somethings not adding up? supposed to be stock but dyno sheets say otherwise

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lowlifexj

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Hi guys, I'm a new and proud owner of a 2000 vmax, originally imported from Canada, I think... originally had kph speedo not mph. it was supposedly sold to a us customer from the Sue St Marie dealer (still has key ring from that dealer on it). I bought it from the second owner, as far as I can tell, in Grand Rapids MI. So the guy I bought it from says its bone stock except for the steering stabilizer, clutch fibers and springs, led upgraded tail light, and shit light. What I'm having a hard time understanding are the dyno sheets he gave me when I bought the bike. 122hp??:ummm: i'll get them scanned and uploaded tomorrow so we can all see them but from what research I've done this doesn't add up for a stock vmax. the guy I bought it from did say it seemed faster than all his friend's vmaxes too.
 
Ha, did you buy that from Lee? if so, it is a fast bike, he beat the pants off me at Martin on it last year, was bummed when he sold it, get a hold of me and BeeKeeper if you wanna ride.
 
I was at the dyno day when that bike pulled 122hp and other on here saw it. I can tell you that bike pull's good on the street also. The best way to know for sure is come ride with us. Scuff and Beekeeper will chime in soon and maybe we can put a ride togather.
 
haha :rofl_200::rofl_200: I told you. Scuff has chimed in.
 
Keep in mind dynos are not particularly accurate. They are a great tool for tuning because they generally are repeatable, so same dyno same day can tell you how much a mod has improved power.

I've personally had my bike record 9 HP difference on 2 different dynos in the same week.

HP is also commonly measured to two different standards.....SAE and STD. STD will return higher numbers almost always.

You most likely have a very strong bike run on a slightly "happy" dyno.
 
Unfortunately there are ways to fudge the dyno numbers. One of the easiest is to use STD (Standard) VS SAE.

I borrowed this a cobalt forum, it explains it pretty good. SAE is the standard.

There are few standards used in the dyno world for gathering HP and TQ numbers, UNCORRECTED, SAE and STD. Uncorrected is NEVER accepted in the world of dynoing and tuning as it does not factor in any weather conditions etc. Now here is where the big debate comes...is between SAE and STD. SAE (Society of Automotive Engineers) is the MOST ACCURATE AND WIDELY ACCEPTED FORM OF MEASUREMENT when it comes to the world of dynoing. Here is some more info I have gathered between the two.....

A lot of people have been asking about SAE .vs STD Dyno numbers so I thought this would help. Most people know that showing STD numbers read higher but not many know why. SAE represents more realistic standard conditions, STD artificially boosts numbers.

Identifying Your Correction Factor:
Dynojet:
If you look at a dynojet graph in the upper right corner, you will see where it says the correction method being used. The options are SAE, STD, Uncorrected and a few not needed for discussion. You will also notice a smooth factor (up to 5) which dyno operators use to make the power curves and any other data displayed, such as AFR, seem more accurate and smooth. You will also see AFR graphs scaled DOWN to hide flaws in the curve.

MD:
A Mustang Dyno ONLY uses SAE Corrections. Smoothing can also be controlled as well as scale for the Graphical Outputs.


Overview:
Most of the stated horsepower numbers are “Corrected” values. The correction standards were developed to discount the observed horsepower readings taken at different locations and weather conditions. It is obvious that an engine builder in Colorado could not produce as much horsepower as a shop at sea level. There is just less oxygen for the engine to burn at the higher altitude. What are less obvious are the other weather condition effects on the engine. So in order to compensate for this all advertised horsepower is “corrected” to several different industry standards.

SAE:
"SAE (Society of Automotive Engineers), USA. Power is corrected to reference conditions of 29.23 InHg (99 kPa) of dry air and 77 F (25°C). This SAE standard requires a correction for friction torque.

STD:
STD is Another power correction standard determined by the SAE. Power is corrected to reference conditions of 29.92 InHg (103.3 kPa) of dry air and 60 F (15.5°C). Because the reference conditions include higher pressure and cooler air than the SAE standard, these corrected power numbers will always be about 4 % higher than the SAE power numbers. Friction torque is handled in the same way as in the SAE standard."



Here is some quick math (using assumptions and round numbers):

STD:
Air Temperature: 60F
Absolute Pressure: 29.92 inches Hg
Relative Humidity: 0%

Relative Horsepower : 104.8%
Air Density: 1.223kg/m3
Relative Air Density: 99.8%
Density Altitude: 67feet
Virtual Temperature: 60F
Vapor Pressure: 0 inches Hg
Dyno Correction Factor: .955

SAE:
Air Temperature: 77F
Absolute Pressure: 29.23 inches Hg
Relative Humidity: 0%

Relative Horsepower : 100%
Air Density: 1.157kg/m3
Relative Air Density: 94.4%
Density Altitude: 1952feet
Virtual Temperature: 77F
Vapor Pressure: 0 inches Hg
Dyno Correction Factor: 1
 
lowlifexj you got two great guy's near you to ride with and they ride a'lot and can show you a'lot about the vmax. You also have other great guy's all around mi that go on ride's togather so be ready to have a'lot of fun this year. This forum and other vmax forum's have a'lot of great people to ride with in and out of Michigan. On 6 25 15 - 6 28 15 We will be riding to Sumerset PA for a 30th anniversary vmax party. You won't want to miss it. And there is two cool guy's looking to split the cost on a room if you want to go cheep. You are more than welcome to ride down with us.
 
Also, they dyno operator can fudge just a bit, by putting less of a load on the bike, etc. Really the only way to know if that has happened, is to look into the dynojet program, and on the individual run, there will be a small mark by it.
 
Ha, did you buy that from Lee? if so, it is a fast bike, he beat the pants off me at Martin on it last year, was bummed when he sold it, get a hold of me and BeeKeeper if you wanna ride.

LOL! yes I did. And yes I would love to get with some fellow Michigan riders!
 
As for the dyno number's all i can tell you is the vmax i had was on that dyno before lee and he maid more power than me. I dont know what the torque was. I maid 118hp that day. I just did a dyno check on my b king and it showed 179.7 hp but i would say it was about 172 hp so dyno's can be different. But i know the vmax i had did pull a true 118 hp on a few dyno's so i dont know why that bike out pulled me but it did. I can also tell you that lee did not beat on the bike much when he had it. He's a laid back guy that's fun to be around. Like i said grab a full fist of throttle and come ride with us. Or better yet find a good meet spot for all off us and take us for a nice ride. Welcome to the forum ...................vmax-mike
 
thanks vmax-mike, I cant wait to ride with you guys. I spent a coupe hours just b.s.ing with Lee in his garage he told me to get on this forum and hit you guys up for riding.
 
I was talking to Beekeeper last night and he want's to go on a ride soon. We like to meet in Webberville mi. Or sometime's we meet in charlotte mi.
 
Mike is correct.
There were a LOT of Vmaxes dyno'd on that same dyno that day and most of the Gen 1 Stage7/Morley jetted and piped maxes put out around 123-125 RWHP.
So I'd say that Lee's 119-121 HP Dyno runs were accurate, he just has a Strong Stock Max.
My Stock 2000 put down 119 RWHP on 2 different Dyno's back in 2001 or 2002 and 2004, it's Not unheard of for a Stock Max to make that much power.
I also did a few 0-140 mph and 50-140 mph runs with a few Stage 7/piped maxes that same weekend and stayed right with them.
Here's a link to Lee's Dyno Sheet showing 119.8 and 121.2:
http://www.vmaxforum.net/album.php?albumid=712&pictureid=6607
 
Glad to hear you'll ride with us, now that I'm getting my carbs sorted I gotta get revenge on Lee's bike ! LOL :punk:
 
lol! You guys know more about this bike than I do! I cant wait to hear more... just don't tell me about the bad stuff:rofl_200:
 
oh don't worry nothing bad about his bike, if your into turning wrenches the mod monkey will be along soon !!!!!!!! if your smart you'll lock ur doors now !!! :rofl_200:
 
oh don't worry nothing bad about his bike, if your into turning wrenches the mod monkey will be along soon !!!!!!!! if your smart you'll lock ur doors now !!! :rofl_200:
Lock the doors.....and hide the check book
 
In the beginning I just laughed at the mod monkey, because I needed parts for this or that, but he is definitely getting his laugh on now! Heed the warnings and learn the lessons learned by your fellow Vmax brethren.

IMG_1471.jpg
 
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oh don't worry nothing bad about his bike, if your into turning wrenches the mod monkey will be along soon !!!!!!!! if your smart you'll lock ur doors now !!! :rofl_200:

what mod monkey?!?! the attached pic is my first build, '82 XJ650J Maxim started from scratch with stock non running bike... the Maxim almost tipped over when I pulled the Vmax in the garage and parked it next to him. I thought he would be mad but I guess he always wanted a big brother so its all good:punk: and I have to say my garage looks bad ass with two grey/blacked out bad@ss bikes in it!!!:thumbs up:
 

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