Chassis Dyno results are in 440-6 mild cam

Author Topic: Chassis Dyno results are in 440-6 mild cam  (Read 8938 times)

Offline 351c4v71

  • Jr. Member
  • **
  • Posts: 244
Chassis Dyno results are in 440-6 mild cam
« on: August 02, 2012 - 12:41:34 PM »
Hi guys,
Well I finally got my chassis dyno results. Speed shop say they use strictest evaluation, something about SAE.
71 cuda clone, 440-6, headers, 4-speed, electronic distributor, no head porting (stock heads).
322hp at wheels (+15%) = 380hp at engine.
419 ft-lbs at wheels (+15%) = 500ft-lbs at engine.
Cam is very mild, comp cam 270H
Dur: 270-270   @0.050 lift : 224-224
Valve lift : 0.47 – 0.47
Lobe lift : 0.313 – 0.313
Will post graphic later, maybe.




Offline footin70rt

  • Jr. Member
  • **
  • Posts: 286
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #1 on: August 02, 2012 - 04:05:33 PM »
Should have some pretty good grunt! Torque numbers look good, what rpm was max torque?
Thomas
Driving the same 70 R/T since October 1985
Native of Bozeman, MT

Offline js23nob

  • Jr. Member
  • **
  • Posts: 169
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #2 on: August 25, 2012 - 07:30:37 AM »
with 322 hp at the rears, its more like 412 hp at the flywheel,

rear wheel horse power is basically what your engine makes in kilo watt,

322 x 1.28 = 412.16hp,( miss calculated oops)

i engine dynoed a 360 sb and it made 426 hp at the flywheel,

then we put it in the car and it made 317 at the rear wheels on a chassis dyno,

« Last Edit: August 26, 2012 - 08:17:30 AM by js23nob »
Mopar or no car

Offline brads70

  • C-C.com Expert
  • ********
  • Posts: 18747
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #3 on: August 25, 2012 - 07:57:14 AM »
 :clapping: Nice!
Now go order some new rear tires!  :aarg:   :smilielol:
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0

Offline johannes

  • Jr. Member
  • **
  • Posts: 281
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #4 on: August 25, 2012 - 08:17:14 PM »
with 322 hp at the rears, its more like 431 hp at the flywheel,

rear wheel horse power is basically what your engine makes in kilo watt,

322 x 1.34 = 431.48hp,

i engine dynoed a 360 sb and it made 426 hp at the flywheel,

then we put it in the car and it made 317 at the rear wheels on a chassis dyno,

Please stop spreading BS.
Losses from engine dyno to RW HP  car is NOT a fixed percentage.
Example;
An automatic tranny have greater losses than a stick shift.
Larger rear axels have greater losses....
A belt driven fan, looses more HP the higher the RPM.... hence a screamer will loose more HP than a torque-elephant.
Using an electric fan losses are less, and an engine having serpentine belt gains maybe 4-7 HP over a V-belt.
Tire pressure will effect a reading on a roller-dyno....anyone who has tried to push a car having under inflated tires understands this.


Now, was you engine dynoed with belts at all ???? before comparing to RW HP?
What exhaust system was used?
What type of dyno?
Etc, etc...

ESTIMATES range between 10 and 20%, but the smaller the engine, the greater a fan loss of say 30HP will become....in %

Any engine without boost, closing in on 1 RW HP/CID is a VERY strong engine, which translates to say HEMI, wild cam and high RPM, poor idling, and lousy gas milage.
.... and in many cases a non robust engine,... as material fatigue will come into play due to high RPM. ( A dyno mule only )

351c4v71 enjoy your mild 440...
It is hopefully a robust engine that will serve you for many years to come.
Thanks for sharing your specs. 
May I ask; What gas milage do you get, and which axle ratio and tire size?


Offline bad440

  • Jr. Member
  • **
  • Posts: 66
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #5 on: August 25, 2012 - 11:13:41 PM »
The new 392 makes an average of 420HP at wheels and produces a factory rating of 470 at crank. The 5.7 in the R/T makes an average of 335 at the wheels(stock) and produces aprox. 390 at the crank, not sure where 431 HP comes from when rear wheel power is only 322. Lots of torque though.
Sudbury, Ontario, Canada

Offline js23nob

  • Jr. Member
  • **
  • Posts: 169
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #6 on: August 26, 2012 - 08:13:10 AM »
 we dynoed a stock srt8 300c 6.1L and it gets 325 hp at the wheels,
they are rated at 425hp at the engine!!
I think in the USA your dynos show more horse power than in Aus,
 our correction factor is really hard to make horse power,
now my valiant  charger was a manual with 30 pounds in the tyres,
diff gears dont change the numbers on my car, it had 3.45 gears
then it had 4.1 gears and the numbers were about the same,
just peaked at a different road speed, engine dynoed with alternator
fan pulleys air cleaner, full exhaust with mufflers,
with all my friends cars and people that have had engines dynoed then rear wheel dynoed,
its all about the same conversion numbers, you lose a little more with autos,
because of converter slip, about 4 to 5 percent slip,
look up on you tube ( dominator engines hurstune 363.3 hp) this is my friends car, he is building my 440
That car has gone a best of 11.6 @116 mph manual at 3100 pounds,
that engine made 465 at the crank with all accesories,
when checked against the moroso calculator it is nearly spot on,
also look up faraone engines 265 hemi 400 fly wheel hp,
also look up vc valiant v8 turbo dyno cotm 2012, on 4 pounds of boost this car makes
460 hp @ the wheels first time at the drags 3700 pounds race weight one pass it went 11.3 @ 124 mph,
this is my mates car that we built in the last 4 years, on 12 pounds of boost it has made 588 hp @ the wheels,
so i have seen alot of cars on the dyno here in Aus, engine and @ the wheels
« Last Edit: August 26, 2012 - 08:44:45 AM by js23nob »
Mopar or no car

Offline johannes

  • Jr. Member
  • **
  • Posts: 281
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #7 on: August 26, 2012 - 02:24:13 PM »
I think in the USA your dynos show more horse power than in Aus,
 
.....I think we're on the same page...

I believe many "experts" exaggerate the engine HP.... and starts throwing around fiddle factors when their bluff is called on a dyno.  :screwy:
.... and to make things worse, they start putting these fiddle factors into the software of their own dynos, so they can remain the "best" enginebuilders around.

   :banghead: ...I mistook you for one of those... SORRY !!   :banghead:

NOBODY CARES WHAT GROSS HP AN ENGINE MAKES !   Agree??

Now with REALISTIC HPmeasured on engine crank, using same exhaust system as in the car, etc,etc..... the losses is expected to lie in the 10-20% range.
.... your typo error correction factor of 34% just had to be commented.... agree??

Thanks for sharing examples and vids.
Any gas milage numbers you can share??

Ohh... love your fact on the 6.1 L SRT engine... measuring only 325 RM HP...
 :horse: :horse: :horse:

Offline js23nob

  • Jr. Member
  • **
  • Posts: 169
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #8 on: August 27, 2012 - 02:18:17 AM »
on the chassis dyno if you move the heat probe between runs u can make about 20 horse power more,
 the bodgey dyno guys do it hear and say ( look we found 20 horse power more by doing nothing)
Mopar or no car

Offline 351c4v71

  • Jr. Member
  • **
  • Posts: 244
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #9 on: September 03, 2012 - 04:13:59 PM »
Here are the print outs.
This is a very mild cam, regular heads (no porting), long tube headers, electronic ignition (nothing fancy), 4 speed, 440-6, block is dated 74 I think , has been rebored with 6 pack pistons (as per previous owner).


Offline Chryco Psycho

  • Administrator
  • C-C.com Guru
  • *****
  • Posts: 36620
  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #10 on: September 03, 2012 - 08:49:55 PM »
nice flat torque curve  :2thumbs:

Challenger - You`ll wish You Hadn`t

Offline Oldschool

  • Administrator
  • Permanent Resident
  • *****
  • Posts: 13195
  • Member Since 9-05-06
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #11 on: September 04, 2012 - 04:05:55 PM »
The crank/rear wheel HP ratings differences is an excellent point. We all agree that there is HP loss throughout the drivetrain. How much is always a question for debate.

This brings me to ask this question: When HP is figured by using quarter mile times/mph, is the HP that is arrived at by these formulas at the crank or at the rear wheels?

I think it is at the rear wheels. Seems to me that the track doesn't know how much engine HP you are running, only how much you were able to put down on the track.

Discuss.......
Ken  --  In Georgia

MOPAR-------"Built To Run------Here To Stay"

Offline Chryco Psycho

  • Administrator
  • C-C.com Guru
  • *****
  • Posts: 36620
  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Chassis Dyno results are in 440-6 mild cam
« Reply #12 on: September 05, 2012 - 04:49:22 PM »
 :iagree:
 Weight + ET & Speed = RWHP

Challenger - You`ll wish You Hadn`t