Sti3 ones should work nicely as they are, and any reprofiling worth doing will require new valve springs, retainers and the heads to be re-shimmed.

The injectors may also give you problems on a 2.0.

Paul

 

The injectors may also give you problems on a 2.0.

what problems do you speak of?

 

Possibly too big? Does this give a poor idle and low speed because they flow so much and would need to be set at very small duration?

George

 

850s can run on a 2ltr but you may have to drop fuel pressure in order to get a decent idle (or up the idle speed). Both are compromises. 850s are also a little large for a gt35 comp wheel anyway.

As you are using an FSE reg then 740s at stock pressure would be your best bet. Should allow for upto 2bar boost, dependent on map sensor. (550s maybe ok at a higher base pressure, but you would certainly run out of headroom with that reg). Depends on what boost and fuel you decide to run.

Agree with Paul re cams.

 

I am not sure that lowering the fuel pressure will help (unless you have actually tried this jason?) I find improved idling on my 2.5 with slightly than standard higher fuel pressure as it gives better atomisation.

The 740s are the way to go.

Paul

 

Alot depends on fuel temps and type (and cams for that matter), but dropping pressure by ~0.3 helped especially once warm. However I run stock pressure now (and idle at 1100rpm). Either way it's not ideal.

One way to combat poor atomisation is to run a huge pump and a low tank (or dump the return into a swirl pot) That seems to warm things up

 

my car is phase 1 so i thought i could only get 550 and 850cc injectors for this!?