I wasn't directing my comment to anyone or any specific car. It was a general statement.
I’m not much into dyno numbers.
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rmchrgr
Skate And Destroy
OK, but... in a round about way, you did ask for proof?
It's all good, I'm just providing food for thought in response to what you said. I know some people get hung up on the idea that 'we don't race dynos' and all, especially John who started this thread, he beats that idea like a rented mule. It's OK to acknowledge an impressive achievement though even if it does not necessarily prove anything specific.
On the other hand, an impressive dyno number obviously does not mean that real-world tuning experience is any less important. You have to understand the numbers for them to be useful. I think that's where skepticism about dyno numbers comes from because they don't always translate to better ETs. Plain and simple it takes experience to be able to harness the info in a productive way.
But the underlying point here is that as we all know, a dyno sheet is just a tool. It's an established baseline conducted under optimal circumstances that is ultimately used for tuning in real-world situations that may not be so optimal. The tuning choices you make when using that info is reflected in time slips. No one complains about racers using weather stations but they are similar to a dyno sheet in that they provide helpful information to aid in making more informed tuning choices under specific circumstances.
Posting dyno numbers often seems to get interpreted as to whether the engine build was successful or not. While that's mostly true, it's not the whole story. Dyno sheets don't only show power output but specifically how the engine uses fuel and timing plus all sorts of other myriad data that can help the tuner make choices when trying to get the car do one thing or another. Why would you reject that kind of info outright? Knowledge is power, always.
Regardless, the F.A.S.T. cars are really amazing in that they are over-the-top, factory-correct restorations with stock 'looking' engines making close to 1,000 horsepower. If you're not impressed by that then you might have unrealistic standards.
Does not get much cooler than a stock-looking '71 Cuda going mid nines at 145 mph on 7" Polyglas GT tires...
No, I didn't. As I said I made a general statement. I can say the slant 6 in Vixen has 550HP. It's all bullshit until there's proof.
MopaR&D
Nerd Member
Awesome video! Neat thing about hub dynos, since the dyno is connected in-line with the drive axles there is no risk of the vehicle "falling off" the dyno (driving off the rollers) and it doesn't need to be strapped down. That's why you are able to see the car lift up just like it would if it was launching at the strip. A neat benefit of that is you can watch the chassis and suspension and see how it handles the power, to some extent... still no reaction forces being applied forward but you can see the reaction torque on the driveline and chassis doing its thing.
rmchrgr
Skate And Destroy
No tire slip either which can happen on a chassis dyno.
justinp61
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So, the Cuda running in the 9's isn't proof?
Did you see me say that? Are yall just trying to be assholes? You're workin real hard at it. I said with no dragstrip, there's no proof. I've also said this makes THREE TIMES NOW I was not talking about ANY specific car. Now go be a fuckhead somewhere else.
LocuMob
Fluid Technician
I knew what ya meant Rusty.
These F.A.S.T. cars are amazing. I saw some in their infancy at the Mopar Nationals, I think it was Dudek's Road Runner(?) and they were tinkering trying to get every little bit of power out of that car. I don't remember the times, but they were faster than most people in the stands expected.
I doubt I'll ever need or get to use a dyno, but it would be fun to do so, so much information to be had. There was a dyno place near where I delivered parts too, shook the building when the big boys showed up with their toys. Sadly, they didn't last long.
These F.A.S.T. cars are amazing. I saw some in their infancy at the Mopar Nationals, I think it was Dudek's Road Runner(?) and they were tinkering trying to get every little bit of power out of that car. I don't remember the times, but they were faster than most people in the stands expected.
I doubt I'll ever need or get to use a dyno, but it would be fun to do so, so much information to be had. There was a dyno place near where I delivered parts too, shook the building when the big boys showed up with their toys. Sadly, they didn't last long.
Thanks. It's incredible how people cram words down your mouth around here. I take nothing away from anyone's car. I was basically agreeing with John in his original post. Dyno numbers in and of themselves mean nothing, since I can take my car to a different dyno across town and get completely different measurements. So, that to me, is bench racing fodder. The drag strip is the proof in the pudding. It's like these Chevy guys saying their smooth idling 327 with a Rochester 4 jet makes 500HP. lol You can "say" your engine makes whatever.
justinp61
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lead69
hopeless car junkie
Agree with you, that's why I cannot wait to back up my dyno numbers with a time slip. A dyno is just a measuring tool no different than a flow bench and the accuracy is dependent upon the operator and the quality of the machine. To me where these tools shine is in seeing the before and after results of the changes made, regardless of the accuracy of peak numbers you can see improvement or regression. I could have never found the 30hp hidden in the timing curve of my engine if it wasn't for the dyno. It was ran with locked timing first then the timing was checked every 1k rpm to figure a curve out and it was not a conventional one. I would have never found that at the track, it would have been put some timing in help the 60/hurt the big end or vice versa and not nailing down the specific rpm range where the engine wanted timing and did not. There are some reasons as to why mine wanted such a specific timing curve but again the only reason I learned about it was from the dyno. Knowing that it makes sense these guys use a dyno to wring every last ounce out of a non conventional mixture of parts to make max hp. I got by without dyno time for years and to be honest the only reason I have it now is because I am an owner of the thing, it is definitely a blast and a wealth of knowledge.
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aaronk785
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Makes me wonder what Ray can actually get out of a set of factory heads.
Does he do them
aaronk785
Well-Known Member
PBR. I don't know for sure. I guess I just assumed. I know he has in the past.
Between 700 and 1050 give or take a little.
The real question is do you really care? You have the proof!
Well if you tell a Dyno operator to make the numbers lie which isn't all that easy since most dynos have some set parameters for correction factors a dynos numbers are accurate as in what is printed off of the computer is what it actually has unless like you say "you can say your slant 6 has 550 HP" lol .
A Dyno is also not bench racing either it is a tuning tool to get every last bit out of an engine.
Dial in your air- fuel, dial in your timing, do testing, like figuring out what your engine likes for lash, everything you can test and get real data, compared to guessing or testing at the track where you might get 2 runs to see if a change made an improvement a day or maybe blow the thing up, I can't imagine buying a torque converter on a guess at $ 1000.00 or more. But if a engine like mine gets put in a **** car it still has what the dyno numbers say it's just in a **** car. It's not the dynos fault or lying
It's like guys who are hooked on flow bench numbers, put a head that flows 400cfm on some junk **** short block, it will be dog *** slow...it's not the heads fault or lying flow numbers.
I'm sure you already know all this though.
Well, It's not about telling the dyno operator to lie. That's not what I meant. What I mean is, one dyno can say one thing and another something completely different, so those numbers are really irrelevant. With dyno sheets, all you have are pieces of paper. It's sorta like when someone issues a protective order. As they say, "they aren't worth the paper they're written on". The dyno info is only half the picture. The drag strip is the other half. Without the drag strip, all you have is a piece of (expensive) paper.
A dyno tune isn’t always a good track tune. Two different worlds.
And that's yet one MORE variable.
If you've been around badass engines enough you can tell if it's badass or just irrelevant pieces of paper. You might be right if there's factors involved like elevation but if the correction factors are identical between 2 dynos the numbers will not be far off. I don't disagree with you about the drag strip . I'm lucky I don't have to pay for dyno time. But if I did after what I know then I would gladly pay to know where my engine is at it's happiest and not having to guess on gears and converter
If you're using a dyno just to get a piece of paper with a number on it you're not using the dyno to it's full potential.
Absolutely but with the correction factors you'll have a very very close baseline and there's a fairly heavy load on a dynos brake to simulate the load at the track, not perfect but much better than guessing
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