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26 minutes ago, Black Magic said:

 

Assuming we get your swap weight to be a reasonable value for the car (not a convertible).... you played by the rules that put a exponential penalty for adding power beyond a certain point when swapping an engine. Shouldn't it be reasonable another guy pays the same penalty for making that power (or alot more) in another method? 

 

Otherwise you should have found a low HP 5.0 and cammed\ported the head to circumvent the intended pwr of the series for your car and kicked more butt......

what **exactly** is the series specified P/W ceiling #? Can you point me to where this lives in the rules? This specifically is the root cause issue for the GBU problem. There is no formal limit on PW, and if there was you'd go a long way towards mitigating the other distortions in the rule set that make all this so messy and unattractive from a participation perspective.

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Good morning folks.  I had a great discussion with Mike Chisek and Bill Riley yesterday.  I knew that the TAC was working on about 5 or 6 additional cars that need revalued on the VPI list so for 2021

My story.  I'm not one for protesting.  Have never done it. I also understand that post race tech, whether protested by a team or discovered by tech, illegal is illegal.  When I am asked to withdraw m

Just to be clear.  Nobody is upset with GBU for building the car or how the team is or drives.  We are upset with how the series handled teching and point association with this car, both pre and post

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18 minutes ago, atxe30 said:

what **exactly** is the series specified P/W ceiling #? Can you point me to where this lives in the rules? This specifically is the root cause issue for the GBU problem. There is no formal limit on PW, and if there was you'd go a long way towards mitigating the other distortions in the rule set that make all this so messy and unattractive from a participation perspective.

 

It lives within the swap calculator, the forum search will show the math behind it and the theory when it was built.

 

Short answer.... in terms of estimated race weight to estimated crank hp....The 2797 "swap weight" rx7 just crosses the threshold at 200 hp (becomes more than 50 points swap cost). 2797 lbs /200 hp = 13.99 lbs \hp.  

 

In a practical sense you will need to be 12:1 to compete for the overall (crank not wheel hp to raced weight, full fuel). When the swap calc limit was set the 500 point car power limits were a bit closer to 13:1, weights were picked from the heaviest car to sort of get the practical limits back to 12-13 for the "legacy" cars. 

 

Engine mods were much more expensive in the past, VPI's were higher so fewer cars blew the as raced PWR apart. There was never real control over the effect of engine mods in terms of targeting a PWR, just fewer teams played in this area when it was a cheaper series. 

 

Long ago before swap rules, the "SX400" blew the PWR apart and created the swap calc with its non linear points applied after 14:1. Maybe GBU will finally force the same thing in regards to engine mods, swap weights and VPI (VPI already has started these corrections) 

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59 minutes ago, Black Magic said:

 

Exactly the point, for engines with significant engine mods that respond well to those mods you are capable of adding significantly more power than the series is targeting (or perhaps the points would indicate). 

 

VPI is set on the performance of the stock engine. We generally, or at least used to have limits of power to weight that were allowed in 500 and under point cars. The swap calculator also has a targeted limit of power to weight. The only way you get radical departures from the series target power to weight is from engine mods for points (heads, cams and forced induction the main players), silly swap weights and lobbying for low vpi on an otherwise powerful car. 

 

The concept is that for ALL cars ALL engine mods would have to go through a calculator where you enter base power and click check boxes for the engine mods you did. It multiplies the base power by factors for each engine mod and assigns points in a non linear function using the same math as the swap calculator. That way you put increasing penalty for mods that should result in big departures from the series rough intention of power to weight. 

 

Anyone really think the performance of GBU swapping in a newer rear diff and axles equals that of running a bigger cam (50 points)? 

Don't hate on old school American Iron. Wait until they start winning consistently. LOL. I just did the math. If we went with a cell +2 gallons, we'd get an additional 12 minutes. Not sure that's worth the cost. 

 

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Here's an unpopular idea:

 

No minimum pit time at all, which would have a couple of descending effects. 

Since the driver can be changed during fueling, the driver and fuel usually take about the same time. There are some cars that fuel very fast but the driver change is still finished before fueling. Also, the car cannot be worked on during fueling, so changing tires would penalize a team a minute or two to do so. Say the fuel and driver takes 2min, and tires takes another 2min (easy numbers).

 

Normal stops would take 2min ish, but an extra 2min would be added if tires got changed. 

 

Not to mention the whole host of effects the "splash and go" could have, that the balance of cars and their tank sizes would be less important. 

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21 minutes ago, TiredBirds said:

Don't hate on old school American Iron. Wait until they start winning consistently. LOL. I just did the math. If we went with a cell +2 gallons, we'd get an additional 12 minutes. Not sure that's worth the cost. 

 

 

There are actually alot of non V8, no iron headed motors with a heavily decammed engine option for heavier cars. Often double whammy, higher displacement and lower power. Imagine a 140 hp version of a 200 hp engine ported and with a cam swapped into a car for 100 points total that makes 200 hp. Imagine that in a car that should be paying 300 points or more in the swap calc if it had 200 hp..... 

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4 minutes ago, Black Magic said:

 

There are actually alot of non V8, no iron headed motors with a heavily decammed engine option for heavier cars. Often double whammy, higher displacement and lower power. Imagine a 140 hp version of a 200 hp engine ported and with a cam swapped into a car for 100 points total that makes 200 hp. Imagine that in a car that should be paying 300 points or more in the swap calc if it had 200 hp..... 

I just don't think it is logistically possible  to get a real HP/weight formula on every car. 

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7 minutes ago, TiredBirds said:

I just don't think it is logistically possible  to get a real HP/weight formula on every car. 

 

Same hp weight formula applied to all cars.

 

Just like the swap calc already does.

 

Sample Model

 

Heads                                .25

Cam                                   .2

Intake                                 .1

Carb\Throttle Body           .1

Header                               .1

 

You add up your multipliers. So a motor with heads, cam, intake, header is .25 + .2 + .1 + .1, or .65

 

You take your engine's base power, and add .65 * it. So if you have a smog era 200 hp engine it is now 200 + 200*.65 = 330 hp 

 

That 330 hp gets dumped right into the swap calc function. Points assigned. 

 

If your car is a land yacht, 330 hp might be an ok power to weight. You may pay only 100 points. If your car is a vette this would be 2000+ points. Under current rules, you could do this with the vette for well under 500. 

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18 minutes ago, TiredBirds said:

I just don't think it is logistically possible  to get a real HP/weight formula on every car. 

 

I think limiting swaps to bolt on changes is the only real fix.  

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18 minutes ago, Black Magic said:

 

Same hp weight formula applied to all cars.

 

Just like the swap calc already does.

 

Sample Model

 

Heads                                .25

Cam                                   .2

Intake                                 .1

Carb\Throttle Body           .1

Header                               .1

 

You add up your multipliers. So a motor with heads, cam, intake, header is .25 + .2 + .1 + .1, or .65

 

You take your engine's base power, and add .65 * it. So if you have a smog era 200 hp engine it is now 200 + 200*.65 = 330 hp 

 

That 330 hp gets dumped right into the swap calc function. Points assigned. 

 

If your car is a land yacht, 330 hp might be an ok power to weight. You may pay only 100 points. If your car is a vette this would be 2000+ points. Under current rules, you could do this with the vette for well under 500. 

??? so our 305 (base 215hp) would be 322.5? (cam, intake, carb, headers)? Not sure we are there. 

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37 minutes ago, Black Magic said:

 

Same hp weight formula applied to all cars.

 

Just like the swap calc already does.

 

Sample Model

 

Heads                                .25

Cam                                   .2

Intake                                 .1

Carb\Throttle Body           .1

Header                               .1

 

You add up your multipliers. So a motor with heads, cam, intake, header is .25 + .2 + .1 + .1, or .65

 

You take your engine's base power, and add .65 * it. So if you have a smog era 200 hp engine it is now 200 + 200*.65 = 330 hp 

 

That 330 hp gets dumped right into the swap calc function. Points assigned. 

 

If your car is a land yacht, 330 hp might be an ok power to weight. You may pay only 100 points. If your car is a vette this would be 2000+ points. Under current rules, you could do this with the vette for well under 500. 

 

What happens when I start with a 140hp variant of that 200hp engine?  Bolt on all the same aftermarket parts as the 200hp engine but the points end up different.

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1 hour ago, karman1970 said:

 

What happens when I start with a 140hp variant of that 200hp engine?  Bolt on all the same aftermarket parts as the 200hp engine but the points end up different.

Or a 129 hp 302 from a 1974 Maverick:

 

129 * 1.65 = 213 hp for a H/C/I/E 302...  riiiiiiight. 

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3 hours ago, TiredBirds said:

??? so our 305 (base 215hp) would be 322.5? (cam, intake, carb, headers)? Not sure we are there. 

You don't think 100 hp gain  (320 total) is possible with cam\intake\carb\headers on a stock casting 305? If your particular combo isn't then maybe drop one of the pieces that isn't adding the power that is possible with a good build.  

 

I totally spitballed those multipliers, we could move them as needed to be reasonable. I went high as starting numbers, just trying to show how it could work.  

 

 

1 hour ago, CBraden said:

Or a 129 hp 302 from a 1974 Maverick:

 

129 * 1.65 = 213 hp for a H/C/I/E 302...  riiiiiiight. 

 

Andrew has suggested in the past we take hp and torque to determine the power number (either take the higher, average, average and weigh the averages, etc). This could tame the really extreme mid 70's engines. Solid point you make, we still need to handle the most extreme smog examples (500 ci caddy anyone). 

 

Heads are the hardest part to evaluate, would be much easier if we forced the use of a head with a known power rating. Heads are the cornerstone of power development. 

3 hours ago, karman1970 said:

 

What happens when I start with a 140hp variant of that 200hp engine?  Bolt on all the same aftermarket parts as the 200hp engine but the points end up different.

 

You have that now. You would not have that if the multipliers were close to "estimating" your 200 hp build of a 140 hp engine. If you have a Miata you can't swap in 200 hp and be under 500 points, but you could swap in a 140 hp detuned engine and with cam\header\intake get it under 500 points and 200 hp. Assume the only difference between 140 and 200 hp spec of the oem motors is in the cam\header\intake, you could literally run a motor not legal to swap simply by claiming the math differently. 

 

 

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49 minutes ago, Black Magic said:

 

Andrew has suggested in the past we take hp and torque to determine the power number (either take the higher, average, average and weigh the averages, etc). This could tame the really extreme mid 70's engines. Solid point you make, we still need to handle the most extreme smog examples (500 ci caddy anyone). 

 

 

You shut your mouth.  How am I supposed to diesel-swap everything on the VPI list when you guys start talking like that? :)

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6 hours ago, Black Magic said:

 

It lives within the swap calculator, the forum search will show the math behind it and the theory when it was built.

 

Short answer.... in terms of estimated race weight to estimated crank hp....The 2797 "swap weight" rx7 just crosses the threshold at 200 hp (becomes more than 50 points swap cost). 2797 lbs /200 hp = 13.99 lbs \hp.  

 

In a practical sense you will need to be 12:1 to compete for the overall (crank not wheel hp to raced weight, full fuel). When the swap calc limit was set the 500 point car power limits were a bit closer to 13:1, weights were picked from the heaviest car to sort of get the practical limits back to 12-13 for the "legacy" cars. 

 

Engine mods were much more expensive in the past, VPI's were higher so fewer cars blew the as raced PWR apart. There was never real control over the effect of engine mods in terms of targeting a PWR, just fewer teams played in this area when it was a cheaper series. 

 

Long ago before swap rules, the "SX400" blew the PWR apart and created the swap calc with its non linear points applied after 14:1. Maybe GBU will finally force the same thing in regards to engine mods, swap weights and VPI (VPI already has started these corrections) 

OK, thx, that fills in a bit of the historical context and actually nails the PW topic on the head! As implemented it is an *implicit* cap. I assert you need an explicit one. GBU prob came in at indy between 7 and 7.5. (2800/425-ish). A built miata like the NC that just won at HH is prob around 9.5. An e30 pushing the m20 some and at a race weight of 2300 is around 12.5. 

 

I think the series would be well served by a hard cap around 8.75(give or take a bit). I also think it needs fixed tire allocations per weekend(note i said allocations *not* model prohibitions, or specs). Without these types of controls it will be hard to reign all of this in.

 

I've called out some other attributes of the system I think should be addressed, but those are secondary to the two above.

 

 

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29 minutes ago, atxe30 said:

OK, thx, that fills in a bit of the historical context and actually nails the PW topic on the head! As implemented it is an *implicit* cap. I assert you need an explicit one. GBU prob came in at indy between 7 and 7.5. (2800/425-ish). A built miata like the NC that just won at HH is prob around 9.5. An e30 pushing the m20 some and at a race weight of 2300 is around 12.5. 

 

I think the series would be well served by a hard cap around 8.75(give or take a bit). I also think it needs fixed tire allocations per weekend(note i said allocations *not* model prohibitions, or specs). Without these types of controls it will be hard to reign all of this in.

 

I've called out some other attributes of the system I think should be addressed, but those are secondary to the two above.

 

 

For comparison, I drove a WRL GP1 car in EC at Road America and would have had a top 3 lap time both days and did more laps than any other car over the weekend.

It is "only" 10.5:1 as-raced-weight/RWHP, and not optimized for ChampCar rules because of the min pit stop times.

A hard cap at 8.75, or even 9.5, would be a big jump from where 99% of ChampCars are today.  

 

Edited by ABR-Glen
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1 hour ago, ABR-Glen said:

For comparison, I drove a WRL GP1 car in EC at Road America and would have had a top 3 lap time both days and did more laps than any other car over the weekend.

It is "only" 10.5:1 as-raced-weight/RWHP, and not optimized for ChampCar rules because of the min pit stop times.

A hard cap at 8.75, or even 9.5, would be a big jump from where 99% of ChampCars are today.  

 

I am not sure even a few years from now that will be the case. The 2020 VPI has a 2003 Porsche Boxster at 520 points, and ready to race it is very close to 10.5 P/W... so the swap calculator is using a different metric than the VPI calcs - and in a couple years when the mid-2000's cars get VPIs, P/W will again move away from where it was historically. By 2010 Minivans had 300+hp (so did everything else).

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1 hour ago, atxe30 said:

. A built miata like the NC that just won at HH is prob around 9.5. 

 

 

Way higher maybe high 13s. 165whp is about max without cam on the NC. 

 

I don't think there are many 2hour per stint cars in chump that are below 12pwr. (That is full of fuel no driver / whp)

 

Edit:

What's the pwr of the fast Chumpcars at COTA? Don't think any of them is below 10? 

The 944 is like 185whp? And the mustang 200whp?

And the Miata 130 whp :) (that was obviously driver skill and not pwr that made that super fast)

 

 

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1 minute ago, turbogrill said:

 

Way higher maybe high 13s. 165whp is about max without cam on the NC. 

 

I don't think there are many 2hour per stint cars in chump that are below 12pwr. (That is full of fuel no driver / whp)

 

I think the 2 hr per stint metric is _highly_ track dependent. Our car is below 12 P/W and can go 2 hours at Hallett (and likely Harris Hill), but I would expect it to do significantly under 2 hours per tank at Daytona.

 

I know nothing of the car that won Harris Hill, but I have seen some (NC) Miata's that pulled interestingly hard in a straight line, when I had a slight run on them coming out of a corner. I have no idea what was in those engines, but it was reportedly only cammed. It added that platform to my potential racecars of the future list. 

 

 

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12 minutes ago, turbogrill said:

 

Way higher maybe high 13s. 165whp is about max without cam on the NC. 

 

I don't think there are many 2hour per stint cars in chump that are below 12pwr. (That is full of fuel no driver / whp)

well.....that car was consistently 2 secs faster than everyone else, including some well prepared miatas.

 

also the NC curb weight is 24xx, so race weight prob right around 1900. the stock 2L motor is 170 at the crank. That car had the vvt head on it as i recall, so plus whatever else, headers, etc. so lets say 185 at the crank. so PW would be 10.2. (so we are apple's to apples, i'm using hp at the crank as @Black Magic was above in his response).

 

 

 

 

 

 

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2 minutes ago, CBraden said:

 

I think the 2 hr per stint metric is _highly_ track dependent. Our car is below 12 P/W and can go 2 hours at Hallett (and likely Harris Hill), but I would expect it to do significantly under 2 hours per tank at Daytona.

 

I know nothing of the car that won Harris Hill, but I have seen some (NC) Miata's that pulled interestingly hard in a straight line, when I had a slight run on them coming out of a corner. I have no idea what was in those engines, but it was reportedly only cammed. It added that platform to my potential racecars of the future list. 

 

 

That car was spectacular really. It was immaculate and the build was top notch. Moreover it was freakin' fast. It really is a wonderful platform.

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1 hour ago, ABR-Glen said:

For comparison, I drove a WRL GP1 car in EC at Road America and would have had a top 3 lap time both days and did more laps than any other car over the weekend.

It is "only" 10.5:1 as-raced-weight/RWHP, and not optimized for ChampCar rules because of the min pit stop times.

A hard cap at 8.75, or even 9.5, would be a big jump from where 99% of ChampCars are today.  

 

I think you are right on the big jump (prob with the exception of some EC cars that visit from other series'.

 

To be clear, I back-o-the-napkin'd that number and any hard cap really should be data driven by as broad a sample as possible of dyno results (accounting for differences in dyno results, etc properly in the stats).

 

Done properly, the hard cap solves for the outliers like GBU, while allowing people to experiment and optimize within the spirit of the series.

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33 minutes ago, atxe30 said:

well.....that car was consistently 2 secs faster than everyone else, including some well prepared miatas.

 

also the NC curb weight is 24xx, so race weight prob right around 1900. the stock 2L motor is 170 at the crank. That car had the vvt head on it as i recall, so plus whatever else, headers, etc. so lets say 185 at the crank. so PW would be 10.2. (so we are apple's to apples, i'm using hp at the crank as @Black Magic was above in his response).

 

 

 

 

 

 

 

Got it!

I like to use the WRL way of doing PWR since you get access to much data. They classify using car ready full of fuel and using WHP (some specific dyno has to be used).

(Most NCs are in GP3)

 

These are the WRL COTA fastest lap times and their PWR:

 

• GP4 - Cars with a PWR of 18.1 to 22.0, 2:49

• GP3 - Cars with a PWR of 15.1 to 18.0, 2:43

• GP2 - Cars with a PWR of 12.8 to 15.0, 2:38

• GP1 - Cars with a PWR of 10.5 to 12.7,  2:32

 

I believe most fast chumpcars at COTA was about 2:40-2:43. So maybe the fast chumpcars at COTA had a PWR around 12?

 

(WRL allow for better suspension for less "points", so that makes the WRL cars a little faster).

 

If the GBU car had a PWR of 8, that is insane! If the other fast chumpcars are about 12!

 

 


 

 

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1 hour ago, CBraden said:

I am not sure even a few years from now that will be the case. The 2020 VPI has a 2003 Porsche Boxster at 520 points, and ready to race it is very close to 10.5 P/W... so the swap calculator is using a different metric than the VPI calcs - and in a couple years when the mid-2000's cars get VPIs, P/W will again move away from where it was historically. By 2010 Minivans had 300+hp (so did everything else).

The Pontiac GTO is 350-400hp and sub 10:1 from the showroom floor.  I think the G8 and the LT1 Corvettes and LS1 F-bodies are close in street trim.

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1 minute ago, karman1970 said:

The Pontiac GTO is 350-400hp and sub 10:1 from the showroom floor.  I think the G8 and the LT1 Corvettes and LS1 F-bodies are close in street trim.

Even the LT1 F-bodies are stout. 

They outclass our Cobra with ease.

285 hp vs. 240 hp

Aluminum heads vs. cast iron

SLA front suspension vs. modified McPherson strut

Factory panhard bar vs. 4-link Quadrabind

T56 (with double-overdrive and more aggressive gearing) vs. T5

Same fuel capacity

Similar curb weight

 

We were seriously looking at multiple Gen 4 F-bodies, but they are much harder to work on (engine is mostly under the cowl, challenging exhaust) and we felt more comfortable with the Mustang. But they absolutely outperform any Mustang from the same era. 

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