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First Time on Dyno!

Started by Evoking, October 12, 2018, 10:07:09 AM

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Evoking

Had my 68 dyno tuned a couple days ago!  385hp and 407 lb-ft which equates to approx 550hp at the crank.  I was hoping for a nice round 600 crank hp but this is not too shabby.


INTMD8

Seems like it had more in it as it had not peaked yet  :2thumbs:

Not sure about 30% drivetrain loss however.
69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 595rwhp 475rwtq

c00nhunterjoe

Not to bust the bubble but 385 at the wheels is not 550 at the crank. Best to hit the 1/4 mile for a mph reading to give you an accurate hp number. I was never a fan of dynos for anything other then tuning or inflating chests.

alfaitalia

These numbers are from an article in Car Craft Magazine.

Powerglide_____18 hp
TH-350________36 hp
TH-400________44 hp
Ford_C-6______55-60 hp
Ford_C-4______28 hp
Ford_FMX______25 hp
Chrysler_A904__25 hp
Chrysler_727___45 hp

This is how much power it took to drive a on a tranny dyno...727 was second worst!  It's not a linear thing though so the more power you put through it the more power that will be lost. The figures quoted are to spin just the tranny.....so you would need a formula to work out how much your particular engine will sacrifice to the drive line. Add that to about 6 to 8% lost at the rear diff and it soon adds up.
If at first you don't succeed, skydiving is not for you !!

cdr

on a Dyno jet is is about a 13% loss, so 445 hp @ crank
LINK TO MY STORY http://www.onallcylinders.com/2015/11/16/ride-shares-charlie-keel-battles-cancer-ms-to-build-brilliant-1968-dodge-charger/  
                                                                                           
68 Charger 512 cid,9.7to1,Hilborn EFI,Home ported 440 source heads,small hyd roller cam,COLD A/C ,,a518 trans,Dana 60 ,4.10 gear,10.93 et,4100lbs on street tires full exhaust daily driver
Charger55 by Charlie Keel, on Flickr

INTMD8

As alfaitalia mentioned, it's not a fixed percentage.

It's more like a fixed amount plus a percentage which varies by car/driveline.

69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 595rwhp 475rwtq

Mike DC

 
727s cost a lot of HP and they also don't break.  It's not a coincidence. 


cdr

Quote from: INTMD8 on October 12, 2018, 12:14:28 PM
As alfaitalia mentioned, it's not a fixed percentage.

It's more like a fixed amount plus a percentage which varies by car/driveline.



it's all a guess , take it to the track as Joe said.
LINK TO MY STORY http://www.onallcylinders.com/2015/11/16/ride-shares-charlie-keel-battles-cancer-ms-to-build-brilliant-1968-dodge-charger/  
                                                                                           
68 Charger 512 cid,9.7to1,Hilborn EFI,Home ported 440 source heads,small hyd roller cam,COLD A/C ,,a518 trans,Dana 60 ,4.10 gear,10.93 et,4100lbs on street tires full exhaust daily driver
Charger55 by Charlie Keel, on Flickr

c00nhunterjoe

And dont forget to get the weather data for your runs when you do go. D/a, humidity, vapor pressure and temp will be most important.

cdr

Quote from: c00nhunterjoe on October 12, 2018, 02:12:53 PM
And dont forget to get the weather data for your runs when you do go. D/a, humidity, vapor pressure and temp will be most important.
And to ad to that,, race weight , that is with driver.
LINK TO MY STORY http://www.onallcylinders.com/2015/11/16/ride-shares-charlie-keel-battles-cancer-ms-to-build-brilliant-1968-dodge-charger/  
                                                                                           
68 Charger 512 cid,9.7to1,Hilborn EFI,Home ported 440 source heads,small hyd roller cam,COLD A/C ,,a518 trans,Dana 60 ,4.10 gear,10.93 et,4100lbs on street tires full exhaust daily driver
Charger55 by Charlie Keel, on Flickr

INTMD8

Wouldn't say it's all a guess.  You can gain a lot of useful information tuning on the dyno but absolutely bring it to the track :)

To add to the density altitude note, dragtimes.com is an easy way to check.
69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 595rwhp 475rwtq

alfaitalia

Even those useful posts and good advice won't tell you the power at the crank...just the tyres. If one car produces 30 brake more than another but loses 30 horse more through the drive line (unlikely I know but just as an example) then, all other factors being equal they will turn in the same times. So the track won't tell you how powerful that car is....just how much it put down. Which arguably is the only figure that counts I guess!....but the op wants to know the power at the crank...track won't help much with that.
If at first you don't succeed, skydiving is not for you !!

Evoking

Quote from: alfaitalia on October 12, 2018, 05:18:13 PM
Even those useful posts and good advice won't tell you the power at the crank...just the tyres. If one car produces 30 brake more than another but loses 30 horse more through the drive line (unlikely I know but just as an example) then, all other factors being equal they will turn in the same times. So the track won't tell you how powerful that car is....just how much it put down. Which arguably is the only figure that counts I guess!....but the op wants to know the power at the crank...track won't help much with that.

I wasn't particularly looking to know power at crank. I had it tuned to smooth out the drivability. Knowing the output was a bonus. This is a cruise in between my much more focused weapons ;-). That said, the shop that did it is Superior Automotive of Orange County. They've been building and tuning engines for like 50 years - literally.  From the Bullit 68 Charger to Eleanor from Gone in 60, Fast & Furious cars and even Jay's personal collection. They engine dyno there as well!  When I reference 30% loss it's not off the top of my head - it's their real world experience with 727's and similar HP.  Had I got this e fine from them we would all know for sure!  I'm thinking it might not be worth pulling it out to confirm haha!

INTMD8

If it truly is 30%, let me know where they get their torque converters so I can make sure to never buy one  :shruggy:

Still curious why they didn't pull it any higher, (unless it lost valve control?)

But yeah, definitely not worth pulling the engine to find out for sure!

Enjoy it, more than enough power to have fun :)  :2thumbs:
69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 595rwhp 475rwtq

Todd Wilson

Quote from: Mike DC (formerly miked) on October 12, 2018, 12:23:20 PM
 
727s cost a lot of HP and they also don't break.  It's not a coincidence. 




Is that why the SS Hemi guys use the 904 adaptor and run 904's??

Todd

Evoking

Quote from: INTMD8 on October 12, 2018, 09:23:19 PM
If it truly is 30%, let me know where they get their torque converters so I can make sure to never buy one  :shruggy:

Still curious why they didn't pull it any higher, (unless it lost valve control?)

But yeah, definitely not worth pulling the engine to find out for sure!

Enjoy it, more than enough power to have fun :)  :2thumbs:

Are you suggesting they should have gone higher than 5500 rpm?  At what RPM range do you guys think peak hp arrives on a stroked 440?

hemi-hampton

Look's like Horsepower was still Climbing at 5,500 rpm's & not dropped off yet while Torque dropped off at around 4,000 rpm's. I'd bee be curious to know where the Horsepower peaks & drops off. LEON.

INTMD8

Quote from: Evoking on October 13, 2018, 10:07:05 AM
Are you suggesting they should have gone higher than 5500 rpm?  At what RPM range do you guys think peak hp arrives on a stroked 440?

Peak hp would arrive at a different rpm for every engine depending on the combination. (being a stroked 440 one of many variables).

But yes, it looks like the run was chopped before it reached peak hp.  Just make sure your driveshaft is within range of critical speed if you turn it higher next time.
69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 595rwhp 475rwtq

c00nhunterjoe

385 to the wheels factoring 30% loss is not 550... check your math.

Ss guys run 904 guts in a 727 case... but yes, for the rotational hp loss. Thus one of the many reasons a 590 hp 4000 race weight b body can go 10.15s in the 1/4.

70 sublime

Quote from: c00nhunterjoe on October 13, 2018, 08:40:51 PM
385 to the wheels factoring 30% loss is not 550... check your math.

Ss guys run 904 guts in a 727 case... but yes, for the rotational hp loss. Thus one of the many reasons a 590 hp 4000 race weight b body can go 10.15s in the 1/4.

550 times .7 (100% - 30%) is 385
next project 70 Charger FJ5 green

RECHRGD

How about 385x1.3=500......
13.53 @ 105.32

70 sublime

Quote from: RECHRGD on October 13, 2018, 10:49:51 PM
How about 385x1.3=500......

He lost 30 % of original HP
Not gain 30 % of rear wheel HP
next project 70 Charger FJ5 green

c00nhunterjoe


Challenger340

Wheel Dyno's can be an excellent Tuning tool.
That said,
it would appear from most threads I've seen on this Site, that every time someone/anyone goes to a Chassis/wheel Dyno and posts the results ? The ensuing conversation then gets fixated on trying to then back-calculate Engine Flywheel Horsepower / Trq ?..... from the Chassis/Wheel numbers recorded.

Why is that ?
You will never know actual Engine/Flywheel HP/Trq because you were NOT measuring Engine/Flywheel power ?

If it makes 385 hp at the wheels and it runs great, be happy  :2thumbs:




Only wimps wear Bowties !

c00nhunterjoe

Well said. Thats why i suggested taking it to the track for some mph data. That is where it counts, not strapped to a roller.

JR

Quote from: Challenger340 on October 14, 2018, 09:49:23 AM
Wheel Dyno's can be an excellent Tuning tool.
That said,
it would appear from most threads I've seen on this Site, that every time someone/anyone goes to a Chassis/wheel Dyno and posts the results ? The ensuing conversation then gets fixated on trying to then back-calculate Engine Flywheel Horsepower / Trq ?..... from the Chassis/Wheel numbers recorded.

Why is that ?
You will never know actual Engine/Flywheel HP/Trq because you were NOT measuring Engine/Flywheel power ?

If it makes 385 hp at the wheels and it runs great, be happy  :2thumbs:







I agree. I could really care less what crank HP is.

Unless you're planning to swap the engine into multiple different vehicles, or maybe plan on swapping transmssions or axles, crank HP seems like a totally irrelevant number (to me.)

70 Charger RT top bananna /68 Charger RT triple green

c00nhunterjoe

I like to dyno the engine before install. Its nice to break them in on the dyno, then do a baseline tune prior to install. That way you know its set and ready to go and any potential problems are found are repaired prior to installing in a car.

RECHRGD

Quote from: 70 sublime on October 14, 2018, 05:13:58 AM
Quote from: RECHRGD on October 13, 2018, 10:49:51 PM
How about 385x1.3=500......

He lost 30 % of original HP
Not gain 30 % of rear wheel HP

Actually, that result is probably closer to reality than the others.  You're looking for a unknown crank hp from a known rwhp. 
13.53 @ 105.32

c00nhunterjoe

Still think he is looking more at 475. Time to hit the 1320 and post the slips!

70sixpkrt

When I first built my motor, it did 498 and 535 tq on an engine dyno. A few years later, I put it on a chassis dyno. I did 399hp with 448 tq and it was running rich. The guy who did the dyno said my car would lose approximately 17% thru the drivetrain since it was a 4 speed. I ran down the strip and did 13.01 at 108 mph. 60 foot time and traction sucked. I really don't think you would lose 30%.


440-6pk, 4-speed, Dana 60 with 3:54  
13.01 @107.93 (street tires spinning all the way down)

Kern Dog

My 440/493 with 10.8 compression and a '509 cam made 369 to the wheels with UNported Edelbrock heads, 2" headers and a Demon 850 4 barrel. I was disappointed too with the numbers. We have all grown up with the "gross HP" advertised numbers so these net numbers are a bit of a kick to the dick.


c00nhunterjoe


6pkrtse

First time on a Dynamometer is always fun. Yes, there are a lot of individual engine shops out there that can pad the #'s by playing with the interia factors on the dyno to make the customer happy. We have 42 individual different dyno rooms at work & ours have to be all OEM calibrated to read "true" numbers. So, if a guy makes 600 at our shop, he could possibly make 640 to 680 or more at another shop & not know the difference.

Here is when we did my Hemi.

https://www.facebook.com/193108010854372/videos/652818031550032/?t=0
1963 Belvedere 413 Max Wedge
1970 Charger R/T S.E. 440 sixpack.
1970 Challenger R/T Drag Radial 528 Hemi
1970 Charger 500 S.E. 440 4 BBL
1970 Road Runner 383 4 BBL
1974 Chrysler New Yorker 440 4 BBL
1996 Dodge Ram 2500 V-10 488 cu in.
2004 Dodge Ram 3500 CTD Dually 6x6
2012 Challenger R/T Classic