neither,... it depends on the tuner and the driver and few other 100 variables

 

18 psi on pump gas, yes..Im saying that you would need to pull so much timing that it would be about 500-525 DD.

 

I came out like 460 on JER's DD last week..and was around 540whp at GTM's dynojet...so now I just say 500 wheel when someone asks...

 

There should be a DD dyno close to you some where..no?

 

Looking forward to Bullitproof's DJ comparo-I beleive most DP's are set-up to read much higher than DJ's, at least thats what Ive noticed in my experience and fro mwhat Ive seen. 600whp on a DP Id guess would be 550 or less on a DJ SAE or STD corrected.

Julian-your numbers dont surprise me, I did the ocmparison over 1 year ago within minutes of each other from dyno to dyno-simialr results for me. What did surprise me is how close YOUR correction was on your DD to simulate DJ #'s, not bad to give people "an idea"....

 

Make it simpler.. Same tuner same car and same driver..

 

I also did a comparo using your numbers, and sharif's dyno. What we calculated was that Sharif's dyno was about 7% less than a Dyno jet.But about 7% higher than our dyno..Possibly related to the atmosphere and sea levels in different reigions. He is closer to the equater and may get lower barometer readings.

 

Kind of a silly Q, but here is my answer. I assume your talking drag racing, Id guess WOT tuning only both would be very similar in regards to the inertia vs load based, the DJ tuner could always go on the street and fine tune under load-at the expense of tickets, etc. A DD tuner could tune most if not the entire map on the dyno, he is essentially "road tuning" it on the dyno. 1/4 wise, again not looking at part throttle tuning, hiccups, etc, Id think the ultimate advantage would go slightly to a load based dyno but its slim to none.

Best answer is : best driver + set-up wins the race, it can be the difference of over 1 entire second in 1320 feet...

 

Yeah, I didnt notice your differences were greater until you mentioned my difference. Good comparo-goes to show people how much variance there can actually be between the two. At the end of the day 500whp on a DJ, DD, or even DP is fast and dyno's dont decide the winner, drivers do

 

and assuming the tuner is 100% confortable and great tuner with both DJ and DD
lol neither...

 

I used the dynojet at UTi around 10:00am and later on that day I used a Dyno Dynamics and same psi same a/f's the Dyno Dynamics read about 65WHP higher

280whp on a Dynojet 345 at the dyno dynamics.

I'm not arguing which one reads higher or lower, all I say is take it for what it's worth and the numbers you get will definitely be proven on the track

 

 

FunctionTuned has an analog DD similar to MRC's. They're out near Dulles. For a look @ the new windows DD take a trip up to MA-Motorsports in Baltimore. I can speak w/ the owners of both shops and arrange a time for you to stop by and play w/ the dynos.

 

Obviously that DD had a silly correction added in or the temp probe was malfunctioning/placed in a bad spot and the numbers were skewed...

 

If Im thinking right..thats around 18% . The DJ reads real high or the DD reads real low .

 

Was going to try and find another DD around town to do another test..but they're pretty hard to track down. Stillen wouldn't do it because they only allow kits they install to be dyno'ed and was woried about liability issues.

 

What shop is JER ?

 

World record - 4 pages in the FI section and zero TOS violations. A pat on the back for everyone involved in this thread.

Very good thread, didn't realize there was so much to dyno'ing a car - especially when considering tuning on that dyno. Keep it coming.

 

They're in socal...there's a thread somewhere here about them...very cool guys to deal with....

 

And yes he did trap 132 as i was running next to him(bastard )