[PICS] Katech Track Attack Z06 SN#048 breaks chassis dyno record
-Highest rwhp NA car ever built by Katech
-Highest rwhp NA car ever on Vector Motorsports' dyno
We just wrapped up this Z06 with the following:
Track Attack LS7 engine (11.85:1CR)
FAST intake
CF Valve Covers/CRB
NW 102mm TB
ARE Stage 3 dry sump system
Halltech CF112+SuperBeehive
RPM Level V + Quaife
Exedy twin disk clutch
Dewitts radiator
Corsa exhaust
572rwhp/547rwtq on 93 octane
592rwhp/573rwtq on 104 octane
Vector Powercal cable to switch calibrations so the customer can easily switch between fuels
My impressions:
I am shocked at how well this car drives. It has the GM Stage 3 cam in it so I didn't expect the drivability to be very good with 40 degrees of overlap. I've driven a couple other cars with the cam, the Katech LS7-powered Camaro SS and Everett's Mosler MT900KR. Those cars both had higher gear ratios which put the cruising rpm at a point which is more tolerable with the GM Stage 3 cam. With the Z06's 5th and 6th gear ratios I was concerned that the bucking at low rpm low throttle input could be intolerable. It's not. I attribute that to a few factors. The car is equipped with all of the ingredients that really help to smooth out a big cam. First, it has a Halltech Superbee CF 112 intake with the MAF forward design. I've noticed that this slightly improves the drivability of the Torquer cam on my car and it's even more of an improvement with the GM Stage 3. I believe the MAF forward design moves the MAF sensor futher away from being buffeted by cam pulses. Second, it has a 102mm intake and throttle body. This also seems to help with smoothing. Third, it's got a lighter clutch. Based on my experience it seems that the lighter clutches do not lash the drivetrain as much when the cam starts to buck the engine. It seems that if you have a larger mass on the end of the crankshaft it can get into a rhythm and compound the problem. Fourth, I have to commend our tuner over at Vector (Steve) who really has this thing dialed in as much as good as it can get. You can't cal duration and this things got a lot of it. I can cruise at 1500rpm and with throttle modulation can keep the cam bucking to a minimum. I've driven the car at 1200rpm and it drives, it just doesn't like being that low.
As far as power, I know on the internet if it's not over 600rwhp people are not impressed, but in the context of our chassis dyno these numbers are staggering. When our Torquer cam makes 515rwhp on our dyno and RichieRich makes 582rwhp with the same cam, I'm convinced this is at least a 630rwhp car on other dynos. Is the car fast? Frankly I have no idea. With MPSC tires in 50 degree Michigan spring weather, if you get your foot anywhere near the throttle the tires light up. From a roll I was never able to exceed half throttle. On a hot track in the summer time this car will be a menace. I foresee a big wing in this customer's future.
There is nothing better than the small of Sunoco GT Plus in the morning.
__________________
_Jason Harding
Director of Aftermarket Operations, Katech Performance
As for the power, I AM impressed. I can't count how many guys dyno 550, 570 etc on other dynos, yet still have the same 132 mph trap speed that I have on street tires with 513 on Vector's dyno. Yes, I realize it is just peak but still, you see my point. I agree, that Vector's dyno doesn't glorify any numbers. Having been on it and at the track plenty, I think its safe to say its one of the most conservative dynos around.
Last edited by ConfusedGarage; 04-15-2011 at 11:02 AM.
Very nice build. My guess is this will be a track car that is liveable on the street. What I liked most was the 540 ft lbs average over the entire power band. Most of the guys with the cams that give them the big numbers don't have nearly this much torque from 3500 to 5500. That is where you normally pull from exiting a corner. Carrying a little more exit speed pays big dividends at the end of a straight where it can make a lot of difference in whether you can pass a car or get stuck behind a car that is just barely slower than you. Jason, what was the difference between the two runs?
Gary
Location: Supporting the Corvette Community at Abel Chevrolet in Rio Vista, CA 707-374-6317 Ext.128
Quote:
Originally Posted by 40YRW8
Very nice build. My guess is this will be a track car that is liveable on the street. What I liked most was the 540 ft lbs average over the entire power band. Most of the guys with the cams that give them the big numbers don't have nearly this much torque from 3500 to 5500. That is where you normally pull from exiting a corner. Carrying a little more exit speed pays big dividends at the end of a straight where it can make a lot of difference in whether you can pass a car or get stuck behind a car that is just barely slower than you. Jason, what was the difference between the two runs?
Gary
I think the first run is the 93 octane run and the second is the 104 octane run.
Jason, you are correct. The Super Bee MAF Forward design reads the airflow a couple inches from the velocity stack built into our huge K&N Filter. You might think this is counterintuitive to getting streamlined airflow, but you would be wrong. I designed this intake with the sole intent of feeding the larger throttle bodies and having zero issues with turbulence at the MAF read area.
This filter design promotes laminar flow at the MAF and can only be disturbed by open holes in the radiator shroud left over from Callaway or LPE type radiator cut-outs. It is recommended that you get the stock shroud if you have a prior cutout.
The stock NACA duct opening does not affect the MAF read negatively. The Beehive captures the cold dense air from the outside and fills the filter area with ram air (ambient pressure) keeping vital spark advance where the factory wanted it.
MAF meters must read the airflow in a straight laminar fashion without turbulence, if they are expected to estimate the mass of air accurately. MAF cross sectional area is key to long term fuel trim averages getting dialed in as well as MAF meter placement within the induction system.
MAF meters are the first report of the airflow, the O2 sensors decide whether or not to add fuel or take it away, after the combustion process. The long term fuel trim averages, are mearly a record of how much fuel was over or underestimated by the MAF sensor. Understanding how to fool the MAF slightly, is the key to better horsepower/tq. in the real world vs. the engine dyno.
GM has improved their MAF design in recent years, with golf ball like surfaces on the surface of the MAF wire horn. This new design, seen on the CTS-V intake has less surface area and a much cleaner designed metering pickup.
Lastly, we have no obstruction to flow near the throttle body. Having the MAF forward design, we came up with the idea of relocating the PCV clean line as well. It runs from the dry sump canister to the filter bottom, which is pretty important when you are racing. Pressure build up can overwhelm the dry sump system causing overfilled oil reservoirs to puke oil back into the clean side, which ends up in the intake system.
One footnote, is that MAF tuning is required with the SBCF112. The SBCF102 comes pre-tuned, so no ECM recalibration is necessary.
Corvette Store
[PICS] Katech Track Attack Z06 SN#048 breaks chassis dyno record
)
YOUTUBE
FACEBOOK
MAILING LIST
