Any N/A Lt-1's making 500 rwhp?
07-14-2005, 04:37 PM
#42
Le Mans Master
Originally Posted by aqualung
LT4POWR, I did not want to quote your very detailed and and well researched post, but how come all Camaros and T/A's and no Corvettes?
What's wrong with us Vette owners? Sounds to me like a lot of Z28's would be spankin our butts.
What's wrong with us Vette owners? Sounds to me like a lot of Z28's would be spankin our butts.
Also, most of the big $ corvette guys have moved into the C5 & C6. Can't really blame them...building 500rwhp NA LSx isn't too tough if you've got the $.
07-14-2005, 04:44 PM
#43
Safety Car
Originally Posted by aqualung
LT4POWR, I did not want to quote your very detailed and and well researched post, but how come all Camaros and T/A's and no Corvettes?
What's wrong with us Vette owners? Sounds to me like a lot of Z28's would be spankin our butts.
What's wrong with us Vette owners? Sounds to me like a lot of Z28's would be spankin our butts.
I can tell you from a technical point the IRS has somthing to do with it. The others are absolutly right that most of the Vett guys like to drive thier cars and don't build them for an all out race car with sevreal exeptions, plenty of 10 second cars on this board. Now with all that said I am scared to death of hooking up at the track and breaking my 44 in 1/2, seen it happen way to many times. It seems as soon as the 10's come, I am a long way from that BTW, the 44's are a ticking time bomb. Some make 100's of passes some make one but I dont trust the 44 in stock form. Now an auto car with a cryoed 44 can run in the 10's and have less problems with IRS but most of them have twisted a 1/2 shaft or 2.
07-14-2005, 04:52 PM
#44
Drifting
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St. Jude Donor '05
Originally Posted by Nathan Plemons
If you're looking for a drag only car it is easier to put a stronger drivetrain in an F-body and there will be less tears shed if you destroy the interior.I think building a F-body over a Y is logical just because you don't have to deal with all the extra BS that isn't really needed... like traction control, stablity controls, elaborate climate controls, electronic shocks, etc.
Now I know that a F-body will occasionally have traction control and not every vette has climate controls.. my point is there is still too much unneeded things weeded into the corvettes body.
Y's are more cadillac than they need to be for a race car.
07-19-2005, 10:13 AM
#46
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We have a 95 TA with a 355 that runs 10.70s all day long. It is a NHRA stock eliminator car which means its got unported LT1 heads, 48mm throttle body, stock compression and stock weight pistons and rods.
I say the heads are unported but in reality they have been acid ported so that they appear stock. But let me tell you acid porting in no way can replicate flow numbers that would even come close to a normal port job. Not to mention that we are stuck with a 48mm TB, which cannot be modified in any way because its just too easy to get busted by the NHRA tech boys
The power comes from the custom ground Bullet cam that we are running, and of course a extremely well setup chassis, gear and tranny setup. We use a TH350 with a 2.75 low gear, and a converter with approximately 5500 stall. The valve body is a electronic valve body that can be programmed to shift by RPM. It was legalized for stock class because in 94 and 95 the F body cars came with 4L60E transmissions, so a electronic shift is A OK
The engine dyno'd at less than 515 HP which means we have considerably less than 500 at the tires, but because of the chassis it is able to click off good times. So it isn't just about Hp that makes your car quick, it is a combination of power and chassis. You can have tons of power but if you can't get it to the ground or control it, you won't be very fast.
I say the heads are unported but in reality they have been acid ported so that they appear stock. But let me tell you acid porting in no way can replicate flow numbers that would even come close to a normal port job. Not to mention that we are stuck with a 48mm TB, which cannot be modified in any way because its just too easy to get busted by the NHRA tech boys
The power comes from the custom ground Bullet cam that we are running, and of course a extremely well setup chassis, gear and tranny setup. We use a TH350 with a 2.75 low gear, and a converter with approximately 5500 stall. The valve body is a electronic valve body that can be programmed to shift by RPM. It was legalized for stock class because in 94 and 95 the F body cars came with 4L60E transmissions, so a electronic shift is A OK
The engine dyno'd at less than 515 HP which means we have considerably less than 500 at the tires, but because of the chassis it is able to click off good times. So it isn't just about Hp that makes your car quick, it is a combination of power and chassis. You can have tons of power but if you can't get it to the ground or control it, you won't be very fast.
07-19-2005, 10:36 AM
#47
Originally Posted by tjwong
So it isn't just about Hp that makes your car quick, it is a combination of power and chassis. You can have tons of power but if you can't get it to the ground or control it, you won't be very fast.
The best race I've ever done is against a car that puts down some 40 HP less than me. He just happened to have a TH350, converter, and sticky tires. I could run him down on the big end but you're talking about a difference of .001 seconds!
07-19-2005, 12:15 PM
#48
Team Owner
Originally Posted by Nathan Plemons
500 / .85 = 588.24
500 /.8 = 625
That's if you believe that drivetrain loss is a linear relationship, which I really have a hard time believing that it it is. I'm not sure what type of scale it follows, but it can't be linear.
I mean think about it, an engine makes 300 HP on an engine dyno and it only makes 270 on the chassis dyno, that's 10% loss. Change nothing about the drivetrain but make the engine make 400 hp. If you still have 10% loss then you're looking at 360 HP to the wheels, acceptable I guess. Once it makes 500 though you're looking at 450 to the wheels.
That is a linear pattern, but after a while it just stops making sense. I mean if the engine made 1000 HP, why would the same drivetrain suddenly suck down 100 HP whereas it only took off 30 HP when it made 300 HP? Although a dimenishing efficiency is possible it isn't really all that likely for this kind of system. It seems like there would be an upper limit to the amount of power that your drivetrain would soak up.
This is why I find it nearly useless to try and compare CHP and RWHP numbers. Sticking with one or the other is just fine, but trying to compare them really can become apples to oranges really quickly.
500 /.8 = 625
That's if you believe that drivetrain loss is a linear relationship, which I really have a hard time believing that it it is. I'm not sure what type of scale it follows, but it can't be linear.
I mean think about it, an engine makes 300 HP on an engine dyno and it only makes 270 on the chassis dyno, that's 10% loss. Change nothing about the drivetrain but make the engine make 400 hp. If you still have 10% loss then you're looking at 360 HP to the wheels, acceptable I guess. Once it makes 500 though you're looking at 450 to the wheels.
That is a linear pattern, but after a while it just stops making sense. I mean if the engine made 1000 HP, why would the same drivetrain suddenly suck down 100 HP whereas it only took off 30 HP when it made 300 HP? Although a dimenishing efficiency is possible it isn't really all that likely for this kind of system. It seems like there would be an upper limit to the amount of power that your drivetrain would soak up.
This is why I find it nearly useless to try and compare CHP and RWHP numbers. Sticking with one or the other is just fine, but trying to compare them really can become apples to oranges really quickly.
HP Thread
07-19-2005, 01:24 PM
#49
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Let's be realistic:
A normally-aspirated 383 making well over 500chp is not a street engine. Of course, it can be done....
But, do you want to live with it on the street?
We ALL have big dreams.
Larry
code5coupe
A normally-aspirated 383 making well over 500chp is not a street engine. Of course, it can be done....
But, do you want to live with it on the street?
We ALL have big dreams.
Larry
code5coupe
07-19-2005, 01:56 PM
#50
Team Owner
To be honest, that's getting into NASCAR power outputs. Busch cars are doing 500hp from 358ci... I just don't see how a 383 would do it and still be streetable...
Several years ago, LPE built a 427ci SBC for Car & Driver. It was installed in a 1995 Vette.
Interesting motor. The block was based on a NASCAR Gen II racing block, it was the only one that LPE felt they could expand to 427ci and not break it.
It had a custom plenum and ignition system. Whether it was smog legal is another question, but it would past most states, except CA, I am sure.
The engine put out 600hp, but cost $50,000.00 to build!!!!
Several years ago, LPE built a 427ci SBC for Car & Driver. It was installed in a 1995 Vette.
Interesting motor. The block was based on a NASCAR Gen II racing block, it was the only one that LPE felt they could expand to 427ci and not break it.
It had a custom plenum and ignition system. Whether it was smog legal is another question, but it would past most states, except CA, I am sure.
The engine put out 600hp, but cost $50,000.00 to build!!!!
07-19-2005, 06:32 PM
#51
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The biggest hindrance to getting 500 rwhp out of a LTx car appears to be the intake.
I’m currently making 460 rwhp with a 12.4 to 1 compression 398ci motor using a 246/248-.615 lift hydraulic cam. Didn’t want to go the solid lifter route as I had ruined a couple of engines breaking solid lifters driving the car on the street.
To get the 460 rwhp the car has about everything possible you can do to one including friction/thermo coatings, ultra lightweight forged powder rods, custom lightweight Lunati pistons, etc. etc. It pulls 450 rwhp at only 5600 rpm and still makes about 430 rwhp at 7200 rpm so the powerband is very useful but indicates more is in the car.
It’s got Trick Flow heads that flow 260 cfm @ only .400 lift and 300cfm @ .600 using 2.08/1.625 valves. Exhaust flow is in the 225 range so these pretty stout heads as the flow numbers are legit.I’ve flowed several sets of heads at Lloyds Elliots and virtually none flow what the person whom ported them said they did.
I could of gotten more flow on at higher lift levels but at the expense of low lift levels. Not much into peak numbers but more into average flow within the lift of the cam. Being it's a street driven car, I didn't want to go much more than .630 max.
The intake is a LT4 that was welded on the outside and ported gasket matched to raised runner off road LT4 gaskets and even with such extensive work and a monoblade, it starts to pull 2 psi vacuum on the upper rpm range.
I’m in Texas and 100 degree summer is no time to try and set any hp records but as soon as the weather turns cooler we are going to put it back on the dyno and see if we can find a bit more power. Being the intake appears to be the problem, if we can’t figure out something else I going to go with a sheet metal intake.
500 rwhp using 23 degree head reverse cooling technology???………. Possible sure, how much money do you have as I’ve dumped a ton in mine already and not there.
FYI……… I was physically there when Jordon Musser dynoed making the 471 rwhp using a similar cam grind only it was solid lifter. Jordon ported his own AFR heads with a little bit of technical help. That’s the most from home ported heads I’ve ever head of and kudo’s are in order to Jordon.
Denny
I’m currently making 460 rwhp with a 12.4 to 1 compression 398ci motor using a 246/248-.615 lift hydraulic cam. Didn’t want to go the solid lifter route as I had ruined a couple of engines breaking solid lifters driving the car on the street.
To get the 460 rwhp the car has about everything possible you can do to one including friction/thermo coatings, ultra lightweight forged powder rods, custom lightweight Lunati pistons, etc. etc. It pulls 450 rwhp at only 5600 rpm and still makes about 430 rwhp at 7200 rpm so the powerband is very useful but indicates more is in the car.
It’s got Trick Flow heads that flow 260 cfm @ only .400 lift and 300cfm @ .600 using 2.08/1.625 valves. Exhaust flow is in the 225 range so these pretty stout heads as the flow numbers are legit.I’ve flowed several sets of heads at Lloyds Elliots and virtually none flow what the person whom ported them said they did.
I could of gotten more flow on at higher lift levels but at the expense of low lift levels. Not much into peak numbers but more into average flow within the lift of the cam. Being it's a street driven car, I didn't want to go much more than .630 max.
The intake is a LT4 that was welded on the outside and ported gasket matched to raised runner off road LT4 gaskets and even with such extensive work and a monoblade, it starts to pull 2 psi vacuum on the upper rpm range.
I’m in Texas and 100 degree summer is no time to try and set any hp records but as soon as the weather turns cooler we are going to put it back on the dyno and see if we can find a bit more power. Being the intake appears to be the problem, if we can’t figure out something else I going to go with a sheet metal intake.
500 rwhp using 23 degree head reverse cooling technology???………. Possible sure, how much money do you have as I’ve dumped a ton in mine already and not there.
FYI……… I was physically there when Jordon Musser dynoed making the 471 rwhp using a similar cam grind only it was solid lifter. Jordon ported his own AFR heads with a little bit of technical help. That’s the most from home ported heads I’ve ever head of and kudo’s are in order to Jordon.
Denny
07-19-2005, 08:24 PM
#53
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Originally Posted by d48mclain
The biggest hindrance to getting 500 rwhp out of a LTx car appears to be the intake.
...
I’m in Texas and 100 degree summer is no time to try and set any hp records but as soon as the weather turns cooler we are going to put it back on the dyno and see if we can find a bit more power. Being the intake appears to be the problem, if we can’t figure out something else I going to go with a sheet metal intake.
Denny
...
I’m in Texas and 100 degree summer is no time to try and set any hp records but as soon as the weather turns cooler we are going to put it back on the dyno and see if we can find a bit more power. Being the intake appears to be the problem, if we can’t figure out something else I going to go with a sheet metal intake.
Denny
http://www.kinsler.com/i_manifolds.htm
You can set these up to run with the stock computer. You need to run vacuum lines from each runner to a block, and then to the vacuum sensor.
07-20-2005, 03:00 AM
#54
Drifting
Tanner does drive the Z on the street. He actually drove it over the border to the dream cruise. He did dyno the car and got around 450 this was with weak valve springs but right around the time he ran the 10.58. The run was done with a ported LT1 intake.
He now has a hogan sheet metal intake. He said that the front plugs would read as a lean burn and the rear plugs would read pig rich. So he swithced to the sheet metal intake. The plugs look alot better now.
If you guys want to see some of the F-body big dogs in action, you should come out to the M10 event.
http://www.migmevent.com/m10/
He now has a hogan sheet metal intake. He said that the front plugs would read as a lean burn and the rear plugs would read pig rich. So he swithced to the sheet metal intake. The plugs look alot better now.
If you guys want to see some of the F-body big dogs in action, you should come out to the M10 event.
http://www.migmevent.com/m10/
07-20-2005, 04:45 AM
#55
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St. Jude Donor '03 & '05
Originally Posted by Bruce
there is only one that known to some forum members. I have seen the car in person. That was a 1993 coupe auto 401ci LT1 AFR 220 12.6 c/r solid roller 242/242 @ .05 620 lift. Yes it ran on pump gas and that car were driving to work daily. Ran 10.6 @ 126mph and dyno exactly 500rwhp. Phil LT401 used to post here. But he has not post here anu more, Don't know why.
Bruce
Bruce
http://phil.tobin.net/Hoover/
I ran one day with him at Rockingham, years ago. IMPRESSIVE. Idled really well for the power it was making, and I think he drove it 700 miles a week.
07-20-2005, 04:18 PM
#56
Melting Slicks
if tobin can do it and freely posts the parts he used to do it some odd years ago i dont know why more ppl cant do it now. technology hasnt grown that much for LTx parts but im sure its grown a little. I would think the AFR 227 heads would be the place to start those flow more than any other head i have seen for the LTx motors. a 1300cfm monoblade throttle body and 1 7/8 inch headers would probably be in order as well. if you want to make over 500rwhp NA you need to think top end power. and that means flow. and lots of it. you are probably going to need god awful big injectors to be able to match enough fuel to all that air you are going to push. not sure what kind of cam you would need but would probably want one that revs close to 7k to get that peak power you are looking for. 12.0:1 compression will likely be close to what you need. which means no revving much over 5k on the street with 93 octane. what else? you need as many of your moving parts to be as lightweight as possible. a lightweight clutch would be a must i imagine. portmatching on everything is obvious. i dont know how strong titanium valves are but you might want to look into them. you need a completely forged bottom end to deal with all that compression. i wouldnt even try with a 383. i would go in the 396-406 range since thats as high as you can go with an LTx i think. u probably would have to go with a pretty open 3 inch exhaust. i would call AFR and see what kind of cam they would reccomend with their 227 heads for max top end power. I am interested in this as well because someday down the road, i too would like to make close to 500rwhp NA with a stroker motor. let me know what you all think of this
07-20-2005, 04:59 PM
#57
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Originally Posted by 1996man
i too would like to make close to 500rwhp NA with a stroker motor. let me know what you all think of this
Choose one:
A) I think it would be most cost-effective to put the money towards a 2006 Z06.
B) I think you'd better hit the lottery before you start.
....just ask anyone who's done it/tried to do it.
Rock on and good luck to ya'.
Larry
code5coupe
07-20-2005, 06:20 PM
#58
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St. Jude Donor '03 & '05
Phil did post the parts, and I think he was running a 401. But it was tuned very well. Goes to his website, as there are parts etc and videos.
http://phil.tobin.net/Hoover/top.html
http://phil.tobin.net/Hoover/top.html
Originally Posted by 1996man
if tobin can do it and freely posts the parts he used to do it some odd years ago i dont know why more ppl cant do it now. technology hasnt grown that much for LTx parts but im sure its grown a little. I would think the AFR 227 heads would be the place to start those flow more than any other head i have seen for the LTx motors. a 1300cfm monoblade throttle body and 1 7/8 inch headers would probably be in order as well. if you want to make over 500rwhp NA you need to think top end power. and that means flow. and lots of it. you are probably going to need god awful big injectors to be able to match enough fuel to all that air you are going to push. not sure what kind of cam you would need but would probably want one that revs close to 7k to get that peak power you are looking for. 12.0:1 compression will likely be close to what you need. which means no revving much over 5k on the street with 93 octane. what else? you need as many of your moving parts to be as lightweight as possible. a lightweight clutch would be a must i imagine. portmatching on everything is obvious. i dont know how strong titanium valves are but you might want to look into them. you need a completely forged bottom end to deal with all that compression. i wouldnt even try with a 383. i would go in the 396-406 range since thats as high as you can go with an LTx i think. u probably would have to go with a pretty open 3 inch exhaust. i would call AFR and see what kind of cam they would reccomend with their 227 heads for max top end power. I am interested in this as well because someday down the road, i too would like to make close to 500rwhp NA with a stroker motor. let me know what you all think of this
Last edited by steve40th; 07-20-2005 at 06:24 PM.
07-20-2005, 08:13 PM
#59
Melting Slicks
ive been to his site many times. he is running a monoblade throttle body which is indeed a 1300cfm i beleive but hes not using the ported AFR227 heads which flow over 309 CFM i think and hes only using 1 3/4 inch headers. Im surprised he is only running 36lb injectors. this is by no means bad. in fact he should receive even more praise for getting that power out of those parts. just makes me wonder what you could do with better parts that are available
07-20-2005, 08:15 PM
#60
Melting Slicks
Originally Posted by rocco16
Choose one:
A) I think it would be most cost-effective to put the money towards a 2006 Z06.
B) I think you'd better hit the lottery before you start.
....just ask anyone who's done it/tried to do it.
Rock on and good luck to ya'.
Larry
code5coupe
A) I think it would be most cost-effective to put the money towards a 2006 Z06.
B) I think you'd better hit the lottery before you start.
....just ask anyone who's done it/tried to do it.
Rock on and good luck to ya'.
Larry
code5coupe