and that's why I always try to tell peoples to not get too wrapped on a dyno, and I know first hand how easy those numbers can play with you. You go to the dyno and you expect one thing but come out with a dissapointment. I know all about those feelings pretty good.

Unfortunately, in a world of modding there's no way to get around a dyno. I guess one can hit the track every single time you add or delete a mod but there's no guarantee that our foot will be programmed to work the same exact way on every single run either, and especially if we have to use both of our arms and legs.

At the end of the day a dyno can be a very useful tool. We just have to be realistic about what to expect and well informed.

That was a nice article mike:thumbsup:

Dyno Correction Factor
So what's all this correction factor stuff anyway??
The horsepower and torque available from a normally aspirated internal combustion engine are dependent upon the density of the air... higher density means more oxygen molecules and more power... lower density means less oxygen and less power.
The relative horsepower, and the dyno correction factor, allow mathematical calculation of the affects of air density on the wide-open-throttle horsepower and torque. The dyno correction factor is simply the mathematical reciprocal of the relative horsepower value.
Originally, all of the major US auto manufacturers were in or around Detroit Michigan, and the dyno reading taken in Detroit were considered to be the standard. However, as the auto industry spread both across the country and around the globe, the auto manufacturers needed a way to correlate the horsepower/torque data taken at those "non-standard" locations with the data taken at the "standard" location. Therefore, the SAE created J1349 in order to convert (or "correct") the dyno data taken, for example, in California or in Tokyo to be comparable to data taken at standard conditions in Detroit.
What's it good for?
One common use of the dyno correction factor is to standardize the horsepower and torque readings, so that the effects of the ambient temperature and pressure are removed from the readings. By using the dyno correction factor, power and torque readings can be directly compared to the readings taken on some other day, or even taken at some other altitude.
That is, the corrected readings are the same as the result that you would get by taking the car (or engine) to a certain temperature controlled, humidity controlled, pressure controlled dyno shop where they measure "standard" power, based on the carefully controlled temperature, humidity and pressure.
If you take your car to the dyno on a cold day at low altitude, it will make a lot of power. And if you take exactly the same car back to the same dyno on a hot day, it will make less power. But if you take the exact same car to the "standard" dyno (where the temperature, humidity and pressure are all carefully controlled) on those different days, it will always make exactly the same power.
Sometimes you may want to know how much power you are really making on that specific day due to the temperature, humidity and pressure on that day; in that case, you should look at the uncorrected power readings.
But when you want to see how much more power you have solely due to the new headers, or the new cam, then you will find that the corrected power is more useful, since it removes the effects of the temperature, humidity and atmospheric pressure and just shows you how much more (or less) power you have than in your previous tests.
There is no "right" answer... it's simply a matter of how you want to use the information.
If you want to know whether you are going to burn up the tranny with too much power on a cool, humid day, then go to the dyno and look at uncorrected power to see how exactly much power you have under these conditions.
But if you want to compare the effects due to modifications, or you want to compare several different cars at different times, then the corrected readings of the "standard" dyno will be more useful.

I gotta tell ya... This makes very little sense to me. I'm not sure how there are a couple handfuls of dynod on that graph that have that additional correction, and if I'm not mistaken, on the same kind of dynos. How are those determined different, because I see no graphs saying how they were adjusted. Not arguing, but not getting this extra adjustment, without a graph to shoe how it was tested. I know those #s now start to match up against what Rod1 has posted in the LLT FI list, with comparable mods(actually less) and I thing the torque explains itself, because the gears bring the power up in the rpms. I guess ill never know, but I'm not sure we are comparing apples to apples here. Again, just my humble opinion. I really only went to baseline, but now with all these adjustments... I don't know how much I buy any of these numbers.

Don't let the dyno numbers confuse you too much. At the end of the day dyno numbers are just that a number. Just because you see someone put down 230 stock and another 265 does not mean the one that put down 230 really has less power. You actually have good numbers. Right around what we have been seeing with your level of mods. The baseline you established will now be the comparison factor to all future mods you install. Only try to focus on your dyno numbers. No 2 dyno are never the same.

Welcome to the world of dyno:laugh:

Is there another dyno thread? I thought I posted my dyno with 100shot somewhere. I can't find it now.

as a matter fact, I think I remember seeing your 100shot dyno somewhere a while back while I was looking through the forum. I will see if I can find it for you and post and update on the front page;)

Thanks. I know the dyno was done on oct 7th. I can't remember when I posted it though.

Actually, if u want to wait to update the OP, I'm going to dyno my car dec 3rd and get torque numbers.

getting mine done tomm a before and after as I am installing BBK LT with HFC

I'll be doing the same on Friday. BBKs with HFC's going on.

I can do that but if I find it before the date i will upload the old one as well.

Can't wait to see you guys numbers
:thumbsup: I am also about to update and redo the whole list when I have some time. If you guys can please post the actual graphs along with numbers.

It's going to be hell going through the forum and looking for everyone's graph but I think it will be well worth it.

awesome, I hope they give as much power as the claim is.

Can't wait to see you guys numbers
:thumbsup: I am also about to update and redo the whole list when I have some time. If you guys can please post the actual graphs along with numbers.


Yep will def get it done right this time. I hoping for some some really good numbers, especially since I did not load( I think) the updated tune properly before my last dyno. plus now I have the vararam and Vmax TB on it. So hoping for something better than my first dyno which was 265hp, with just an air raid, solo hfc

heh, finally found it! It was in the Join LLT thread:facepalm:

sorry for the sideways pic. lol :facepalm: :facepalm:

http://tapatalk.com/mu/a6cd0bd3-7348-49b8.jpg

Edit: oh, and it was about 80 degrees out, 3rd gear pull, manual tranny.

Our DynoJet 224xLC has already done the corrections for our elevation and it has factored in the weather conditions using the SAE standardized correction factors. If you were seeing real #'s they would be far lower at our awesome 4500 FT elevation. I have a bunch of stock to simple bolt-on LLT auto/manual baselines if you'd like to have a comparison.

Our dyno is only 3-4 months old and it is calibrated but a DynoJet, Mustang Dyno, Dynomite, Dynapak and whatever else is out there will all be a little different. The important thing to remember is a dyno is a good tool to get a starting point, end point and to get a tune dialed in.

Please feel free to call, email or PM me anytime with questions. Once the tune is dialed in a little better you'll see better #'s also. :chevy:

Kind regards,

Jordan Priestley
888.308.6007

Nice to actually see the pros clear things up. Did you say 4500 Elevation? Yikes..

ok here is my first run, will say that I am very disappointed in these numbers

temp-49 degress

time 10am

humidty -70%

gear used 4th gear

Model Dyno- Dyno mete- not sure of the exact model, but it was pretty old

AFR-13.3

Mods at the time , Vmax RB, trifecta tune. solo hfc, vararam

NO SAE Correction

HP was 246 and tq was t33

next was done after the BBK LT withy HFC,

all variables were roughly the same down to the AFR being 13.3

HP was 251 and tq 238

One again no SAe correction

So I am at a loss what exactly is going on here. I know I need to get Vince a data log to see if any tweaking can be done but something is wrong. Or is it okay

Only gained 5hp? Yeah that sounds wrong.

you are running too lean, i believe. you should be around 12.1. maybe someone can chime in that knows for sure. that should give you some more hp.

I think that sounds right.

Yea I think something is wrong mydreamcar and you may need to log some runs for Vince to tweek your tune. Also do the ASE correction on you runs. Cause I got 17rwhp with just intake and axleback on a hot 98* day :iono:. If you need help doing the conversion I'll help you out buddy.

Thats what I thought. but the place I went that did the install felt it should be closer to 14.3. Gonna ned vince to fix that, gonna datalog a run tonight and send off to vince, I was figuring an easy 270 to the wheels

Yea I think something is wrong mydreamcar and you may need to log some runs for Vince to tweek your tune. Also do the ASE correction on you runs. Cause I got 17rwhp with just intake and axleback on a hot 98* day . If you need help doing the conversion I'll help you out buddy.

Cant C Me, that would be great as I am lost with conversion think. I knew there would be some extra in there just not sure how to do it

I will say, guy does great work, but the Dyno he was using seemed very old,. it was moveable and he just attached some ramps to it. I kinda thought that Dyno's should be mounted into the ground

Higher than the balls on a Giraffe! :bellyroll:

The LLT V6 likes to be around 12.4 - 12.6 AFR from what I've seen personally.

We did an auto with an Airaid CAI and Magnaflow axle-back and the baseline before we installed the ARH LT's w/catted x-pipe was 242.65 RWHP and 228.76 RWTQ. We then installed the ARH LT's with the catted x-pipe and we got 261.33 RWHP and 249.13 RWTQ for a solid gain of 18.68 RWHP and 20.37 RWTQ. The runs were performed on the same day. We then did a Trifecta tune and the final #'s were 265.21 RWHP and 259.37 RWTQ. The tune gained 3.88 RWHP and 10.24 RWTQ.

Headers Run # 3 and the Headers and Trifecta Tune Run # 10
http://farm7.static.flickr.com/6049/...8dcf3845_b.jpg

The largest benefit from the tuning was the torque management adjustments, Rear o2 error codes "adjusted for the header" and the shift points. Please feel free to call, email or PM me anytime with questions.

Kind regards,

Jordan Priestley
888.308.6007