Brainstormin' 440 vs 5.9 ...

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What we do know is some have found some pretty notable differences in the measurements from dyno to dyno. That doesn't happen with Wallace
What do you mean? Wallace isn't measuring horsepower it's calculating horse power under an exact set of perimeters. If your vehicle doesn't run the number how do you know if it is because the hp measured at the dyno is wrong or that you are not operating under the same perimeters that Wallace used to calculate how much power it should have? Or if it is some combination of both the dyno and the perimeters being off.
 
In my mind, if a engine dyno's 450 HP, and it's installed in a XXXX weight of car, and runs a MPH that shows 350 HP, I raise my eyebrows because a 100 hp loss is a lot. A LOT !!! Just say'n
Yet another scenario. Same motor, same car. Give the car to a novice drag racer and see what the et is. Now turn the car over to a championship winning team and driver and with no changes to the hp of the motor see how much the et is improved. How does the Wallace calculator account for that?
 
Another scenario. If you put the same motor that dynos *** hp in two different vehicles that weigh the same one is a pickup and one is a duster what is the chance that they both will run the same et?
I've actually taken track proven ET 340 and done the truck/duster deal. I can tell you, the truck was slower :)
 
Yet another scenario. Same motor, same car. Give the car to a novice drag racer and see what the et is. Now turn the car over to a championship winning team and driver and with no changes to the hp of the motor see how much the et is improved. How does the Wallace calculator account for that?
It's why I like to throw out the ET when using wallace. Easier to skewer the ET than the MPH
 

Is wind the only variable unaccounted for? Wind is not a variable on a dyno.
Without using an 'extreme" case, then not a whole lot will effect the MPH. ET, yes. But not MPH so much. If you noticed, Joe talked about "body twist, slicks wrinkling, chirp of a tire, etc.". However, that won't affect the MPH hardly any, if at all. It's why I use the weight x MPH. Wallace is "at the crank", not "at the wheel". At least what I use.
 
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Without using an 'extreme" case, then not a whole lot will effect the MPH. ET, yes. But not MPH so much. If you noticed, Joe talked about "body twist, slicks wrinkling, chirp of a tire, etc". However, that won't affect the MPH hardly any, if at all. Wallace is "at the crank", not "at the wheel". At least what I used.
Is it possible that the reason Joe's not running his mph because the motor is not making the same horsepower at the track that it was at the dyno?
 
Is it possible that the reason Joe's not running his mph because the motor is not making the same horsepower at the track that it was at the dyno?
I'll just say something goes without say'n. 3665 at the start line, 9.5 PTC, 4.10 gears, slicks. Dyno says 500. Wallace says 375. Both at the crank. 87 MPH. Use common sense and tell me which one is closest to actual horsepower. Tell me what you think.
 
I'll just say something goes without say'n. 3665 at the start line, 9.5 PTC, 4.10 gears, slicks. Dyno says 500. Wallace says 375. Both at the crank. 87 MPH. Use common sense and tell me which one is closest to actual horsepower. Tell me what you think.
Take the motor to another dyno and it also says 500 hp. Now what do you think?
 
Take the motor to another dyno and it also says 500 hp. Now what do you think?
You didn't answer. Which one is closest by common sense. I gave the facts of the truck you need. Does it take 500 hp to run 87 with that combo of weight/stall/gear/slicks ??
 
I'll just say something goes without say'n. 3665 at the start line, 9.5 PTC, 4.10 gears, slicks. Dyno says 500. Wallace says 375. Both at the crank. 87 MPH. Use common sense and tell me which one is closest to actual horsepower. Tell me what you think.

Take the motor to another dyno and it also says 500 hp. Now what do you think?

You didn't answer. Which one is closest by common sense. I gave the facts of the truck you need. Does it take 500 hp to run 87 with that combo of weight/stall/gear/slicks ??
Answer ??? Anyone ???
 
I think the biggest factor there is Joes lunch break truck probably could make use of some 4.30 or 4.56 gears as well. Use your Wallace gear calculator and plug in the et & mile an hour it should be running at that weight.
 
I think the biggest factor there is Joes lunch break truck probably could make use of some 4.30 or 4.56 gears as well. Use your Wallace gear calculator and plug in the et & mile an hour it should be running at that weight.
I agree, more converter and gear for the 1/8th. It will go quicker, but I doubt it would change mph. I gave my Duster more gear and converter and lost mph in the 1/4. engine ran out of lungs. just say'n.
 
Man I love this stuff.
It’s all physics
Energy(HP) = Velocity (mph)squared x Mass(weight pounds)
So using the formula the MPH will take x amount of power to achieve. The engine may make more horsepower than the MPH indicates but it cannot make less HP than the MPH indicates.
With that being said a 375 HP engine may be as fast as a 500 HP engine, doubtful but possible.
I think the calculators work well because they take the Speed and work backwards giving a person the required HP to run run a particular speed.
Hope I’m at least clear as mud
Dan
 
Take the motor to another dyno and it also says 500 hp. Now what do you think?

Here’s the problem and you and I both know it.

I watched part of joes video and turned it off.

You have to test the engine just like they are in the car. You can’t use dyno headers, dyno ignition and dyno water temps and then drop it in the car and blame the dyno for the issue.

I pretty much test at 160 degrees. That’s at least 20 degrees colder than what most guys run. That hurts power. I have tested at 180 if the guy asks for it.

Dyno headers are about always 10-20 better than most headers. Maybe more.

And of course it’s never the chassis that’s an issue. Never.

The car has old tires that are hard as wood. The converter is wrong (that’s a HUGE issue), gearing is off, junk shocks (I’m still appalled going to the track today and seeing cars with absolutely junk shocks on them), the chassis is bound up because it’s bent and hadn’t been serviced since water got wet.

The ignition in the car is different so that means the timing most likely isn’t correct like it may have been on the dyno.

I could go on and on but I’ll lay out the real truth (which I know you know 92b but it needs to be repeated over and over and over until it sinks in) and that is the correction factor.

I don’t care which CF is used it will only be correct IF the exact conditions of the correction factor is met.

Since I use (and will continue to do so) J607 which is also called “Standard Temperature and Pressure and that’s 60 degrees F, a 29.92 barometer and 0 humidity.

So if my CORRECTED numbers say the engine makes 500 hp at STP that means it only makes THAT power at the above conditions. PERIOD. End of the discussion.

You can use a “newer” CF, but the corrected power numbers will only be actual when the conditions of that correction factor are met. EVER.

Where I live, on a “good” weather day my correction factor will be 6%. On some days I’ve seen damn near 13% correction!

That means on that day the engine is making that percentage LESS on the dyno (observed power) and no more.

Here’s another catch. Even the OBSERVED (uncorrected numbers) are only valid when the weather conditions are the same as they are on the exact day the engine was on the pump.

As dyno operators we need to do better at explaining this stuff to the end users. No matter what correction factor is used it’s only correct for that day and those conditions.

No matter what the observed numbers are, they are only correct for those conditions.

The correction factor (whatever CF is used) is only used so I can test an engine in August of 2023 and again in January 2026 and be able to take weather out of the equation so I can compare numbers.

If we didn’t use a CF then the same engine tested in August would make less power (typically) than it would in January.

So how would I know if any updates and upgrades I did to the engine made more (or less) power if I’m chasing weather?

It’s impossible.

I guarantee everyone that the dyno numbers were not wrong. The end user doesn’t understand how it works.

Joe didn’t get burned by dyno testing. He doesn’t know what he doesn’t know.

Oh, here’s another one of my favorite power loser issues.

The fuel system on my dyno is capable of well over 1200 hp. Easily.

When the customer puts the engine in the car and the fuel system is questionable at best and I’ve seen some real garbage fuel systems out there and the car is slow it’s never the fuel system either.

I forgot about water pumps. I see way too many guys testing with electric water pumps on the dyno and they use a mechanical pump in the car.

I’m going to test my engine with an electric pump, a mechanical pump at 6% over driven and the same pump at 20% over driven so I can see the power losses.

Again, that testing is only valid on my engine with my pumps and pulleys. But the numbers will be valid.

So if we just look at the losses from dyno headers to chassis headers (let’s just say it’s 12 hp), cold coolant (10 hp), weak fuel system (10 hp), weak ignition or an ignition with a different retard rate (15 hp) and an electric water pump (10 hp) that’s 57 (FIFTY SEVEN) hp difference right there.

And I believe those to be minimum losses. I know I’ve seen more losses than that.

I blame us, the dyno operators for not doing a better job of educating the end user about how this tool works, its limitations and its benefits and I hold the end user equally responsible for not testing as close as can be done on the dyno like it is in the car and for neglecting chassis and chassis tuning and blaming the tool (dyno) rather than taking a long look in the mirror for some of the problems.

That’s just my .03 cents from dyno testing stuff for close to 30 years now.
 
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You didn't answer. Which one is closest by common sense. I gave the facts of the truck you need. Does it take 500 hp to run 87 with that combo of weight/stall/gear/slicks ??
My point is you are making the assumption that the motor didn't really make 500 hp at the dyno based on the mph at the track.without first verifying that the motor is or is not still making 500 hp.

If a top notch race team uploads at the track with there fresh off the dyno engine and it runs 100 hp slow on the mph are they going to say "Oh well our dyno must be wrong."

More likely they are going to check all the variables that could have changed since the motor came off the dyno to make sure that isn't the problem. Timing, fuelsystem, electrical compression, chassis etc. And if they don't find a problem anywhere first thing they are going to do when they get back to the shop is put the motor back on the dyno and make sure it is still making the hp it was. If it is then they might take the motor to another shop and verify their own dyno isn'tthe problem. If you don't systematically following a procedure to verify where you are at you are left just guessing.
 
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