Author Topic: My first dyno run...I am soooo happy!!!!  (Read 12203 times)

0 Members and 1 Guest are viewing this topic.

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
My first dyno run...I am soooo happy!!!!
« on: January 02, 2012, 12:49:32 AM »
The  preliminary numbers for my VX800 (Suzuki 800 Vtwin motorcycle) are in at 68 hp and 47 ft# torque.  I was wondering if anyone could  maybe help explain to me the drop in torque.  The base line was 51 or 52 ft# and 57HP (different dyno I know but still a drop in torque was not expected....).  My Mechanic did say that it was a very flat torque curve, FWIW.

The jetting had not been touched, it was set up for an SV650 (thats how the carbs come), and the ignition had not been touched.  I am hoping that we may be able to eek out 70hp, which would mean nearly a 20% increase over stock, not bad IF it hits that.  Any educated guesses as to how many % over stock we get by the ignition module alone?

Cheers
Alan
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline hotrod

  • Hero Member
  • *****
  • Posts: 1231
    • Black Horse photo
Re: My first dyno run...I am soooo happy!!!!
« Reply #1 on: January 02, 2012, 02:13:31 AM »
Can't make any educated guesses without the rpm numbers for the hp and torque on both tests.

Barometric pressure differences, and variation in measurement accuracy on dynos could easily explain that difference.
You would also need to know if both dynos were the same type and using the same correction factor. Even if the two dynos were the same type, and used the same correction factors, variations in the absolute air temperature, humidity and absolute barometric pressure, tire pressure/type, and tie down method (assuming it was a chassis type dyno) could all take their piece of the pie.

Larry

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
Re: My first dyno run...I am soooo happy!!!!
« Reply #2 on: January 02, 2012, 02:26:04 AM »
Larry,

I havent seen the new numbers, it was only a call....What I can tell you is that they are both new (within the past 12 months) Dynojet dynos....Who knows what correction factors are "stock" or normally corrected for/calculated.

Hopefully i'll get to see the charts when the shop reopens for the first time in 2012.
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: My first dyno run...I am soooo happy!!!!
« Reply #3 on: January 02, 2012, 11:24:53 PM »
Alan, there can be this amount of variation with two chassis dynos.  Tire condition, how tight the bike is tied down to the dyno, the operator's individual methods, etc.  It is nothing to worry about if all other engine health indicators are OK.

 

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
Re: My first dyno run...I am soooo happy!!!!
« Reply #4 on: January 02, 2012, 11:42:56 PM »
I did a bunch of reading, apparently the loss of torque  maybe normal, especially when taking a stock engine and pushing it for more peak hp... I'll have to wait till I get it back on the Island to bring it back to the baseline dyno to see how it actually compares.  I dont know rpm for the news values yet....

Once the carbs are dialed in, what kind of performance gain might it possible to get from ignition tuning? 1-4%???  Justa general number, I know theres alot of variables to take into consideration, i am just asking about a general idea of how many more ponies we can might wring out.  I know my mechanic knows how, I am asking here because he's in a different state and it costs me nothing to ask here.  If i ask at the shop somehow he'll find a way to charge me for his time ;-)
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
Re: My first dyno run...I am soooo happy!!!!
« Reply #5 on: January 04, 2012, 08:43:27 PM »
hope this works, its a pdf of my 1st dyno pull...some room for improvement is evident
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: My first dyno run...I am soooo happy!!!!
« Reply #6 on: January 04, 2012, 08:47:38 PM »
"Pushing"?  Did you do any tuning between the dyno runs?

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
Re: My first dyno run...I am soooo happy!!!!
« Reply #7 on: January 04, 2012, 08:53:37 PM »
uhm, yes

everything

cams,
carbs,
pistons,
rods,
intake porting,
exhaust,
ignition module,
diet (both me and the bike)
 on
 and
on

I say pushing because at a 20% increase over stock, I am guessing we are nearing the limit with bolt on parts.  To get more we would have to do more physical engineering (ie boring, machining etc)
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline RansomT

  • Sr. Member
  • ****
  • Posts: 559
Re: My first dyno run...I am soooo happy!!!!
« Reply #8 on: January 04, 2012, 09:39:33 PM »
Could be because it is really lean.

Offline fredvance

  • FVANCE
  • Hero Member
  • *****
  • Posts: 2297
    • Vance and Forstall Racing
Re: My first dyno run...I am soooo happy!!!!
« Reply #9 on: January 04, 2012, 09:46:28 PM »
Really lean. Should be in the neighborhood of 12.6-12.8
WORLDS FASTEST PRODUCTION MOTORCYCLE 213.470
Vance&Forstall Racing
WOS 2011 235+MPH
Engine by Knecum, Tuned by Johnny Cheese.
Sponsers Catalyst Composites, Johnny Cheese Perf, Knecum Racing Engines, Murray Headers, Carpenter Racing

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: My first dyno run...I am soooo happy!!!!
« Reply #10 on: January 05, 2012, 09:30:45 PM »
It seems that your standard motor put out 57 hp with 52 pounds foot torque and your modified one makes 68 hp with 47 pounds foot torque.   Hopefully I am interpreting this right.

It is possible to get more peak hp with less peak torque.  The graph shows some data from 2010.  Everything was identical except for the intake.  In one set of runs I used velocity stacks and in the other set there were pod filters on the carbs.  The pod filter setup put out 68 hp and the stack setup made 71 hp.  Note how the pod filters produced more torque than the stacks.  The stacks moved the torque curve a few hundred rpm higher and they made more hp with less peak torque.

 

Offline firemanjim

  • Sr. Member
  • ****
  • Posts: 400
Re: My first dyno run...I am soooo happy!!!!
« Reply #11 on: January 06, 2012, 01:33:42 AM »
Depending on his comp ratio he may not need to go to 12.6,Fred. That is actually a bit rich. Around 13.2-13.6 may be better. But looked like he headed to 14+ in the upper rpms and that was lean.
Bonneville 2001,2002,2003,2004,and NO stinking 2005,DLRA 2006, next?
Well,sure can't complain about 2008--6 records over 200 and 5 hats from Bonneville,Bubs, and El Mirage for the team!

Offline Vishnuatepork

  • Full Member
  • ***
  • Posts: 79
Re: My first dyno run...I am soooo happy!!!!
« Reply #12 on: January 06, 2012, 05:24:04 AM »
my compression ratio is 12:1
suzuki vx800, 41mm FCR, shrink ported head, mega cycle cam, singh grooved head, custom headers, Supertapp exhaust, Ignitech ignition module, vs1400 drive hub, nology coils, magnecor wires, 12:1 cp pistons, carillo rods

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: My first dyno run...I am soooo happy!!!!
« Reply #13 on: January 06, 2012, 11:12:24 PM »
The Triumph shop who helps me does my dyno work.  The fellow who runs the dyno sets the jetting to produce maximum power rather than to a desired air fuel mixture.  It works.  The bike runs great.

Offline jacksoni

  • Hero Member
  • *****
  • Posts: 1524
Re: My first dyno run...I am soooo happy!!!!
« Reply #14 on: January 06, 2012, 11:25:42 PM »
The Triumph shop who helps me does my dyno work.  The fellow who runs the dyno sets the jetting to produce maximum power rather than to a desired air fuel mixture.  It works.  The bike runs great.
Absolutely right. Give the engine what it wants. Don't be trying to shoot for some "magic" AF number. There is none. Just changing the fuel could change what it wants, let alone all the other possibles.
Jack Iliff
 G/BGS-250.235 1987
 G/GC- 193.550 2021
  G/FAlt- 193.934 2021 (196.033 best)
 G/GMS-182.144 2019