hi guys, i have a friend with a private shop that just purchased a four wheel dynapac dyno set up about a month or so ago. I had my 97 JDM ITR over there on Saturday since he hadn't seen it yet, and he asked me if I wanted to hook it up and see what #'s it is putting down.

the dynapac has hub adapters that bolt onto each of the drive wheels, and those hub adapters slide into the dynapac boxes. It is not a roller dyno, but it can simulate load based on vehicle weight, etc... (unlike a crappy dynojet).

We guestimated the weight of the car at about 2600lbs, put in the final drive of 4.785 (it has a N3E stamp on the transmission), put the car in 4th gear, and let it do its thing. The barometer was at 25 (whatever the hell that means), air temp was high 50's or low 60's, and altitude here is over 5000 ft above sea level.

The car put down 138 whp, which is supposedly a corrected #, and what it would put down were it at sea level. I don't know how that's possible though since a friend of mine with a SiR2 B16A swapped EK with I/H/E and ITR cams put down 140 whp. After the car was back off the dyno, I remembered that the air filter is very dirty (car only has 35k miles on it), and another friend of mine said I should probably also advance the timing all the way since we are at such a high altitude.

- any other suggestions to improve the output of my car, or ideas as to why the #'s would be so low? (i was expecting 160-170 whp corrected for altitude, since the factory rates my car at 205ps at the flywheel)
- i know this is a dumb question, but do I move the distributor toward the firewall or toward the radiator support to advance timing? is this even a good idea at all?
- what #'s have other stock ITR's put down on a dynapac?

Thanks guys!

-T

 

no one has any input?

 

I put down around 160 -165 HP on a Dynapack Evolution 4000. In Phoenix we are at about 1200 ft above sea level. My mods are Mugen intake, header, exhaust, ECU and a Kakimoto resonated testpipe. Here is a link to my dyno comparisons that were done a couple of months ago.

https://honda-tech.com/zerothread?id=1448549

 

do you think i/h/e plus an ECU tune on stock internals are worth 30 hp over my car? i really should just put in a new filter and advance the timing (if advised) to see what it does afterward.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by YumVTEC &raquo;</TD></TR><TR><TD CLASS="quote">do you think i/h/e plus an ECU tune on stock internals are worth 30 hp over my car? i really should just put in a new filter and advance the timing (if advised) to see what it does afterward.</TD></TR></TABLE>

All chassis dynamometers are slightly different. There are too many different variables to take into consideration to compare numbers on different dynos. Also, Dynapack dynos tend to read lower than other types. I have had tons of experience testing on Dynojets and Dynapacks dynos and have seen a large difference between the two types. Did you guys setup the gear ratio in 4th gear for your car before you started testing on the Dynapack? If you input the wrong gear ratio in the dyno before starting your numbers will be skewed. Unless you test the cars on the same dyno the results are pretty much meaningless.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98 Spec R &raquo;</TD></TR><TR><TD CLASS="quote"> Unless you test the cars on the same dyno the results are pretty much meaningless. </TD></TR></TABLE>

Agreed. Just a note, the Dynapack doesn't give you wheel horsepower, it gives you hub horsepower. I (and almost every OEM) like the Mustang dyno because it simulates the actual load that driving the car on the road would create (including rotational inertia created by the wheel/tire assembly, and drag created by the friction of the tire against the rollers). Most test labs also use the Mustang dyno for that reason.

 

yea did you make sure the gear ratio was right? that could make a big difference...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. Helsinki &raquo;</TD></TR><TR><TD CLASS="quote">

Agreed. Just a note, the Dynapack doesn't give you wheel horsepower, it gives you hub horsepower. I (and almost every OEM) like the Mustang dyno because it simulates the actual load that driving the car on the road would create (including rotational inertia created by the wheel/tire assembly, and drag created by the friction of the tire against the rollers). Most test labs also use the Mustang dyno for that reason.</TD></TR></TABLE>

the dynapack can simulate load just like most other dynos, it just does it through an internal hydraulic brake system in the boxes, instead of using big rollers.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98 Spec R &raquo;</TD></TR><TR><TD CLASS="quote">

Did you guys setup the gear ratio in 4th gear for your car before you started testing on the Dynapack? If you input the wrong gear ratio in the dyno before starting your numbers will be skewed. Unless you test the cars on the same dyno the results are pretty much meaningless. </TD></TR></TABLE>

it doesn't ask for gear ratio on the car setup screen, it only asks for final drive and the gear # that we will be in. all the cars he has put on have been reading low in my opinion. maybe we are f'ing up the setup somehow. any advice?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by YumVTEC &raquo;</TD></TR><TR><TD CLASS="quote">The car put down 138 whp, which is supposedly a corrected #, and what it would put down were it at sea level. I don't know how that's possible though since a friend of mine with a SiR2 B16A swapped EK with I/H/E and ITR cams put down 140 whp. After the car was back off the dyno, I remembered that the air filter is very dirty (car only has 35k miles on it), and another friend of mine said I should probably also advance the timing all the way since we are at such a high altitude.


-T</TD></TR></TABLE>

my 00 si stock dynoed that much power, should get your car checked out at the acura/honda dealership...i've seen type r's dyno avg at mid 160's to low 170's stock....

 

some eye candy for my ITR brethren (sorry for no re-size, i'm crunched for time heading out the door to lunch):

 

how do you dyno with no wheel?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by import810 &raquo;</TD></TR><TR><TD CLASS="quote">how do you dyno with no wheel?</TD></TR></TABLE>

That is a dynapack dyno. It attaches to the hub.