Houston results changes for CMC

[Al Fernandez]

Prior to the recent Houston event, John Martin made some changes to his engine setup and needed a new dyno cert. His plan was to dyno at the track on Friday, but it turned out the dyno there was out of commission so he was unable to test. We sealed his hood at the end of the weekend and its taken a bit of time to set up a time to run the tests, which we finally did this past Saturday. Unfortunately John broke over the limit on the dyno. We'll have NASA official results changed to reflect John as having fun run the weekend and not collecting points. However, since we are so close to the deadline for Toyo bucks, and since many of you have already submitted your forms, we will not make that change until after the Toyo submittal window passes. Instead, John will submit forms for his current finishing positions and will distribute cash to those impacted.

Here is the way I see it, please chime in with corrections:
R1
Gary Robertson moves up to 3rd and is owed $50
Daniel Records moves up to 4th and is owed $100

R2
Craig McCormick moves up to 2nd and is owed $200
Daniel Records moves up to 3rd and is owed another $100
Sean Richardson moves up to 4th and is owed $50
Kent Wiseman moves up to 5th and is owed $100

Checking my math...the above adds up to $600, which is what John will be submitting forms for; 3rd in R1 and 2nd in R2.

[BryanL]

Ok-I'll be the one to ask what everyone else would want to know. How much power did his little 302 make? Kudos to all involved in being a good sport to seal the hood and get an official dyno. Sorry you went over John.

[martinsntx]

Ok-I'll be the one to ask what everyone else would want to know. How much power did his little 302 make? Kudos to all involved in being a good sport to seal the hood and get an official dyno. Sorry you went over John.

272hp and 302trq, with my post race weight I was 5hp over. I'm now restricted down to 263hp and 296trq. Still better torque then I've ever had, so I'm happy with that. Not so much about blowing the dyno. I'm sorry for causing the group any trouble but will do my best to make it right.

John

[BADVENM]

Something I've been thinking about and since its rules change request I guess I'll throw it out there:

Has there been any thought of sealing access to the fuel tank at the end of the weekend as well as the hood? Its possible that someone whos hood is sealed could go home
and add fuel into the tank increasing their weight and offsetting the overage of hp and/or tq when the car is dynod.

I'm not after anyone in particular, just thinking out loud as we had a Rocky Mountain CMC racer in a similar situation. I know we cant remove all of the what ifs but this seems like a pretty
easy thing to do and would remove an easy opportunity to boost the weight to meet the hp/tq rules.

Thoughts?

Regarding our little 302 (now 308) Mustang engine, three years ago I dynod and got my numbers right where I wanted them to not have to add additional weight. No changes were made over the winter and prior to the next season starting I dynod like 10hp and 10-15tq over whats allowed. Strange how the numbers can change with zero adjustments being made from one season to the next.

Dave

[ShadowBolt]

Great idea Dave.

On the engine making more power at a later date....how much of that is because an engine gets broken in, loosens up or the rings seat completely? No issues with too much power running the 4.6.


JJ

[BADVENM]

Thoughts on sealing the computer as well? I think Dustin had mentioned the idea to me when also sealing the hood.

Sorry this is getting off topic, I can start another thread or do a rule change request if y'all think its got some legs to stand on.

[Rob Liebbe]

Has there been any thought of sealing access to the fuel tank at the end of the weekend as well as the hood? Its possible that someone whos hood is sealed could go home
and add fuel into the tank increasing their weight and offsetting the overage of hp and/or tq when the car is dynod.



The only "official" scale is the one at the track when you go to tech after a race. Adding fuel to increase weight at the dyno time should not be a relevant factor.

[Al Fernandez]

That's correct Rob. We weigh the car at the track post race, not at the dyno later. Had it been a fuel injected car we would also have sealed the computer and OBDII ports. I should've said right at the onset that John was great throughout. Sorry you couldn't keep those results John.

[BryanL]

272hp and 302trq, with my post race weight I was 5hp over. I'm now restricted down to 263hp and 296trq. Still better torque then I've ever had, so I'm happy with that. Not so much about blowing the dyno. I'm sorry for causing the group any trouble but will do my best to make it right.

John

Thanks John. Great example of a gentleman and a gentleman racer making things right and fair. This is the kind of people I enjoy racing and hanging out with at the track.

Good questions Dave. Is your 302 carb or FI? Same dyno? Have you checked another dyno? What was the weather difference between the two dyno days? Apparently the further you get away from the SAE corrected weather readings the less accurate the correction factor. We experienced this in Houston one year dynoing on a very cold day-I had to go to smaller plates that cut about 15-20 hp off when I went back to another dyno and others had a similar experience. Of course with a carb the numbers could fluctuate pretty good based on weather I think, too.

[mach1]

Thanks John. Great example of a gentleman and a gentleman racer making things right and fair. This is the kind of people I enjoy racing and hanging out with at the track.

Totally, John was very upfront about it right from the start of the weekend. I would be worried about running a carb and inconsistent numbers. My EFI car has been on 3 different dynos (all in DFW though) and run with 4 different motors and always been within 5hp.

[Supercharged111]

Dave's car is EFI and hits the same dyno every year. That dyno is very consistent too. Most cars here pump out the same numbers year after year. Ken's car was one of those until this year when it decided to make an extra 20 some hp.

[Trublu]

Totally, John was very upfront about it right from the start of the weekend. I would be worried about running a carb and inconsistent numbers. My EFI car has been on 3 different dynos (all in DFW though) and run with 4 different motors and always been within 5hp.

Good point Tyler. I agree. What we need is a 7hp carb allowance on Dyno checks.

[mach1]

Good point Tyler. I agree. What we need is a 7hp carb allowance on Dyno checks.

Agreed!

[Fbody383]

Agreed! Look, that's two for AIX... no more dyno issues. (says the guy who can't read a tape measure or a scale. we'll put about 75lbs more in the 15 before we get to TWS)

[Al Fernandez]

You already have a 7hp allowance...target power is 260 :)

[BryanL]

You already have a 7hp allowance...target power is 260 :)

Wrong. That maybe your target but not the target for certain cars/tracks. That was proven out in Cali on the high speed tracks that it's better to run the higher hp numbers-now it's even more skewed with the weight breaks. Change up the weight breakdown so it's not an advantage to run over 260 and maybe then you would have 260 as a target. The Fox can run 7 more hp than an LS car and still weigh 100 pounds less. I think we have seen what 7 more hp can do on some straights.

This makes me curious about the carb guys. Do you guys have to have multiple dyno runs with different jets? Or do you run the same jets all season?

[martinsntx]

This makes me curious about the carb guys. Do you guys have to have multiple dyno runs with different jets? Or do you run the same jets all season?

The rules state that a carb car can change jets to facilitate tuning. I take this to mean that I can change jets when necessary to maintain a consistent air to fuel ratio. Before a dyno? I don't have that answer.

7.21.1 The jets, metering rods, needles, etc in the stock / spec carburetor may be changed to facilitate
tuning.

I typically only change jets for altitude changes. With a single jet size I see 12 -13 A/F from Dallas to NOLA. But Hallett and Colorado are very different jet sizes to maintain that A/F ratio.

[Supercharged111]

Wrong. That maybe your target but not the target for certain cars/tracks. That was proven out in Cali on the high speed tracks that it's better to run the higher hp numbers-now it's even more skewed with the weight breaks. Change up the weight breakdown so it's not an advantage to run over 260 and maybe then you would have 260 as a target. The Fox can run 7 more hp than an LS car and still weigh 100 pounds less. I think we have seen what 7 more hp can do on some straights.

This makes me curious about the carb guys. Do you guys have to have multiple dyno runs with different jets? Or do you run the same jets all season?

Foxes run 150# lighter, SN95/Edge can run up to 100# lighter.

[Trublu]

Foxes run 150# lighter, SN95/Edge can run up to 100# lighter.

More correct to say foxes are able to run 150# under. In my case my racing snake physique puts the 65 fox 70# over on the scales.

[michaelmosty]

Wrong. That maybe your target but not the target for certain cars/tracks. That was proven out in Cali on the high speed tracks that it's better to run the higher hp numbers-now it's even more skewed with the weight breaks. Change up the weight breakdown so it's not an advantage to run over 260 and maybe then you would have 260 as a target. The Fox can run 7 more hp than an LS car and still weigh 100 pounds less. I think we have seen what 7 more hp can do on some straights.

This makes me curious about the carb guys. Do you guys have to have multiple dyno runs with different jets? Or do you run the same jets all season?

Anyone is welcome to have multiple dyno's for various setups. Ex, you can have a 260 hp dyno for certain tracks and a 265 hp dyno for different tracks.

Any change to carb jets will require a new dyno. The dyno form has a spot for jet sizes so if tech is performed, the jets in the carb must match the jet size on the submitted dyno.
I have had many recommendations for more tech items confirming ignition timing, fuel pressure, etc. This would be something that falls into a similar category.

[mach1]

The issue I would have running a carb is when the weather changes so does the mixture since there is nothing to compensate. If I dyno and get a 12:1 AFR, weather changes, and it pushed me to 13:1, I would be over power.

Michael, how do you feel about out of region (CO) guys running with us, considering they are hitting the dyno at 5000ft. When BCurtis was at MSRC last year, his car was very strong, I'd say he was 10hp over based on how he pulled, I think he even switched to a smaller restrictor too.

[RichardP]

Anyone is welcome to have multiple dyno's for various setups. Ex, you can have a 260 hp dyno for certain tracks and a 265 hp dyno for different tracks.

Any change to carb jets will require a new dyno. The dyno form has a spot for jet sizes so if tech is performed, the jets in the carb must match the jet size on the submitted dyno.
I have had many recommendations for more tech items confirming ignition timing, fuel pressure, etc. This would be something that falls into a similar category.


I agree that's what the rules say but that's not what's happening. It's a break in the rules and also technically wrong, in my opinion. You can dyno your car at sea level in Houston with the range of jet sizes that you are planning on running for all of the different tracks you are planning on running for the season. When the car is running at sea level using the higher altitude jet sizes, it's not going to be representative of what the car will do at altitude. It's actually more honest to change your jets at the track to get your car running the same at altitude as it did at sea level even though that is technically illegal.

The computer cars are certainly altering their parameters to match current running conditions. The carbed cars need to do that too.


Richard P.

[Pranav]

In other news, they recently closed the observation deck on the 60th floor of the Chase tower downtown.

What they didn't tell you is they opened a dyno shop in place of it.

I have begun brokering secret NASA dyno certs for all Texas and Louisiana racers at this elevated altitude.

Bring cash, leave with the most competitive dyno this side of the Rockies...

[BADVENM]

At the west coast nationals Laguna Seca last year we dynod the Pumpkin to ensure we fit the thresholds of PTB (there isn't CMC out west). As you know they are very close to sea level. We were within 1hp and 1-2tq of our dyno sheet from the beginning of the same season at MAC Autosports (only place we've ever dynod at for CMC) which as you mention is at least a mile high elevation. We were quite impressed how close we were given the degree of elevation change.

I read a little bit regarding the dyno woes at Watkins Glen this year. Anyone have similar stories of dynos out there following previous years trends of being way over on hp and tq compared to the ones we use regionally?

[Fbody383]

"racing snake physique"

Yella Terra has hereby been replaced... can't wait to see the new logo.

[BryanL]

Yella Terra has hereby been replaced... can't wait to see the new logo.

Too many Shrimp on the Barbie and Miller Lites!

[Trublu]

I agree that's what the rules say but that's not what's happening. It's a break in the rules and also technically wrong, in my opinion. You can dyno your car at sea level in Houston with the range of jet sizes that you are planning on running for all of the different tracks you are planning on running for the season. When the car is running at sea level using the higher altitude jet sizes, it's not going to be representative of what the car will do at altitude. It's actually more honest to change your jets at the track to get your car running the same at altitude as it did at sea level even though that is technically illegal.

The computer cars are certainly altering their parameters to match current running conditions. The carbed cars need to do that too.


Richard P.

Get a grip guys. Changing jets to maintain AF as conditions change is exactly the same as what your EFI computer is doing in real time. I think worth educating before introducing something that would require dozens of Dyno hours to produce.

[Storm Trooper]

I agree. A fuel injector is an adjustable Jet that your computer controls.

[Al Fernandez]

Dynojet modifies the measured output to reference conditions which include atmospheric pressure (that's the SAE J349 setting on the machine) but the accuracy of this correction decreases as elevation increases.

It's entirely possible we need to change what the book says re jets and rods, kinda how we ended up changing the requirements for carb cars around fuel pressure.

[Supercharged111]

The issue I would have running a carb is when the weather changes so does the mixture since there is nothing to compensate. If I dyno and get a 12:1 AFR, weather changes, and it pushed me to 13:1, I would be over power.

Michael, how do you feel about out of region (CO) guys running with us, considering they are hitting the dyno at 5000ft. When BCurtis was at MSRC last year, his car was very strong, I'd say he was 10hp over based on how he pulled, I think he even switched to a smaller restrictor too.

I hit the dyno at 6200', but that dyno puts out the same numbers as Mac's (5XXX'). I'm the 2nd one to confirm that, so I feel good about using it. Come to think of it, Randy's car made the same numbers with the same plate as it did back in TX. When John and Sean came to Pueblo last year, John was able to shut down a run I got on him on the front straight, so I figured they weren't being cheated. This year with the Ken incident I know Craig and Mike were feeling cheated, but what I don't know is if they felt everyone was pulling on them or just Ken.