Winston/Nextel Cup Cars
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Joined: Jan 2003
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From: Mooresville, NC
Originally posted by aggiez28
deffinatly. i was just trying to say ya dont need that much hpp to go that fast. other things are importnt too
brook
deffinatly. i was just trying to say ya dont need that much hpp to go that fast. other things are importnt too
brook
It's a viscious cycle. Basically, I geuss it's that given aero capable of running 225 all the way around, you'd need a lot of HP to push through all that short track kind of aero work. I highly doubt the ~775 would get you there.
NOTE: The other day I read that the late John Lingenfelter said he needed 500hp to make a C5 go 200mph. He put in a 500hp engine and hit 199 or something. Just posting that in regard to a post I read earlier.
Last edited by Black6SpdTA; Feb 24, 2004 at 09:51 PM.
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Originally posted by Rippin92RS
NOTE: The other day I read that the late John Lingenfelter said he needed 500hp to make a C5 go 200mph. He put in a 500hp engine and hit 199 or something. [/B]
NOTE: The other day I read that the late John Lingenfelter said he needed 500hp to make a C5 go 200mph. He put in a 500hp engine and hit 199 or something. [/B]
http://www.babcox.com/editorial/ar/eb40250.htm
http://www.photonics.com/spectra/tec...55/QX/read.htm
to say this thread is the tip of the iceburg is an understatement. o can only image this heaven these guy live in. i bet like one of them drives an old chevelle and another a 00 vette and another a superbee and everyday they race to where ever the loser paying lunch and they talk about theory while eating the best food. oh man one day that could be me.
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From: Upstate NY
Originally posted by number77
wouldn't that be something if the guys in bowling green designed it like that on purpose?
Yeah, the C5 WAS designed to go ~170 with 350 as-installed hp.
i think the tranny is what gets the least apreciation. besides friction and cooling the ratio itself is a big part. they have to have a good ractio to get from 0 to cruise (whatever pit speed is) and a good ratio to get up to speed from pit to track, and a good ratio to get to top speed (track speed of course) from pace speed. and a good ratio to accelerate out of the corners (some tracks have corners that don't match eachother) and get to that top speed, and and finally the best ratio to get the most out of the engine with the best fuel efficiency at an average lap. and thats just one track, hahah.
Well, on most Cup tracks, with the exception of the two road courses and Pocono, virtually all the racing is done in 4th (of 4) which is 1:1 ratio, which is the most efficient, least heat generating and strongest.
Daytona and Talladega with the low hp engines with low max rpms need the correct gears for getting up to speed. That and excellent brakes for slowing to pit speed can, and does effect position changes.
FWIW, pit radio communication at the start of Daytona indicated 55 mph (pit speed) was 6000 in 1st and 3700 in 2nd for one car. Most guys were pulling 7100-7200 at 185 mph which gives about a 3.00 rear gear (+ or - .10 or so), so first was about 2.85 and second 1.75, and (guessing ) 3rd about 1.2-1.25.
About 88% of the Cup races are raced in 1:1 (after accelerating out of the pits) so it's rear gear ratio that's important. What changes is the rpm range the engine sees. At Daytona 300 rpm seems to be about the range (6900-7200 or 68-71). At some short tracks it's more like 6000-9500, a 3500 rpm band. Other tracks might be a 1500 range (high 7s to low 9s). The transmissions only get a tough workout at the road courses. Some use all 4 gears (coming out of turn 1 @ Watkins Glen) and some only use 2-3-4. I would suggest that road course transmissions are the strongest, best cooled and contain the most exotic parts of any of the tracks.
you also have to look into the smaller things like honing. you know they heat up the block and torque a plate ontop of it to get the shape of the engine at operating temp and then hone it with a laser and then there is probably other things they do like what i read in this article about using a laser to "texture" the cylinder walls in slashes to hold oil better and by holding insanely small amount there is almost no metal to metal contact.
http://www.babcox.com/editorial/ar/eb40250.htm
http://www.photonics.com/spectra/tec...55/QX/read.htm
Yep, "hot honing" is popular. Laser structuring of the bores may be less so, but it's probably used, as are sleeves which may be of a material different from the grey cast iron of the blocks. At least, sleeves are centrifugally cast and are probably more dense than poured cast iron. Coatings on cylinder walls are probably used.
to say this thread is the tip of the iceburg is an understatement. o can only image this heaven these guy live in. i bet like one of them drives an old chevelle and another a 00 vette and another a superbee and everyday they race to where ever the loser paying lunch and they talk about theory while eating the best food. oh man one day that could be me.
I would suggest that Nextel Cup competition is so competitive that, for the teams, it's more like a "living hell" than a heaven with the need to perform and excell all the time. Yeah, many get paid very well, but boy do they earn their pay!
wouldn't that be something if the guys in bowling green designed it like that on purpose?
Yeah, the C5 WAS designed to go ~170 with 350 as-installed hp.
i think the tranny is what gets the least apreciation. besides friction and cooling the ratio itself is a big part. they have to have a good ractio to get from 0 to cruise (whatever pit speed is) and a good ratio to get up to speed from pit to track, and a good ratio to get to top speed (track speed of course) from pace speed. and a good ratio to accelerate out of the corners (some tracks have corners that don't match eachother) and get to that top speed, and and finally the best ratio to get the most out of the engine with the best fuel efficiency at an average lap. and thats just one track, hahah.
Well, on most Cup tracks, with the exception of the two road courses and Pocono, virtually all the racing is done in 4th (of 4) which is 1:1 ratio, which is the most efficient, least heat generating and strongest.
Daytona and Talladega with the low hp engines with low max rpms need the correct gears for getting up to speed. That and excellent brakes for slowing to pit speed can, and does effect position changes.
FWIW, pit radio communication at the start of Daytona indicated 55 mph (pit speed) was 6000 in 1st and 3700 in 2nd for one car. Most guys were pulling 7100-7200 at 185 mph which gives about a 3.00 rear gear (+ or - .10 or so), so first was about 2.85 and second 1.75, and (guessing ) 3rd about 1.2-1.25.
About 88% of the Cup races are raced in 1:1 (after accelerating out of the pits) so it's rear gear ratio that's important. What changes is the rpm range the engine sees. At Daytona 300 rpm seems to be about the range (6900-7200 or 68-71). At some short tracks it's more like 6000-9500, a 3500 rpm band. Other tracks might be a 1500 range (high 7s to low 9s). The transmissions only get a tough workout at the road courses. Some use all 4 gears (coming out of turn 1 @ Watkins Glen) and some only use 2-3-4. I would suggest that road course transmissions are the strongest, best cooled and contain the most exotic parts of any of the tracks.
you also have to look into the smaller things like honing. you know they heat up the block and torque a plate ontop of it to get the shape of the engine at operating temp and then hone it with a laser and then there is probably other things they do like what i read in this article about using a laser to "texture" the cylinder walls in slashes to hold oil better and by holding insanely small amount there is almost no metal to metal contact.
http://www.babcox.com/editorial/ar/eb40250.htm
http://www.photonics.com/spectra/tec...55/QX/read.htm
Yep, "hot honing" is popular. Laser structuring of the bores may be less so, but it's probably used, as are sleeves which may be of a material different from the grey cast iron of the blocks. At least, sleeves are centrifugally cast and are probably more dense than poured cast iron. Coatings on cylinder walls are probably used.
to say this thread is the tip of the iceburg is an understatement. o can only image this heaven these guy live in. i bet like one of them drives an old chevelle and another a 00 vette and another a superbee and everyday they race to where ever the loser paying lunch and they talk about theory while eating the best food. oh man one day that could be me.
I would suggest that Nextel Cup competition is so competitive that, for the teams, it's more like a "living hell" than a heaven with the need to perform and excell all the time. Yeah, many get paid very well, but boy do they earn their pay!
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Joined: Dec 2002
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From: Indiana
Re: Winston/Nextel Cup Cars
my understanding was that the cams are generally not as big as one would think. I got ahold of the cams specs on the bush series cars (slower, but still gobbs of power) and they were all right around .600 lift. like bret says, there's soo many coatings and blendings that go on to help get that power. Roush, DEI, etc don't spend millions of dollars on guys throwing together shelf parts. Nascar has descrete rules on about everything, so its all about the small things. I'm not sure of hp number excactly, but i Ford is not 10-15hp behind, as someone previously stated. nobody would survive being 10-15hp behind. I'd say the power difference from the worst nextel cup teams to the best nextel cups teams are only a bit over 5hp. My estimate excludes the poor guys trying to make a run. Those guys don't count. In the nascar world, i don't think it's much of a secret as to what kind of numbers they put up and parts they use. I'm sure they all know each other's stuff. But the secrets are with the coatings and smoothing they do to get these things going. not to mention those engines are balanced better than our brains.
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Joined: Feb 1999
Posts: 35
From: Concord, NC, USA
Re: Winston/Nextel Cup Cars
Originally Posted by blackztpi
my understanding was that the cams are generally not as big as one would think. I got ahold of the cams specs on the bush series cars (slower, but still gobbs of power) and they were all right around .600 lift. like bret says, there's soo many coatings and blendings that go on to help get that power. Roush, DEI, etc don't spend millions of dollars on guys throwing together shelf parts. Nascar has descrete rules on about everything, so its all about the small things. I'm not sure of hp number excactly, but i Ford is not 10-15hp behind, as someone previously stated. nobody would survive being 10-15hp behind. I'd say the power difference from the worst nextel cup teams to the best nextel cups teams are only a bit over 5hp. My estimate excludes the poor guys trying to make a run. Those guys don't count. In the nascar world, i don't think it's much of a secret as to what kind of numbers they put up and parts they use. I'm sure they all know each other's stuff. But the secrets are with the coatings and smoothing they do to get these things going. not to mention those engines are balanced better than our brains.
They also do some interesting things with oil control, and the first time I held a cup pushrod in my hand I couldn't believe it (hey light it was given the huge diamter). They also make intakes on the rapid prototype machine, and run the plastic intakes on the dyno.
Most of my engineering friends that work in the industry don't consider it heaven. Many of them drive normal cars, and the 12 hours days do a great job of numbing you to any fun stuff, very quickly.
Last edited by I8AStang; Jul 18, 2006 at 07:16 AM.
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From: Charlotte,NC
Re: Winston/Nextel Cup Cars
whoa...you guys are all off...i am currently going to NTI in Mooresville, only 2 classes left on the Nascar side. ive been through nascar engines 1 and 2 and they dont hold back any secrets, they lay it all out when it comes to the current rules and secrets the teams have. if you guys would really like the current rules for the engines ill grab my notes out one night and type them out for you...you guys are correct on the bore and stroke but compression ratio for the nextel cup cars are limited to 12.0:1. and the cubic inches must be between 350 and 358, no smaller no larger, and you ask why they would want to go smaller than 350, they can make more power with less cubic inches on the restrictor plate motors, so nascar made 350 the smallest you can go. ill get the specifics out and type them for you guys....later
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Joined: Sep 2004
Posts: 34
Re: Winston/Nextel Cup Cars
They dont tell you the REAL SECRETS that are used right now!
Originally Posted by CamaroTD
whoa...you guys are all off...i am currently going to NTI in Mooresville, only 2 classes left on the Nascar side. ive been through nascar engines 1 and 2 and they dont hold back any secrets, they lay it all out when it comes to the current rules and secrets the teams have. if you guys would really like the current rules for the engines ill grab my notes out one night and type them out for you...you guys are correct on the bore and stroke but compression ratio for the nextel cup cars are limited to 12.0:1. and the cubic inches must be between 350 and 358, no smaller no larger, and you ask why they would want to go smaller than 350, they can make more power with less cubic inches on the restrictor plate motors, so nascar made 350 the smallest you can go. ill get the specifics out and type them for you guys....later
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From: Kilgore TX 75662
Re: Winston/Nextel Cup Cars
Originally Posted by CamaroTD
...they dont hold back any secrets, they lay it all out when it comes to the current rules and secrets the teams have.... and you ask why they would want to go smaller than 350, they can make more power with less cubic inches on the restrictor plate motors, so nascar made 350 the smallest you can go. ill get the specifics out and type them for you guys....later
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Posts: 27
From: Charlotte,NC
Re: Winston/Nextel Cup Cars
its funny how you guys and everyone else thinks that these engines are some huge mystery, yes they have little tricks and secrets that the engine builders try to get away with but its not some huge mystery, theres only so many things you can do with the motor. and yes i do believe what they tell me because many of my teachers worked in the engine building programs of some of the big name teams, like DEI and Hendricks. And also i do know a couple of people who still work for some of the teams in the engine programs and the current things that they are trying. And also were you refering that you didnt believe me when i said they could make more power on less cubic inches on the restrictor plate motors? its very simple concept that been proven and i can share if you would like.
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From: Upstate NY
Re: Winston/Nextel Cup Cars
Originally Posted by CamaroTD
its funny how you guys and everyone else thinks that these engines are some huge mystery, yes they have little tricks and secrets that the engine builders try to get away with but its not some huge mystery, theres only so many things you can do with the motor. and yes i do believe what they tell me because many of my teachers worked in the engine building programs of some of the big name teams, like DEI and Hendricks. And also i do know a couple of people who still work for some of the teams in the engine programs and the current things that they are trying. And also were you refering that you didnt believe me when i said they could make more power on less cubic inches on the restrictor plate motors? its very simple concept that been proven and i can share if you would like.
Well, not everyone else.
If you want some good info on Hendricks and Everham Cup engines, recent issues of race engine TECHNOLOGY magazine had some pretty good articles with fairly good numbers. There were almost no photos of intake manifold internals, and no cam timing specs of course. There are good reasons for that.
Many of the parts and who makes them, as well as fairly good power output info (for 2005 engines) was available. No real "secrets" were revealed, as you might suspect. The articles did point out how highly developed Cup engines really are.
If you built a plate engine with well fewer than 350 cubes you could reduce friction losses which would net more flywheel hp from the same air consumption. That would involve much more development costs, which are excessive for the 4 plate races anyway.
FWIW, unrestricted Cup valve lifts are considerably more than the .600 quoted above, even before lofting.
The high-end Cup engines are still only a fraction of the cost of a top running ProStock engine. Round numbers might be $85K vs. $200K+. Of course the volume of Cup engines a good shop builds helps with the costs vs. just the few engines a PS team has.
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From: houston, Tx
Re: Winston/Nextel Cup Cars
Originally Posted by baddog43
thats pretty good info but NASCAR does not allow roller lifters they are limited to flat tappet
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From: houston, Tx
Re: Winston/Nextel Cup Cars
Also NASCAR put out the displacement rules when RAMPANT restrictor plate cheating was going on and many were using that small engine mumbo jumbo to try and cover their cheating. That's what they said was causing their higher rpm instead of all the air leaks they were hiding.
In theory you might be able to squeak some more air by an SEO plate but the extra rpm eats up the tiny amount of extra power in friction fast. Also these are severely restricted engine they were playing with and featured SEO (sharp edge orifice) restrictors. Using smaller engines made the airflow more continuous with smaller higher frequency pulses and slower peak airflow across the NASCAR SEO plates which really could increase total airflow through them.
The main thing to remember though is that there are tons of restricted classes that allow you to go as small as you would want with NO penalties other than the lower hp you will net. People don't do it much and in fact the rule is just as all other race classes where they always end up capping UPPER displacement not lower displacement.
People just love these weird ideas but the truth is that ALL engines are restricted by something and it never pays to reduce displacement on them either if you aren't gettting some kind of weight break etc. for it. You just slow down 99 percent of the time.
In theory you might be able to squeak some more air by an SEO plate but the extra rpm eats up the tiny amount of extra power in friction fast. Also these are severely restricted engine they were playing with and featured SEO (sharp edge orifice) restrictors. Using smaller engines made the airflow more continuous with smaller higher frequency pulses and slower peak airflow across the NASCAR SEO plates which really could increase total airflow through them.
The main thing to remember though is that there are tons of restricted classes that allow you to go as small as you would want with NO penalties other than the lower hp you will net. People don't do it much and in fact the rule is just as all other race classes where they always end up capping UPPER displacement not lower displacement.
People just love these weird ideas but the truth is that ALL engines are restricted by something and it never pays to reduce displacement on them either if you aren't gettting some kind of weight break etc. for it. You just slow down 99 percent of the time.
