How much horsepower does one need?
 

I've been reading up, trying to understand the tradeoff between cost, risk of breakage, and the various HP levels (C6Z06). Usage is mostly street romps with some 1/4 miles. I've still got 2 years GMPP warranty, and have been avoiding mods because of the exhaust valve issue, but this is feeling like too long to wait so I'm thinking of doing aftermarket heads with SS valves and moving along.

It seems 600 whp is reasonable without needing forged internals for reliability?

It seems that 600 whp with DR or slicks is not advised and half shaft, drive shaft need to be upgraded for reliability?

I've not driven a 600whp car and don't know if this will be enough to satisfy my itch. I don't need to be able to spin the tires for 100 feet at 80mph

I would like to have enough power on tap that it was the drivers's challenge to position the throttle so as to avoid serious spin at any speed up to 90 when above 3000 rpm.

Will 600 whp be enough on Michelin PS, or do I need more? If more, how much?

I'm considering a ttix kit where I could turn it up later on.

You might try and find one to drive first to see if it will be enough, traction becomes a serious issue at that hp level. You will need the proper tire set up to put the power down, even on a Z06, 200 whp difference is a big difference.

IMO 600-700 whp for the street is ideal.

I think the most common answer is; "a little more than what I have now". That applies in pretty much every case.

Very helpful, I know.

Just had ESC install a "mild" SL1500 kit on my 05. 560 rwhp/528rwtq. My current tires are 305/30/19 Invos. I can spin them at almost anytime. Driving the car is a whole new experience. Around town it's like a showroom stock car. For "spirited" driving I have to ease into the pedal and really work at being smooooooth. 3rd gear pulls on the highway from 70 is unbelievable compared to stock. :thumbs::thumbs::thumbs:

http://i212.photobucket.com/albums/c...ps5a45b035.jpg

1000rwhp + is Ideal!!!

:thumbs:

Thanks, so at 650 whp what ancillaries need to be upgraded for reliability (besides heads)?

What he said :rock:

that is a pretty number, nice and even......:lol:

I would say my Eforce kit and Kooks headers and hi flo cats produces very similar results to this post except I have Michelin Pilot Super Sport tires that are a little harder compound than his Invo's though. At this level and above is where we see less experienced drivers start to get into trouble and end up on YouTube.

Ditto :rock:

want.

Thanks for all the feedback but I don't think 1000 fits my requirement of reliability and I think it's oing to require all kinds of extra parts, transmission upgrade and brace, meth kit, new block, etc.

I'm trying to set the HP goal where I don't have to change the whole car and sacrifice reliability. I think this is 600-650range. c6 cyaa and thomasmoto made comments that lead me to believe this is going to be enough to meet my goals

Whatever you end up with, I highly recommend that you have a reputable tuner set up your car, because (especially with the Z06 LS7), there are several horror stories out here. It seems to be far less forgiving to engine mods than the LS3.

I would search the forums and read up on them, so that you can discuss (and resolve) your concerns with your builder/tuner.

To your question, from what I've seen over the years of the C6Z06 production, 550 - 600 rwhp is the accepted practical "reliable" limit for power levels out of a STREET driven vette drive train.

And at that power range, you will have traction issues, especially when you turn the nannies off. You should be spinning pretty easily already if you put yours in competition mode.

When you get above the 600 rwhp range, or do a lot of drag racing, you had better be seriously considering stronger clutches, half shafts, different engine internals, trans/diff upgrades, etc.

At 600+ whp you will want to run a drag radial (I believe Nitto NT05R fit the widebody rear). With a DR, you can make real use of the 600 whp and not have to ease into your acceleration. Having WHP that just makes street tires spin is useless to me...you may as well step it down in HP. Street tires do not work well at 600 whp.
Invos are crap...I got rid of mine in about 1 month.

The only horror stories have been these items: tune, 2pc valves dropping, rocker arms coming apart, rod bolts needing replace at higher hps. In general, where the op wants to be at power wise, the 427 stock with aftermarket heads, cam will get you in the range your looking for. At 600-650rw, the stock SB should be fine mechanically. Tune is Key!!!

IMHO, anything over 600 rwhp on the street is a waste of money. My ProCharged C6 makes 550 on a conservative tume. I could push 600+ if I wanted, BUT, even with 305 Invo's, traction is non-existent in 1st and 2nd gears. On cool days, 3rd gear can also be an adventure. I've had my car try to spin me at 80 mph with massive wheel spin on a day with cool tires and cool pavement. I guess the big hp guys are running around town on drag radials with 10 psi in them. Thats nutz.
I realize that some guys carry a laminated dyno printout in their car and say, look at this! But, unless you are a racer, save your money.

Some guys will say 500 is too much, other will say 1000 is just getting in the ball park, only YOU can answer that question, but if your asking it you will probably be fine in the 550-600 range. :thumbs:

As much as you can afford and hopefully more then the other guy

500-650 is more plenty for the street.:thumbs: