Dyno Days open house this weekend.

[juicedimpss]

no i just stated that the trucks were in a similiar situation for the sake of argument. yes they had dyno runs on the exact same dynos before and after mods. we were just trying to understand where the problem lies. yes we all thought his numbers should have been higher but also we know they were 2 different dynos, it's more that for the hp put down the tq doesn't quite fit. it's kind of confusing how his hp stayed the same and tq went down with better/more tune. i know i'm fairly new to dyno's but even some other guys there with a diesel thought it looked funny.

maybe there is something that just isnt right with that truck?

[BAD LS1]

Im not trying to create a debate or argument with all this, so lets keep this thread to a roar please. The points about the dyno types etc have been made. every vehicle that dynoed there recently and dynoed again this weekend all made around the same power, granted they are spark-ignited gasser's though. Diesel's really are a whole diff animal with special needs when it comes to dynoing them seems to be concensus. The pulls were all done equally to keep things fair, being its a competition after all.

[WickedSix]

The graph shows peak torque and peak hp ~100 rpm apart...I'm sorry but diesel engines just don't do that. Big torque happens down low and HP peak is usually right near redline. The point here is more along the lines of figuring out what could be improved to more accurately represent these trucks power levels. The truck audibly and visibly rolled into power faster the third pull, the additional power in the tune has been proven on the road...but it didn't show save for a 1 that is ONE hp increase on the dyno between the second and third run. The whole point was to figure out where it went wrong. It'd be nice to be able to use that dyno to test tuning on these diesels...brad is offering a heck of a deal for 3 pulls..but if it can't read it then what is the point? Thats what we have been driving at here....

[BAD LS1]

Were the runs done in a 1:1 ratio gear? If its a lower gear the #'s WILL be less. They figured that out on one of the 6 speed allison trucks.

Not sure how the computer can botch the math though...........

[juicedimpss]

The graph shows peak torque and peak hp ~100 rpm apart...I'm sorry but diesel engines just don't do that. Big torque happens down low and HP peak is usually right near redline. The point here is more along the lines of figuring out what could be improved to more accurately represent these trucks power levels. The truck audibly and visibly rolled into power faster the third pull, the additional power in the tune has been proven on the road...but it didn't show save for a 1 that is ONE hp increase on the dyno between the second and third run. The whole point was to figure out where it went wrong. It'd be nice to be able to use that dyno to test tuning on these diesels...brad is offering a heck of a deal for 3 pulls..but if it can't read it then what is the point? Thats what we have been driving at here....

1 peak or 1 average hp difference? I can see a cleaner tune rolling the drum quicker and being a faster truck on the road with the same(within 1 hp) peak power.just a thought.

[WickedSix]

well that would be 4th on the allison...but idk what it was run in on the dyno

[Monstr913]

it was run in 3rd thats what it was run in at huckstorf...i'm not saying i want my money back or anything like we said were just trying to figure out where the problem is either my truck or the dyno and from past dyno runs to me its the not my truck...it might be my truck but numbers don't match as we've said, and i have the best tuning before going to custom...and as for the bragging rights comment telling me to go to the track i do go but it gets old after a while and the dyno #'s and track times help me identify issues with my truck...now if WBD wasn't so far out i might go back on off day and run truck on old tuning and see if puts down close to other dyno runs just with better fueling system which was my problem which identified at last dyno run...and yea diesels are real different then gassers even if gasser is turbo

[bobo]

Wow. You guys need to do some research. VVT chargers are a PITA to tune on a dyno unless you load them properly. An LB7 is not as bad to tune without a load, but still needs to be in the correct gear for the dyno. 5th gear on a nonload cell dyno, and 4th gear with a load cell are pretty much the standard gear choices for running a Dmax/Allison on a dyno. I've dynoed a lot of diesels. If you want some help, just ask. I don't see any reason Huckstorf would dyno in 3rd. They have one of the best diesel dynos money can buy. It can load a truck up to 1500 hp and 3000tq.