Corvette ZR1

[ogg vorbis]

by now you all know about the eaton tvs s/c. i'm disappointed with this engine. forg gt's regularly rip off the tvs and install a whipple...you can't do that with the ls9. installing a smaller pulley is a diminishing returns deal...i learned that from owning a supercharged buick gs. the intake manifold is horrendous. i also don't like the intake ports, and piston shape.

even magnuson is putting out ls crate motors with 800+ hp on premium gasoline. a kenne bell screw s/c with larger pulley makes more power on less boost, with less air heating, less parasitic loss. a pair of borg warner s258 turbos would have obviously kicked ass - 600+ whp on the same boost. early ls9 development used turbos, and were near 700 hp.

omg...the nissan gtr ran the 'ring in 7:29!! an overweight, nose-heavy, small-tired, lower powered car embarassed the zr1. the zr1 will obviously do well on the 'ring, but imo chevy better do lots more tuning before it goes on sale in september!

[epaulo]

Originally Posted by ogg vorbis

by now you all know about the eaton tvs s/c. i'm disappointed with this engine. forg gt's regularly rip off the tvs and install a whipple...you can't do that with the ls9. installing a smaller pulley is a diminishing returns deal...i learned that from owning a supercharged buick gs. the intake manifold is horrendous. i also don't like the intake ports, and piston shape.

even magnuson is putting out ls crate motors with 800+ hp on premium gasoline. a kenne bell screw s/c with larger pulley makes more power on less boost, with less air heating, less parasitic loss. a pair of borg warner s258 turbos would have obviously kicked ass - 600+ whp on the same boost. early ls9 development used turbos, and were near 700 hp.

omg...the nissan gtr ran the 'ring in 7:29!! an overweight, nose-heavy, small-tired, lower powered car embarassed the zr1. the zr1 will obviously do well on the 'ring, but imo chevy better do lots more tuning before it goes on sale in september!

u know the gtr is underrated correct? u realize the gtr dynoed well over 400awhp, thats at all wheels, so that thing is pushing well over the 500hp mark, a 500+hp car w/ awd can kick lots of cars ass's. if nissan underated the spec v as much as they did the gtr then the spec v is pushin alot more hp as well. link to the dyno if u dont believe me http://youtube.com/watch?v=yIhsv6WSboY

[firefighter]

Originally Posted by ogg vorbis

by now you all know about the eaton tvs s/c. i'm disappointed with this engine. forg gt's regularly rip off the tvs and install a whipple...you can't do that with the ls9. installing a smaller pulley is a diminishing returns deal...i learned that from owning a supercharged buick gs. the intake manifold is horrendous. i also don't like the intake ports, and piston shape.

even magnuson is putting out ls crate motors with 800+ hp on premium gasoline. a kenne bell screw s/c with larger pulley makes more power on less boost, with less air heating, less parasitic loss. a pair of borg warner s258 turbos would have obviously kicked ass - 600+ whp on the same boost. early ls9 development used turbos, and were near 700 hp.

omg...the nissan gtr ran the 'ring in 7:29!! an overweight, nose-heavy, small-tired, lower powered car embarassed the zr1. the zr1 will obviously do well on the 'ring, but imo chevy better do lots more tuning before it goes on sale in september!

Just a few things to clarify. Realy I'm not picking just saying. The Eaton on the GT was a Radix 112HH and the one on your GS was either a M62 or a M90 while the 112 is more efficient than either the 62 or the 90 they are all inefficient in comparoson to the TVS the early models were 3 lobe with up to a 60* twist to the rotors where the TVS is 4 lobe with 160* twist the efficiency on the TVS S/C's are in the 70%-75% range the older versions were at max 60%. Also the GS was non intercooled where the LS9 has a very efficient IC even in comparoson to the GT. The TVS was launched mad 2007 and there still models unavailable. Also Magnuson uses Eatons they are just starting to release TVS kits. And the manifold for a roots style S/C doesn't need to be too sophisticated it just has to flow and get the air where you want it runner design is not all that important. Also I would not have minded them going TT I think it woulda been pretty cool personally I would rather get a ZO6 and sent it to Lingenfelter. Oh and if you want a little info on the TVS se the link below.


http://www.eaton.com/EatonCom/Produc.../TVS/index.htm

[epaulo]

Originally Posted by firefighter

Just a few things to clarify. Realy I'm not picking just saying. The Eaton on the GT was a Radix 112HH and the one on your GS was either a M62 or a M90 while the 112 is more efficient than either the 62 or the 90 they are all inefficient in comparoson to the TVS the early models were 3 lobe with up to a 60* twist to the rotors where the TVS is 4 lobe with 160* twist the efficiency on the TVS S/C's are in the 70%-75% range the older versions were at max 60%. Also the GS was non intercooled where the LS9 has a very efficient IC even in comparoson to the GT. The TVS was launched mad 2007 and there still models unavailable. Also Magnuson uses Eatons they are just starting to release TVS kits. And the manifold for a roots style S/C doesn't need to be too sophisticated it just has to flow and get the air where you want it runner design is not all that important. Also I would not have minded them going TT I think it woulda been pretty cool personally I would rather get a ZO6 and sent it to Lingenfelter. Oh and if you want a little info on the TVS se the link below.


http://www.eaton.com/EatonCom/Produc.../TVS/index.htm

i'll take a whipple, twinscrew for the win

[firefighter]

I dunno see a TVS in action and you might forget all about that twin screw Lysholm/whipple.

[ogg vorbis]

Originally Posted by epaulo

link to the dyno if u dont believe me http://youtube.com/watch?v=yIhsv6WSboY

thanks for that link. whp is all that matters...where the rubber meets the road. that gtr put down 431 whp, and 425 wtq.

the z06 put down 443 whp and 411 wtq on lg motorsports' dyno...i know it's a different dyno, different day. http://www.z06vette.com/forums/f64/z...numbers-88326/ the torque management plus lack of traction kills the 0-60 time...but you only do 0-60 once in a race.

the zr1 should dyno above 540 whp. the gtr isn't even close! but i don't think it's the hp, or wide tires that makes the gtr move around the 'ring. they just have a torsionally stiff frame, and well sorted out suspension that uses the tires better than the corvette's suspension.

you also have to consider the gear ratios. dyno runs are made in 4th gear, or close to 1:1. the z06 has a 9.10:1 overall first gear while the gtr has a 15.02:1 first. that gives the gtr a 57% higher lever advantage than the z06. i.e. 15.02*431 whp = 6474 whp vs 9.10*443 whp = 4031 whp. so i don't think the gtr is way overrated, just geared well for good 0-60 times. the twin-clutch tranny also helps 0-60.

you can see the gear advantage in 0-60, but the z06 pulls away above that. 1/4 mile mph is an indicator of hp, while e.t. is closely related to traction. the z06 traps at 123.7 mph, while the gtr traps at 116.5 mph. the gtr is going about as fast as it can given its power, while the z06 should be trapping 11.0. some stock z06 have gone high 10 seconds with stickier tires.

tvs is still a positive displacement supercharger. screw s/c compress the air - that's why blowers will never be as fast, or as strong as a screw s/c - and make higher boost way more efficiently - around 90%. i'd go with kenne bell vs whipple ftw. kenne uses larger diameter rotors = more efficient, slower speed, less parasitic loss. he has 7 psi kits for the ls6 that will walk all over the zr1.

intake length tuning abosolutely DOES help s/c engines...just as header tuning helps turbos. just because they can make the intake that way doesn't mean it's optimal. i guarantee gmpt had to use a psi or two more to get the cylinder filling at high rpm because they lost the ram effect from super short runners.

[epaulo]

Originally Posted by ogg vorbis

thanks for that link. whp is all that matters...where the rubber meets the road. that gtr put down 431 whp, and 425 wtq.

the z06 put down 443 whp and 411 wtq on lg motorsports' dyno...i know it's a different dyno, different day. http://www.z06vette.com/forums/f64/z...numbers-88326/ the torque management plus lack of traction kills the 0-60 time...but you only do 0-60 once in a race.

the zr1 should dyno above 540 whp. the gtr isn't even close! but i don't think it's the hp, or wide tires that makes the gtr move around the 'ring. they just have a torsionally stiff frame, and well sorted out suspension that uses the tires better than the corvette's suspension.

you also have to consider the gear ratios. dyno runs are made in 4th gear, or close to 1:1. the z06 has a 9.10:1 overall first gear while the gtr has a 15.02:1 first. that gives the gtr a 57% higher lever advantage than the z06. i.e. 15.02*431 whp = 6474 whp vs 9.10*443 whp = 4031 whp. so i don't think the gtr is way overrated, just geared well for good 0-60 times. the twin-clutch tranny also helps 0-60.

you can see the gear advantage in 0-60, but the z06 pulls away above that. 1/4 mile mph is an indicator of hp, while e.t. is closely related to traction. the z06 traps at 123.7 mph, while the gtr traps at 116.5 mph. the gtr is going about as fast as it can given its power, while the z06 should be trapping 11.0. some stock z06 have gone high 10 seconds with stickier tires.

tvs is still a positive displacement supercharger. screw s/c compress the air - that's why blowers will never be as fast, or as strong as a screw s/c - and make higher boost way more efficiently - around 90%. i'd go with kenne bell vs whipple ftw. kenne uses larger diameter rotors = more efficient, slower speed, less parasitic loss. he has 7 psi kits for the ls6 that will walk all over the zr1.

intake length tuning abosolutely DOES help s/c engines...just as header tuning helps turbos. just because they can make the intake that way doesn't mean it's optimal. i guarantee gmpt had to use a psi or two more to get the cylinder filling at high rpm because they lost the ram effect from super short runners.

didnt say it was over rated i said under-rated as its pushing more power then they claim. and yes i realize that the GTR has a great structure, thus producing very minimal body roll, suspension and drivetrain on the car is awsome, and handles and transfers the power with ease.

if the car was only producing the claimed 480hp and 430tq, givin its curb weight, there is no way it would compete with the porsche and Z06, doesnt matter how great the suspension and drivetrain is. look at the 911, 480hp 460tq, significantly lighter than the gtr, and its imo equal to the Z06. so ur saying a car with less torque and more weight will out perform the 911? which is an extremly balanced vehicle. sorry numbers just dont seem right, only way the gtr can compete is if its pushing out well more then 500hp and tq given its weight disadvantage.

[ogg vorbis]

i know i had a m90. an m112 has the same rotor diameter, but longer rotors. it flows ~20% more at the same efficiency - 62% peak.

an interesting note, the lsa tvs1900 has a peak adiabatic efficiency of 73%. i took the map from eaton's page http://www.eaton.com/EatonCom/Produc.../TVS/index.htm, and converted m^3/hr to lb/min (multiply by 0.0406). it has >70% from 5000-14000 rpm (19-60 lb/min). it looks like it will flow up to 16000 rpm, pr of 2.2 (18 psi), and 70 lb/min (about 760 bhp).

will zr1 owners want way more power than stock? yes. can they just drop on an aftermarket s/c? no. will the tvs give more power with a smaller pulley? possibly up to 900 bhp. i don't know the rotor rpm/pulley ratio at peak hp, so i can't figure an ideal pulley diameter. the injectors are too small for e85 even with the stock pulley - the zr1 isn't flex fuel. 85# injectors, e85, and smaller pulley should get you there.

to help lauch the zr1, a centrifugal s/c may have been a better choice than the tvs, or turbo. i'd still really love to see an auto tranny that locks the tc through every gear. it holds tonnes of power, and is probably as efficient as a manual (albeit 90 lb heavier).

[ogg vorbis]

Originally Posted by epaulo

sorry numbers just dont seem right, only way the gtr can compete is if its pushing out well more then 500hp and tq given its weight disadvantage.

ice don't make enough torque to get a car moving with 1:1 gearing. gearing multiplies power. the gtr uses more gear multiplication, so that it in fact has a better power/weight ratio than either the porsche or z06. if this analysis doesn't make sense to you, just take an automotive engineer's word at face value.

here are the final drive ratios:
......gtr...z06...911
1st 15.02 9.10 13.14
2nd 8.51 6.09 7.36
3rd 5.88 4.45 5.09
4th 4.63 3.42 4.06

here's available hp in each gear:
......gtr...z06...911
1st 7210 4596 6307
2nd 4085 3075 3533
3rd 2822 2247 2443
4th 2222 1727 1949

the test weight of the gtr, z06 and 911 are 3960 lb, 3350 lb, and 3710 lb, respectively. power to weight ratio in 1st gear is 1.82 hp/lb, 1.37 hp/lb, and 1.7 hp/lb. power/weight in 3rd gear is 0.71 hp/lb, 0.67 hp/lb, and 0.66 hp/lb. the gtr, despite having slightly lower peak hp, has more hp at the wheels in first gear, and this is why it accelerates faster than mere figures would show. i hope this helps.

fwiw, an ls3 c6 z51 with 3.70:1 dif will come very close to the z06 in 0-60. 3.70 over stock 3.42 gearing gives 8.2% more power (not engine power, power at the wheels!) since the ls3 puts down 394 whp, this would give 426 whp, or a 30 whp gain.

[epaulo]

Originally Posted by ogg vorbis

ice don't make enough torque to get a car moving with 1:1 gearing. gearing multiplies power. the gtr uses more gear multiplication, so that it in fact has a better power/weight ratio than either the porsche or z06. if this analysis doesn't make sense to you, just take an automotive engineer's word at face value.

here are the final drive ratios:
......gtr...z06...911
1st 15.02 9.10 13.14
2nd 8.51 6.09 7.36
3rd 5.88 4.45 5.09
4th 4.63 3.42 4.06

here's available hp in each gear:
......gtr...z06...911
1st 7210 4596 6307
2nd 4085 3075 3533
3rd 2822 2247 2443
4th 2222 1727 1949

the test weight of the gtr, z06 and 911 are 3960 lb, 3350 lb, and 3710 lb, respectively. power to weight ratio in 1st gear is 1.82 hp/lb, 1.37 hp/lb, and 1.7 hp/lb. power/weight in 3rd gear is 0.71 hp/lb, 0.67 hp/lb, and 0.66 hp/lb. the gtr, despite having slightly lower peak hp, has more hp at the wheels in first gear, and this is why it accelerates faster than mere figures would show. i hope this helps.

fwiw, an ls3 c6 z51 with 3.70:1 dif will come very close to the z06 in 0-60. 3.70 over stock 3.42 gearing gives 8.2% more power (not engine power, power at the wheels!) since the ls3 puts down 394 whp, this would give 426 whp, or a 30 whp gain.

i see i see, whats the FDR on the GTR?

[tamatt27]

Originally Posted by firefighter

Just a few things to clarify. Realy I'm not picking just saying. The Eaton on the GT was a Radix 112HH and the one on your GS was either a M62 or a M90 while the 112 is more efficient than either the 62 or the 90 they are all inefficient in comparoson to the TVS

The Radix 112 is a Magnacharger..not an Eaton.

[firefighter]

It's an Eaton as is all of Magnas S/C's.

http://www.eaton.com/EatonCom/Produc...M112/index.htm

[firefighter]

Also here.

http://www.magnusonproducts.com/models.htm

[epaulo]

Originally Posted by tamatt27

The Radix 112 is a Magnacharger..not an Eaton.

Eaton, eaton supplies magna and radix with the blowers,

[fish5225]

Originally Posted by ogg vorbis
by now you all know about the eaton tvs s/c. i'm disappointed with this engine. forg gt's regularly rip off the tvs and install a whipple...you can't do that with the ls9. installing a smaller pulley is a diminishing returns deal...i learned that from owning a supercharged buick gs. the intake manifold is horrendous. i also don't like the intake ports, and piston shape.

even magnuson is putting out ls crate motors with 800+ hp on premium gasoline. a kenne bell screw s/c with larger pulley makes more power on less boost, with less air heating, less parasitic loss. a pair of borg warner s258 turbos would have obviously kicked ass - 600+ whp on the same boost. early ls9 development used turbos, and were near 700 hp.

omg...the nissan gtr ran the 'ring in 7:29!! an overweight, nose-heavy, small-tired, lower powered car embarassed the zr1. the zr1 will obviously do well on the 'ring, but imo chevy better do lots more tuning before it goes on sale in september!

Dear Ogg: Your statements about the Kenny Bell are not factual according to all testing that has been done on the KB2.8 vs the TVS 2300. The TVS 2300, a smaller displacement blower(2300 vs 2800 for the KB) is actually more efficient at lower levels of boost, up to about 14psi. You are correct the screws become more efficient at higher levels of boost but no one is running a gas engine(diesil is different) at those levels from the factory.

The other advantage of the TVS design is that it has almost no parasitic loss until it is on boost. The screws design does not allow for this. I.E. better gas mileage when not under boost.

Both the screw and TVS are great systems but the TVS is smaller, easier to fit under a hood and it like the other magnacharger systems, reliability will be outstanding. All needs for a prodution car.

My suggestion, drive one, I bet you will be blown away.