Competition Dyno Corrections or not!

[Jim Fulmer]

Dyno Number Corrections or not!

Having the day off gave me some time to re-dyno after the Canada trip so here is the question, what are the big number guys using for Dyno numbers? Mine were a good size change the weather was odd here today I made 2 runs and the numbers are as follows. I looked back on some of the runs in the data base from the past and I see that some change as little as 2 hp corrected.



Actual Horsepower 679. 5 and 681. 5



SAE Horsepower 708. 6 and 709. 6



STD Horsepower 720. 6 and 721. 8





All runs are on a Dynojet 248, I don't see a 720 but the number was there, opinions are wanted.



Jim

 

[Idaho CTD]

Jim,



I usually post my SAE numbers. That being said I think uncorrected numbers are a truer way of keeping track of things and comparing trucks, granted at higher elevations or places with high humidity some of the correction is needed. For example: One day I dynoed at over 90* and had a 13% correction factor. The run was 693hp. The next day was in the 70's and the correction factor was 8% with 700. 1hp. Uncorrected I made 30+hp yet it wouldn't seem like it if you looked at the corrected numbers. The SAE numbers are the ones usually given at the dyno shops I have been to therefore they are usually used.



Nathan

 

[HVAC]

Altitude has the greatest effect on the corrections factor. Seems readings are fairly close at 2000' or below. But in Denver:--)

 

[R.ebel]

Correction factor

I agree about the high elevation correction factor, but consider the following... at my hometown elevation of 6000 ft my truck makes 45 psi during a good hard pull with a B1 turbo with a non-wastgated exhaust housing. If I go to near sea level conditions I can get 53 psi under similar conditions. The denser air really makes a big difference, to the tune of 8 psi.



At a recent dyno event I heard a rumor that DynoJet has come out with a new dyno for diesel trucks with 7000# rollers and revised correction factors for turbo'ed engines. Can anybody confirm this?

 

[Jim Fulmer]

HVAC, the conditions were temps in the 75 degree range but the humidity was real high(90% or so) and it's 1300 ft here.



Rebel, I wish you could run on Piers's dyno! I just love the way it loads my truck down, gives you a better idea of what EGT's and Air temps are like, I wanted to run locally again as I need closer data for a new set of Twins.



Jim

 

[HVAC]

Boost is important no question.



I would point out that a certain truck ran 100 psi in Vegas on Friday as compared to 95 psi in Phoenix. Vegas is higher but it was also cooler. So, there a few things that effect the correction factor and performance.



The thing is that altitude is a constant. So, for the same atmospheric conditions at 6000' you will have a serious fudge factor compared to sea level. The correction factor is a bit overly generous for our turbo motors. Things being equal, you are going to have better corrected numbers in Denver then San Francisco. To a fault IMO.



Best thing is to dyno at the same facility whenever possible. If you dyno at other facilities with different brand dynos at different elevations, stuff ain't gonna be the same.



The non corrected numbers may be closer to reality for those at altitude.

 

[Jim Fulmer]

That's some good info, talking about boost those were at 60 psi, I made the first pull at 60 on the second I put 2 rounds on the wastegate... ..... and 60 psi again... . didn't try to blow anything up, I can make 65/70 or what ever on the road... ... . silly thing makes 600 hp at 130 MPH.



Jim (I'm just learning)

 

[HVAC]

silly thing makes 600 hp at 130 MPH

You better file a flight plan if your going to be going that fast!

 

[Sled Puller]

I don't believe the SAE correction factor applies to turbo Diesels.



ljthawk has made some excellent posts on the Ford site, and Diesel- central about this.

 

[Doubleclutch]

You better file a flight plan if your going to be going that fast!

 

[Jim Fulmer]

You better file a flight plan if your going to be going that fast!



130 isn't that bad but the 145 run I did was spookie.



Jim

 

[TxDieselKid]

Originally posted by Jim Fulmer

You better file a flight plan if your going to be going that fast!



130 isn't that bad but the 145 run I did was spookie.



Jim

At the DFW dyno day, Merrick made one all the way to 160! :--)





Andrew

 

[Jim Fulmer]

I didn't say anything about doing it on the dyno, I meant on the road.



Jim

 

[MMeier]

:-laf :-laf :-laf Howdy there Jim, how you been ?

 

[Sled Puller]

Originally posted by Jim Fulmer

I didn't say anything about doing it on the dyno, I meant on the road.



Jim

Please don't encourage Merrick to do that on the street!!!!!!!!!!!



I worry about that kid... ... ...



Don't want any B. O. M. B. casualties!!

 

[TxDieselKid]

Originally posted by Sled Puller

Please don't encourage Merrick to do that on the street!!!!!!!!!!!



I worry about that kid... ... ...



Don't want any B. O. M. B. casualties!!

Try riding with him! Actually I think the worse ride was with Kendrick.



Andrew

 

[Sled Puller]

404hp was a scary ride?

 

[TxDieselKid]

Originally posted by Sled Puller

404hp was a scary ride?

No, the ditch in the feild that he almost drove into after doing a burnout after a ride was comming VERY fast though.







Mr. No-since of adventure himself,

Andrew

 

[HoleshotHolset]

Apparently you've never ridden with J. R.



Last time I was in a truck with him behind the wheel - he was trying to measure the distance between his front bumper and Merrick's rear with a feeler gauge.



Matt

 

[Hammer]

Andrew...

Guess you never asked Gene about my wheel job of his ride right after he got it from EEP. The claw marks from his fingers are still embedded into his dash on the right side still. I still can hear his voice telling me that its HIS 800 number on the side and tailgate not mine. . ... LOL... ..... Andy