(Duh! Can't type - obviously meant diff between '01 and '02 Zs)

Sorry, I'm sure this has been covered a million times, but I've just recently become interested in getting a Z06. What changes make up the hp difference? Also, what kind of stock rwhp are you guys getting and how much do typical bolt-ons increase rwhp? Thanks for the info!


[Modified by Tex71BB, 2:08 PM 3/7/2002]


[Modified by Tex71BB, 2:09 PM 3/7/2002]

 

I think the cam is more aggressive and the airbox opening is MUCH bigger, possibly the exhaust is throatier but they may be because of the above. At least this will get you back to the top. :chevy :seeya

 

Thanks, Silversport-

52 views and one response! - guess my questions were too stupid for anyone else to bother with. I'll poke around some other sites and see what I can find.

 

My suggestion is to drive both...Its the best way to decide in my opinion ..Good luck :cheers:

 

The o2's have heads up display and the memory option, hp rating is now on the Z06 badge. Electron Blue is new!!! Here are a few other things i got from another web site.
On the 02 they removed the close-coupled convertors up front (of the regular cats) "pups". The ’97-’01 under-floor cat used a single brick having palladium and rhodium as the reactive ingredients. The ’02 cat is a two-brick design. The front brick uses palladium and the rear brick uses a platinum-rhodium combination. This new cat, along with some changes in PCM calibration, allows the LS6 to meet LEV without pup cats and their exhaust back-pressure. There were other benefits, too. Going pupless means less cost and a 5.5lb. weight reduction.

With the mass air flow (MAF) sensor, GM did what Registry members have been doing for years–remove the air flow straightener or "screen". What took them so long to figure that one out? LS6 is not GM’s only application of that MAF. Any use of it with an intake duct that curves just before the MAF (typical of trucks), needs the straightener for the MAF to sense accurately and conventional wisdom was to leave it on Corvettes. In part, the essence of what Juriga and his engineers call "the ruthless pursuit of power" is whipping conventional wisdom.

With the Corvette’s relatively straight passage between the air filter box and the MAF, the straightener isn’t needed. Juriga told us it wasn’t until the MY02 development that his people questioned the MAF configuration in a Corvette-specific perspective.

There were no changes to either the LS6’s intake manifold or its cylinder heads. The intake manifold was already pretty darn good. We designed it to handle additional flow rates because composite intakes are very expensive to retool and develop. The same was true with the heads. The intake and exhaust ports flow sufficient quantities of air.

While the new catalyst technology is the revolutionary part of LS6 for MY02, changes in camshaft profile and valve gear are, also, a major part of the improvement. The ’02 LS6 cam is an evolution of the ’01 unit. While the ’01 has only .525-in. lift, GM designed the LS6 intake port to work well at .550 lift, which means the port had additional potential given more camshaft. Back when the ’01 LS6 was introduced, I viewed that as a clue of what was to come for MY02 and I was right.

The 405 horse camshaft has a more aggressive profile. In fact, it’s got the highest valve lift of any camshaft ever installed in a production small-block V8, Generation I, II or III. "We spent a lot of time developing a new cam," Juriga told us. The 405 horse camshaft has a more aggressive profile. In fact, it’s got the highest valve lift of any camshaft ever installed in a production small-block V8, Generation I, II or III.

The weight of each valve was reduced 23 grams. The ’01 intake weighed 99 grams and the ’02 weighs 76. The exhaust in MY01 weighed 86 grams but in MY02 weighs 63 grams. The exhaust stems are filled with a compound of 78% potassium and 22% sodium. "NaK" is unstable and may spontaneously combust when exposed to air with 50% or higher humidity. Do not cut open 02 Z06 exhaust valve stems.As a result of the more aggressive cam profile, the valve springs were, also, changed. "Even with the lighter valves," Juriga said, "we still needed better control because we open and close them very fast. The closed seat loads are the same–400 Newtons (90lbs) on the seat–but the open loads increase from 1150N (259lbs) to 1310N (294lbs) for both springs."

An increase in air flow significant enough to provide 20 more horsepower also demanded a small change in the engine’s fuel and spark curves. This was done with slight alterations in the PCM calibration.

There was no change in injectors or fuel pressure. In mid-April ’01, there was a change in the LS1/LS6 piston which will carry over to MY02. To address a limited amount of complaints about "cold piston knock", there was a small reduction in piston-to-bore clearance and new pistons, having skirts coated with a polymer, antifriction material, were introduced. The LS1/LS6 are first in the Gen III small-block engine family to use coated pistons. Corvette often leads the way with new technology that eventually sees high volume production. In the near future, all Gen IIIs used in GM trucks and passenger cars will have coated pistons–we’re talking millions of engines a year, here, not just 30,000 or so C5 powerplants annually.

During development, using Z06s with prototype, ’02 LS6 engines, there were a few clutch failures. The extra 15 lb/ft. torque put enough additional stress on the clutch that GMPT decided to upgrade the pressure plate. Clamp load was increased seven percent. This was accomplished by a change in the self-adjusting system inside the pressure plate. The result is an increase in clutch pressure from 2315 lbs. to 2475 lbs. There is also an increase in pedal effort that was deemed acceptable for a high-performance application such as the Z06.

The ’02 LS6’s additional torque output also had the potential to "bottom-out" the damper springs in the clutch driven-disc during clutch action. Damper spring rate was increased by 1.5 pound-feet per degree and a higher quality steel wire is used. Lastly, the disc flange plate (or hub) thickness was increased by twenty percent, from 5 mm to 6 mm.

The ’02 Z06 wheels are a tiny bit lighter and made by a different supplier using a new process but they carry over the "old" look. Speedline, the Italian company that does the magnesium wheels (RPO N73) to be discontinued at the end of this year, is the new supplier. Speedline is an industry leader in a manufacturing process called "cast-spun" and the new/old wheels are cast-spun aluminum alloy rather than the forged aluminum used in MY01. We addressed both those the same way.

We improved the ’01 rear shock valving to eliminate some of the choppiness you feel on certain road surfaces. That, also, improved ride.

The only other change to the Z06 suspension is the replacement of the steel, front and rear stabilizer bar links, introduced in 2000 on Z51s and used in ’01 on Z51s and Z06es, with aluminum links. This was done to reduce weight and causes no change in performance.

 

Thanks, Racer! Great info!

 

:cheers: :seeya

 

The 02 has a higher msrp, but since the economy has taken a dive, you can or could have taken advantage of the 2002 rebate. And even barter for an extra 4K off sticker!

 

Eh, the economy isn't THAT bad to get 4k off sticker on top of the rebate. Believe me, I tried! :D

Still got a good deal though. Certainly a lot better deal than the M3 I was considering.

 

The )1's burned oil.. while the 02's rattle :cheers: :cheers: