Im looking at getting some cams for my Z when I rebuild and have been told to ask you for your advice on the matter.

 

How have you found them? Does it affect the driving in the lower rev range? I want to make my car as drivable as possible but I hear cams makes the lower revs a little difficult.

 

Thanks

 

Stuart

hi mate not the replie you where looking for, just thought id share an experience

 

had a GTI-R bout 2 years ago, ordered some special cams to be made (high lift)

 

never agian would I fit these to a road car.

 

the revs under 1500 were terrible to drive with, the turbo took longer to spool etc... I had them all set up properly and tunned to perfection but still they disagreed with the engine.

 

not trying to put you off mate or not saying that the zed will behave the same way.

 

just thought I would share this with you matie

 

 

 

Jim:)

Hi Stu.

 

I hear what ttop's saying and I know that's what you'd normally expect from some pretty lary cams - the idle goes out the window, it sounds blinkin awful, there's no torque low down and you have to drive like your ass is on fire to get any real power going.

 

But!... I can safely say I've had none of the above with the cams I've got. I talked to Pete (SE) about what sort of duration they are (and I can't remember the figures right now), because my mate Martin has some kick-ass cams in his M3. Pete says to get real power from a turbo'd lump you really *don't want* big duration cams because it starts having a nasty negative effect. So, my cams are the standard ones, re-profiled to give a bit more lift and duration - essentially, they shave a bit off the bottom (the wide bit).

 

To be honest, and this probably sounds a bit weird, I've never had so much low-down torque as I've now got. The idle is a bit high at the moment - could still do with a bit more setting up (one day soon!) and it definitely sounds different low down. Pete reckons the extra torque might be something to do with the bigger turbos having better flow than standard ones when they're off boost, and they probably also account for a bit more noise. I should expect the power to arrive later in the rev-range because of the size of the turbos and the nature of bigger cams - it's delayed but should come in much stronger when it's all coming together. But, so far, it doesn't feel like any of the changes have made it the pig to drive that you might expect. I say "so far" because I don't really know what it's going to be like at stupendous boost. Sh*t-scary, I'd have thought! Possibly the other reason it's feeling better low down is because my engine was never running right before. Standing starts used to feel horrible. Now I have trouble getting decent traction (with an autobox?!). It only takes a little flick of the accellerator to get the back out. I'm well impressed! :D

 

So in answer to your question: it feels great! You wouldn't get in it and immediately think it'd been cam'd up. This is a subtle fast-road re-profile of course. I can't imagine what race-spec cams would feel like, but I guess it wouldn't be nice. Depends how much power you're after - you'll probably get more peak bhp with race-spec cams but at the cost of driveability. Same thing with huge turbos... more lag but ultimately more power. Apparently you can play with the power band using a combination of cams and turbos - for ultimate peak power you'd want cams that come on at the same time as the turbos hit peak boost somewhere near peak rpm, but that's probably gonna make the power band quite narrow and means it'll be horrible low down. If you wanna stretch the width of the band (and lose a bit of peak) you can go for a set of cams that'll come on earlier. Or go for smaller turbos that spool faster with cams that come on later. I s'pose you really want a wider power-band with an autobox because the gears are longer. With a manual, it's probably easier to drive around a peaky engine but means you've got more chance to get it completely wrong unless you really know how to drive (at peak power, all the time! ;) ).

 

I'd recommend SE's fast-road re-profile, but would say be a bit careful about what you get if they're not SE's. I know Pete knows what he's doing, so when I said: I want a car I can drive every day, I knew he wouldn't give me a race-spec daily nightmare. I guess we'll see how it compares (overall speed-wise) with Maccas - which will have bigger turbos and should rev higher (right Mac?).

 

The down-side is the cams won't just slot in - hence the solid lifter conversion. You kinda have to know what you're doing to set this stuff up. I don't. SE do. I give cash to SE - job done!

 

Bit more like what you wanted to hear?

Thanks mate.

 

The Cams I have been looking at from the US dont need any modifying to use them, which makes me suspect they are just stock one with the profile ground out.

 

I think I will leave the cams alone then.

 

Stuart

Originally posted by 51x

I guess we'll see how it compares (overall speed-wise) with Maccas - which will have bigger turbos and should rev higher (right Mac?).

 

 

FACT!:D;)