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Something wicked this way coming from HPR to the FNBADAZ06
C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
Yes sir, I have the close ratio TR6060 ZR1 transmission with the .81 and .67 5th and 6th gears
nice I’m mostly interested in 1/2 mile racing and fun around town. I want to rebuild the transmission with close ratio and now looking at you post I’m thinking 3.90’s... I’m also hoping my bottom goes so I can build a bigger short block. Very interested in this 468. Definitely looking forward to your dyno sheets.
nice I’m mostly interested in 1/2 mile racing and fun around town. I want to rebuild the transmission with close ratio and now looking at you post I’m thinking 3.90’s... I’m also hoping my bottom goes so I can build a bigger short block. Very interested in this 468. Definitely looking forward to your dyno sheets.
With my original Katech K501 cammed 427 (580 rwhp uncorrected), MN6 transmission, and 3.42 rear gear, I'd go thru the 1/2 mile traps in 4th gear at 163@7400 RPM with 25.5" tall 315/35/17 Hoosier drag radials, and 166.1 at around 6900+ (a guess, as I wasn't data logging at the time) with a 285/40/18 which is advertised at 27" tall.
The Hoosiers had me RPM rev limited, the 27" might have been a bit tall, but hard to say as both runs were done on different events so conditions changed.
My 3.90's will require a shift into 5th gear now, but the 5th gear is so much shorter now it won't drag my power band down into the toilet like a stock geared car does. Plus, with my added power and torque, I should be shifting into 5th way before the 1/2 mile so I can accelerate thru the traps.
At least on paper......real world testing should be available sometime in February
And, no doubt I have the superior gear and transmission for 1 mile racing........ it will be night and day there, with my car being in 6th and nearing the peak power production of the engine as I approach the traps, and hopefully tickling the 200 mph terminal speed in a standing 1 mile
With my original Katech K501 cammed 427 (580 rwhp uncorrected), MN6 transmission, and 3.42 rear gear, I'd go thru the 1/2 mile traps in 4th gear at 163@7400 RPM with 25.5" tall 315/35/17 Hoosier drag radials, and 166.1 at around 6900+ (a guess, as I wasn't data logging at the time) with a 285/40/18 which is advertised at 27" tall.
The Hoosiers had me RPM rev limited, the 27" might have been a bit tall, but hard to say as both runs were done on different events so conditions changed.
My 3.90's will require a shift into 5th gear now, but the 5th gear is so much shorter now it won't drag my power band down into the toilet like a stock geared car does. Plus, with my added power and torque, I should be shifting into 5th way before the 1/2 mile so I can accelerate thru the traps.
At least on paper......real world testing should be available sometime in February
And, no doubt I have the superior gear and transmission for 1 mile racing........ it will be night and day there, with my car being in 6th and nearing the peak power production of the engine as I approach the traps, and hopefully tickling the 200 mph terminal speed in a standing 1 mile
680/620 on Jeremy's setup with a MSD/102 combo that's limiting power production because it can't flow enough air to feed 468" ....peaked under 6400 RPM !!!!
I think this bodes well for me with the FAST hiram....and maybe a 108 tb too, to make some serious N/A power
Congrats to Jeremy on a bad *** HPR 468 setup that fits under a stock height hood !!!!!
I predict the Fast Hi Ram will allow your combo to peak @ 7000 RPM minimum. I believe it comes with 3 different length
runners and testing/comparing between them may be needed. The very large plenum without intrusions by the runners in the plenum
area combined with the straight shot to the ports will allow your 468" to reach its potential. I predict 800+ at the
flywheel and 700+ at the wheels. A 4.25" Stroke will make torque no matter what you do. Feeding the top end as demonstrated by
Jeremy's 468" is critical.
I base this from the 396" I had custom built (4.175" Bore X 3.60" Stroke) 11.7:1 Comp, MMS TFS LS3 Heads & Ported FAST with Mid-Length Runners,
LLSR 243/249 .680"/.645" 115+3, which made 690 @ Flywheel from 7100-7300 and carried to 7600+.
It was the best option for my goals, and to fit under a C5 Hood and spin that high.
I believe the Fast Hi-Ram will exceed the Holley Hi-Ram as well.
Looking forward to your results.
Good Luck.
The Hi-Ram has runners cast into the floor of the plenum. A bellmouth entry is better for flow and would give points to the FAST over the Holley. Unsure what really will play out though.
The Hi-Ram has runners cast into the floor of the plenum. A bellmouth entry is better for flow and would give points to the FAST over the Holley. Unsure what really will play out though.
Hoping we will be able to try all three version's of the runners available
FWIW your piston speed @ 7000 RPM is equal to my piston speed @ 8260 RPM LOL.
Your Discplacemt, Stroke, & Compression do not need runner Length to make torque.
4-6" will be plenty. Will be cool to see results from all 3 lengths. Do you know if they
are 2,4, & 6" ?
FWIW your piston speed @ 7000 RPM is equal to my piston speed @ 8260 RPM LOL.
Your Discplacemt, Stroke, & Compression do not need runner Length to make torque.
4-6" will be plenty. Will be cool to see results from all 3 lengths. Do you know if they
are 2,4, & 6" ?
I'll have to go back and see what data they sent us, but with the lid and velocity stack/runners easily removed and replaced, I'm thinking it should be pretty easy and fast to compare them while on the engine dyno.
There's even some discussion that we test using different length velocity stacks on individual cylinders for fine tuning, which then requires O2's on each bank during the test, but I don't know if that's going to be realistic and within my budget.
I'm aiming for peak around 7100 +/- 100, with a rev limit set for 7500-7700 RPM.
Waiting on final numbers from Rich at WCCH from flowbench test before cam selection can begin, but HPR has completed the assembly of the basic bottom end.
I'm putting a care package together this weekend to ship to them so that we are ready for final assembly..... electric water pump, Katech red oil pump, Comp valve covers, ID1050x injectors, etc.
Also, a refresher on head and cam/valve train selection when your aim is for a particular power band and RPM range...... mine is for peak power around 7000-7200 RPM https://www.enginelabs.com/engine-te...-of-11000-rpm/
Oh, and a reminder....... I'm now a 3.90 rear gear car matched to a TR6060 ZR1 spec MH3 transmission ....... 2.29/1.61/1.21/1.00/.82/.67
Rich says the valve stems are 8mm, and my Brodix heads are advertised to support spring diameters up to 1.650", but I was hoping I could run the new Comp dual conical spring package on my setup.
Hoping we can get them in
"The brand new, dual conical spring assembly from COMP Cams is the first product to bring revolutionary dual conical technology to the marketplace for wide-ranging applications featuring lifts up to .800".
COMP Cams is setting trends in racing once again with the release of its new Dual Conical Valve Springs. This progressive-frequency design (decreasing diameter from bottom to top) provides far better valve control than can be achieved with a conventional valve spring assembly, and it does so using lower loads due to a lower dynamic mass. Because the top coils are far lighter in a conical spring, less force is needed to control it. The result is better control, less deflection and fewer parasitic horsepower losses, thereby netting more power.
Meanwhile, heat, wear and friction at the highest stress location of the outer spring (the ID) are the most common causes of failure in racing valve springs. The engineers at COMP have addressed this problem as well. As opposed to dual cylindrical spring systems, COMP Cams Dual Conical Valve Springs require no interference fit to dampen spring surge. The self-damping characteristic of conical geometry, along with the lower spring kinetic energy of the upper coils, provides a game-changing breakthrough in valve spring design. COMP Cams Dual Conical Valve Springs are constrained at the top and bottom with stepped retainers and spring seats to separate the two springs. The result is that the springs' naturally progressive nature can provide outstanding damping without rubbing friction or the associated heat and surface damage. This progressive frequency also increases the RPM limit and reduces resonance concerns, while Superfinish surface processing increases lift capability and spring life. This feature has allowed COMP engineers to maximize load without increasing wire size.
COMP Cams Dual Conical Valve Springs are designed for circle track, road race and drag racing applications, as well as all-out, high-RPM street/strip hydraulic roller valve train systems with optimized lifters "
I'll be matching these to a custom hydraulic Comp cam, and I also purchased the billet Comp LS tall valve covers with integrated oil sprayers for the valve springs, to assist in increasing valve spring life and durability
I also need to decide if I want to switch to a 10% underdriven ATI balancer.
I lost my OEM alternator during a 1/2 mile event last year, which was replaced with several different "re manufactured" units from A/C Delco and Autozone. All failed within a few weeks when I spun the motor up to 7300+ RPM during my test runs.
I had heard that the re manufactured units could not stand up to repeated high RPM usage because of inferior bearings used in the rebuilds, which allows excessive heat to build up and allows the internals too much movement inside the case.
I also have friends who mostly run HPDE's , where engine speeds are almost always in the 5000-7000+ range for 15-20 minute sessions at a time, and they lose alternators on a regular basis. Many of them under drive the alternator as one of the fixes, but these are more track cars than street cars, so idling at a traffic light is not a concern for them.
I just bought a new OEM alternator before the tear down began, and with the switch to an electric water pump, I don't have the concerns of coolant circulation at idle and low engine speeds, but I'll also be adding to the electrical load on the alternator.
The underdrive balancer will slow the alternator down which appears to help significantly with bearing and overall life span (these things are expensive ), but I may need to upgrade to an aftermarket unit to supply the electrical demands of the water pump and the new Prospeed dual Spal fan setup I'm putting on the car.
12-18-2018, 05:47 PM
From the end of the runway, they were running anywhere from 168 to 172 MPH
), but I may need to upgrade to an aftermarket unit to supply the electrical demands of the water pump and the new Prospeed dual Spal fan setup I'm putting on the car.