GM's TRUE 'Golden Age'....an opinion

[OVERKILL]

Originally Posted By: Duffman77

Even worse your trying to race a math formula.


And you are trying to race what here, a legacy? I'll take math over heartstrings any day. Have you ever actually drag raced? I'm thinking no........

I'm FAR from a hardcore dragracer. I've only been to the track a maybe a handful or so times. But I've seen enough timeslips, done enough of my own modding and talked to enough guys who race to know quite well as to the relationship between power and trap speed.


Quote:
The problem with your formula is it breaks horsepower to one dimension. We are not talking racing CVTs here. For 99.9% of engines Horsepower is a function of RPM. Your formula doesn't account for transmission gear ratios or final drives.


It doesn't need to. Those affect ET. Again, you obviously don't drag race. I cut awesome MPH's and awful ET's because I had the stock 3.08 gears in the car. Some 3.73's or 4.10's would have caused my ET to plummet, but my MPH would have stayed the same. A good friend of mine had an '89 notch that couldn't run my MPH if its life depended on it. The engine just wasn't as healthy. But he ET'd better than me (high 13's) because he had 3.73's out back.

Quote:
The 283hp Fuelie had the "Duntov cam", meaning its likely a more peaky engine than the one that was sold in 90's mustangs which would require more drive ability for the masses. There us no doubt in my mind that the 302 HO has more area under the curve.


There's no doubt in my mind the 302HO made more power everywhere. It also made more torque. It was a 30 year newer roller engine, so it shouldn't be surprising

Look at the freakin' LS1!!

Quote:
Again compare 14.3 @ 100 mph to other cars of the musclecar era, some of them with net ratings. Even though the vette at 2800 (+200 driver = 3000 lbs) is a very light car, there is no way its turning those times with 217 hp net.


And why not?

Quote:
I checked a different book of mine and it quotes a Car Life Magazine test of a 1969 Boss 429 at 14.09 @ 102.85 mph. Similar mph, I guess it only has 3800/3000 x 217 = 275 ish Net horsepower as well?


Yup. There were two versions of the BOSS 429. The first run had a tiny baby camshaft that neutered the car. 275HP is probably about right for that one. The 2nd run had a larger SFT stick in it and was a lot faster, and trapped a lot higher.

 

[Duffman77]

Wow way to play the arrogance card, you have no knowledge of my automotive pedigree or what or who I have been around. Just because you have 2x as many passes under your belt at the dragstrip you must be right. You know what I'll raise you one mechanical engineering degree, I spent years in school measuring actual lab results vs calculated results and have learned that mathematical models have limits to their application. If you allow for even 10% error between your 217 which you are so stuck on, you get 217 + 21.7 = 238.7 which is very close to the 240 I think it probably had. Your entire premise is also based on the fact that the factory numbers couldn't have been under rated which we clearly know never happened in the history of performance cars...

Nowhere have I said that MPH could not be an estimate of engine HP, I have said it is just that, an estimate that can be flawed.

 

[OVERKILL]

Originally Posted By: Duffman77
Wow way to play the arrogance card, you have no knowledge of my automotive pedigree or what or who I have been around. Just because you have 2x as many passes under your belt at the dragstrip you must be right. You know what I'll raise you one mechanical engineering degree, I spent years in school measuring actual lab results vs calculated results and have learned that mathematical models have limits to their application. If you allow for even 10% error between your 217 which you are so stuck on, you get 217 + 21.7 = 238.7 which is very close to the 240 I think it probably had. Your entire premise is also based on the fact that the factory numbers couldn't have been under rated which we clearly know never happened in the history of performance cars...

Nowhere have I said that MPH could not be an estimate of engine HP, I have said it is just that, an estimate that can be flawed.


Oh come on, are we going to post IQ scores next? You really don't need to get this wound up.

Let's go back a few steps here:

What is a dynometer? What does it measure?

What effect do operating conditions have on the results?

What other variables that were allowed to exist in the testing over the years played into how those numbers were obtained?

I grew up around Engineers, there are many on this board, I consider them good company. My great grandfather was one of the foremost pioneers in hydroelectricity. Does that have any relevance to this topic? Nope. But I mean, if we are credential dropping, which you appear to be doing here, I have a pretty broad background myself. I pursued computers, but that doesn't make my experience or education any less relevant.

But back on topic: My point about time at the dragstrip was not to demean you or make you feel like I was attacking your ego. It also wasn't meant to be an exercise in arrogance. It was a point about what you'd observe about various combinations and what group of parts making a certain amount of power would run in a given configuration if you spent more time there. My platform of experience is the Fox Mustang, I'm pretty familiar with it, and have spent, and still spend a great deal of time talking with friends and acquaintances who race them.

In the dragracing world, and in its most basic form, the general premise here is that MPH is how much power you are making, ET is how effectively you put it to the ground.

So you mention HP, where we are measuring torque at RPM, that is all HP is. The rate at which work can be performed. We can use a dyno and "measure" this, but those results vary. Change the barometric pressure, change the altitude, change any of those the MANY variables and the results change.... often significantly.

Now what is neat here is that those same variables have that effect at the track on MPH

SteveSRT8 spends a great deal of time at the strip and has posted the same thing I have in this thread.

Now, if we want to delve into this further, the 217HP number, which I am definitely not stuck on, is simply a 30% reduction over the SAE GROSS value. It wasn't meant to be regarded as some sort of steadfast reference point. The SAE GROSS values were far from accurate, I think we can agree here no?

So then the part we appear to be hanging up on is the weight and power to run a given MPH thing.

Let me get this out of the way: I don't care if GM claimed it made 4,000HP or 40HP. The SAE GROSS numbers are next to useless. So all we have is the car's weight and what it cut for MPH stock to go by. And that's what I based my comparison of the 30%-derived figure on, using a known reference point: My own car.

If the '60 Corvette made 240HP, with its weight, it would have trapped higher than my car, that is my logic here. And it didn't.

Now, the '93 Cobra made 235HP, weighed 3,255lbs and ran 14.3@98Mph stock (using a magazine example). Other examples cite up to 101Mph traps for this car. It has 200lbs on the Corvette. That puts the Corvette again around the 215-220HP range.

I'm REALLY not trying to be an [censored] here, though I'm sure it seems that way, so I apologize if I've come across as crass or rude, as that was not my intent. I'm enjoying this debate, so if you'd like to continue it in a civilized manner, we can certainly do so.

 

[Spazdog]

I used to run my Kawasaki at the strip virtually every weekend they were open. I don't know how many passes. I don't really work on the math end of it. I guess that makes me less of a racer. Maybe that makes me more of a rider and less of a crew chief.

The old guys would chide me for some things I did; you know you lost some of your trap speed by deep staging like that..."
I was just doing it because "Vanilla Ice" in his 5.0 would only light the pre-stage. So I turned out my pre-stage lights. I beat him by two seconds. (Why do you car guys do that? Freakin' stage already!)

They also calculated my horsepower at something like 68whp...

But I never lost to a street driven Fox Mustang 5.0 and this was late '80s-early '90s. There were plenty of Mustangs to race. (and 1/8th mile Texas Raceway would allow the bikes to run against anyone fool enough to try us at the time)

 

[OVERKILL]

Originally Posted By: Spazdog

I used to run my Kawasaki at the strip virtually every weekend they were open. I don't know how many passes. I don't really work on the math end of it. I guess that makes me less of a racer. Maybe that makes me more of a rider and less of a crew chief.

The old guys would chide me for some things I did; you know you lost some of your trap speed by deep staging like that..."
I was just doing it because "Vanilla Ice" in his 5.0 would only light the pre-stage. So I turned out my pre-stage lights. I beat him by two seconds. (Why do you car guys do that? Freakin' stage already!)

They also calculated my horsepower at something like 68whp...

But I never lost to a street driven Fox Mustang 5.0 and this was late '80s-early '90s. There were plenty of Mustangs to race. (and 1/8th mile Texas Raceway would allow the bikes to run against anyone fool enough to try us at the time)


Yeah, bikes are something else

IIRC, there was a light guy that was able to pilot a stock V-MAX to a 9-second pass

 

[mechanicx]

I agree with Duffman, Overk1ll there is a flaw in your logic. First you agree mph is an accurate pedictor of net HP. The calculators say the '57 had about 240 HP based on the best info of at least 3000-3100lbs wt and 99-100 mph. Then you say your mustang was heavier and ran the same speed with 225 hp rating. Which is correct the calculator or your Mustang's net rating and weight? The calculator was developed from many vehicles so I don't see why your one Mustang example should take precedence and be the standard.

Besides that net ratings and hp predictors aren't 100% and there's probaly up to 10% variance and within the dispute of 217 hp vs 240 hp. Also it's already been mention that 5.0 HO with more displacement and long intake runners probably has more area under the curve. That goes back to the ~10% variance and further suggests the 'vette had 240 HP net like the calculators predict.

 

[mechanicx]

Originally Posted By: Spazdog

I used to run my Kawasaki at the strip virtually every weekend they were open. I don't know how many passes. I don't really work on the math end of it. I guess that makes me less of a racer. Maybe that makes me more of a rider and less of a crew chief.

The old guys would chide me for some things I did; you know you lost some of your trap speed by deep staging like that..."
I was just doing it because "Vanilla Ice" in his 5.0 would only light the pre-stage. So I turned out my pre-stage lights. I beat him by two seconds. (Why do you car guys do that? Freakin' stage already!)

They also calculated my horsepower at something like 68whp...

But I never lost to a street driven Fox Mustang 5.0 and this was late '80s-early '90s. There were plenty of Mustangs to race. (and 1/8th mile Texas Raceway would allow the bikes to run against anyone fool enough to try us at the time)


Easy for them to critisize someone on two wheels. I can't launch a motorcycle that quick. I'm still an inexperienced rider. I'm not saying you can't, but that let's see those guys do it better lol.

 

[Duffman77]

Originally Posted By: OVERK1LL

Oh come on, are we going to post IQ scores next? You really don't need to get this wound up.

Let's go back a few steps here:

What is a dynometer? What does it measure?

What effect do operating conditions have on the results?

What other variables that were allowed to exist in the testing over the years played into how those numbers were obtained?

I grew up around Engineers, there are many on this board, I consider them good company. My great grandfather was one of the foremost pioneers in hydroelectricity. Does that have any relevance to this topic? Nope. But I mean, if we are credential dropping, which you appear to be doing here, I have a pretty broad background myself. I pursued computers, but that doesn't make my experience or education any less relevant.

But back on topic: My point about time at the dragstrip was not to demean you or make you feel like I was attacking your ego. It also wasn't meant to be an exercise in arrogance. It was a point about what you'd observe about various combinations and what group of parts making a certain amount of power would run in a given configuration if you spent more time there. My platform of experience is the Fox Mustang, I'm pretty familiar with it, and have spent, and still spend a great deal of time talking with friends and acquaintances who race them.

In the dragracing world, and in its most basic form, the general premise here is that MPH is how much power you are making, ET is how effectively you put it to the ground.

So you mention HP, where we are measuring torque at RPM, that is all HP is. The rate at which work can be performed. We can use a dyno and "measure" this, but those results vary. Change the barometric pressure, change the altitude, change any of those the MANY variables and the results change.... often significantly.

Now what is neat here is that those same variables have that effect at the track on MPH

SteveSRT8 spends a great deal of time at the strip and has posted the same thing I have in this thread.

Now, if we want to delve into this further, the 217HP number, which I am definitely not stuck on, is simply a 30% reduction over the SAE GROSS value. It wasn't meant to be regarded as some sort of steadfast reference point. The SAE GROSS values were far from accurate, I think we can agree here no?

So then the part we appear to be hanging up on is the weight and power to run a given MPH thing.

Let me get this out of the way: I don't care if GM claimed it made 4,000HP or 40HP. The SAE GROSS numbers are next to useless. So all we have is the car's weight and what it cut for MPH stock to go by. And that's what I based my comparison of the 30%-derived figure on, using a known reference point: My own car.

If the '60 Corvette made 240HP, with its weight, it would have trapped higher than my car, that is my logic here. And it didn't.

Now, the '93 Cobra made 235HP, weighed 3,255lbs and ran 14.3@98Mph stock (using a magazine example). Other examples cite up to 101Mph traps for this car. It has 200lbs on the Corvette. That puts the Corvette again around the 215-220HP range.

I'm REALLY not trying to be an [censored] here, though I'm sure it seems that way, so I apologize if I've come across as crass or rude, as that was not my intent. I'm enjoying this debate, so if you'd like to continue it in a civilized manner, we can certainly do so.


My credentials are indeed relevant to this topic but 99% of the time I choose to not introduce them because I am not here bully people into accepting my point of view. I am here to learn and exchange ideas from people who bring knowledge from other disciplines of expertise and those with practical experience. So that said, were cool.

I wouldn't say that SAE Gross is inaccurate, its just a different system of measurement that accounts for less variables and is therefor less relevant but not irrelevant.

The argument I am trying to form is that a 14.3 was a very impressive 1/4 mile up until about 5 years ago (when modern factory HP started getting crazy). From the experience I have gained both driving and as a passenger in a multitude of vehicles combined with years of reading books and magazine articles (I have a pretty massive automotive library) that quote actual track times from the day vs quoted HP numbers, putting the 57 vette at 217 net is just selling it short, especially considering how brutal the tires the car had in the day. The second angle that leads me to believe this was the engine had the best cylinder head and best induction system Chevrolet had in 1957 and the Duntov cam was a really a racing cam for its day, to say that a racing engine could only form 220 net is again selling it short even for 1957. I am not saying it is a powerhouse by todays standards but given its displacement it was up until the early 90s for a stock automobile outside of the exotics (both foreign and domestic).

As I see it, the distance between us is you believe that an 87 5.0 was only good for 225 net. I think you are selling the 5.0 short, Ford didn't de-rate the engine when it went from speed density to MAF, and from everything I have read the speed density cars were the ones to have. I've also read that a small bump in initial timing does wonders for this engine, Ford's way of under rating it yet leaving something in it for those who were ambitions enough to take it. You have admitted there were some freak 5.0s that ran outstanding times, no way those cars were 225 net.

 

[Duffman77]

To propose a little real world experiment for those who have a manual transmission and frequent the track. Take one standard run and then the next run shift 1-2-4 and see if it impacts your MPH.

 

[Duffman77]

Originally Posted By: dailydriver
Originally Posted By: SteveSRT8
You can sure tell the people who do not spend much time at the strip!

Pure and simple, trap speed is the LEAST affected by driver and strip conditions, etc. ET is extremely tightly tied to the launch. Example: a tenth off your 60 foot time almost always gets you TWO tenths on the big end.

Simple version: ET is very driver dependent, trap speed is not.


ABSOLUTELY!!!!!^^^^

In fact, sometimes you will have a higher trap speed because you launched/60'ed/or the track was prepped poorly!


But can you tell me why an ET will be lower with a lower trap speed and how you can have a higher speed with wheel spin?

 

[addyguy]

This thread sure did take some weird turns, didn't it?

 

[OVERKILL]

Originally Posted By: mechanicx
I agree with Duffman, Overk1ll there is a flaw in your logic. First you agree mph is an accurate pedictor of net HP. The calculators say the '57 had about 240 HP based on the best info of at least 3000-3100lbs wt and 99-100 mph. Then you say your mustang was heavier and ran the same speed with 225 hp rating. Which is correct the calculator or your Mustang's net rating and weight? The calculator was developed from many vehicles so I don't see why your one Mustang example should take precedence and be the standard.

Besides that net ratings and hp predictors aren't 100% and there's probaly up to 10% variance and within the dispute of 217 hp vs 240 hp. Also it's already been mention that 5.0 HO with more displacement and long intake runners probably has more area under the curve. That goes back to the ~10% variance and further suggests the 'vette had 240 HP net like the calculators predict.


mechanicx, I'm not using a calculator, I'm using my car, and other Fox Mustangs, which I have seen the dyno data for, as well as the factory data for, as a reference point.

If you have a calculator you are using, would you mind sharing the link please?

And I agree with your last statement in regarding ratings and predictors not being 100%. But then neither are dyno's. They are only accurate for that single pull. Pull that engine again, you will get a different number.

The 302HO certainly had more area under the curve, I haven't argued to the contrary, but I still think 240HP is too high for the 283 fuelie.

We are arguing about 20-25HP here, which I know seems silly, but that's a few MPH when you run 14's.

 

[SteveSRT8]

Originally Posted By: Duffman77
But can you tell me why an ET will be lower with a lower trap speed and how you can have a higher speed with wheel spin?


Nope, I cannot. But I can tell you that I have many, many passes at the strip across 40 years in a ton of different cars and trucks.

ANY time I get a low ET the trap speed is lower than when I get a higher ET! Muff the launch, light the tires, and most times you get the best trap speed you ever saw!

My sig time is quicker than the allegedly fastest stock SRT8 in the country on real street tires. But I know two cars with higher ET's that actually have higher trap speeds.

You're the engineer, you tell me!

 

[SwampSurvivor]

While I don't think I have any particular brand loyalty, my favorite "era" of GM was when they made the following vehicles at the same time:

 

[OVERKILL]

Originally Posted By: Duffman77

My credentials are indeed relevant to this topic but 99% of the time I choose to not introduce them because I am not here bully people into accepting my point of view. I am here to learn and exchange ideas from people who bring knowledge from other disciplines of expertise and those with practical experience. So that said, were cool.

I wouldn't say that SAE Gross is inaccurate, its just a different system of measurement that accounts for less variables and is therefor less relevant but not irrelevant.

The argument I am trying to form is that a 14.3 was a very impressive 1/4 mile up until about 5 years ago (when modern factory HP started getting crazy). From the experience I have gained both driving and as a passenger in a multitude of vehicles combined with years of reading books and magazine articles (I have a pretty massive automotive library) that quote actual track times from the day vs quoted HP numbers, putting the 57 vette at 217 net is just selling it short, especially considering how brutal the tires the car had in the day. The second angle that leads me to believe this was the engine had the best cylinder head and best induction system Chevrolet had in 1957 and the Duntov cam was a really a racing cam for its day, to say that a racing engine could only form 220 net is again selling it short even for 1957. I am not saying it is a powerhouse by todays standards but given its displacement it was up until the early 90s for a stock automobile outside of the exotics (both foreign and domestic).

As I see it, the distance between us is you believe that an 87 5.0 was only good for 225 net. I think you are selling the 5.0 short, Ford didn't de-rate the engine when it went from speed density to MAF, and from everything I have read the speed density cars were the ones to have. I've also read that a small bump in initial timing does wonders for this engine, Ford's way of under rating it yet leaving something in it for those who were ambitions enough to take it. You have admitted there were some freak 5.0s that ran outstanding times, no way those cars were 225 net.


While I see your point(s), and don't necessarily disagree with them or what you are saying, I would like to introduce the following:

-You mentioned the BOSS 429 earlier and thought that the idea that it could only have 270HP SAE NET was absurd. I didn't find it absurd at all. While it had toilets for cylinder heads, Ford intentionally crippled it with a puny carb and baby HFT camshaft.

Enough people complained that the car was a turd that Ford put a larger carb and larger SFT camshaft in it midway through the production run. The results were a car that ran 13's on the poo poo tires it had.

They did a really nice special on BONE STOCK Muscle cars on Dream Car Garage many years ago:

0-60 and braking:


1/4 mile (part 2, shows the BOSS 429 and the final results):


BOSS 429 ran [email protected]. Not impressive right? even funnier was that it was the fastest car tested

Remember, these are BONE STOCK cars, right down to the rubber. Like you mentioned with the Fox, yes, the 302HO woke up with the timing bumped a little. The same was the case for many of the cars from that era. A few small tweaks resulted in a HUGE power increase. The TASCA Super BOSS ran bottom 10's on street tires with the larger cube 494ci BOSS 429 CAN-AM engine. Same heads, bigger intake and carb. And it is unfortunate (for me) that you mention the timing thing because I had forgotten that I was running 14 degrees initial at that point, which invalidates part of my argument a bit.

But even if we say my car was making 235-240HP with the timing bump and that it was one of the "ringers", that still only puts the 'vette at 220-225HP

But you bring up a good point about "ringers" that I touched upon earlier, and that is that no car is the same. So there indeed likely were 283 fuelie cars making 240HP that would have cut higher traps. And at the same time, there would have been 215HP ones that cut lower ones. There's no doubt in my mind about that.

 

[IndyIan]

Quote:
Originally Posted By: SteveSRT8
Nope, I cannot. But I can tell you that I have many, many passes at the strip across 40 years in a ton of different cars and trucks.

ANY time I get a low ET the trap speed is lower than when I get a higher ET! Muff the launch, light the tires, and most times you get the best trap speed you ever saw!

My sig time is quicker than the allegedly fastest stock SRT8 in the country on real street tires. But I know two cars with higher ET's that actually have higher trap speeds.

You're the engineer, you tell me!
I'm not an engineer but I'll have a guess that some wheelspin (at the line) stores some rotational energy in the driveline? So when the car hooks up again you get some of that energy back which results in a higher speed closer to the start than a proper run gives you. So it takes far longer to get to 60', but the car might be moving sligtly faster at 60', but never enough to make up for the extra time.
An interesting experiment would be to start with the tires lit up already, especially with a low hp, high traction vehicle. That might give a higher top speed too.

 

[SteveSRT8]

Originally Posted By: OVERK1LL
But you bring up a good point about "ringers" that I touched upon earlier, and that is that no car is the same. So there indeed likely were 283 fuelie cars making 240HP that would have cut higher traps. And at the same time, there would have been 215HP ones that cut lower ones. There's no doubt in my mind about that.


It's good to point this out. The production variations were HUGE in the 60's and 70's, with big differences between similar cars as far as performance goes.

 

[morris]

"Help me out. What were the Chrysler "dogs" of the '50s-'60s?"
would you realy drive a 1961 plymounth wagon?

 

[morris]

if your chevy is so great go to a NHRA race and run in SS/AH.

 

[Duffman77]

Originally Posted By: SteveSRT8
Originally Posted By: Duffman77
But can you tell me why an ET will be lower with a lower trap speed and how you can have a higher speed with wheel spin?


Nope, I cannot. But I can tell you that I have many, many passes at the strip across 40 years in a ton of different cars and trucks.

ANY time I get a low ET the trap speed is lower than when I get a higher ET! Muff the launch, light the tires, and most times you get the best trap speed you ever saw!

My sig time is quicker than the allegedly fastest stock SRT8 in the country on real street tires. But I know two cars with higher ET's that actually have higher trap speeds.

You're the engineer, you tell me!


This would only apply in a situation where you have mild tirespin, not where you spin them so fast the engine runs away. The point that IndyIan brings up is half the answer in the that the driveline is storing kinetic energy that is indeed returned at a point farther down the track, that allows the car to Mph the same. Also as long as you are operating in the region below peak horsepower your engine always makes more power as the RPM climbs so your car is generating more power while the tires are spinning and the driveline is storing the energy until the car re hooks. Since your car has generated more power with spinning it is actually possible to MPH higher.

To understand why a car that is perfectly launched has a better ET than the example above which has put more power to the track you have to draw the distinction that drag racing is about racing position and not about racing velocity (like taking 0-60 time trials) which I know you already know. If you have taken a class in calculus you will know that the integral of an acceleration plot will give you velocity and the integral of a velocity plot gives you position (distance). It is advantageous to obtain more accelleration sooner because that initail burst in velocity is sustained for the remainder of the time of the pass. I thought about this for a while and I'll post a graphical example tomorow that illustrates this fairly well if I have time.