Highest Project Power output from 5.0L normally Aspirated
06-03-2005, 03:49 PM
#1
Race Director
Thread Starter
Highest Project Power output from 5.0L normally Aspirated
Assuming a 5.0 Limit what is peak normally aspratad hp levels can 928 based motor achieve?
Reason I am asking is and considering submitting rule change for PCA club racing basicly moving 3.0 944/968's to GT4, 2.5&2.7L 944 to GT5. My arguement is based the fact that teh inline 4 cyl motors don't have same power output potential as the flat 6's and 4s of similar displacement.
What are the thoughs on GT2 928's. Do they routinely make enough hp for the class? Or would 5.0L and under 928 do better in GT3 leaving GT2 for stoker 928's GTS motors?
Reason I am asking is and considering submitting rule change for PCA club racing basicly moving 3.0 944/968's to GT4, 2.5&2.7L 944 to GT5. My arguement is based the fact that teh inline 4 cyl motors don't have same power output potential as the flat 6's and 4s of similar displacement.
What are the thoughs on GT2 928's. Do they routinely make enough hp for the class? Or would 5.0L and under 928 do better in GT3 leaving GT2 for stoker 928's GTS motors?
06-03-2005, 05:45 PM
#2
Rennlist Member
truely , PCA/POC has their heads up their A&&es when it comes to the 928. they forget one MAJOR factor about racing in that its not only hp to weight ratios, although thats fine for the same types of cars, but Asolute weight!!! Absolute weight effects two other factors EQUAL in importance in racing or timetrialing (ie BRAKING and Cornering) did these guys forget or never learn ANYTHING about why cars do the things they do on the track?
anyway, Truely, as ive seen it, a 928 is a GT3 to GT4 class car. regularly, a 928 with as much hp that can be possibly put to the wheels out of a stock engine, even add 10%, would be 5 seconds behind a good GT3-4 car. (ie laguna seca Anderson runs 1:35 on slicks, and so do GT3 and GT4 cars.)
anderson runs the 6.5 liter engine. PCA rules stop at greater than 3.4 liters and then turbo/engine size and there is no limit on weight. However, there is in the stock/production classes and then the weight should be a factor, but it isnt. it isnt because with the 911s, they all are in the same ball park. the 928 with its stock leather ceilings, dual AC and sound insulation galore, is sometimes 1000lbs heavier than a similarly prepared 911.
in the time trial groups, the 928 should move up a class if it is a non GT/GTS car. In POC, why do they think a porsche 996 with 320hp and and weight of 2950lbs and 20 year newer technlogy, should run with a 928 with 500lbs greater weight and smaller tires!!!!!!!! its just plain stupid and its a clear indication that PCA doesnt want to let the 928 play any of the racing games fairly. you may come back with porsche 944 turbo?? but folks, again, look at the weights and the mods allowed. braking and handling are a main funtion of weight. our 928s are wider and can be better balanced, but its not as much as a factor as the absolute weight.
use this argument and see if someone with PCA can open their eyes.
MK
anyway, Truely, as ive seen it, a 928 is a GT3 to GT4 class car. regularly, a 928 with as much hp that can be possibly put to the wheels out of a stock engine, even add 10%, would be 5 seconds behind a good GT3-4 car. (ie laguna seca Anderson runs 1:35 on slicks, and so do GT3 and GT4 cars.)
anderson runs the 6.5 liter engine. PCA rules stop at greater than 3.4 liters and then turbo/engine size and there is no limit on weight. However, there is in the stock/production classes and then the weight should be a factor, but it isnt. it isnt because with the 911s, they all are in the same ball park. the 928 with its stock leather ceilings, dual AC and sound insulation galore, is sometimes 1000lbs heavier than a similarly prepared 911.
in the time trial groups, the 928 should move up a class if it is a non GT/GTS car. In POC, why do they think a porsche 996 with 320hp and and weight of 2950lbs and 20 year newer technlogy, should run with a 928 with 500lbs greater weight and smaller tires!!!!!!!! its just plain stupid and its a clear indication that PCA doesnt want to let the 928 play any of the racing games fairly. you may come back with porsche 944 turbo?? but folks, again, look at the weights and the mods allowed. braking and handling are a main funtion of weight. our 928s are wider and can be better balanced, but its not as much as a factor as the absolute weight.
use this argument and see if someone with PCA can open their eyes.
MK
Originally Posted by M758
Assuming a 5.0 Limit what is peak normally aspratad hp levels can 928 based motor achieve?
Reason I am asking is and considering submitting rule change for PCA club racing basicly moving 3.0 944/968's to GT4, 2.5&2.7L 944 to GT5. My arguement is based the fact that teh inline 4 cyl motors don't have same power output potential as the flat 6's and 4s of similar displacement.
What are the thoughs on GT2 928's. Do they routinely make enough hp for the class? Or would 5.0L and under 928 do better in GT3 leaving GT2 for stoker 928's GTS motors?
Reason I am asking is and considering submitting rule change for PCA club racing basicly moving 3.0 944/968's to GT4, 2.5&2.7L 944 to GT5. My arguement is based the fact that teh inline 4 cyl motors don't have same power output potential as the flat 6's and 4s of similar displacement.
What are the thoughs on GT2 928's. Do they routinely make enough hp for the class? Or would 5.0L and under 928 do better in GT3 leaving GT2 for stoker 928's GTS motors?
06-03-2005, 05:53 PM
#3
USMarine
Rennlist Member
Rennlist Member
Originally Posted by mark kibort
truely , PCA/POC has their heads up their A&&es when it comes to the 928. they forget one MAJOR factor about racing in that its not only hp to weight ratios, although thats fine for the same types of cars, but Asolute weight!!! Absolute weight effects two other factors EQUAL in importance in racing or timetrialing (ie BRAKING and Cornering) did these guys forget or never learn ANYTHING about why cars do the things they do on the track?
anyway, Truely, as ive seen it, a 928 is a GT3 to GT4 class car. regularly, a 928 with as much hp that can be possibly put to the wheels out of a stock engine, even add 10%, would be 5 seconds behind a good GT3-4 car. (ie laguna seca Anderson runs 1:35 on slicks, and so do GT3 and GT4 cars.)
anderson runs the 6.5 liter engine. PCA rules stop at greater than 3.4 liters and then turbo/engine size and there is no limit on weight. However, there is in the stock/production classes and then the weight should be a factor, but it isnt. it isnt because with the 911s, they all are in the same ball park. the 928 with its stock leather ceilings, dual AC and sound insulation galore, is sometimes 1000lbs heavier than a similarly prepared 911.
in the time trial groups, the 928 should move up a class if it is a non GT/GTS car. In POC, why do they think a porsche 996 with 320hp and and weight of 2950lbs and 20 year newer technlogy, should run with a 928 with 500lbs greater weight and smaller tires!!!!!!!! its just plain stupid and its a clear indication that PCA doesnt want to let the 928 play any of the racing games fairly. you may come back with porsche 944 turbo?? but folks, again, look at the weights and the mods allowed. braking and handling are a main funtion of weight. our 928s are wider and can be better balanced, but its not as much as a factor as the absolute weight.
use this argument and see if someone with PCA can open their eyes.
MK
anyway, Truely, as ive seen it, a 928 is a GT3 to GT4 class car. regularly, a 928 with as much hp that can be possibly put to the wheels out of a stock engine, even add 10%, would be 5 seconds behind a good GT3-4 car. (ie laguna seca Anderson runs 1:35 on slicks, and so do GT3 and GT4 cars.)
anderson runs the 6.5 liter engine. PCA rules stop at greater than 3.4 liters and then turbo/engine size and there is no limit on weight. However, there is in the stock/production classes and then the weight should be a factor, but it isnt. it isnt because with the 911s, they all are in the same ball park. the 928 with its stock leather ceilings, dual AC and sound insulation galore, is sometimes 1000lbs heavier than a similarly prepared 911.
in the time trial groups, the 928 should move up a class if it is a non GT/GTS car. In POC, why do they think a porsche 996 with 320hp and and weight of 2950lbs and 20 year newer technlogy, should run with a 928 with 500lbs greater weight and smaller tires!!!!!!!! its just plain stupid and its a clear indication that PCA doesnt want to let the 928 play any of the racing games fairly. you may come back with porsche 944 turbo?? but folks, again, look at the weights and the mods allowed. braking and handling are a main funtion of weight. our 928s are wider and can be better balanced, but its not as much as a factor as the absolute weight.
use this argument and see if someone with PCA can open their eyes.
MK
06-03-2005, 06:12 PM
#4
Race Director
Thread Starter
So mark... Do where do you think GT 928's should be placed?
5.0L and under in GT3 over 5.0L in GT2.
Or
under 5.0L in GT4, and over 5.0 GT3
You saw my proposal in the racing forum on trying to move normally aspriated 944 based cars basicly down 1 GT class and about the 10% weight reduction in "stock" groups. I don't know enough about the 928 to know where it really belongs. I am inclined to believe that in GT3 a 944 Turbo strong car. They make anywhere from 300 whp to 400 whp in most cases. Weights are often 2300 to 2400 or more. I figure that if a 928 S4 can pump out 326 fwhp stock then I'd guess that 350 to 400 at rear wheels would not be too bad for worked over motor.
Your car is what 2700lbs. So that is giving up some 300 to 400 lbs vs a 951. However your car still has steel fenders & stock glass. So I doubt the weght difference between a stripped & ligthened 951 and stripped and lightend 928 would be maybe 200 lbs?
I really don't think a 5.0 928 S4 in GT4 is good thing since it starts with more hp than the benchmark for the class which is the 2000 lbs 280-300 hp 2.8L 911 or 914. Sure it may also weight 700 lbs more, but it has some 30 hp edge with stock motor. May be the 4.7L 928 would be ok in GT4. Especially if the rules are change to allow 3.0L 944/968's in GT4.
So what is lightest 928 race car around? I know the lightest 944 NA I have seen was 2166 lbs. It carried a 968 motor. My 944 spec is 2400 lbs without resorting to fiberglass or lexan. Many 951's are 2300 and up even with with lexan and fiberglass. I remeber Rich A's white 79 928 being 2600 lbs or something. It is stripped, lexan, but still has steel body panels.
One other issue however is the 944 with 928 motor swap. Right now that is rare and expensive, but if you allow a 5.0L V8 in a 968 body shell you have very differently competitive car vs that same motor in 928 body shell. PCA club race rule currently only have displacement limits so that might open a new can of worms if V8's are classes better than inline 4's. Remember I have never seen a 944 motor in a 911 or 914 and don't think I would expect to see one either.
5.0L and under in GT3 over 5.0L in GT2.
Or
under 5.0L in GT4, and over 5.0 GT3
You saw my proposal in the racing forum on trying to move normally aspriated 944 based cars basicly down 1 GT class and about the 10% weight reduction in "stock" groups. I don't know enough about the 928 to know where it really belongs. I am inclined to believe that in GT3 a 944 Turbo strong car. They make anywhere from 300 whp to 400 whp in most cases. Weights are often 2300 to 2400 or more. I figure that if a 928 S4 can pump out 326 fwhp stock then I'd guess that 350 to 400 at rear wheels would not be too bad for worked over motor.
Your car is what 2700lbs. So that is giving up some 300 to 400 lbs vs a 951. However your car still has steel fenders & stock glass. So I doubt the weght difference between a stripped & ligthened 951 and stripped and lightend 928 would be maybe 200 lbs?
I really don't think a 5.0 928 S4 in GT4 is good thing since it starts with more hp than the benchmark for the class which is the 2000 lbs 280-300 hp 2.8L 911 or 914. Sure it may also weight 700 lbs more, but it has some 30 hp edge with stock motor. May be the 4.7L 928 would be ok in GT4. Especially if the rules are change to allow 3.0L 944/968's in GT4.
So what is lightest 928 race car around? I know the lightest 944 NA I have seen was 2166 lbs. It carried a 968 motor. My 944 spec is 2400 lbs without resorting to fiberglass or lexan. Many 951's are 2300 and up even with with lexan and fiberglass. I remeber Rich A's white 79 928 being 2600 lbs or something. It is stripped, lexan, but still has steel body panels.
One other issue however is the 944 with 928 motor swap. Right now that is rare and expensive, but if you allow a 5.0L V8 in a 968 body shell you have very differently competitive car vs that same motor in 928 body shell. PCA club race rule currently only have displacement limits so that might open a new can of worms if V8's are classes better than inline 4's. Remember I have never seen a 944 motor in a 911 or 914 and don't think I would expect to see one either.
06-03-2005, 06:44 PM
#5
Rennlist Member
I think those are fine ideas.
greater than 5.0 in GT3 lower than 5 liter in GT4
remember the weight is more important than the HP to weight ratios for the reasons ive listed.
the 928 doesnt have steel body panels. ALL Aluminum!!! (fenders, hood, doors, stock!) yes, mine is gutted and cut and is in the 2700lb range. with a safer cage and other things most top runners are running as far as safety equip, probably more like 2800. compared to a 2200lb car or 2400lbs that is HUGE. imagine carrying 2 big guys in a car with the same hp to weight. think you will have a CHANCE in the brake zones or around corners???
most prep'ed 944turbos have 330 to 360 rear wheel hp and are in the 2400lb range. Even in POC, this kind of power output is classed in R5 and can weigh 2880lbs while the 5 liter 928 has to weigh 3500lbs!!! not really a fair battle, although ive been known to put up a fight, its not fun carrying the weight .
the most a 5 liter has put out by most anyone is in the 330 to 350 hp range
at the rears. the 6.5 liter generally puts out 400 at the rear wheels with some tweeking, and its not until you put on all the new trick CF intake stuff, do you get 485hp at the rear wheels out of the 6.5 liter. those cars barely keep up with a new cup car with close driver abilities. (see Brent martini vs Anderson at road America last year. Or laguna seca, sears point, etc etc)
the lightest 928 around is mark andersons, and he has had the car COMPLETLEY remanufactured from the unibody sand blasted to remove weight and parts cut out that are not needed for structure, and then tubed for stifness. not much more to pull out. he is in the 2550lb range. regularly, you see 911s with 330flywheel hp 993 engines, weighing close to 2100lbs. in andersons class, thats a decent battle of cat an mouse (turns vs straights) any more hp out of a 911, and there is nothing the big hp vs the weight can buy you! they are different cars and the battles on different tracks can turn out different and thats how it should be.
based on times though, GT3 and GT4 are much faster than any similarly prepared 928 can run with its stockish engine and weight limit. the only way to compete with a 928 is a massive 130% upgrade in engine size, and thats borderline, not even porsche!
out at laguna, ive spun times actally faster than anderson when he came out to Laguna seca in 1999 in speedvision, with a car that is 100hp less than he had and lots less on the chassis as well. that 1:40.2 barely buys me a top 3 finish with the PCA GT4 class. however, with slicks knock a second or two off the time and its still 3 seconds off the winning GT3-4 times .
we have so much data with good drivers running all the tracks, that its silly not to face the reality and close the gaps for some fair competing.
MK
greater than 5.0 in GT3 lower than 5 liter in GT4
remember the weight is more important than the HP to weight ratios for the reasons ive listed.
the 928 doesnt have steel body panels. ALL Aluminum!!! (fenders, hood, doors, stock!) yes, mine is gutted and cut and is in the 2700lb range. with a safer cage and other things most top runners are running as far as safety equip, probably more like 2800. compared to a 2200lb car or 2400lbs that is HUGE. imagine carrying 2 big guys in a car with the same hp to weight. think you will have a CHANCE in the brake zones or around corners???
most prep'ed 944turbos have 330 to 360 rear wheel hp and are in the 2400lb range. Even in POC, this kind of power output is classed in R5 and can weigh 2880lbs while the 5 liter 928 has to weigh 3500lbs!!! not really a fair battle, although ive been known to put up a fight, its not fun carrying the weight .
the most a 5 liter has put out by most anyone is in the 330 to 350 hp range
at the rears. the 6.5 liter generally puts out 400 at the rear wheels with some tweeking, and its not until you put on all the new trick CF intake stuff, do you get 485hp at the rear wheels out of the 6.5 liter. those cars barely keep up with a new cup car with close driver abilities. (see Brent martini vs Anderson at road America last year. Or laguna seca, sears point, etc etc)
the lightest 928 around is mark andersons, and he has had the car COMPLETLEY remanufactured from the unibody sand blasted to remove weight and parts cut out that are not needed for structure, and then tubed for stifness. not much more to pull out. he is in the 2550lb range. regularly, you see 911s with 330flywheel hp 993 engines, weighing close to 2100lbs. in andersons class, thats a decent battle of cat an mouse (turns vs straights) any more hp out of a 911, and there is nothing the big hp vs the weight can buy you! they are different cars and the battles on different tracks can turn out different and thats how it should be.
based on times though, GT3 and GT4 are much faster than any similarly prepared 928 can run with its stockish engine and weight limit. the only way to compete with a 928 is a massive 130% upgrade in engine size, and thats borderline, not even porsche!
out at laguna, ive spun times actally faster than anderson when he came out to Laguna seca in 1999 in speedvision, with a car that is 100hp less than he had and lots less on the chassis as well. that 1:40.2 barely buys me a top 3 finish with the PCA GT4 class. however, with slicks knock a second or two off the time and its still 3 seconds off the winning GT3-4 times .
we have so much data with good drivers running all the tracks, that its silly not to face the reality and close the gaps for some fair competing.
MK
Originally Posted by M758
So mark... Do where do you think GT 928's should be placed?
5.0L and under in GT3 over 5.0L in GT2.
Or
under 5.0L in GT4, and over 5.0 GT3
You saw my proposal in the racing forum on trying to move normally aspriated 944 based cars basicly down 1 GT class and about the 10% weight reduction in "stock" groups. I don't know enough about the 928 to know where it really belongs. I am inclined to believe that in GT3 a 944 Turbo strong car. They make anywhere from 300 whp to 400 whp in most cases. Weights are often 2300 to 2400 or more. I figure that if a 928 S4 can pump out 326 fwhp stock then I'd guess that 350 to 400 at rear wheels would not be too bad for worked over motor.
Your car is what 2700lbs. So that is giving up some 300 to 400 lbs vs a 951. However your car still has steel fenders & stock glass. So I doubt the weght difference between a stripped & ligthened 951 and stripped and lightend 928 would be maybe 200 lbs?
I really don't think a 5.0 928 S4 in GT4 is good thing since it starts with more hp than the benchmark for the class which is the 2000 lbs 280-300 hp 2.8L 911 or 914. Sure it may also weight 700 lbs more, but it has some 30 hp edge with stock motor. May be the 4.7L 928 would be ok in GT4. Especially if the rules are change to allow 3.0L 944/968's in GT4.
So what is lightest 928 race car around? I know the lightest 944 NA I have seen was 2166 lbs. It carried a 968 motor. My 944 spec is 2400 lbs without resorting to fiberglass or lexan. Many 951's are 2300 and up even with with lexan and fiberglass. I remeber Rich A's white 79 928 being 2600 lbs or something. It is stripped, lexan, but still has steel body panels.
One other issue however is the 944 with 928 motor swap. Right now that is rare and expensive, but if you allow a 5.0L V8 in a 968 body shell you have very differently competitive car vs that same motor in 928 body shell. PCA club race rule currently only have displacement limits so that might open a new can of worms if V8's are classes better than inline 4's. Remember I have never seen a 944 motor in a 911 or 914 and don't think I would expect to see one either.
5.0L and under in GT3 over 5.0L in GT2.
Or
under 5.0L in GT4, and over 5.0 GT3
You saw my proposal in the racing forum on trying to move normally aspriated 944 based cars basicly down 1 GT class and about the 10% weight reduction in "stock" groups. I don't know enough about the 928 to know where it really belongs. I am inclined to believe that in GT3 a 944 Turbo strong car. They make anywhere from 300 whp to 400 whp in most cases. Weights are often 2300 to 2400 or more. I figure that if a 928 S4 can pump out 326 fwhp stock then I'd guess that 350 to 400 at rear wheels would not be too bad for worked over motor.
Your car is what 2700lbs. So that is giving up some 300 to 400 lbs vs a 951. However your car still has steel fenders & stock glass. So I doubt the weght difference between a stripped & ligthened 951 and stripped and lightend 928 would be maybe 200 lbs?
I really don't think a 5.0 928 S4 in GT4 is good thing since it starts with more hp than the benchmark for the class which is the 2000 lbs 280-300 hp 2.8L 911 or 914. Sure it may also weight 700 lbs more, but it has some 30 hp edge with stock motor. May be the 4.7L 928 would be ok in GT4. Especially if the rules are change to allow 3.0L 944/968's in GT4.
So what is lightest 928 race car around? I know the lightest 944 NA I have seen was 2166 lbs. It carried a 968 motor. My 944 spec is 2400 lbs without resorting to fiberglass or lexan. Many 951's are 2300 and up even with with lexan and fiberglass. I remeber Rich A's white 79 928 being 2600 lbs or something. It is stripped, lexan, but still has steel body panels.
One other issue however is the 944 with 928 motor swap. Right now that is rare and expensive, but if you allow a 5.0L V8 in a 968 body shell you have very differently competitive car vs that same motor in 928 body shell. PCA club race rule currently only have displacement limits so that might open a new can of worms if V8's are classes better than inline 4's. Remember I have never seen a 944 motor in a 911 or 914 and don't think I would expect to see one either.
06-03-2005, 07:29 PM
#6
Race Director
Thread Starter
Ok... So a few what ifs here.. (assume we move 944 motors down too)
So how about
This
GT6 =
Aircooled / Watercooled horzonatally opposed engines 1.75L - Normally Aspirated
Inline 4 cylinders to 2.2L - Normally Aspirated
Turbo cars to 1.75L after 1.3 factor
GT5 =
Aircooled / Watercooled horzonatally opposed engines 1.75 to 2.2L Normally Aspirated
Inline 4 cylinders 2.2L to 2.8L Normally Aspirated
Turbo cars 1.75 to 2.2L after 1.3 factor
GT4 =
Aircooled / Watercooled horzonatally opposed engines 2.2L to 2.808L normally aspirated
Inline 4 cylinders 2.8L to 3.2L Normally Aspriated
2 valve per cylinder V8 engines to 4.9L Normally Aspirated
Turbo engines 2.2 to 2.808L after 1.3 factor
GT3
Aircooled / Watercooled horzonatally opposed engines 2.808L to 3.4L normally aspirated
Inline 4 cylinders over 3.2L Normally Aspirated
V8 engines to 5.4L Normally Aspriated
Turbo engines 2.808 to 3.4L after 1.3 factor
GT2
Aircooled horzonatally opposed engines over 3.4L normally aspirated
V8 Engines over 5.4L Normally Aspirated
GT1
Turbo motors over 3.4L after 1.3 factor
1)
So we allow sub 5.0L V8's in GT4 - Competition is 2.8L 911 motors at 280-300 hp, 968 motors at 250 -280 hp. Note cayenne V8's would be in GT3 however.
GT3 = 3.4L 911 at 340 hp and 2.5 & 2.6L 951's at 350-400 whp, 928 motors at 350 hp 5.0L to 5.5L, Cayenne V8's
GT2 = 360+ hp 911 motors, big 6.5L 928 motors at 400 hp.
Seems ok to me.
Now what about a someone stuffing a 4.9L 928 motor in 914? Assume 2100 lbs and how much whp? (hopefully not over 300 or so)
What about a 914 with a 5.0L or 5.4L 928 motor in GT3? Or a 944 Turbo with 5.4L 928 motor?
So how about
This
GT6 =
Aircooled / Watercooled horzonatally opposed engines 1.75L - Normally Aspirated
Inline 4 cylinders to 2.2L - Normally Aspirated
Turbo cars to 1.75L after 1.3 factor
GT5 =
Aircooled / Watercooled horzonatally opposed engines 1.75 to 2.2L Normally Aspirated
Inline 4 cylinders 2.2L to 2.8L Normally Aspirated
Turbo cars 1.75 to 2.2L after 1.3 factor
GT4 =
Aircooled / Watercooled horzonatally opposed engines 2.2L to 2.808L normally aspirated
Inline 4 cylinders 2.8L to 3.2L Normally Aspriated
2 valve per cylinder V8 engines to 4.9L Normally Aspirated
Turbo engines 2.2 to 2.808L after 1.3 factor
GT3
Aircooled / Watercooled horzonatally opposed engines 2.808L to 3.4L normally aspirated
Inline 4 cylinders over 3.2L Normally Aspirated
V8 engines to 5.4L Normally Aspriated
Turbo engines 2.808 to 3.4L after 1.3 factor
GT2
Aircooled horzonatally opposed engines over 3.4L normally aspirated
V8 Engines over 5.4L Normally Aspirated
GT1
Turbo motors over 3.4L after 1.3 factor
1)
So we allow sub 5.0L V8's in GT4 - Competition is 2.8L 911 motors at 280-300 hp, 968 motors at 250 -280 hp. Note cayenne V8's would be in GT3 however.
GT3 = 3.4L 911 at 340 hp and 2.5 & 2.6L 951's at 350-400 whp, 928 motors at 350 hp 5.0L to 5.5L, Cayenne V8's
GT2 = 360+ hp 911 motors, big 6.5L 928 motors at 400 hp.
Seems ok to me.
Now what about a someone stuffing a 4.9L 928 motor in 914? Assume 2100 lbs and how much whp? (hopefully not over 300 or so)
What about a 914 with a 5.0L or 5.4L 928 motor in GT3? Or a 944 Turbo with 5.4L 928 motor?
06-03-2005, 07:47 PM
#7
Rennlist Member
Looks good and makes perfect sence. Now, as far as stuffing the 928 motor in the 911 or 914, thats easy, now it just fits the greater than 3.4 liter mark for the 911 or 914 which is GT2 (i guess something like the update backdate rule???) Probably best to keep all 8 cylinders in 928 chassis, and any other change just follows the 6 cylinder rules for displacement. (ie anything greater than 3.4 is GT2
Only note is to the "4 cylinder opposed engine" shouldnt it be 4-6 cylinder?
Nice job. move on to fairness and parity!
anyone stuffing a 928 engine in a 911 or 914 is pretty nuts, as the weight of the 928 engine is in the 650lb range!! so, you wouldnt find too many 2100lb 911s with a 928 engine!!
Mk
Only note is to the "4 cylinder opposed engine" shouldnt it be 4-6 cylinder?
Nice job. move on to fairness and parity!
anyone stuffing a 928 engine in a 911 or 914 is pretty nuts, as the weight of the 928 engine is in the 650lb range!! so, you wouldnt find too many 2100lb 911s with a 928 engine!!
Mk
Originally Posted by M758
Ok... So a few what ifs here.. (assume we move 944 motors down too)
So how about
This
GT6 =
Aircooled / Watercooled horzonatally opposed engines 1.75L - Normally Aspirated
Inline 4 cylinders to 2.2L - Normally Aspirated
Turbo cars to 1.75L after 1.3 factor
GT5 =
Aircooled / Watercooled horzonatally opposed engines 1.75 to 2.2L Normally Aspirated
Inline 4 cylinders 2.2L to 2.8L Normally Aspirated
Turbo cars 1.75 to 2.2L after 1.3 factor
GT4 =
Aircooled / Watercooled horzonatally opposed engines 2.2L to 2.808L normally aspirated
Inline 4 cylinders 2.8L to 3.2L Normally Aspriated
2 valve per cylinder V8 engines to 4.9L Normally Aspirated
Turbo engines 2.2 to 2.808L after 1.3 factor
GT3
Aircooled / Watercooled horzonatally opposed engines 2.808L to 3.4L normally aspirated
Inline 4 cylinders over 3.2L Normally Aspirated
V8 engines to 5.4L Normally Aspriated
Turbo engines 2.808 to 3.4L after 1.3 factor
GT2
Aircooled horzonatally opposed engines over 3.4L normally aspirated
V8 Engines over 5.4L Normally Aspirated
GT1
Turbo motors over 3.4L after 1.3 factor
1)
So we allow sub 5.0L V8's in GT4 - Competition is 2.8L 911 motors at 280-300 hp, 968 motors at 250 -280 hp. Note cayenne V8's would be in GT3 however.
GT3 = 3.4L 911 at 340 hp and 2.5 & 2.6L 951's at 350-400 whp, 928 motors at 350 hp 5.0L to 5.5L, Cayenne V8's
GT2 = 360+ hp 911 motors, big 6.5L 928 motors at 400 hp.
Seems ok to me.
Now what about a someone stuffing a 4.9L 928 motor in 914? Assume 2100 lbs and how much whp? (hopefully not over 300 or so)
What about a 914 with a 5.0L or 5.4L 928 motor in GT3? Or a 944 Turbo with 5.4L 928 motor?
So how about
This
GT6 =
Aircooled / Watercooled horzonatally opposed engines 1.75L - Normally Aspirated
Inline 4 cylinders to 2.2L - Normally Aspirated
Turbo cars to 1.75L after 1.3 factor
GT5 =
Aircooled / Watercooled horzonatally opposed engines 1.75 to 2.2L Normally Aspirated
Inline 4 cylinders 2.2L to 2.8L Normally Aspirated
Turbo cars 1.75 to 2.2L after 1.3 factor
GT4 =
Aircooled / Watercooled horzonatally opposed engines 2.2L to 2.808L normally aspirated
Inline 4 cylinders 2.8L to 3.2L Normally Aspriated
2 valve per cylinder V8 engines to 4.9L Normally Aspirated
Turbo engines 2.2 to 2.808L after 1.3 factor
GT3
Aircooled / Watercooled horzonatally opposed engines 2.808L to 3.4L normally aspirated
Inline 4 cylinders over 3.2L Normally Aspirated
V8 engines to 5.4L Normally Aspriated
Turbo engines 2.808 to 3.4L after 1.3 factor
GT2
Aircooled horzonatally opposed engines over 3.4L normally aspirated
V8 Engines over 5.4L Normally Aspirated
GT1
Turbo motors over 3.4L after 1.3 factor
1)
So we allow sub 5.0L V8's in GT4 - Competition is 2.8L 911 motors at 280-300 hp, 968 motors at 250 -280 hp. Note cayenne V8's would be in GT3 however.
GT3 = 3.4L 911 at 340 hp and 2.5 & 2.6L 951's at 350-400 whp, 928 motors at 350 hp 5.0L to 5.5L, Cayenne V8's
GT2 = 360+ hp 911 motors, big 6.5L 928 motors at 400 hp.
Seems ok to me.
Now what about a someone stuffing a 4.9L 928 motor in 914? Assume 2100 lbs and how much whp? (hopefully not over 300 or so)
What about a 914 with a 5.0L or 5.4L 928 motor in GT3? Or a 944 Turbo with 5.4L 928 motor?
Trending Topics
06-03-2005, 09:55 PM
#8
Rennlist Member
it is all about weight, power, tire sizes..in that order, and has nothing to do with displacement.
I can build a 5.0 4 valve engine with close to 600 crank hp without issue, great cost...but hey...we are just talkin..right.
And, no one in any racing org cares about the 928, so it is a moot point.
BUT best bet, as soem racers and Don hanson..the KING of hp, know, it is really hard to beat a well set up 928 stroker.
Marc
I can build a 5.0 4 valve engine with close to 600 crank hp without issue, great cost...but hey...we are just talkin..right.
And, no one in any racing org cares about the 928, so it is a moot point.
BUT best bet, as soem racers and Don hanson..the KING of hp, know, it is really hard to beat a well set up 928 stroker.
Marc
Don hanson..the KING of hp.
06-03-2005, 10:22 PM
#11
Nordschleife Master
How about looking at the last few years' results? That'll tell you how cars are doing on different tracks.
It's all there on the PCA website. http://www.pca.org/pca/clubrace/2004_results/index.htm
I follow this a bit and my take is the big-displacement stroker cars do fine, and win, in GT2. The stock-block cars run well, but don't win, in GT3.
It's all there on the PCA website. http://www.pca.org/pca/clubrace/2004_results/index.htm
I follow this a bit and my take is the big-displacement stroker cars do fine, and win, in GT2. The stock-block cars run well, but don't win, in GT3.
06-03-2005, 11:02 PM
#12
Race Director
Thread Starter
Originally Posted by marc@DEVEK
I can build a 5.0 4 valve engine with close to 600 crank hp without issue, great cost...but hey...we are just talkin..right.
Marc
Marc
Last edited by M758; 06-03-2005 at 11:54 PM.
06-04-2005, 01:08 PM
#13
Three Wheelin'
Originally Posted by marc@DEVEK
I can build a 5.0 4 valve engine with close to 600 crank hp without issue,
Originally Posted by M758
If that is true thne the 928 motors do belong in GT2.
A 'paper' 5.0L engine can be made to output 600 hp at the crank; it's rwhp would be:
600 crank hp x .85 = 510 rwhp
A working full-meal-deal 6.5L comparitively did 'only' 550 rwhp:
http://www.devek.net/index.php?page=nfo_cars_whitecar
So the claim is that with 1.5L less displacement, the 5.0's output would be nearly the same as the fully-massaged 6.5L engine, minus 40 rwhp of course.
Hmm, does that sound reasonable?
Alright then, let's look at it from another angle.
The fully massaged 6.5L engine puts out at the crank:
550 rwhp / .85 = 647 crank hp
The 'paper' 5.0 engine claim is 600 crank hp
Again, that's only a 47 crank hp difference using 1.5L less displacement; 'the claim' still doesn't look reasonable.
Now let's try looking at HP/Liter to see if the picture starts to clear up just a little bit.
The fully massaged 6.5L engine: 647 chp / 6.5 L = 99.5 chp / Liter
The 'paper' 5.0L engine: 600 chp / 5.0 L = 120 chp / Liter
That's a full 20% increase in crank hp per liter which is absolutely HUGE. For comparison's sake, 120 chp/L NA is the same output as the ultra-high-tech Honda S2000.
By the way, at 120 chp/ L that would mean a 6.5L would do:
120 chp x 6.5L = 780 crank hp, or
780 chp x .85 = 663 rwhp
Concluding, the claim of a 32v 5.0L NA 928 engine outputting 600 crank hp does not sound reasonable, at all.
Originally Posted by marc@DEVEK
I can build a 5.0 4 valve engine with close to 600 crank hp without issue,
The 'issue' is, and big issue at that, until a hard-copy is actually dyno'd, it's safe to say:
...but hey...we are just talkin..right.
06-04-2005, 01:20 PM
#14
Race Director
It seems a well built 4.7L Euro car race ready would be a good car to have to GT4....figure over 350hp at the wheels and maybe 2700lbs.... Sure some 951's or 968's or 911RS would still be competitive...but the Euro should be able to hold its own?
Where would a S/C or turbo 928 compete?
Where would a S/C or turbo 928 compete?
06-04-2005, 11:44 PM
#15
Race Director
Thread Starter
Originally Posted by IcemanG17
Where would a S/C or turbo 928 compete?
This is place for all 911 turbos and 951 at 2.7 or 3.0L.
For GT3 the max turbo car displacement is 2.6L (or so). Given that there many competive 951's in GT3 I don't think it makes sence to change that. Max NA displacement is 3.4L.
GT2 is strictly large displacment NA cars.