RP Random Dyno Recert Results

[Todd Covini]

As you know, Team Pedersen/Marvel was the lucky winner in last weekend's random drawing for the Round 4 dyno recertification. The Top 5 cars from both AI & CMC weekend races were eligible for the random drawing. Following Chris Marvel's win on Sunday, his hood was sealed and the car required to report to the dyno.

This morning, I witnessed the recertification at Houston Performance and am happy to report that the car was found to be within limits.

Per the AI rules, the highest reading for HP and TQ was used after 3 pulls in succession. In the interest of full disclosure, here are the results:

321.5 HP (Pull #2)
325.8 TQ (Pull #1)

Accordingly, his minimum weight requirements are:
321.5 HP X 9.5= 3054
325.8 TQ X 9.0= 2932

Minimim weight requirement for Team Pedersen/Marvel is now 3054...post-race the car weighed 3108. Unless performance changes are made and a new dyno sheet presented, Team Pedersen/Marvel now has a 321.8/325.8/3054 official dyno decal.

The inspection was conducted on a Dynojet 248c, in SAE Smoothing 5, on software version 6.03. These recert pulls were ~10 HP/TQ greater than his official dyno decal and further stress the need to provide for ample cushion to accomodate for dyno & scale variance between events.

Great job to our random dyno recert winners Team Pedersen/Marvel, Eric Varner and Todd Covini for staying within the limits and winning races thus far in the season! Who will be the next random dyno recertification winner??? Stay tuned and see you at Hallett!!!

-=- Todd

[Mike Bell]

Todd et al:

Is there any possible way to get an official dyno selected in the Austin, Houston and DFW areas? (I'm just asking, the answer could be that it is not practical or possible.) This dyno variation thing is pretty difficult for me to grasp but if the condition exists can/should we make an effort to find dyno's that all seem to measure close to one another and use those exclusively? Perhaps we could use some of the AI/CMC funds on that effort since the random compliance checks seem to continue to validate that nobody is "over" the allowed limits.

I dont' care if they all read "low" (but those going to Nationals may care a bunch!) but having something of a yardstick is better than this variation issue IMHO. Seems to me that allowing the use of any dynojet is more cause for concern based upon the results we've seen/heard about thus far. We've built up quite a knowledge base about available dynojets in those metro areas, perhaps we could leverage that in an attempt to do some "dyno testing" using one car? Otherwise, just tell me where AG did his 230/288 pulls and that's where I'll go from now on! :wink:

[CMC17]

I truly doubt anyone will be caught over the limit. The random drawing does not deter those that are inclinded to push the limits. A self re-cert/annual is useless without a director or tech inspector on-site. Numbers can be manipulated at will. For those that are at or over the limit probably aren't worried. The results will be the same regardless which dyno is used. Having a piece of paper that "reads".. "I'm legal" means diddly. There are 101 ways to "fool" themselves, but a true testament to character are those that throw those 101 ways out the window and races without the "extra" power crutch.

But, what do I know.

Not interested in a pissing match either... just stating the facts. The way it is now.. dyno's are useless.

[Mike Bell]

Look, I'm not interested in a pissing match. I just want a place to go and consistently get numbers that won't get me tossed out or DQ'd plus be on par with my competitors.

Running 230/288 like AG is doing at 3150 min weight is pretty much telling me he's comfortable with the ability to reproduce those numbers when necessary. Doesn't matter if it's reading high or low, as long as it's consistent right?

[RichardP]

Before this gets too out of hand, I guess I should post the actual numbers.

The old numbers:
316.5 HP
320.0 Tq

That's a difference of 5 HP and 5.8Tq. The last dyno that was done was at the track on Saturday morning with a very fresh engine. It was run for the first time on Thursday night and only had the one session on track for break in. It was also heat soaked from being on the track while the recert was done with the car off the trailer.

I just don't see a big dyno variance here and I never have with one of my cars. I expected the numbers to be higher and they were.

Richard Pedersen
#91 LX5.0

[Mike Bell]

RP,

April 06 race report has your numbers as:
Pedersen/Marvel 312 314 2964

Perhaps that's where Todd got the ~10HP?

But the point still remains, until we get a set of dynos that read reasonably close to one another then EV's conclusion above seems more accurate to me than other conclusions. I tune for 230/300 on a dyno that's 3% low while someone else tunes on a dyno that's 3% high, guess who has more power come race day? In CMC I'd say that's worth chasing down.

[Adam Ginsberg]

At this time, selecting an "official dyno" is pretty difficult - shops come and go, dyno's get bought/sold, etc. No promises, but we'll discuss it.

If your hood gets sealed, simply go back to the dyno you were at earlier this year, Mike. That should provide repeatable numbers - although we all realize there is no guarantee.

FWIW, I dyno'd my car at Lou Gigliotti's. We believe his dyno reads a bit on the high side, and that was a good thing, IMO. I'm very comfortable with being able to reproduce that number on another dyno, and I suspect it will probably read lower.

Something else Daron and I do.....is keep the car a bit heavy. We typically come off the track right about ~3200lbs ( a bit more w/Daron in the car...like ~3210-3220 ), giving us a 50-60lb margin. At MSR-H, I came off @ 3185 after the 40min, which is just about right. For a 40min race, I fill the car all the way up, just to play it safe. That, coupled with the cool suit, keeps us where we want to be WRT weight.

[Adam Ginsberg]

Mike - you bring up an important point. It's well within a competitors grasp to "tune" to a specific dyno. However, that could come back and haunt them at some point down the road.

Someone dyno's on a low reading dyno, getting their 230/300, and comes off the scales @ ~3160. That competitor gets sealed, and is sent to a different dyno due to time, location, etc, and blows a 233hp.....now they are underweight, and DQ'd.

My preference is to always run a bit heavy, on the off chance a dyno reads a few HP higher.

[Mike Bell]

My understanding is that the competitor could go back to the dyno of their choosing (or their original dyno shop) for a certification compliance check. That not correct?

[Mike Bell]

Mike - you bring up an important point. It's well within a competitors grasp to "tune" to a specific dyno. However, that could come back and haunt them at some point down the road.

Someone dyno's on a low reading dyno, getting their 230/300, and comes off the scales @ ~3160. That competitor gets sealed, and is sent to a different dyno due to time, location, etc, and blows a 233hp.....now they are underweight, and DQ'd.

My preference is to always run a bit heavy, on the off chance a dyno reads a few HP higher.

It may be that there are too many variables to nail down that last 6% variation (or whatever percentage it turns out to be). I was just hoping that there was a dyno in each metro area where we could duplicate reasonable results to try and minimize the dyno as a possible source of variance.

I too carry extra weight, but at my current power levels it's not that important. As I work towards the competitive power levels I want to make sure of two things:

1.) That I don't go over - ever.

2.) That the numbers my competitors produce are similar.