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JS154
06-03-2013, 08:03 PM
<snipped>

-=eh

Greg Amy
06-03-2013, 08:42 PM
Eric, didn't you have the pole, led flag-to-flag, and then the win on Saturday before you got wrecked out on Sunday...? In your non-turbo BMW E30?

- GA

Saturday Results
(http://www.scca.com/assets/results/13_moh_grp1%20sat%20race%20final%20results.pdf)
(http://www.scca.com/assets/results/13_moh_grp2%20sunday%20final%20race.pdf)Sunday Results (http://www.scca.com/assets/results/13_moh_grp1%20sunday%20final%20race.pdf)

Z3_GoCar
06-03-2013, 09:22 PM
Sorry Greg,

I don't understand how SRF results are pertinent....

Eric was T-boned on the pace lap of Sunday's race and was DNS.

I think his point is that even with the tire and TIR changes we're looking at a repeat of last years Runoffs results.

benspeed
06-03-2013, 09:42 PM
Greg fat fingered the link - times looked comparable...

That so blows- wrecked on the pace lap??? How

Z3_GoCar
06-03-2013, 09:54 PM
According to his Facebook post, the pace car bunched the field up, to slow the start down. He says it cracked the welds on the x-bar, and maxed his g-meter out at 5.6g latteral.

Greg Amy
06-03-2013, 10:29 PM
I don't understand how SRF results are pertinent....
Corrected.


Greg fat fingered the link - times looked comparable...
0.7s fast lap difference across the weekend.

lawtonglenn
06-03-2013, 11:45 PM
Eric, didn't you have the pole, led flag-to-flag, and then the win on Saturday before you got wrecked out on Sunday...? In your non-turbo BMW E30?




Eric I don't see the data behind your argument... it seems as if you are saying
that the turbo Solstices should be slowed down because they have some possibility of catching you?

:shrug:

Is there some way you can build a bridge for me from Saturday's race data
to your conclusion? Because I don't see it.

.

JS154
06-04-2013, 08:08 AM
As a committee member nI should have put more thought into it before posting the letter I sent to the CRB to a public forum, so i am taking it down.

benspeed
06-06-2013, 08:34 AM
Eric - no worries about the letter. While the data from the Ohio race didn't back up your argument I tend to agree that STU is going to be a turbo class. The turbos walked the field at the Runoffs and I think will smoke the field at any big fast tracks like WGI.

I know I'd put. 944 2.5 turbo in the 968 if I was capable of funding an STU car.

Z3_GoCar
09-22-2013, 11:28 PM
FI's still smoking the field... any plans to address this for next year? Laguna Seca may be a smaller track, but all the major straights are up hill, and some are pretty steep, so power to weight imballances will show up in a big way.

Maybe I should be asking, if STU is even going to be around next season. With only seven cars at the run-offs it seems doomed just like STO was two years ago.

Knestis
09-23-2013, 06:57 PM
FI's still smoking the field... any plans to address this for next year? Laguna Seca may be a smaller track, but all the major straights are up hill, and some are pretty steep, so power to weight imballances will show up in a big way.

Maybe I should be asking, if STU is even going to be around next season. With only seven cars at the run-offs it seems doomed just like STO was two years ago.

FWIW, a slightly informed opinion having watched pretty carefully - and participated - for a season...

STU's challenge is NOT the turbos. It's the fact that it's STU, with all that the rule set proposes in terms of budget required to run a pointy-end effort.

I know the effort we've put into this year and have some idea what would be required to do it right - particularly in terms of braking and getting down to weight. An NA car COULD be competitive but it would take cubic dollars to make it happen. Right now, given the state-of-art and spending in the class, the returns on a forced induction engine are better at, say, 90% of an "all in" budget than for an unblown engine at the same level of spending...

...and at some point, diminishing returns means that (1) $1000 improves lap times less than it did earlier in the R&D process, and (2) the gains are made in areas other than the engine - gear ratios, for example - because those low-hanging turbo fruit have been picked. What kind of gear clusters are those uncompetitive NA cars running? Have they taken full advantage of brake system allowances? Etc.

The rules for ST - much like IT - have got to be made presuming that eventually someone will do a 100% version of every option, and "equity" among those options has to be estimated at that build level. Right now, a less-than-full-tilt build can make more horsepower, so a BIGGER DIFFERENCE, with a turbo than can be made with an atmospheric engine for the same dough.

I'd argue that accounts for a lot of the "overdog" anecdotal observations.

K

Z3_GoCar
09-23-2013, 08:40 PM
FWIW, a slightly informed opinion having watched pretty carefully - and participated - for a season...

STU's challenge is NOT the turbos. It's the fact that it's STU, with all that the rule set proposes in terms of budget required to run a pointy-end effort.

I know the effort we've put into this year and have some idea what would be required to do it right - particularly in terms of braking and getting down to weight. An NA car COULD be competitive but it would take cubic dollars to make it happen. Right now, given the state-of-art and spending in the class, the returns on a forced induction engine are better at, say, 90% of an "all in" budget than for an unblown engine at the same level of spending...

...and at some point, diminishing returns means that (1) $1000 improves lap times less than it did earlier in the R&D process, and (2) the gains are made in areas other than the engine - gear ratios, for example - because those low-hanging turbo fruit have been picked. What kind of gear clusters are those uncompetitive NA cars running? Have they taken full advantage of brake system allowances? Etc.

The rules for ST - much like IT - have got to be made presuming that eventually someone will do a 100% version of every option, and "equity" among those options has to be estimated at that build level. Right now, a less-than-full-tilt build can make more horsepower, so a BIGGER DIFFERENCE, with a turbo than can be made with an atmospheric engine for the same dough.

I'd argue that accounts for a lot of the "overdog" anecdotal observations.

K

Sorry Kirrk, it's a matter of can't make a 2750lb/310 flywheel hp car compete with a 2500lb/300whp turbo/FI car. The power to weight numbers still just don't work out for N/A at this point even with a total wheel men behind the wheel. Eric's 4th and Andrew Cadell's 7th are the best we can do at this point, and Andrew's ride was prepared by VAC, then there's Irish Mike's World Challenge e-46. All were multi seconds behind any of the first three.

Knestis
09-25-2013, 09:37 PM
Are you making the argument based on power/weight or on Runoffs results...?

The difference between 8.87 lb/hp and 8.33 lb/hp simply doesn't guarantee a win irrespective of other variables that influence lap times. No way.

K

Z3_GoCar
09-26-2013, 12:22 AM
Are you making the argument based on power/weight or on Runoffs results...?

The difference between 8.87 lb/hp and 8.33 lb/hp simply doesn't guarantee a win irrespective of other variables that influence lap times. No way.

K

Ah, but my arguement is that there's no way that a 2750lb/310 flywheel hp -> 2750lb/256 whp -> 10.7 lbs/hp has a chance aginst a 8.33 lb/hp car... unless the driver in the 8.33 lb/hp car is suffering from CO poisining.

I'm saying the finshing order at the run offs is direcly predicted by the hp/weight of the cars. 1st/2nd were in the 8.3 range 3rd was at the 9.7 range and 7th was in the 10.5 range. That is a disparity that's not being addressed to date, and will only be made worse at Mazda Raceway Laguna Seca by all the up-hill straights.

Knestis
09-26-2013, 05:31 AM
At which point you're making comparisons between examples using a mix of "flywheel hp" and "whp," using what I presume are "known" values - and I tune out as quickly as I do when people start playing math games with driveline loss and dyno rumors in IT. :)

K

Z3_GoCar
09-26-2013, 11:03 PM
I am building an all out engine, and so have several others. I know that the VAC car that finished 7th was with an all out built motor and chassis. Irish Mike was using his acutal World Challenge car. So, your insinuation that there are no fully built N/A cars is patently false. It's also false that a turbo car would be any less expensive build than a N/A build, it requires an additonal highly engineered part that stresses all other parts around it.

Rabbit07
09-27-2013, 08:14 AM
My observations of the Result of the RunOfFs are that the only car that really needs an adjustment is the Lotus. There wasn't a single Turbo car there other than the one found to be non compliant that went any faster than the NA cars.

Knestis
09-27-2013, 10:43 AM
I am building an all out engine, and so have several others. I know that the VAC car that finished 7th was with an all out built motor and chassis. Irish Mike was using his acutal World Challenge car. So, your insinuation that there are no fully built N/A cars is patently false. It's also false that a turbo car would be any less expensive build than a N/A build, it requires an additonal highly engineered part that stresses all other parts around it.

I didn't say either of those things.

I said that it's easier to get more bang for the first 90% of spending (against a theoretical all-in build) with a turbo than it is with an NA engine, and I stand by that assertion.

As to particular examples, I have exactly ZERO knowledge of what Flynn or anyone else spent on their engines. Whether it's his "actual" WC car (or not) has no bearing.

My general complaint is that this argument focuses on only one factor - and a binary one at that. Whether a car has a turbo (so code that"1" in the data) or no turbo (code it "0") simply is NOT a good predictor of lap times, in and of itself without considering other variables.

How about roof height for starters...? My PERSONAL druthers are that "Touring" cars should be defined by interior volume, before other factors get dealt with, to make sure that they are all starting on a more even platform. Lots of other variables (e.g., weight reduction potential, frontal area, parasitic drag, add-on wing efficiency, CoG, etc., etc.) are built on that foundation and "Lotus" and "Miata" don't seem consistent with first-principle understandings of what a Touring Car is (see also, "Grand Touring").

K

Rabbit07
09-27-2013, 11:05 AM
K, I am with you brother. Cars such as the Miata, Solstice, Lotus really have no place in touring car racing. I noticed this when I first became aware of the class. I even had mentioned it to rules makers, but was dismissed. No surprise to me that cars such as this have an advantage regardless of them being boosted or not.

Greg Amy
09-27-2013, 11:08 AM
Amen.

Dano77
09-27-2013, 11:49 AM
I was always told a Tourng Car needed to have a back seat. These cars you speak of have no back seat. Certain exceptions have been made in the past, like the RX7 with the GI Joe sized rear seats.

Th Lotus and Miata punch a VERY small hole in the air. An Intgra or Jetta a Very Large hole.

Just sayin...

Andy Bettencourt
09-27-2013, 01:30 PM
Observations:



If it's really a Touring class then the 2 seaters need to go - but its not and never was
Every single 'T' class in the SCCA has 2 seaters. STO, STU and STL. 4 seats was never part of the concept, 'Touring' was just a name when envisioning a place for ex-WCTC to land in SCCA amateur racing and giving other cars a chance to be built to those specs. It's right in the Purpose statement in the GCR
Solo breaks their 'Street Touring' up every which way from Sunday - in a way I can't quite figure out but for sure RWD/FWD and 2 seats and 4+
Using wet conditions for a 'look' at results is a tough call
Forced induction is a freaking NIGHTMARE to get right. Even in Pro racing they can't get it right the first few years. It takes a mandatory $12K dollar Bosch ECU now so they can monitor every single output to get close

It's a great set of classes and STL is still ramping up. I really enjoyed seeing more FWD cars out there because of the creativity you can apply when building them. I still wish you could use any year chassis and modern powerplants. Maybe even total Frankenstein cars like an ITS-chassis 924/944 with a K20.


I thought about picking up a GA-spec ST RX-8, tune it a bit and do some Nationals but then realized Laguna was next. I think the cars with the best blend of power and handling with be the cars to beat until it hits Daytona...


Good stuff.

JS154
09-30-2013, 09:56 PM
My observations of the Result of the RunOfFs are that the only car that really needs an adjustment is the Lotus. There wasn't a single Turbo car there other than the one found to be non compliant that went any faster than the NA cars.

Non-compliant, that sounds so nice.

I have a stronger opinion that I will keep to myself for now.

Chris is pretty right, except for one angle I think is "small FI cars" need to be adjusted. The rest of them were on par with where we expected them to be.

The Audi we knew was going to be a threat if it rained. It did.

Irish Mike and I were on par with where we were the last couple of years. The VAc car was a full build, but not fully sorted. Mike's car is built and sorted, and mine is built and (now) sorted too.

JS154
09-30-2013, 09:58 PM
Observations:



If it's really a Touring class then the 2 seaters need to go - but its not and never was
Every single 'T' class in the SCCA has 2 seaters. STO, STU and STL. 4 seats was never part of the concept, 'Touring' was just a name when envisioning a place for ex-WCTC to land in SCCA amateur racing and giving other cars a chance to be built to those specs. It's right in the Purpose statement in the GCR
Solo breaks their 'Street Touring' up every which way from Sunday - in a way I can't quite figure out but for sure RWD/FWD and 2 seats and 4+
Using wet conditions for a 'look' at results is a tough call
Forced induction is a freaking NIGHTMARE to get right. Even in Pro racing they can't get it right the first few years. It takes a mandatory $12K dollar Bosch ECU now so they can monitor every single output to get close

It's a great set of classes and STL is still ramping up. I really enjoyed seeing more FWD cars out there because of the creativity you can apply when building them. I still wish you could use any year chassis and modern powerplants. Maybe even total Frankenstein cars like an ITS-chassis 924/944 with a K20.


I thought about picking up a GA-spec ST RX-8, tune it a bit and do some Nationals but then realized Laguna was next. I think the cars with the best blend of power and handling with be the cars to beat until it hits Daytona...


Good stuff.

It's not a Touring class - it has nothing to do with Street Touring. It really is Super Touring - wI doubt anyone is going to pick a bone over a rear seat or 2+2er or no rear seat when we need cars and entries. Aside from all that what it really comes down to is it is an engine class.

Andy Bettencourt
09-30-2013, 11:33 PM
It's not a Touring class - it has nothing to do with Street Touring. It really is Super Touring - wI doubt anyone is going to pick a bone over a rear seat or 2+2er or no rear seat when we need cars and entries. Aside from all that what it really comes down to is it is an engine class.

Correct, but people are getting hung up on the 'Touring' part of then name...when that was all it was at the time of conception - just a name, not a concept.

Knestis
10-01-2013, 07:15 AM
...except that if it is an "engine" class - which it is - any given drivetrain option is going to be more competitive in a 2-seat platform than it will in a 4-seat platform. That kind of makes it a "chassis" class.

Anyone doing a purpose-built STU car today would be wise to keep that in mind.

K

PS - Congratulations again on your successes this year, Eric. It was nice having you and Irish Mike as yardsticks at the Majors we ran with the TDI.

Greg Amy
10-01-2013, 08:21 AM
...except that if it is an "engine" class - which it is - any given drivetrain option is going to be more competitive in a 2-seat platform than it will in a 4-seat platform. That kind of makes it a "chassis" class.
Bingo.

There's no discussion on this within the STAC; we're simply talking amongst us girls here. But it brings up a very good point that I'd not directly considered (or realized). It's also an issue that orgs try to address inferentially via the RWD adders. Unfortunately, if we continue to address this inferentially (say, try to equalize the S2000 chassis with the Integra using same K20 engine), then as a result any comparable non-2-seater is going to be placed at a significant disadvantage. But that's the direction we're going.

I envision absolutely no support within the Club to have separate adders for 2- and 4-seaters, and without explicit spec lines I see no way within the existing STCS to adequately express that regulation without potential conflict and disagreement (e.g., is the RX-8 a 2- or 4-seater? What about the 911? Would we have to implement The Cleveland Test, as in "I'd ride back there all the way to Cleveland"? Who gets to decide that?).

- GA

Andy Bettencourt
10-01-2013, 08:37 AM
I would agree it's a chassis class. But I would also submit that it has little to nothing to do with the amount of seats. I don't see many people jumping to build Ford EXP's, Fiero's, Mercury Capri's or any other 2-seater on a shit platform.

The Lotus, Miata and RX-8 all have one thing in common - great suspension design. Is that 'typical' of cars with 2 seats? Maybe more so than 4 seats but there are plenty of 4-seat sporty cars...and plenty of 2 seat turds. If you want to regulate something, regulate suspension design.

As with any racing class, you need to look at suspension design and potential for power. Pick the weapon that combines your perception of the best combination of attributes.

Z3_GoCar
10-01-2013, 09:29 AM
...except that if it is an "engine" class - which it is - any given drivetrain option is going to be more competitive in a 2-seat platform than it will in a 4-seat platform. That kind of makes it a "chassis" class.

Anyone doing a purpose-built STU car today would be wise to keep that in mind.

K

PS - Congratulations again on your successes this year, Eric. It was nice having you and Irish Mike as yardsticks at the Majors we ran with the TDI.

That's not neccessarily true. The Z4 has the exact suspension as Irsh Mike's car and yet Mike's car has less drag, even if the Z4 had its factory hard top on. The reason for the difference is under the car, a full factory undertray. This is missing from the Z-series cars. Size doesn't predict aerodynamic efficiency. Notice the dearth of Z series racers in North America, only in Europe can a significant number of Z-series race cars be found.

Kirk, ask Breault why he switched from a Z3 to a sedan/coupe. They've got better aero, and are less twitchy while the drive train are exactly the same.

All I'm looking for is parity in the lbs/hp area. I just don't see it not with the potential of both fully built N/A and F/I side by side. I just want to be in the ball park with a fully built motor/car, not out on the parking lot or the street please.

Thanks,

ps. Eric, I haven't seen anything about any of the finishers in STU getting DQ'ed. Can you fill me in with any more information?

Greg Amy
10-01-2013, 10:05 AM
...ask Breault why he switched from a Z3 to a sedan/coupe.
I think he switched because he was frustrated that the rear suspension on the Z3 kinda really sucks, right? The 328 is just a better car overall. And he got a killer deal on it, already developed, instead of continuing with development on the Z3.


I haven't seen anything about any of the finishers in STU getting DQ'ed. Can you fill me in with any more information?Mark Hoover was DQ'd due to a non-compliant turbo inlet restrictor. I do not know the exact details, but hearsay has it that it did not maintain the 3mm distance as required by the GCR Technical Glossary definition:


Turbo Inlet Restrictor – A system to limit engine performance that meets these criteria. The inlet restrictor shall have a single, circular opening through which all inlet air passes. The maximum ID of the restrictor is listed on the vehicle’s spec line. The restrictor’s maximum ID must be maintained for at least 3 mm. This 3 mm restrictor segment shall be placed within 50 mm of the rotating section (impeller assembly) of the pressurizing unit. On engines where the approved turbo prohibits meeting this distance, different locations may be approved by the CRB on a case by case basis. If an alternative location is approved, the entire restrictor assembly shall have a maximum length of 50 mm. There shall be no other provisions for airflow to the turbocharger other than through this single orifice.I'm guessing we'll see something in the Appeals Court section of Fastrack, assuming it got that far.

- GA

Andy Bettencourt
10-01-2013, 12:46 PM
I think he switched because he was frustrated that the rear suspension on the Z3 kinda really sucks, right? The 328 is just a better car overall. And he got a killer deal on it, already developed, instead of continuing with development on the Z3.


If we are talking about Rob he not only abandoned the Z3 chassis but the Z3 in ITA. He built the E36 from scratch from a 328.

Z3_GoCar
10-01-2013, 02:39 PM
I think he switched because he was frustrated that the rear suspension on the Z3 kinda really sucks, right? The 328 is just a better car overall. And he got a killer deal on it, already developed, instead of continuing with development on the Z3.

Mark Hoover was DQ'd due to a non-compliant turbo inlet restrictor. I do not know the exact details, but hearsay has it that it did not maintain the 3mm distance as required by the GCR Technical Glossary definition:

I'm guessing we'll see something in the Appeals Court section of Fastrack, assuming it got that far.

- GA

The arms on the rear are litterally off of an e-30, and Eric seems to be making that work. Might have to do with the Chapman principal: if movement causes non ideal goemetry stop the movement.