Techie question
Discussion
I have a rough idea of what it takes for a TF dragster to make the transition from running 4.8 secs to 4.5, ie more fuel, more air, more spark, more clutch and generally more of everything. However, I have no idea of what it takes for a PS car to go from running 6.7 secs as Jimmy Alund and Michael Malmgren have been doing stateside, to running 6.5 secs with the big boys. Anybody?
the density of the air without a doubt ! humid air makes for big power and the race teams at the "gators" have always benifited from this ,i would have thought the humidity would have helped the nitro classes too but it seems they didnt get the big gains the non nitro cars got .all the non nitro classes saw big power gains ! did anyone notice how well the "pro mods" were running ? lots of "five ninetys" being run and huge miles per hours . the pro stock bikes had low et,s in the six nineties and mph gains too.
The performance difference between Micheal and Jimmy, and the NHRA boys is down to 2 simple things: Track-time and horsepower.
As we've seen, over the last couple of weeks while they've been testing, the Swedish boys have steadily chipped away at their et's and got some real decent numbers out of their cars, which shows the importance of time spent on the strip. None of the Scandanavian teams have the budget, weather or resources to test week in week out like the Americans do.
As far as horsepower goes though, that comes down to cubic dollars unfortunately, and there's no way any of the FIA teams can compete on that level. The likes of KB Racing (Anderson & Line), WJ Racing (Warren & Kurt), J&J Racing (Allen Johnson & Richie Stevens), Cagnazzi Racing (Jeg Coughlin Jr & Dave Connolly) etc etc all have their own in-house engine programs, with full time staff employed to do pull after pull on the dyno to extract every last ounce of power. All of them have the capabilities to develop and produce experimental parts for dyno analysis to ensure they stay at the top of their game. From carbs, to manifolds, headers, ignition system, rotating assemblies, the lot, every piece of a top NHRA motor is precision made from hand picked forged parts. You can guarantee that as Greg Anderson was ripping off a 6.53 in Gainesville, there were guys in the shop at Las Vegas developing a stonger, more powerful motor for him to utilise next time.
For the rest of the racers, like the Europeans, this is out of the question and they have to turn to people like Bob Ingles, Steve Schmidt, Larry Morgan etc, to lease an engine program. This is a very similar scenario to "customer engines" in Formula 1. Although these engines are far from cheap, and are still cutting edge, they lack the benefit of the ongoing development progress that the in-house programs gain from. As for the chances of being able to lease a KB, WJ or J&J engine?....forget it. Maybe 10 years ago it would be just about viable, but not now, each team spends too much time and money on R&D to let another racer have a piece of the pie.
The only thing that will change the situation, is if that a sufficient number of teams and drivers invest in an engine program like Bob Ingles', to give him the budget, feedback and sheer data that it takes to develop a competitive package. Unless there is a Top Fuel style "spec motor" rule package that comes in-place though, I can't see it happening. Pro Stock is one of the hardest places for the "little guy" to compete now. In the IHRA, it's not such a big problem as all the Ford engines come from Jon Kaase, and the GM versions from Sonny Leonard, so all the teams benefit from development at the same time, and the class progresses as a whole.
As we've seen, over the last couple of weeks while they've been testing, the Swedish boys have steadily chipped away at their et's and got some real decent numbers out of their cars, which shows the importance of time spent on the strip. None of the Scandanavian teams have the budget, weather or resources to test week in week out like the Americans do.
As far as horsepower goes though, that comes down to cubic dollars unfortunately, and there's no way any of the FIA teams can compete on that level. The likes of KB Racing (Anderson & Line), WJ Racing (Warren & Kurt), J&J Racing (Allen Johnson & Richie Stevens), Cagnazzi Racing (Jeg Coughlin Jr & Dave Connolly) etc etc all have their own in-house engine programs, with full time staff employed to do pull after pull on the dyno to extract every last ounce of power. All of them have the capabilities to develop and produce experimental parts for dyno analysis to ensure they stay at the top of their game. From carbs, to manifolds, headers, ignition system, rotating assemblies, the lot, every piece of a top NHRA motor is precision made from hand picked forged parts. You can guarantee that as Greg Anderson was ripping off a 6.53 in Gainesville, there were guys in the shop at Las Vegas developing a stonger, more powerful motor for him to utilise next time.
For the rest of the racers, like the Europeans, this is out of the question and they have to turn to people like Bob Ingles, Steve Schmidt, Larry Morgan etc, to lease an engine program. This is a very similar scenario to "customer engines" in Formula 1. Although these engines are far from cheap, and are still cutting edge, they lack the benefit of the ongoing development progress that the in-house programs gain from. As for the chances of being able to lease a KB, WJ or J&J engine?....forget it. Maybe 10 years ago it would be just about viable, but not now, each team spends too much time and money on R&D to let another racer have a piece of the pie.
The only thing that will change the situation, is if that a sufficient number of teams and drivers invest in an engine program like Bob Ingles', to give him the budget, feedback and sheer data that it takes to develop a competitive package. Unless there is a Top Fuel style "spec motor" rule package that comes in-place though, I can't see it happening. Pro Stock is one of the hardest places for the "little guy" to compete now. In the IHRA, it's not such a big problem as all the Ford engines come from Jon Kaase, and the GM versions from Sonny Leonard, so all the teams benefit from development at the same time, and the class progresses as a whole.
Rat_Fink_67 said:
[quote=theMighty]And possibly maybe that the European motors are a different spec to the US ones as they have been specifically designed to run on the unleaded fuel which is the spec fuel for PS over here unlike the NHRA spec leaded fuel?
Yeah, they run a little less compression over here, and no doubt slightly less ignition advance....same thing that keeps the European nitrous Pro Mods from running the times seen in the US.
noggin the nog said:
the density of the air without a doubt ! humid air makes for big power and the race teams at the "gators" have always benifited from this ,i would have thought the humidity would have helped the nitro classes too but it seems they didnt get the big gains the non nitro cars got .all the non nitro classes saw big power gains ! did anyone notice how well the "pro mods" were running ? lots of "five ninetys" being run and huge miles per hours . the pro stock bikes had low et,s in the six nineties and mph gains too.
I don't know where all this came from but I'm sure I have always been led to believe:
"Dense Air" like we get often at the Pod increases power if the correct mixture is maintained
"Humid Air" sadly like we also get over here, decreases power as the water "grains" displace oxygen content in the air.
The air in Q3 (the quick session) at Gainesville was indeed very dense, (for the US anyway) the corrected altitude being around 900ft but also the air was relatively dry (17% humidity) making for record setting conditions.
My thoughts on the lack of power increase in the nitro classes...
1) Nitromethane releases a percentage of the oxygen it uses to burn from its own chemical breakdown, thus the percentage gains from density would be smaller than the gas or alcohol
2) Its ok having the good air but can you pump enough fuel through to keep the mixture rich enough to stop it going bang, or over-revving and dropping holes with the power increase, etc etc, if not... less blower drive surely? The nitro cars seem somewhat more of a balancing act to me.
3) If you make more power can you actually get it down to the track. Its been said that a good PS track is not a good Nitro track and vice versa
Where's Pi5ton when you need him?
PETE!!!???!!!
He's a man with proper answers!
Edited by theMighty on Tuesday 20th March 12:08
Edited by theMighty on Tuesday 20th March 12:10
theMighty said:
noggin the nog said:
the density of the air without a doubt ! humid air makes for big power and the race teams at the "gators" have always benifited from this ,i would have thought the humidity would have helped the nitro classes too but it seems they didnt get the big gains the non nitro cars got .all the non nitro classes saw big power gains ! did anyone notice how well the "pro mods" were running ? lots of "five ninetys" being run and huge miles per hours . the pro stock bikes had low et,s in the six nineties and mph gains too.
I don't know where all this came from but I'm sure I have always been led to believe:
"Dense Air" like we get often at the Pod increases power if the correct mixture is maintained
"Humid Air" sadly like we also get over here, decreases power as the water "grains" displace oxygen content in the air.
The air in Q3 (the quick session) at Gainesville was indeed very dense, (for the US anyway) the corrected altitude being around 900ft but also the air was relatively dry (17% humidity) making for record setting conditions.
My thoughts on the lack of power increase in the nitro classes...
1) Nitromethane releases a percentage of the oxygen it uses to burn from its own chemical breakdown, thus the percentage gains from density would be smaller than the gas or alcohol
2) Its ok having the good air but can you pump enough fuel through to keep the mixture rich enough to stop it going bang, or over-revving and dropping holes with the power increase, etc etc, if not... less blower drive surely? The nitro cars seem somewhat more of a balancing act to me.
3) If you make more power can you actually get it down to the track. Its been said that a good PS track is not a good Nitro track and vice versa
Where's Pi5ton when you need him?
PETE!!!???!!!
He's a man with proper answers!
Edited by theMighty on Tuesday 20th March 12:08
Edited by theMighty on Tuesday 20th March 12:10
Dense air just means that there is more oxygen, IE can put more fuel in and more power, with a fuel car this means they dont have to spin the blower as fast as they dont have to compensate for the extra air needed.
With an alky car the blower is there power, and is what we try to keep as constant as possible as it affects the tune up as the blower falls away during the event/season.
When its humid, yes there is water in the air and less oxygen so if a car was to run the same settings from say 1500ft to 3500ft the car would be very rich. when its humid fuel has to be taken away from the motor to get basic mixture right.
Also with nitro the actual % is affected by the temp of it.
Edited by BennettRacing on Tuesday 20th March 13:14
Yeah, humid air reduces power. High humidity means that the oxygen content of the air is being displaced by moisture, therefore there is less available oxygen to be ingested by the engine. This results in an overly rich mixture, so you have to pull fuel from the motor, and consequently, lose power.
Dense air is the complete opposite, and what was present in Florida during the Gatornationals. This means there was a very low moisture content in the air, thus meaning that the air being drawn in to the engines was packed with oxygen. More oxygen, more fuel, more go!
Your right about the nitro motors, they are less reliant on atmospheric conditions due to how potent the fuel is. They will suffer to a certain extent in humid conditions, as the blowers won't be able to build the same boost in the thinner air.
From what I saw on the ESPN coverage over here, you're exactly right about the lack of nitro performances. Whenever a big tune-up was tried out, it seems the cars either shook themselves apart, or put out cylinders. With the air being so good, no doubt a higher fuel load was added to them, which the plugs seemingly struggled to keep lit. I'm sure they must have a valid reason for not backing the overdrive off from the supercharger but I'm not entirely sure what it is, maybe they didn't want to risk too great a power loss?? And it looks like by pulling out enough fuel to keep the candles lit resulted in far too many lean (and expired!) engines, a la Schumacer in the final. For those that did manage to get the air and fuel sorted, it looked like this gave far too much power than the surface could handle, and a hell of a lot of tyreshake and smoke was the result for those.
Dense air is the complete opposite, and what was present in Florida during the Gatornationals. This means there was a very low moisture content in the air, thus meaning that the air being drawn in to the engines was packed with oxygen. More oxygen, more fuel, more go!
Your right about the nitro motors, they are less reliant on atmospheric conditions due to how potent the fuel is. They will suffer to a certain extent in humid conditions, as the blowers won't be able to build the same boost in the thinner air.
From what I saw on the ESPN coverage over here, you're exactly right about the lack of nitro performances. Whenever a big tune-up was tried out, it seems the cars either shook themselves apart, or put out cylinders. With the air being so good, no doubt a higher fuel load was added to them, which the plugs seemingly struggled to keep lit. I'm sure they must have a valid reason for not backing the overdrive off from the supercharger but I'm not entirely sure what it is, maybe they didn't want to risk too great a power loss?? And it looks like by pulling out enough fuel to keep the candles lit resulted in far too many lean (and expired!) engines, a la Schumacer in the final. For those that did manage to get the air and fuel sorted, it looked like this gave far too much power than the surface could handle, and a hell of a lot of tyreshake and smoke was the result for those.
As I understand it (and am probably wrong in saying it) - the increase in fuel has to be judged against several things, one being the ignition. More timing means more capacity for fuel combustion, but it also increases the output shaft speed.
A large amount of ignition may be applied at the hit to get the tyres to dig in, but within 40 feet this would have been reduced to counter for all manner of things happening to the chassis and engine (aero drag, tyre distortion etc).
Blower drive was, I thought most utilized at tracks such as Memphis when the ambient air was such that more mechanically forced air was required (since the NHRA relax the rules for the fuel classes). It may get backed off where conditions are cold (be it ambient temperature, or track heat).
With more fuel, as stated above, comes more air, but with this it needs more clutch. This is great assuming the track's in a condition to take it. Pro Stock cars I believe require a more greasy track as they make their power in the upper end of the rev range, i.e. if the motor can be spun up quickly into its power band, it will make power.
On the other hand, fuel classes seem to prefer more adhesive tracks, not because of the mechanical traction available itself, but the by-product of this, the loading it puts on the engine. This helps burn the fuel, hence make the power. From what I gather, it's all a balancing act.
As I think Luke mentioned, nitro itself will vary with temperature (68F I think is the temperature the NHRA check for 85%), but, if the conditions were right and you felt the need to, a nitro percentage of 100% is possible.
There's countless other areas which are fine tuned to eek out performance, including the use of the wheelie bar for aid or reduction of traction. Pete and others in the TF/FC circle will have more knowledge on this than I.
That's pretty much repeated all the posts above, but might have some useful points in it lol.
A large amount of ignition may be applied at the hit to get the tyres to dig in, but within 40 feet this would have been reduced to counter for all manner of things happening to the chassis and engine (aero drag, tyre distortion etc).
Blower drive was, I thought most utilized at tracks such as Memphis when the ambient air was such that more mechanically forced air was required (since the NHRA relax the rules for the fuel classes). It may get backed off where conditions are cold (be it ambient temperature, or track heat).
With more fuel, as stated above, comes more air, but with this it needs more clutch. This is great assuming the track's in a condition to take it. Pro Stock cars I believe require a more greasy track as they make their power in the upper end of the rev range, i.e. if the motor can be spun up quickly into its power band, it will make power.
On the other hand, fuel classes seem to prefer more adhesive tracks, not because of the mechanical traction available itself, but the by-product of this, the loading it puts on the engine. This helps burn the fuel, hence make the power. From what I gather, it's all a balancing act.
As I think Luke mentioned, nitro itself will vary with temperature (68F I think is the temperature the NHRA check for 85%), but, if the conditions were right and you felt the need to, a nitro percentage of 100% is possible.
There's countless other areas which are fine tuned to eek out performance, including the use of the wheelie bar for aid or reduction of traction. Pete and others in the TF/FC circle will have more knowledge on this than I.
That's pretty much repeated all the posts above, but might have some useful points in it lol.
Rat_Fink_67 said:
Yeah, humid air reduces power. High humidity means that the oxygen content of the air is being displaced by moisture, therefore there is less available oxygen to be ingested by the engine. This results in an overly rich mixture, so you have to pull fuel from the motor, and consequently, lose power.
Dense air is the complete opposite, and what was present in Florida during the Gatornationals. This means there was a very low moisture content in the air, thus meaning that the air being drawn in to the engines was packed with oxygen. More oxygen, more fuel, more go!
Your right about the nitro motors, they are less reliant on atmospheric conditions due to how potent the fuel is. They will suffer to a certain extent in humid conditions, as the blowers won't be able to build the same boost in the thinner air.
From what I saw on the ESPN coverage over here, you're exactly right about the lack of nitro performances. Whenever a big tune-up was tried out, it seems the cars either shook themselves apart, or put out cylinders. With the air being so good, no doubt a higher fuel load was added to them, which the plugs seemingly struggled to keep lit. I'm sure they must have a valid reason for not backing the overdrive off from the supercharger but I'm not entirely sure what it is, maybe they didn't want to risk too great a power loss?? And it looks like by pulling out enough fuel to keep the candles lit resulted in far too many lean (and expired!) engines, a la Schumacer in the final. For those that did manage to get the air and fuel sorted, it looked like this gave far too much power than the surface could handle, and a hell of a lot of tyreshake and smoke was the result for those.
Dense air is the complete opposite, and what was present in Florida during the Gatornationals. This means there was a very low moisture content in the air, thus meaning that the air being drawn in to the engines was packed with oxygen. More oxygen, more fuel, more go!
Your right about the nitro motors, they are less reliant on atmospheric conditions due to how potent the fuel is. They will suffer to a certain extent in humid conditions, as the blowers won't be able to build the same boost in the thinner air.
From what I saw on the ESPN coverage over here, you're exactly right about the lack of nitro performances. Whenever a big tune-up was tried out, it seems the cars either shook themselves apart, or put out cylinders. With the air being so good, no doubt a higher fuel load was added to them, which the plugs seemingly struggled to keep lit. I'm sure they must have a valid reason for not backing the overdrive off from the supercharger but I'm not entirely sure what it is, maybe they didn't want to risk too great a power loss?? And it looks like by pulling out enough fuel to keep the candles lit resulted in far too many lean (and expired!) engines, a la Schumacer in the final. For those that did manage to get the air and fuel sorted, it looked like this gave far too much power than the surface could handle, and a hell of a lot of tyreshake and smoke was the result for those.
I'd agree with everything except maybe that last line. To the best of my knowledge, tire shake is avoided by applying more power to keep the tires slipping longer. They want to stay BETWEEN shake and smoke.
All this makes you appreciate the tuners' abilities to balance all these variables. They say that this is what Alan Johnson is really good at. When he makes one change, he takes into account everything down to the downforce on the front wing. I thought just learning to compensate for one change in mechanical fuel injection on a bracket engine was complicated! Change one nozzle, effect the pressure on seven others.
As far as Greg Anderson is concerned, he emphasized a few years ago in an interview that what gave him his edge was testing his butt off. You could easily outspend him and still not get near him. How many more parts rules can they implement? LOL.
This is good talk. Thanks Guys.
Does anyone know of any websites chartrooms etc that talk like this most of the time?
Like a lot of us on here I want to know more about how you Guys make them work. Yes, we know it takes years of experience but to hear racers talking tech is music to my ears.
Does anyone know of any websites chartrooms etc that talk like this most of the time?
Like a lot of us on here I want to know more about how you Guys make them work. Yes, we know it takes years of experience but to hear racers talking tech is music to my ears.
Not so much on the modern stuff, but there's a couple of sticky threads on www.classicfunnycarboard.com titled "burned pistons" and "nitro tuneups" that are pretty informative. Pertaining to nitro itself, there's some interesting education at this link. www.fuelinjectionenterprises.com/ Just click on the "nitro notes" to the left.
Three of my all time favorite things ever seen on a message board were written by Frank Oglesby on classicfunnycarboard. They are
#1 "The best line about backsiding I ever head came from Larry Fullerton--I said how is it going Larry?---He replied "Well on the last run I backsided everything except the f###ing weight bar and I haven't check it yet"
#2 "I don't want to give the impression I have all the answers as the B*tch Goddess of Nitro has ways of humbling all of us at times---As the ACE one time told me "When you are on nothing matters and when your off nothing helps"
#3 "....and as my buddy Rapid Roy Harris used to say "There is more than one way to skin a cat BUT the cat don't like none of them"---Frank"
My interpretation of that last one is "There's more than one way to tune a nitro car, but the car don't like none of them!"
Three of my all time favorite things ever seen on a message board were written by Frank Oglesby on classicfunnycarboard. They are
#1 "The best line about backsiding I ever head came from Larry Fullerton--I said how is it going Larry?---He replied "Well on the last run I backsided everything except the f###ing weight bar and I haven't check it yet"
#2 "I don't want to give the impression I have all the answers as the B*tch Goddess of Nitro has ways of humbling all of us at times---As the ACE one time told me "When you are on nothing matters and when your off nothing helps"
#3 "....and as my buddy Rapid Roy Harris used to say "There is more than one way to skin a cat BUT the cat don't like none of them"---Frank"
My interpretation of that last one is "There's more than one way to tune a nitro car, but the car don't like none of them!"
Edited by nitrohaulic on Thursday 5th April 01:09
It highlights the big differences between modern and nostalgia nitro racing. Back in the good ol' days, a fuel system was straightforward, albeit you were tuning by sight, sound, smell and the number of torched pistons you created as a by-product.
Modern fuel systems are so complex now that there's no such thing as a self sufficient part. By that I mean the settings for one aspect of the engine can now, not remain un-changed i.e. any increase in fuel pressure, percentage, jet size has to be countered with clutch and ignition settings. Then there's things like varying rod lengths to alter individual cylinder compression etc.
In terms of my own car, the fuel system is as simple as it gets when it comes to blown nitro. Single pump, single mag, smallish blower and 16 fuel lines into the motor. #7 cylinder on a BBC can run quite lean under load hence some jetting changes have been implemented to resolve this, but on the whole, the tune-up is just a 95% cackle, lots of ignition and lots of clutch setup.
The truth is, no tune-up will run identically in any 2 cars, so a lot of it's down to what happens the 1st time the motor's fired, and the 1st 46.233 foot squirt down the track...
Modern fuel systems are so complex now that there's no such thing as a self sufficient part. By that I mean the settings for one aspect of the engine can now, not remain un-changed i.e. any increase in fuel pressure, percentage, jet size has to be countered with clutch and ignition settings. Then there's things like varying rod lengths to alter individual cylinder compression etc.
In terms of my own car, the fuel system is as simple as it gets when it comes to blown nitro. Single pump, single mag, smallish blower and 16 fuel lines into the motor. #7 cylinder on a BBC can run quite lean under load hence some jetting changes have been implemented to resolve this, but on the whole, the tune-up is just a 95% cackle, lots of ignition and lots of clutch setup.
The truth is, no tune-up will run identically in any 2 cars, so a lot of it's down to what happens the 1st time the motor's fired, and the 1st 46.233 foot squirt down the track...
Nitro-Besty said:
In terms of my own car, the fuel system is as simple as it gets when it comes to blown nitro. Single pump, single mag, smallish blower and 16 fuel lines into the motor. #7 cylinder on a BBC can run quite lean under load hence some jetting changes have been implemented to resolve this
What do you have in the way of returns?
Idle check valve, hi speed, any others?
As we are running normally aspirated we can tune each cylinder completely individually but at the minute all ports are equal as we have no reason to do otherwise.
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