Which cams?

[DaveGT 0]

Hello all. I'm looking to give my obd2 highline engine a freshen up with new rings, bearing shells, valve stem seals etc. basically all the wear and tear parts. While I'm at it I'm looking to add a decent induction kit, 6-branch manifold and quality stainless exhaust system. I've decided to pop some uprated cams in too as I'd like a little more mid range punch. My question is which cams do people recommend here for what I want and also how much power can I expect from these mods with a decent remap to take them all into account? I'm looking to supercharge it next year too hence the freshen up so would whatever cams I choose work and benefit the supercharger?

Thanks in advance

Dave

[DaveGT 0]

Anyone?

[wardycatt 7]

I believe that 268s are popular (and that Schimmel is a quality brand mentioned quite a lot on here), but that people recommend 263/4s for cars that use forced induction. It depends on the results you are looking for, in terms of increased mid range punch. I suppose it depends on your definition of mid-range etc.

I personally don't have ANY experience regarding cams, I'm just chucking in my opinion because no-one else has got back to you. There appeared to be a decent set of 268s in the 'market place' section of the forum last week (hollowed out, making them lightweight and therefore better for higher revs), but I think these are now sold.

As for power - coupled with a good quality exhaust, air intake and remap, I would guess that you'll be touching 200bhp or maybe just over that. I have this setup (minus the cams) and 191bhp was my last rolling road output. I read a discussion on here the other day which seemed to suggest that 212bhp was about the max. achievable on a naturally aspirated 2.8 VR6 OBD2 "AAA" engine - but that was using forged pistons and all sort of expensive accoutrements. So approx. 200bhp is my best guess.

There's no shortage of threads on this subject of cams on this forum (and others), but you'll probably have to do most of the digging yourself. It's a subjective issue, and depends on your particular setup.

Personally, I'd skip the cams and focus on the forced induction. The power gains to be had are far more interesting. (6) once the 'charger is in, I reckon you might forget about cams... for a while, at least. However I can see the logic of adding parts if you're overhauling the engine anyway.

Hope that's of some use to you.

[DaveGT 0]

That's brilliant. Thanks for your reply. 200bhp would be enough to keep me happy until the time comes to charge the old girl

[DrRich 1]

I would agree with wardycatt here. The cams do make a noticeable difference in top end; suposedly some low down grunt is lost but I didn't notice. Schrick 268s are the common upgrade, giving a decent bit of extra power and still a smooth idle (on my OBD2 anyway).

For forced induction, you are fine with the stock cams, as 'bigger' ones just blow the mixture out into the exhaust and waste power. 'Proper' forced induction cams would be best of course (I think they have more intake duration but less overlap).

The best naturally aspirated setup is a Schrick VGI manifold and 268s, allegedly deigned to work together and complement each others' shortcomings. Having run this combination, I can say that they do work well and give an excellent power band with only a bit of a 'notch' at around 4000rpm where the manifold switches - not a problem though, just noticeable.

I've now gone down the Rotrex charger route and it is certainly addictive - lots of power (especially fun in a Mk2 shell!). I was lucky to find a good used setup at a reasonable price though. They're not cheap new.

I'll be selling my VGI and 268s when I get around to it. A fair price seems to be about £1200 for all this, but then power upgrades are never cheap!