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TiredBirds

dumb question swap vs turbo

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So as I understand it one could swap a motor and get charged X per HP gain... BUT if a team had 100 points to spare and used a turbo it's all good? Just asking because in theory one could make much more HP with a turbo  than a simple swap (American V8 anyway) Now say I use the same engine and boost it. I'm still making that power, or more and I'm still under 500 points right? 

Example: 

Make: Chevrolet
Model: Camaro
Year: 1988
VPi: 200
Car Weight: 3026
Original HP: 220
New HP: 315
Points Added to VPi: 2236
--->NEW VPI: 2436

 

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Yes that's right, most people have not exploited the gaping turbo loop hole because of fear it would be closed immediately and/or not enough fuel to make 2hours.

Most of the Chumpcar rule book is in the top loop.

image.png.8224e6edd3049b0b44793fc00d232a90.png

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5 minutes ago, morganf said:

Yes that's right, most people have not exploited the gaping turbo loop hole because of fear it would be closed immediately and/or not enough fuel to make 2hours.

Most of the Chumpcar rule book is in the top loop.

image.png.8224e6edd3049b0b44793fc00d232a90.png

Well for teams like us that can't make 2 hours anyway......  

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You would be better off using a "tanker", like rx7 to do this. 944 would be another good choice. 

 

You can also build more power with other engine mods (besides turbo) for points to allow a power to weight beyond what the calculator allows. This is pretty typical for the good FWD cars, and their low vpi allows it (perhaps in a needed way, power gain to offset not being rwd). 

 

This is the nature of our rules having such a strict outlook on non primary performance factors (power, weight, suspension type), you end up rationalizing a very low vpi for a car to allow mods to match your benchmark cars stats(like coolers). When they choose power over the stuff you expected unicorns pop up. Prime example several months ago, lots of room to put big power in a tbird, and teams are right saying they need suspension, hubs, diff,trans, coolers, engine, knuckles to equal say an e30. Average teams need the points to swap this stuff. A top level builder could make that car work without alot of those mods, and spend the points to massacre the power to weight....

 

That is the counter to the "no free stuff" theory, if you make all parts have value and we have to reduce the vpi of cars to account for it, you will have big discrepancies when a team finds out they can make the oem stuff work. If we have to factor in items like springs and bushings, the t bird might have a negative vpi, and the first squad to make oem work will mop the field. 

 

I petitioned to have more things included in a "package" for these current low vpi cars, defining a little more where the points would go. We could also make the rules more open in some areas and up the vpi of cars we formerly evaluated based on the need (ie coolers are not points, but non cooler cars vpi goes up as needed). This would be getting points back to primary performance factors, and actually balancing these vs seeking equity through a points system that rates coolers nearly as high as a long tube header....

 

You are slightly blessed that the BSFC of a turbo engine and heat make endurance racing harder, although todays new (good) turbos are moving that line. 

Edited by Black Magic
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13 minutes ago, Black Magic said:

You would be better off using a "tanker", like rx7 to do this. 944 would be another good choice. 

 

You can also build more power with other engine mods (besides turbo) for points to allow a power to weight beyond what the calculator allows. This is pretty typical for the good FWD cars, and their low vpi allows it (perhaps in a needed way, power gain to offset not being rwd). 

 

This is the nature of our rules having such a strict outlook on non primary performance factors (power, weight, suspension type), you end up rationalizing a very low vpi for a car to allow mods to match your benchmark cars stats(like coolers). When they choose power over the stuff you expected unicorns pop up. Prime example several months ago, lots of room to put big power in a tbird, and teams are right saying they need suspension, hubs, diff,trans, coolers, engine, knuckles to equal say an e30. Average teams need the points to swap this stuff. A top level builder could make that car work without alot of those mods, and spend the points to massacre the power to weight....

 

That is the counter to the "no free stuff" theory, if you make all parts have value and we have to reduce the vpi of cars to account for it, you will have big discrepancies when a team finds out they can make the oem stuff work. If we have to factor in items like springs and bushings, the t bird might have a negative vpi, and the first squad to make oem work will mop the field. 

 

I petitioned to have more things included in a "package" for these current low vpi cars, defining a little more where the points would go. We could also make the rules more open in some areas and up the vpi of cars we formerly evaluated based on the need (ie coolers are not points, but non cooler cars vpi goes up as needed). This would be getting points back to primary performance factors, and actually balancing these vs seeking equity through a points system that rates coolers nearly as high as a long tube header....

 

You are slightly blessed that the BSFC of a turbo engine and heat make endurance racing harder, although todays new (good) turbos are moving that line. 

Our motor is not 220hp but that is the number listed in the VPI as stock.  A turbo would greatly enhance the performance, even with low boost. With a +2 cell we could likely make almost 2 hours. 

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1 minute ago, TiredBirds said:

Our motor is not 220hp but that is the number listed in the VPI as stock.  A turbo would greatly enhance the performance, even with low boost. With a +2 cell we could likely make almost 2 hours. 

 

You will end up roughly 15 to 20% more fuel burn for the same hp as a NA motor...

 

Adding power while adding turbo is sort of doubling down on the added fuel consumption. 

 

Otherwise you have a good motor to do a low boost setup. Cooling being the next hurdle....

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16 minutes ago, Black Magic said:

 

You will end up roughly 15 to 20% more fuel burn for the same hp as a NA motor...

 

Adding power while adding turbo is sort of doubling down on the added fuel consumption. 

 

Otherwise you have a good motor to do a low boost setup. Cooling being the next hurdle....

water/meth injection a.k.a washer fluid.  We are not likely to take this on, but just pointing out what can be done.  Also you are correct about the fuel burn BUT if you shift at 5k insted of 6 and use 5th on long straights that could offset some of the fuel issues while still having a faster car... possibly.

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40 minutes ago, TiredBirds said:

water/meth injection a.k.a washer fluid.  We are not likely to take this on, but just pointing out what can be done.  Also you are correct about the fuel burn BUT if you shift at 5k insted of 6 and use 5th on long straights that could offset some of the fuel issues while still having a faster car... possibly.

 

So would making nearly the same power at higher bsfc (good na engine). 

 

I would think a turbo to be a better tool for a 350ish point car, if you have lots of vpi room na build could be alot better. 

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Some of us have been maximizing fuel usage for years now. ;)

 

Suffice it to say that by using a lot of power during the first half of the straight then a lot less for the rest of the straight, you can maintain a particular pace while using less fuel or, of more interest, go faster on the same fuel.

 

The method used to increase your power output will determine how much fuel saved or how much faster you can go. With a turbo, you're designing in about a 10% decrease in BSFC. If you can make the same power by other means, you'll be that 10% farther ahead.

 

However, if your engine can handle large amounts of boost at moderate rpm, you can overcome that deficit by making power at the most efficient part of the straight, which is right off the corner. Making and using 300 hp for the first third of the straight then essentially coasting for the rest will be faster than averaging 150 hp for the whole straight.

 

People complain about V8s having torque but seem to forget that turbos are basically V8s in 4 or 6 cylinder disguises. I built a 4.3 V6 that made 530 ft.lbs of torque on 9 psi (twin Dodge 2.2 turbos) and pump gas. That works out to about 300 hp at 3000 rpm. You may need to replace rear tires more often. :)

Edited by mender

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14 minutes ago, mender said:

People complain about V8s having torque but seem to forget that turbos are basically V8s in 4 or 6 cylinder disguises. I built a 4.3 V6 that made 530 ft.lbs of torque on 9 psi (twin Dodge 2.2 turbos) and pump gas. That works out to about 300 hp at 3000 rpm. You may need to replace rear tires more often. :)



A blow through carb SBC turbo would be a hoot in Champcar. 

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How much less reliable is a turbo car than a NA?

 

From what I remember all turbo chump cars I have seen has blown up and not make the race. (Miatas spewing rods, Audis smoking like crazy, RX7s just not working )

 

Is the problem the NA->Turbo conversion or turbos in general. 

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Just now, turbogrill said:

How much less reliable is a turbo car than a NA?

  

From what I remember all turbo chump cars I have seen has blown up and not make the race. (Miatas spewing rods, Audis smoking like crazy, RX7s just not working )

  

Is the problem the NA->Turbo conversion or turbos in general. 

.

My turbo d16 was more reliable than NA D16's. Because it had so much more tq at lower engine speeds I was able to keep the piston speeds much lower by short shifting. 

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23 minutes ago, turbogrill said:

How much less reliable is a turbo car than a NA?

 

From what I remember all turbo chump cars I have seen has blown up and not make the race. (Miatas spewing rods, Audis smoking like crazy, RX7s just not working )

 

Is the problem the NA->Turbo conversion or turbos in general. 

 

Poor turbos (bad efficiency) = lots of heat (air and oil\water) = little margin in tuning = boom

 

Bad engine controls were also factors, I think with the ECU's you can run now there is a lot better chance of keeping it together. 

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26 minutes ago, turbogrill said:

How much less reliable is a turbo car than a NA?

 

From what I remember all turbo chump cars I have seen has blown up and not make the race. (Miatas spewing rods, Audis smoking like crazy, RX7s just not working )

 

Is the problem the NA->Turbo conversion or turbos in general. 

 

For turbo wins see the Doorslammers Miata at Sonoma or most any race RBank enters with their Saab’s.  

Edited by Ron_e

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4 minutes ago, Black Magic said:

 

Poor turbos (bad efficiency) = lots of heat (air and oil\water) = little margin in tuning = boom

  

Bad engine controls were also factors, I think with the ECU's you can run now there is a lot better chance of keeping it together. 

 

I kept mine together with stock ECU, only lost one Headgasket the entire season. Pulled lots of timing, Max'd out the duty cycle of the injectors for pretty much anything over 3/4 throttle , crushed the stock FPR which gave us about 10psi more pressure, but we did run well within the efficiency curve of the compressor. 

 

*chipped stock ECU

Edited by red0
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1 hour ago, Black Magic said:

 

So would making nearly the same power at higher bsfc (good na engine). 

 

I would think a turbo to be a better tool for a 350ish point car, if you have lots of vpi room na build could be alot better. 

the build is pretty good considering we already have Cam, headers, pulley, and headers. Even with intake/carb we are at 385. Not sure what more we can do except jump to a 350 (and that would be no points) and work on our driving ;)  

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26 minutes ago, Black Magic said:

 

Poor turbos (bad efficiency) = lots of heat (air and oil\water) = little margin in tuning = boom

 

Bad engine controls were also factors, I think with the ECU's you can run now there is a lot better chance of keeping it together. 

we run a carb...no need for that pesky computer junk. Our engine control is a timing light and a vacuum gauge. 

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1 minute ago, TiredBirds said:

we run a carb...no need for that pesky computer junk. Our engine control is a timing light and a vacuum gauge. 

 

The engine wiring must be sooooo nice. 

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7 minutes ago, TiredBirds said:

the build is pretty good considering we already have Cam, headers, pulley, and headers. Even with intake/carb we are at 385. Not sure what more we can do except jump to a 350 (and that would be no points) and work on our driving ;)  

Side skirts, sucker fans, and a snowmobile engine.  Probably like 20 points because Champcar aero rules.  Then huge fenders and some 335 rubber.

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1 minute ago, karman1970 said:

Side skirts, sucker fans, and a snowmobile engine.  Probably like 20 points because Champcar aero rules.  Then huge fenders and some 335 rubber.

I have an NOS kit...lol  we already run 275/40/17's... Maybe front and rear wings? 

8 minutes ago, red0 said:

 

The engine wiring must be sooooo nice. 

easy anyway... New build will be a tad more "neat"... 

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Stock turbo cars vs. Add-on turbo cars are much different scenarios. Very few add-on turbo cars have been reliable and successful - Andrews D16 Turbo civic sedan being one of the few (in a single season, won a race and got 2x 2nd places I believe, and Condren wrote a new turbo rule for it).

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1 minute ago, Slugworks Paul said:

Stock turbo cars vs. Add-on turbo cars are much different scenarios. Very few add-on turbo cars have been reliable and successful - Andrews D16 Turbo civic sedan being one of the few (in a single season, won a race and got 2x 2nd places I believe, and Condren wrote a new turbo rule for it).

 

Yea, I was smart enough to buy it from a guy who spent years doing R&D on the setup. The car was far from dominant though, pretty good, but not crazy good or anything. 

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16 minutes ago, TiredBirds said:

I have an NOS kit...lol  we already run 275/40/17's... Maybe front and rear wings? 

easy anyway... New build will be a tad more "neat"... 

Cheaty fiberglass hood should eat up some points

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