Im sitting here contemplating which route to take in a few months when I want to do my first big mod. Current mods are: Blackwing, LS6 intake manifold, B&B PRT catback, some kind of LT headers (probably do them within a month or so).

1. What is a realistic installed price for a cam (and aux. items) that will get me to ~400rwhp and/or 120mph traps? What will those aux. items be (springs, etc.)?

2. What kind of new rev limit would I need to use all that cams power (subjective on the cam but ballpark it)?

3. What is a realistic installed price for a 4.10 or 3.90 rear? DTE lists stage 1 at $1200 or $1550 installed. Since I dont live in IN, is $350 how much the install will cost at a different shop? Judging from how much stuff you have to drop to get at it, I cant imagine it's that cheap...

4. Will it be silly to do the cam without the gears considering how looong stock gears are? What kind of speeds would I be pulling in each gear with a 6500 rpm limit with Z06 wheels and tires? 6800? Will shifting to the next gear take me out of the powerband?

5. Estimate how long my stock, 23k mile clutch will last with 400 rwhp. Car will be used sparingly at the strip (maybe 3 times?), used for a few DE's and some auto-x's. Not a daily driver but street driving in between is normally...agressive.

Sorry for all the questions, it's a slow day at work and my mind is wandering.

 

1. Depends on how wild you go with a cam...
I would figure around $2k installed, including cam and upgraded valvesprings, retainers, pushrods, timing chain and and a full dyno tune.
Parts alone will run in the $800 range, then figure $700 or so for install labor and $500 or so for the tune.
Also, you may want opt for the UD pulley and ported oil pump, which are best done during a cam install.
With a milder cam, you may not need the full dyno tune, but it's still a good idea to get everything you can out of it.

2. Not really sure there's a cut n dry answer..but it should get bumped up to take advantage of the cam characteristics and what the upgraded valvetrain will allow.

3. Those prices seem very realistic. Just the R&R of the rearend housing should cost about $400-500 in labor, but the prices you listed also include the new gears and a complete rebuild of your existing rearend. To buy a new rear outright is well over $1k alone...and then it still needs to be installed. But then you could always sell your old rear and make some of it back.

4. If you're going to a really big cam (high duration) that peaks high ..gears would definitely be wise to give you back some low end torque that the cam will take away. It will make the car much more drivable on the street.

5. No guesses on the clutch. People have burned out stock ones with a stock engine at 20k. Others with 400rwhp might get 70k out of it. Driving style is everything, and the addition of more power isn't automatically a clutch-killer. Dragstrip use will definitely shorten it's life, as will slipping it excessively.
If you're doing a rearend swap, it may make sense to consider the clutch upgrade at that time, as there is a lot of shared labor there.

 

Excellent, thanks for the reply. So basically it sounds like both mods are about equal in price, especially if you figure in a new clutch when doing the new diff.

Dammit, I was hoping one would be significantly cheaper and help me make my decision.

 

If it's a "one or the other" proposition for you, I would suggest doing the gears first.
While not as "cool" as a lopey idle or a big # dyno sheet, it will put a bigger smile on your face driving around town and make a difference you can really feel..

Plus, you'll be all set when the time to put a cam in arrives.

 

Price really depends on how you feel about replacing and upgrading parts. You could go much further like I'm doing. Here's my breakdown of part prices:

$700 ------- Cam/springs/retainers/pushrods/seal
$80-130 ---- stock or coated & ported oil pump
$2-300 ------Rebuilt or Harland Sharp rockers
$275 -------- 2 piece timing cover
$450 --------ATI dampener

I don't know how much the timing belt is yet. Could go cheap with a LS2 chain, or go for a double roller adjustable chain. I'm also doing some other things since I'm pulling the heads, but I'm doing it to increase reliability and rebuildability: lifters ($200), ARP head studs ($150) and LS6 PCV system.

 

gears will give the most noticeable performance increase....