Fast road camshafts

[Mark 4]

I know that cams have been mentioned before but has anyone actually managed to source any?
Would anyone be interested in a group buy if we found someone to make them ?

[Wodjno]

http://www.rpw.com.au/shop/index.php?option=com_virtuemart&page=shop.product_ details&flypage=shop.flypage&Itemid=31&category_id =156&product_id=1329

http://www.rpw.com.au/shop/index.php?option=com_content&task=view&id=111&Item id=25

[Mark 4]

Cheers Glenn.

[Nutter_John]

make sure if you get cams them provide you with shims , and you'll also need something to adjust the fueling

[Mark 4]

Yup, it's all on the shopping list John.

[Nutter_John]

I'm sure that list is very long

Just as mine is , maybe we should compare sizes

[stuartturbo]

Is it worth trying the exhaust cams off the V6 na as this is a good mod that worked well on the vauxhall turbo engines
Could be a free worth while mod if durations and lifts match

[psbarham]

Is it worth trying the exhaust cams off the V6 na as this is a good mod that worked well on the vauxhall turbo engines
Could be a free worth while mod if durations and lifts match

guaranteed not to work, the N/A's are single cam per head

[stuartturbo]

thought there might be a twin cam jobbie

[Subaru ETA]

yeah we did this on my matat CA18DET. but yeah, the na v6 being a sohc engine would cause some probs!

[Eurospec]

guaranteed not to work, the N/A's are single cam per head

Its a good idea though.

You can do this on the GTO TT's using the NA cams in the TT's. Ultimately the mod was dissproven- but for the wrong reasons if you see what i mean.

Theory was that the NA cams had more overlap in them. Meaning the inlet and exhaust valves were both open for a fraction during the inlet stroke. Theory being that the out flowing exhaust gasses help to suck the inlet charge into the cylinder. Ultimately, this does work, and has the effect of a chunky increase in top end power at the expense of mid range torque. Boost does drop off (since you are now pushing a little unburnt mixture into the exhaust on the inlet stroke) but you do gain power without upping the boost to compensate.

The theory didnt hold in GTO's since it turned out there was no more overlap in the NA cams- infact iirc there was less.

Still if you want an idea of what difference it makes, i used to run std gto cams at std timing and my termnial 1/4 mile speeds (a good indication of horespower) were normally 128 ish mph. We added 4 degrees of overlap with vernier pulleys and trap speeds went up to 131ish mph. 3mph doesnt sound like much, but over that time and distance it is! Its probably 20bhp or more.

Cheers,

Ben.

[Mark 4]

Checked with RPW on the spec of their cams and they advised:

"We usually make them to a HKS 272 duration / 300" valve lift which has proven itself time after time"

So it looks like we have a choice of standard or these. The problem is though that I do not know if these are the best profiles/lift to go for. Years ago for bikes and also some cars there were choices from mild to wild so I have contacted a local manufacturer who cam make anything I want from billet steel.

So, can anyone offer me some guidance Pros vs. cons of differing duration/lift/overlap.

Cheers guys.

[Nutter_John]

Mark may be worth having a chat with Kevin @ AP motors as he is one of the only people in the UK I know off that has gone with uprated cams .

Personally if it was me I would be looking at getting everything else sorted first , get the car running to it's max , then look at doing cam's etc . But i can also understand the logic behind doing it up front as it's just one build then

[Wodjno]

Mark may be worth having a chat with Kevin @ AP motors as he is one of the only people in the UK I know off that has gone with uprated cams .

I thought Bonsai Boy had uprated cams in his Leggy

[Mark 4]

Yea, that's the thing John. I've sorted out a runabout and the Vr4 is slowly getting stripped out. I only really want to do this once but do it properly which is why I am courting as much opinion as possible. After all I am relatively new to the VR4 and a lot of you guys have so much more experience.

[zentac]

I had some reprofiled by kelford cams in auz (or nz), but when I went to fit them one of them was slightly bent so we never fitted them. I was thinking about sending some off to piper to get some billet ones made up.

[bradc]

Mark, Dave at RPW has said the price is about $2500 AU per set of 4 cams if you are interested.

[Mark 4]

Cheers Brad. Gonna hang fire for a while and see what other options I can turn up.

[zentac]

to resurect an old thread, we have put in some rpw cams this week, and already you can tell the car is breathing better. The gas is getting out easier, and the turbo is spinning up quicker.

Just doing some mapping on the road and we will be at the rollers on the 17th.

[Turbo_Steve]

Hi Zentac:
I think we'll be very keen to see a dynograph of what they've achieved!
What duration did you go for? I know you're headed off down the monster blower route, so 272s would not be unreasonable in your car.
I'm always worried that something as wild as a 272 will ruin the cars road manners: Everything I've used with more than 264deg seems to feel a little gutless at low RPMS before boost...though I've never tried them in a V6.