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Author Topic: DYNO DIFFERENCES
pat slattery Verified Driver Made Donation to Website
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Anyone have the dyno HP variances between a Dyno Jet VS Mustang dyno. Basically if a dynojet which is pretty much the standard, shows 120, what could you expect to see on a Mustang dyno.

Thanks

Pat

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keeping the faith for the 1.6

Arrow Karts

T.J. Kearney Verified Driver
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And a Dynapak for that matter?

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Tom Kearney
SSM #85
*~*~*~*~*~*~*~

Mitch Taylor
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Newbie question re dyno, that is 120hp at the wheels, anybody know the loss factor for the driveline. Not a guess but diff between what has been seen flywheel vs rear wheels.

Kyle Freiheit
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quote:
Originally posted by pat slattery:
Anyone have the dyno HP variances between a Dyno Jet VS Mustang dyno. Basically if a dynojet which is pretty much the standard, shows 120, what could you expect to see on a Mustang dyno.

Thanks

Pat

answer to life the universe and dynos = 42 [laughing]

Gibscreen Verified Driver Series Champ
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I don't have the answer right now, but over the next few months I'll be on a Dyno Max, Mustang and Dynojet.

We did a baseline before an engine build on a Dyno Max so we're going back there to check power post-build. So I'll try to get back here after that to give an update on the variance.

After we did the baseline on the DynoMax we got access to very cheap dyno time on a Mustang so we'll do tuning on that.

Then we'll be on a Dynojet to get an official HP number for NASA's PTE class.

--------------------
Rob Gibson
RJ Racing
2010 NASA Nationals TTE Champion
2008/2009 WERC Champion
2007 NASA SoCal SM Champion
rjracing.net
Weekend-Racer.com

Gibscreen Verified Driver Series Champ
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quote:
Originally posted by Mitch Taylor:
Newbie question re dyno, that is 120hp at the wheels, anybody know the loss factor for the driveline. Not a guess but diff between what has been seen flywheel vs rear wheels.

The standard number used is between 15% and 20% but there is no "exact" number because every car is different. WHP measures what's actually put to the ground so it takes into account all drivetrAin losses, which include drag in the transmission, diff, axles, even tires. So every car is different.

Flywheel HP numbers are just for bragging anyway. [Wink]

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Rob Gibson
RJ Racing
2010 NASA Nationals TTE Champion
2008/2009 WERC Champion
2007 NASA SoCal SM Champion
rjracing.net
Weekend-Racer.com

Drago Verified Driver Made Donation to Website Series Champ
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I have gone to the track with the same car dynoing at the same dyno and have made 120/112 and 127/117. I was way too worried when it was 120 and way too happy when it was 127. Car raced teh same both days. Comparing dynos is impossible. Even Dyno jets vary quite a bit. I know a few in Texas that routinely read 7-8 hp lower than what most consider "right"

Pat,
If you want an accurate number... I think Rich at Backstreets dyno is the de facto "standard" We have almost all dynoed on his dyno. Not sure it will help, but you are welcome to all my files on his dyno. I make 126 here and made 126 there. I think that I would base your numbers off his dyno as most Runoffs competitors have history on that dyno.

Jim

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Jim Drago
East Street Auto Salvage
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EAST STREET RACING

TimBuck Verified Driver Made Donation to Website
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Which of course begs the question, "Is your driveline as loose as the guy you THINK is making more power?"

[duck]

Just because the guy that beat you (supposedly) out powered you down the front straight dosen't necessarily mean his engine is puting out more ponies.

--------------------
Tim Buck

MAZDASPEED Motorsports Development
Mazda North American Operations
phone (800) 435-2508
fax (949) 222-2650

zoom-zoom!

David Dewhurst
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This is interesting because I been thinking about the 123 hp 105 ft lb 1.6 motor with reference to all these same things. A guy/gal buys a noted motor that has the hp/torque numbers & you do some dyno work & the thing shows lower numbers. The questions get asked & everything gets blamed except the motor. Just saying. [Smile]

Let us not forget tires & toe on the drum dyno.

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Have Fun [Wink]

David Dewhurst
CenDiv
Milwaukee Region
Spec Miata #14

darmstrong Verified Driver
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Isn't there also a difference depending on whether you are running a Torsen or a Mazdacomp LSD rear end?

Dave

Bob Thornton - Race Engineering Verified Driver Made Donation to Website Series Champ
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I agree with Tim and Jim, none read the same. Good stuff guys.
We use 2 Dynojets and both read different.

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Bob Thornton
http://www.raceengineering.org
Race Engineering Championship Winning Engines

Teamfour Verified Driver Made Donation to Website
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quote:
Originally posted by Bob Thornton - Race Engineering:

We use 2 Dynojets and both read different.

If I bring my car to you to be dynoed, will you put it on the machine that reads higher? I have an inferiority complex. [Wink] [Big Grin]

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Lee Tilton
1993 Meowta #04
Brimtek Motorsports/ Team Four Racing
Team Four Racing

jmac36
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quote:
Originally posted by TimBuck:
Which of course begs the question, "Is your driveline as loose as the guy you THINK is making more power?"

[duck]

Just because the guy that beat you (supposedly) out powered you down the front straight dosen't necessarily mean his engine is puting out more ponies.

DING DING DING!! give that man a cigar!!!!

Gibscreen Verified Driver Series Champ
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I'm not sure the OP's question was ever addressed. For those who have used different types of dynos (Dynojet, Mustang, DynaPak, DynoMax), have you noticed any general tendencies for one type to read higher or lower than another, and if so, by how much? The responses will be anecdotal but if enough people have a similar experience we can start to come to some conclusions.

--------------------
Rob Gibson
RJ Racing
2010 NASA Nationals TTE Champion
2008/2009 WERC Champion
2007 NASA SoCal SM Champion
rjracing.net
Weekend-Racer.com

TimBuck Verified Driver Made Donation to Website
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quote:
Originally posted by jmac36:
quote:
Originally posted by TimBuck:
Which of course begs the question, "Is your driveline as loose as the guy you THINK is making more power?"

[duck]

Just because the guy that beat you (supposedly) out powered you down the front straight dosen't necessarily mean his engine is puting out more ponies.

DING DING DING!! give that man a cigar!!!!
601, Partagas, Romeo Y Julieta, H. Upmann... They're ALL good.

--------------------
Tim Buck

MAZDASPEED Motorsports Development
Mazda North American Operations
phone (800) 435-2508
fax (949) 222-2650

zoom-zoom!

Sean Allen Verified Driver Made Donation to Website
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Not with a Miata, but my old Subaru dyno'd at 273 awhp on a Mustang dyno, and a bit over 300 on a Dynojet.

Back from the tuner world, we always knew that Dynojets were there for bragging rights and Mustang/Dynapacks were there for real world numbers.

With a Miata, I have seen around a 20hp difference between Dynapack models 2000,3000, and 4000.

Rich Verified Driver
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The most my engine ever made on Backstreet's dyno was 117whp (brand new green Sunbelt, rounding up, '07 Runoffs). We found a couple on the dynapack the following season. So I figure my 1.6 was/is pretty close to 120 BackstreetHP when it's in good tune (with super-aerodynamic flat black SR-71 paint).

My car makes 103-105 horsepower on a Dynapack depending on weather, time of the month, and alignment of the planets. The dynapack I used is now owned by the "Dad, what's a" Scheiflers. We used an 8-second pull from I think 4000 rpm to 7000. Using a longer pull which more realistically reproduces the actual time it takes to get from 4000 rpm to 7000 rpm in 4th gear on track would produce more "dyno-jet" like numbers, but it would also heat up the car and dyno more and take a lot longer (because Miatas are slow). So we always used 8-second pulls for tuning purposes.

--------------------
Rich Wiese

Spec Wrecker Ford

Geri - aka LeadFootGurl -
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A bit of a novice question - the 120 hp you are discussing ... is that output by a 1.8 or a probuilt 1.6? I have a "geri-built-in-her-garage" 1.6 motor, more or less stock, just had it dynoed at 102 with upper 90s torque. Is that about right or am I at a considerable loss for what the motor is?

Are there significant differences between the more expensive probuilt motors vs. something remanned on ones own?

What kind of "tuning" would be recommended when trying to get the max out of the existing motor?

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=====
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Lance Snyder Made Donation to Website
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quote:
Originally posted by TimBuck:
Just because the guy that beat you (supposedly) out powered you down the front straight dosen't necessarily mean his engine is puting out more ponies.

I sure hope ponies aren't being put out... PETA would be pissed.

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All this has happened before, and will happen again

TimBuck Verified Driver Made Donation to Website
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People for the Eating of Tasty Animals???

--------------------
Tim Buck

MAZDASPEED Motorsports Development
Mazda North American Operations
phone (800) 435-2508
fax (949) 222-2650

zoom-zoom!

Rich Verified Driver
Oh, that's where that is.

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People for the Ethical Treatment of Automobiles, I think.

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Rich Wiese

Spec Wrecker Ford

   

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