Rickof08

I have a 03 z06 and I'm looking into doing a cam swap. Ive been searching all day but I cant find any info on what cams I can run without changing the valvetrain. I would like a cam with a noticeable idle but would prefer one i can just swap in without upgrading other things. Any ideas or is this even possible? I dont daily drive the car, it goes out the local car meets on friday and thats about it, so Im not worried about how well it does at low RPMs.

warren s

Its possible, but its a borderline waste of time. The stock cam is almost as aggressive as the valve train can handle. Its a decent amount of work for fairly small gain if you only want to swap out the cam and nothing else.

Any major cam manufacturer can advise you in making a choice. I had good luck with a Texas Speed (TSP) cam.

A mild cam with an LSA of 112 would give you a lopey idle. Once you go past the stock cam specs for your car, the valve springs become a weak link.

Rickof08

Thanks for the reply. So I need to stay within .555 .551 but try to find a 112lsa? I just want to make sure Im understanding before I start searching.

skyavonee

What do you have against upgrading valvetrain components along with the cam?? You can get a cam package including springs and pushrods for only $600 from Texas Speed. That's a very reasonable price and is the bare minimum you'll want to install.

warren s

I would contact one of the vendors for specific numbers.

I have a 228/228 588/588 @112 LSA. The vendor, and my research told me that the stock springs would not handle the lift for long. That goes for both the stock springs on my 99, and the yellow springs on your 03.

I am not sure at the actual cut off where the lift is too much for stock, but if small enough of the difference that the stock springs can handle it, its not really going to make that much more power.

Rickof08

I guess I should change them out while Im in there anyways. 600 isnt bad, the best Ive been able to find for kits including springs is 800 bucks. Ill check into Texas Speed

warren s

Once you get into, it grows into a major project.
I also wanted to do just a cam,.... and then heads.
Replaced the lifters, push rods, timing chain and gears, oil pump and did the Comp Cams rocker trunion upgrade. I also needed new head bolts and gaskets. The heads came with new springs and retainers.

tlove32

You could do the gm hot cam - 218/228 .525 .525 112....it should work with stock springs

Rickof08

wow the hotcam sounds nice! may be a stupid question but who carries the gm hotcam? is it actually a gm product?

ctusser

Yes its a gm product.

slvrzo6

In my opinion you're wasting your time and money with out upgrading the valve train.. Spend the money once and do it the right way, or twice and learn the hard way.

Rickof08

I spoke to a local tuner about it and he has me convinced to do a cam/springs/pushrods kit. He told me he has several gm hot cams laying around the shop that unsatisfied customers had removed. next week hes gonna have a sit-down with me about doing a custom grind cam based on what I want out of the car and whats already done to it. Thanks for the help everyone

AU N EGL

New cam must also have:

New Springs
New timing chain
possible new push rods. ( stock ones bend quickly )

tblu92

I would NOT go with the GM "hot cam" It is an old grind and there are so much better cams out there now---And unless you have real tuning software-they are notoriously hard to tune
IF it were MY car I would always change the springs
I would always install moly push rods
I would always install a NEW cam sprocket and chain
I would always install a NEW oil pick-up O-ring
Depnding on your miles I would install a NEW oil pump as well (say over 75K)
I like installing a160 or 180 thermo while everything is out
If you have the $$$ it would be a great oppurtunity to get an under-drive balancer-(it's a cheap and effective 8-10 RWHP throughout the ENITRE RPM range)
For your application it sounds like something in the .230/.230 range would be great--I would keep the lift under .600 just for longivity-- As mentioned the LOWER the LSA is the more lopier the idle--I believe stock is something like 119-117---114 is a good choice for an A4 as the higher idle requirement will be smoother and your "brake hold" issues won't be as bad
With a 6 speed it won't be an issue so a 112 would be perfect !!!!