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FE Power Forums => Non-FE Discussion Forum => Topic started by: Stangman on July 15, 2022, 10:51:54 PM

Title: Drivetrain loss
Post by: Stangman on July 15, 2022, 10:51:54 PM
I know obviously every car is different but let’s say my car, obviously a 9 inch and a c-6 with 3000 stall what do you think the horsepower loss is. I know a c-4 doesn’t draw as much horsepower Jay said it was a big difference. If I do the Wallace calculator it says I have about 490-507 horsepower at the rear wheels depending on the weight I put in. Was wondering what the loss is to know approximately what it was making at the crank.
Title: Re: Drivetrain loss
Post by: jayb on July 16, 2022, 09:19:49 AM
The number I've heard for a stock C6 is 55 HP.  C4 is supposed to eat about 20-25.  Manual transmissions eat even less.  Not sure about the 9", maybe 5%-6% as a guess?
Title: Re: Drivetrain loss
Post by: machoneman on July 17, 2022, 07:26:52 PM
Old post but the Glide is best, c-6 the worst.

https://www.460ford.com/threads/transmission-specifications-including-parasitic-hp-losses.118570/
Title: Re: Drivetrain loss
Post by: Tommy-T on July 19, 2022, 12:23:31 PM
The poor 'ol C6.

Changing to a C4 behind your hot FE will easily net you 2-3 tenths. Proven time and again.

Thing is, you'll need the entire "guts" of the C4 to be aftermarket to hold up to 500 foot pounds of torque. Even then, 2 maybe 3 years of beating on it will do it in. It's tiny. Plenty of places willing to sell you a C4 for 3-5K. Many guys bring an "extra" to the track "just in case".

A competent stock rebuild of a C6 with a shift kit will easily handle that. Put it in your 11 second car and forget about it until you need to freshen up your motor. It'll probably still be ok. You can "rollerize" your C6 and maybe get a tenth back.

You can have your 3 tenths and I'll keep my anvil C6.
Title: Re: Drivetrain loss
Post by: Stangman on July 19, 2022, 12:56:50 PM
thanks guys. Ya know Im not sure if Im trying to talk myself into a c-4 or not but my c-6 has been fine.
About 5 years ago would have been the time to go c-4 when I did my c-6 in.  I bought a new one from TCI
and at the time I didnt have the extra 2500 to go c-4. Im supposed to have my motor dynoed on Friday so Ive been
trying to figure out my old HP to my new HP and figure out about what I will be running. I guess its just alittle bench racing
cause Im bored as hell not having my car. Machoneman thats some list I didnt realize the powerglide was so efficient.
Not that Im gonna get one but do they make adapters for the FE. Well hopefully the motor will be good and I can get back out there.
Title: Re: Drivetrain loss
Post by: Falcon67 on July 20, 2022, 12:01:16 PM
The difference is internal rotating mass and the C6 has a lot.  Big heavy drums take power to accelerate.  Little C4 stuff spins up fast, spins up easier when rollerized.  If you set up the roller drivetrain in a C4, update the drums to 5~6 plates with bleed holes, update the oiling paths and use a 6 pinion planetary, updated input shaft and welded front drum you can really beat hell out of one.  At something like 500 lt/lbs for sure you'd probably want to look inside after every season or so, depending on how many runs.  I have a rollerized C4 that's been behind 300, 500 and currently about 460 HP motors and I haven't looked at the guts in maybe 8 years.  Clicks off gears like a clock.

If you reduce the C6 internal rotating weight in some way, then you get power back.  Just like in the driveline - a reduction in rotating mass is stated to be about 5 times more effective in freeing power than removing static weight.  Hence the carbon fiber driveshafts, lightened gears, drilled axles, super light rims, etc.
Title: Re: Drivetrain loss
Post by: Gaugster on July 20, 2022, 12:16:35 PM
I have referenced the list that Machoneman posted. This jived with other figures I found in my research.

I'll have to look and see what I found for my 6R80. Obviously a different animal all together but they handle 650HP/TQ bone stock. A great platform to work with but a huge undertaking to convert.
Title: Re: Drivetrain loss
Post by: machoneman on July 20, 2022, 12:20:43 PM
Going fast (or quick) costs a lot. How fast do you want to go? LOL

Had to mention this. In a hat tip to racers looking for every single and often very slight advantage, some years ago a NHRA SS class 426 Hemi Cuda showed up at a national event with a Chevy 12-bolt gears grafted into a Ford 9" rear. Since the hypoid angle is less than Ford gears, it was found that the hp required to turn those gears was measurably less, albeit not by much! All Hemi Cudas and Darts soon switched out their Dana 60's or true Ford 9" rears to the Chevy gears.

Like I said, how far one wants to go costs $$$.   
Title: Re: Drivetrain loss
Post by: machoneman on July 20, 2022, 12:26:20 PM
Machoneman that's some list I didn't realize the powerglide was so efficient.

Someone on the old 'Net 54 Forum posted long ago pics of a Glide's disassembled internals next to either a C-4 or C-6 (think it was a 6). Anyway, the size and number or internals is dramatically different as is the weight of rotating parts. Yes, it's a 2 speed versus a 3 speed but virtually all racers who by rules run an auto or have a choice....use the Glide and for good reason. 
Title: Re: Drivetrain loss
Post by: Stangman on July 20, 2022, 12:35:39 PM
Going fast (or quick) costs a lot. How fast do you want to go? LOL

Had to mention this. In a hat tip to racers looking for every single and often very slight advantage, some years ago a NHRA SS class 426 Hemi Cuda showed up at a national event with a Chevy 12-bolt gears grafted into a Ford 9" rear. Since the hypoid angle is less than Ford gears, it was found that the hp required to turn those gears was measurably less, albeit not by much! All Hemi Cudas and Darts soon switched out their Dana 60's or true Ford 9" rears to the Chevy gears.

Like I said, how far one wants to go costs $$$.   

well whatever I run now will be it my car isnt a race car and dont want to switch it over to one. But I was thinking if the motor has to spin a c-6 and it costs 55 horsepower
would the motor be working less if it had to spin something with 30 horsepower. Yes the car will be faster and wouldnt i be working the motor less?
Just things I was thinking about.
Title: Re: Drivetrain loss
Post by: Falcon67 on July 21, 2022, 10:13:45 AM
Technically yes - it take energy to make power to move the vehicle and any reduction in parasitic power loss will make more efficient use of the available energy.   Would you notice the difference in wear & tear on the engine over 10~15 years?  Probably not.  Would the small increase in efficiency be worth the expense of an adapter bell, custom converter, spacers, flex plate, etc, etc?  Not likely.  A C6 is a stout trans and I imagine with modern parts ad maybe a few tweaks would give good extended service.  If you want a couple more MPH and/or a few tenths reduction in ET on a drag strip, then that's whole different set of priorities.
Title: Re: Drivetrain loss
Post by: FrozenMerc on July 21, 2022, 12:59:05 PM
Something else for you to think about.  I spent 13 years in the powersports industry (ATV's and Side x Sides).  Your typical ATV with a Kevlar Belt CVT style transmission, high angle CV joints in the halfshafts, and straight cut bevel gears in the trans and differentials will lose between 35% and 45% of the engines crankshaft power to the drivetrain before it gets to the wheels.  I.E., an 80 Hp 950 cc V-Twin on the engine dyno was putting about 48 hp to the ground on the chassis dyno.  Obviously this is on the extreme end of drivetrain in-efficiency spectrum, but that 32 hp that is lost has to go somewhere.  Generally it manifests itself as heat due to internal friction, and is a big reason why the drivetrain components where not expected to last much over 150 or 200 hrs of operation, equivalent to 5000 thousand miles at most.  Much different than the automotive side of things, but the concepts are the same.  There is a direct relationship with the amount of Energy or Power that is consumed by each drivetrain component and how long it lasts.
Title: Re: Drivetrain loss
Post by: TimeWarpF100 on July 21, 2022, 12:59:34 PM
I know obviously every car is different but let’s say my car, obviously a 9 inch and a c-6 with 3000 stall what do you think the horsepower loss is. I know a c-4 doesn’t draw as much horsepower Jay said it was a big difference. If I do the Wallace calculator it says I have about 490-507 horsepower at the rear wheels depending on the weight I put in. Was wondering what the loss is to know approximately what it was making at the crank.

Approx 25 yrs ago I did a good 1/2 dozen from engine dyno to chassis dyno combo's.  FE C6 and FE Toploader. 1 429 SCJ
In the 400-500 hp area it was almost exactly a 100 hp loss with 4 spd and a 125 hp loss with c6.   Those losses did include exhaust. Good exhaust but maybe not ideal but as un-restrictive as I could make them at the time.
Title: Re: Drivetrain loss
Post by: winr1 on July 21, 2022, 10:39:15 PM
Would the percentage lost be the same on a lower horse power or higher horse power mill ??


Ricky.
Title: Re: Drivetrain loss
Post by: Stangman on July 21, 2022, 11:06:13 PM
A 100-125 horse is a lot of power to leave out there TimeWarp. Ya know my car doesn’t weight a lot either but it sure is hard to push. I always think if I can get it to roll easier that would pick it up also.
Title: Re: Drivetrain loss
Post by: mike7570 on July 21, 2022, 11:25:29 PM
A 100-125 horse is a lot of power to leave out there TimeWarp. Ya know my car doesn’t weight a lot either but it sure is hard to push. I always think if I can get it to roll easier that would pick it up also.
A good stocker or class car will roll extremely easy. There is a lot of places to reduce rolling resistance from the brakes to alignment, light weight wheels and tires, gears and bearings. The stocker I’m currently building will roll easily with just one hand. (Maybe it’s because I don’t have the engine in it yet!  ;D. )
I’ve spent time and money making sure it rolls with as little resistance as possible.
Title: Re: Drivetrain loss
Post by: cjshaker on July 22, 2022, 01:13:40 AM
A 100-125 horse is a lot of power to leave out there TimeWarp. Ya know my car doesn’t weight a lot either but it sure is hard to push. I always think if I can get it to roll easier that would pick it up also.


That would be for the entire drivetrain. The rear end and wheel/tire combo will be eating most of that. Not to mention that full exhaust, no matter how efficient it was. You'll start going down an expensive rabbit hole when you start chasing driveline losses, like Chris alluded to. Then again, who wants to be buried with their money?  ;D

The resistance to rolling is another matter. If a car doesn't roll easily, that translates to resistance in acceleration. Not always an easy matter to deal with. Brake drag, even if just a little, affects that pretty significantly. Residual valves on the front system and light contact of drum brakes surely wouldn't help on the strip, but they do make for a safer street car. And of course 14 lbs of pressure in big fat tires doesn't help in pushing anything.
Title: Re: Drivetrain loss
Post by: machoneman on July 22, 2022, 09:27:15 AM
The stocker I’m currently building will roll easily with just one hand. (Maybe it’s because I don’t have the engine in it yet!  ;D. )
I’ve spent time and money making sure it rolls with as little resistance as possible.
[/quote]

Engine less cars are always easy to push! Engine, trans, crossmember, driveshaft? Easy 750-800 lbs. Try it again one it's together and you'll see. As side note, we ran a spool in our drag car and trying to push it in a turn, forward or back, was a pain indeed. Often had to jack up the rear to make the turn into our garage. .   
Title: Re: Drivetrain loss
Post by: cjshaker on July 22, 2022, 10:51:38 AM
The stocker I’m currently building will roll easily with just one hand. (Maybe it’s because I don’t have the engine in it yet!  ;D. )
I’ve spent time and money making sure it rolls with as little resistance as possible.

Engine less cars are always easy to push! Engine, trans, crossmember, driveshaft? Easy 750-800 lbs. Try it again one it's together and you'll see. As side note, we ran a spool in our drag car and trying to push it in a turn, forward or back, was a pain indeed. Often had to jack up the rear to make the turn into our garage. .
[/quote]

I'm pretty sure Mike has experience with fully built cars, he's been racing for a long time. And he is correct that they should push easily when prepped for drag strip duty. Of course pushing a spool through a turn won't be easy, and like I said, a big fat squishy tire won't help, but a properly set up drag car should not push hard.
Title: Re: Drivetrain loss
Post by: Rory428 on July 22, 2022, 03:51:17 PM
Not sure how much of it was from internal friction and rotating weight, but when I had a C6 in my Fairmont, it was a fairly good piece, had all the low drag Torrington bearing thrust washers, but still had a stock steel drum. When I swapped out the C6, to a Jerico 4 speed, with no other changes to the car, the 1/4 mile numbers improved by over 5 tenths, and 6 MPH. And that was with a 8" torque convertor, and a Art Carr transbrake/reverse pattern valve body, launching at WOT at 5200 RPM. Many of the Stock and Super Stock Ford racers are using big $$$ custom built C4s behind their FEs and 429/460 engines, but some are running equally expensive C6s, that have had all the heavy internals, replaced with much lighter, MoPar 904 guts. Ritchey Pauley told me that his Pro Trans C6 was about as good as his C4 in back to back testing. As for Powerglides, several years ago, NHRA started to allow cars that were only available with 2 speed automatics, use a 3 speed. So, now , most former Powerglide Stock and S/S Chevys are running either a trick lightweight Turbo 350, or Turbo 200, instead of a trick Powerglide. The racers that I know that has switched from a 2 speed to a 3 speed, say that the lower first gear ratio, gets the car off the line much harder, and the closer ratio drops, help keep the engine in the power band.
Title: Re: Drivetrain loss
Post by: Gregwill16 on July 22, 2022, 04:40:31 PM
I did realize the C6 was a big power hog. But what doesn't completely make since to me is the muscle car era time slips. For instance, the Ford numbers showed the 68 CJ automatic cars as fast or faster than the 4 speed cars. I assume this had a lot to do with traction technology, but you would think that loss would be hard to overcome.
Title: Re: Drivetrain loss
Post by: mike7570 on July 22, 2022, 07:54:59 PM
I'm pretty sure Mike has experience with fully built cars, he's been racing for a long time. And he is correct that they should push easily when prepped for drag strip duty. Of course pushing a spool through a turn won't be easy, and like I said, a big fat squishy tire won't help, but a properly set up drag car should not push hard.
Big squishy tires? I’ve heard of big soft tires but I don’t think anyone has called them squishy. Lol
My super-gas car had 14.5x32’s and only ran 6.5lbs of air. I guess they fit the definition of squishy.
You had to plan your turns when coasting in the pits or return road, as soon as you moved the steering wheel it was like putting on the brakes. Those squishy tires would cause a lot of resistance if the rear axel isn’t mounted real straight.
Title: Re: Drivetrain loss
Post by: Stangman on July 22, 2022, 08:08:00 PM
Mike7570 what are some of the things you do to stockers or any of your cars to get them to roll better. My motor is out and it rolls alot easier but ive seen some guys at the track and they just lean on there cars and they roll. Shit i have to really dig in to get it to roll.
Title: Re: Drivetrain loss
Post by: mike7570 on July 23, 2022, 11:44:11 AM
Since I was building a new car from scratch it was a bit easier to justify expenditures since it was already apart and needed new everything in the drive train and suspension.
My tires and rims are about as light a set as I could find (front tire/rim weighs just 17lbs ea., rear slicks/rims weigh 38lbs ea.) The 3rd member was set up professionally (I didn't do it  ;D) for racing and I had purchased light weight MW and Strange components including REM finished gears and ball bearing pinion support. The axle tubes received new big ends and were verified straight. There are all new wheel bearings (couldn't afford the ceramic coated versions) and new Wilwood 4 wheel disc brakes that don't drag (I'll be keeping an eye on that). The final alignment will be carefully done after all of the weight is back in the car including driver at the anticipated ride height while running down the track (not at parked ride height)
Oh, I forgot to mention very light weight synthetic gear oil. (Probably wouldn't run it in a street car)
The alignment front and back along with brake drag and weight are probably the key items. If you jack the front end up and give the wheels a spin by hand how long will they keep rotating?
Title: Re: Drivetrain loss
Post by: Rory428 on July 23, 2022, 11:49:52 AM
I did realize the C6 was a big power hog. But what doesn't completely make since to me is the muscle car era time slips. For instance, the Ford numbers showed the 68 CJ automatic cars as fast or faster than the 4 speed cars. I assume this had a lot to do with traction technology, but you would think that loss would be hard to overcome.

Keep in mind that the Cobra Jet Mustangs were fitting with F70-14 bias belted tires when new, which is smaller than my wifes 4 cylinder Toyota Corolla! Pretty touchy getting a 428 4 speed car off the line with such skinny tires, especially when so many Ford performance cars of the era didn`t have Traction Lok limited slip as standard equipment. And the horrible factory 4 speed shifters sure didn`t help either.
Title: Re: Drivetrain loss
Post by: cammerfe on July 23, 2022, 10:29:25 PM
I changed the knob on my factory shifter as soon as I got home from the dealer after picking it up. I had to wait until friday to get a Hurst as a replacement. ;)

KS
Title: Re: Drivetrain loss
Post by: Gregwill16 on July 24, 2022, 08:48:13 AM
I went back and reread some of the Ford internal documents Dennis posted on the CJ site and the numbers do support the C6 drivetrain losses. In SS/G class the 68 CJ stick cars (with relocated battery) were 3 tenths quicker (11.4 vs 11.7) than the automatic cars. But tests for competition in all the other classes, the stick cars were only a tenth quicker. So appears they had to figure out how to get the "extra" power to the ground in the stick cars.
Title: Re: Drivetrain loss
Post by: machoneman on July 24, 2022, 01:04:13 PM
Off the topic but....I've always wondered what a Lenco (4-speeds, as the Pro Stocker used to use) ate up in hp compared to a 4-speed tranny. Have never seen any comparisons.

Bro' James was always able to get the crews of visiting Pro Stock cars (1972-1974 or so) to talk to him in the pits at Union Grove WI's Dragaway. Once before the finals, Glidden vs. Nicholson IIRC, one crew man (Maybe Glidden's son?) was under the car, draining all the rear end gear fluid. Then, he proceeded to drain about a pint or so from the Lenco! Said they needed that edge to reduce drag while running near identical e.t.'s. Glidden won.

This move made sense to me as just how many revolutions would a ring & pinion make in a 1/4 mile. Not many although I would not recommend this seemingly drastic move!
Title: Re: Drivetrain loss
Post by: Rory428 on July 24, 2022, 08:40:47 PM
Off the topic but....I've always wondered what a Lenco (4-speeds, as the Pro Stocker used to use) ate up in hp compared to a 4-speed tranny. Have never seen any comparisons.

Bro' James was always able to get the crews of visiting Pro Stock cars (1972-1974 or so) to talk to him in the pits at Union Grove WI's Dragaway. Once before the finals, Glidden vs. Nicholson IIRC, one crew man (Maybe Glidden's son?) was under the car, draining all the rear end gear fluid. Then, he proceeded to drain about a pint or so from the Lenco! Said they needed that edge to reduce drag while running near identical e.t.'s. Glidden won.

This move made sense to me as just how many revolutions would a ring & pinion make in a 1/4 mile. Not many although I would not recommend this seemingly drastic move!
I have a racing buddy, back in British Columbia, who races a high 8 second 67 Fairlane, and has raced it over the years with a Toploader, a Jerico 4 speed, a 5 speed Lenco, and a Liberty clutchless 5 speed. He told me that the Liberty was about 1 1/2 tenths of a second quicker in the 1/4 mile, than his Lenco. I don`t think there has been a competitive NHRA Pro Stock car using a Lenco in well over 20 years.
Title: Re: Drivetrain loss
Post by: cammerfe on July 24, 2022, 10:11:19 PM
FWIW, back in the late '60s, Doug Nash built a Funny Car based on a Bronco. The chassis was all aluminum and he was running a small block Ford on a good dose of pop. He was likely making somewhere beyond 1500 Horsepower. I was working with John Corrunker at CorBan at the time and we were tasked with building the C4 transes that Doug was running. As I remember, the trans needed to be completely re-done after no more than a couple of passes. Every week we'd build three transmissions in order for him to be equipped through an entire weekend of competition.

Sometimes he'd try to get a third run before swapping, but it was always a bit iffy on that third go. Two passes were quite safe.

He WAS using 80 % nitro or more most of the time.

KS
Title: Re: Drivetrain loss
Post by: machoneman on July 25, 2022, 04:32:20 PM
Off the topic but....I've always wondered what a Lenco (4-speeds, as the Pro Stocker used to use) ate up in hp compared to a 4-speed tranny. Have never seen any comparisons.

Bro' James was always able to get the crews of visiting Pro Stock cars (1972-1974 or so) to talk to him in the pits at Union Grove WI's Dragaway. Once before the finals, Glidden vs. Nicholson IIRC, one crew man (Maybe Glidden's son?) was under the car, draining all the rear end gear fluid. Then, he proceeded to drain about a pint or so from the Lenco! Said they needed that edge to reduce drag while running near identical e.t.'s. Glidden won.

This move made sense to me as just how many revolutions would a ring & pinion make in a 1/4 mile. Not many although I would not recommend this seemingly drastic move!
I have a racing buddy, back in British Columbia, who races a high 8 second 67 Fairlane, and has raced it over the years with a Toploader, a Jerico 4 speed, a 5 speed Lenco, and a Liberty clutchless 5 speed. He told me that the Liberty was about 1 1/2 tenths of a second quicker in the 1/4 mile, than his Lenco. I don`t think there has been a competitive NHRA Pro Stock car using a Lenco in well over 20 years.

Hey thanks Rory! Had never seen a comparison before. And yes, the Lenco is certainly old school now but many a racer turned into Ronnie Sox on the easy shifting compared to 4-speeds of the era. And none of those OEM based 4-speeds lived long behind ever more powerful Pro Stok engines. The new breed of modern, all-new design stick trans, once they became available, buried the Lenco-type transmissions in door slammers at least.
Title: Re: Drivetrain loss
Post by: machoneman on July 25, 2022, 04:43:11 PM
FWIW, back in the late '60s, Doug Nash built a Funny Car based on a Bronco. The chassis was all aluminum and he was running a small block Ford on a good dose of pop. He was likely making somewhere beyond 1500 Horsepower. I was working with John Corrunker at CorBan at the time and we were tasked with building the C4 transes that Doug was running. As I remember, the trans needed to be completely re-done after no more than a couple of passes. Every week we'd build three transmissions in order for him to be equipped through an entire weekend of competition.

Sometimes he'd try to get a third run before swapping, but it was always a bit iffy on that third go. Two passes were quite safe.

He WAS using 80 % nitro or more most of the time.

KS

The Bronco Buster! Loved the rules bending before, like many Fords, it got "busted" by the NHRA and banned. Very innovative, knew it was super light and burned up many transmissions but we thought not as many as you've stated. Still wonder how a 1,500 hp mainly OEM SBF (block and heads for sure) lived longer than the transmissions! My Nash based Richmond 5-speed is still going strong 28 years later. Thanks Doug wherever you are.

https://i.pinimg.com/originals/37/b0/45/37b0457aa0f56dd896704332373eec56.jpg