Yeah, you can get huge differences between dyno's, Maz... Particularly between different type of dyno's. The DynaPack is probably the most "repeatable" dyno design, so it is great for determining if a mod hs generated HP or not, but it will definitely read higher than the other designs. This is mainly due to the fact that you have to remove the rear wheels to attach it to the dyno, so you effectively eliminate some of the drivetrain losses and reduce the rotating mass. With a DynaPack, your drivetrain lossed are typically only about 7 or 8% (just a rule of thumb and in no way accurate), so if you take take 289 and divide by .93 you get apx 310 flywheel HP (316 with the K&N)... so, fairly close to the factory figure of 306... . Where aswith a DynoJet, you leave the rear wheels on and you still have all of your drivetrain losses, which are typically around 15% (again these are all rule of thumb numbers), so take the 269 HP (with the K&N) and divide by .85 and you get 316.5 HP, which is almost exactly the same as the DynoPack with the K&N.

Just remember, you really need to stick with the same dyno for your baseline and final runs when determining if a mod gave you any measurable increases or not... and, preferably, do it on the same day and / or under the same weather conditions.


Yup, no arguments here, San... I like the DynoPack because thy seem to be the most repeatable of any dyno... I've had my car dyno'd at this same shop on 3 different days in the past 3 months and have pulled 294 EVERY time... is so close everytime it's almost crazy weird. Also, they did tell me to use a .93 (7% loss) multplier when using the DynaPack, since it will read higher than other dyno's, which seems to be pretty damn close to what I found... The guy that dyno'd my car also told me that the DynaPack typically reads about 8 or 9% higher than a DynoJet, which is almost exactly the difference I saw with my car.

Incidentally, both shops told me that my car posted one of the highest, if not the highest stock numbers of any HR motor cars that they have tested to date.

 

Yes, they should have absolutely disabled the traction control when dyno'ing... The traction control can most definitely negatively effect your dyno numbers. I remember when I first had my E36 M3 dyno'd and just disabling the traction control wasn't enough, it was still kicking in when thet dyno'd it (even with it off!!)... We finally ended up pulling the traction control fuse and my next dyno run was almost 20 HP higher!!! After realizing that the switch on the M3 didn't fully disable the traction control, I went back to the track (drag strip) with the traction control fuse pulled and ran a 13.6, which was .3 - .4 seconds better than with the fuse in and the switch off... my was 3 - 4 MPH higher too if I remember correctly. Needless to say, I never put the fuse back in until I sold the car. LOL

Thanksfully the witch in the G fully disables the traction control, so there is no need to pull the fuse.

Also, make sure that the use Manual mode when doing the dyno runs, so the car will hold the gear they use... also, have them try 2nd, 3rd, and 4th gear for the pulls, as the gearing can also effect the final output numbers (the difference isn't usually dramatic, but it's still something to think about) I think my car produced the highest numbers when in 3rd gear.

 

Thanks for everyone's input, this thread has been very informative so far. I think I need to try what 2GorNoTtoG said and disable my traction next time I'm on the dyno.

 

Your welcome.... Let us know how it goes. I'm just surprised that the guy dynoing your car didn't know to turn off the traction control.

 

ya +11 on the AT traction needs to be off and the slip light will be on either way because of the TQ converter locking up the tranny becasue it thinks the wheels are slipping. i have vids of my dyno but they keep getting deleted everytime i post them up on here. aka fail.

 

I think 2GoRNot2G has a 6MT which would automatically read higher than an AT. That would probably account for the biggest difference btw MKai0's dyno and 2GoRNot2G's dynojet numbers.

Of course, if 2GoRNot2G has an AT, well, consider yourself lucky that you have a VERY strong G.

 

This is very true ^. I think I'm gonna buy the HKS filters for the HR 350z and, drop them in and head back to the dyno!

 

I want a really strong G!

 

I'm actually an auto, but after driving Travis' (KulG35) car today, now I'm wishing I was a 6 MT! Now that is one fun G to drive!! Incidentally, Travis and I dyno'd together a while back and my auto pulled close to the same HP stock as his 6MT pulled with a full FI exhaust, HFC's, and intake. So, yes, I'm very happy I have a strong G.

 

Wow I think we need to get Dorothy and Toto on this one.....

jk sorry for the lame joke, this typo just made me chuckle, it was the highlight of a crappy day....

Good thread!
-Kregg

 

LMAO... Glad my crappy typing can help bring someone some joy. ;-)

 

hmm, really? what was your guy's Dyno numbers for both of you? Would love to see them, and compare.

 

20whp/30wtq for intake and HFCs sounds too high. Was this an A-B dyno, as in you dyno'd, immediately installed mods, and re-dyno'd.

If there was days in between then it is what it is, but still 20/30 sounds really high. Was the exact same dyno at the exact same shop? Same gear run? I could be off base here since I haven't looked into gains of HFCs, but I know intake is marginal at best. Haven't looked at UR either, but I can't imagine it's that high either.

If HFCs give you that sort of power, I'm ordering ASAP. Can anyone else clarify that these numbers sound realistic.

 

He has a UR pulley listed too, which could make up some of that difference.

 

I've heard that the HFC's can make up to 12 - 15 RWHP on the HR motor.. and I got 4 - 6 HP (5 peak) across the board from my K&N (same day, same dyno), so 20 HP gain is not out of the question... I'll know for sure if the Berk HFC's will produce those kinds of gains (at least on my car) once I finally get mine in and get them installed.