I have a base 2008 C6 automatic. I love the gas mileage and the stock horsepower. I'm not a hotrod (anymore) but would like more power under the hood. I want to install a cam for the added horsepower and not disrupt gas mileage (much) and still be drivable without adding headers. Here's my question. Would the Z06 or Z51 cam give me the added horses without having to add headers, tune, etc.

I would add headers at a later date but want to keep the car somewhat factory, a sleeper so to speak..... Thanks for your help

 

Don't waste your time with a Z06 cam.

Headers and a tune will be your best bet. You'll pick up ~30rwhp and gain ~2mpg.

 

If headers are part of the long term plan, do them first and select a cam that matches your needs. Doing a cam first is going to result in a less optimal situation at some point: either the cam is designed to compensate for stock manifolds and is optimal for now but not what you would choose to use with headers, or the cam is designed for headers and is suboptimal now.

Headers and a tune will add power and may even improve normal driving mpg. My LGs with cats are quite and would not eliminate any sleeper status, not that a vette is a typical sleeper.

 

pretty much though I can't confirm the gain on mpg with headers, with headers and gears I lost 1.0 mpg.

Don't waste your time with a cam without headers either. You're crippling the cam where it shines, above 4500 rpm, with stock manifolds and cats. It's a waste of time.

A cam will cut your around town mileage by 2+ mpg, more if you are idling a lot. Not as much on the highway. And your exhaust will stink because of the cam.

Headers and gears are by far a better option if you're not taking your car to the track all the time. You don't feel a cam on the street other than the cool sound. I just did a big thread on it showing dyno sheets to prove my point.

http://forums.corvetteforum.com/c6-t...ast-heads.html

 

While I generally agree with you (as shown above), I think it is not that simple.

Most cams do make much more difference above 4500 rpms, but it is because most people camming their car want max performance in the higher rpms and buy cams that provide it. If someone wanted to keep the same HP curve as stock (i.e. peaking by 5800 - 6000 rpm), they can pick a cam that would provide more HP from 2500 rpm and up. Most do not do this as the car will be faster by achieving higher average HP in the upper rpms. An LS2/LS3 cammed for 6300+ rpm peak is going to achieve a higher average HP than an LS2/LS3 cammed for a 5900 rpm peak. A 10% gain in HP at 3000 rpm might feel nice on the street, but the fact is the car is not making enough HP at 3000 rpm to want to start a race at that rpm. There is a tradeoff to be made in cam selection and for most the result is they go big enough that the low rpm does not benefit.

If the OP wanted to keep stock manifolds to pass visual inspection, he could still benefit from a cam swap. The cam would be selected with that in mind. The total overlap would be less than max effort cams used with headers and extra exhaust duration would probably be used. There is no doubt that a something like a 218/230 116 .600 would provide a nice gain over stock and make more power from about 2500 rpm and up. I'll totally agree with your comeback which is the same gain could be achieved with headers and w/o the possible downside loss of mpg that comes with a cam. However, knowing the car will pass visual inspection and looks stock is priority for some folks.

I would have posted something similar in your mod thread (excellent post, BTW) for discussion, but it has long changed directions.

 

^^ No arguments here.

I guess I did let my thread get sloppy. Guilty as charged.

On this topic....a cam swap or a gear swap is around $2500 mas-o-menos.

To spend that for a small cam that is designed for stock manifolds isn't enough bang for the buck in my meter.

Gears, on the other hand, are as you will feel them every time you step on the gas.

If you're going to go with the downside of a cam - less mileage, less drivability, more exhaust smell, might as well go big and get the benefits, or don't bother.

And as I wrote in my post, the best bang for buck mods IMHO are the tire mod, for the particular track at hand, combined with the driver mod. Our cars are much more capable from the factory than 99% of the drivers ever experience.

 

I agree. The car with bolt-ons seems to be in a sweet spot. Headers/CAI/tune and gears + tires add a lot of fun w/o much downside.

OP: If you are just bombing around town, some 3.15s or 3.42s and decent rear tires will add a major fun factor to the car.

 

Thank you all for your imput. made everything much clearer for me. I will do the headers and tune first.......................

 

Cold air intake too

 

If you want a real sleeper, you can add a high stall converter or gears and a hi stall converter. You will get a big boost in performance without touching your stock engine. Another bonus would be your car will perform even better if you later decide to add a cam & headers to go along with your converter & gears. A Yank SS3200 or SS3600 would be my choice.

 

I wholeheartedly agree with this. I missed that the OP has an auto...with an auto, a high stall converter provides incredible performance, like a second off the quarter mile, combined with sticky tires. And it's brutal on the street too, without hurting anything except stop and go mileage perhaps.