Common Sense

Smokem

Smokem

Turbler
Read carefully;

1. Smooth bore turbochargers will not be less expensive.
2. Smooth bore turbochargers will not decrease the current power level.
3. Smooth bore turbochargers will not “level” the playing field.
4. Changing to smooth bore will force every competitor in PPL as well as multiple subsequent organizations using their rules to purchase at the very least a new compressor cover and compressor wheel.
5. Smooth bore was a great idea, 5yrs ago.

Here is the most logical solution, keeping the puller’s best interests in mind.

1. Add a maximum outside diameter measurement to the MWE groove.

This will allow the vast majority of competitors to keep their current turbochargers, and it will also greatly reduce the “power gap” that is currently an issue. This will simplify the tech procedure, and it will remove the grey area from the rule wording.

These are facts, not opinions. I am simply giving the people whom this will affect the knowledge they need to make an educated decision. Be careful to unknowingly push for a change that you may regret in the future, that has already happened to these classes once.
 
Example for the 2.6" class;

The MWE groove can have an outside diameter no greater than 3.500", and have a width no larger than 0.200" at any point.


Example for the 3.0" class;

The MWE groove can have an outside diameter no greater than 4.200", and have a width no larger than 0.250" at any point.
 
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If someone wants to stay competitive, they're going to be purchasing a wheel or at least a cover this winter regardless. Part of the trouble is incompetent tech officials. I'm not talking about PPL, but the other smaller organizations that follow their rules. Some of them would do well to even identify the map groove. A monkey could tech a smooth bore turbo. I like the idea of the smooth bore rule. No matter the rule there will always be turbo updates that will be available, but with a smooth bore, you cut out all the trick cover BS and it basically comes down to wheel design. Since smooth bore turbos have been around for a long time, the wheel technology is already there. If there's an charger update, the gains will be more like 10-15hp rather than 80-90 like you see now.

I feel like your proposed rule leaves a huge grey area
 
BluegrassDiesel said:
I feel like your proposed rule leaves a huge grey area
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No, it doesn't.

BluegrassDiesel said:
I like the idea of the smooth bore rule. No matter the rule there will always be turbo updates that will be available, but with a smooth bore, you cut out all the trick cover BS and it basically comes down to wheel design.
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What I proposed will do the same. The power gains this year have not come entirely from "trick cover BS", it seems as though you may be misinformed.
 
I can tell you this year at Hillsboro we essentially had to dissemble our turbo because someone had an adjustable groove. They were able to open it up by just turning the inner bore.
 
takedown95 said:
I can tell you this year at Hillsboro we essentially had to dissemble our turbo because someone had an adjustable groove. They were able to open it up by just turning the inner bore.
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They should get a year and 10 days for that BS!!!
 
Smokem said:
The location of the pinch point, meaning where the groove measures 0.200" in it's width, it must also only measure 3.500" in total diameter. There is no point to over complicate where the issue lies.
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Draw a pic. I understand what your saying but some may not. At 3.500 you are pulling #x of air. But move the opening out to 7" and the area of the map Grove just doubled in size and the .200 is now no restriction.
 
Let me be clear, there is no "magic" in these covers as many would have you believe, it is simple math, an additional 3 in² of surface area is going to make more power. You restrict the total surface area and you restrict the power, and you don't need smooth bore to make that happen.
 
A MWE groove should not be allowed to feed air toward the wheel. It should only open up back towards the intake. When that changed is when things went off track. Allowing any air into the turbo besides the 2.6 or 3.0 bore is rendering the rule useless.
 
To make things simple to tech the classes should be identified as a single turbo class with a maximum T3 and T6 exhaust housing instead of 2.6 and 3.0 inlet size, which is really unlimited with the current MWE groove interpretation.
 
Smokem said:
Even a traditional style MWE groove will pull air in near choke condition.
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How is that? A traditional MWE groove is intended to allow air to escape back towards the intake when the wheel slows down faster than the air is flowing in.
 
Smooth bore simplifies it immensely. A true 2.6 or 3.0 smooth bore would never hang with the bull**** MWE stepped wheel combo's out now.

With that it's sure not going to cheapen up charger's and it forces everyone to buy a new charger so it's still a lot of suck.
 
Smooth bore is the real solution, but there could be a simpler alternative if tech was up to par, which is wishful thinking unfortunately.

Not only does it suck to force every competitor to buy a new turbocharger, but what many probably don't even consider is how much time and money has been spent on protrusion setups, only to be discarded.
 
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I am totally new to this sport. I have been building truck this summer. As a newbe a smooth bore turbo makes more sense. Better yet a spec turbo would be ideal 1 rule and stick with it. Dirt track we used to run had carb rule run spec carb or dont run. not the most expensive but is the same for as long as i remember.
 
As a local club tech that has ppl rules in place, it would be great to see the smooth bore pass. I always look at the rules from a tech prospective first. With a smooth bore I can give any board member a slug and know that every truck will be teched the same. I personally can't tech every truck at every pull all season. I also have a hard time explaining turbo rules to a super stock or modified gas/alcohol tech. They just don't care. However, if I give them the slug and tell them to check the inlet, the playing field is level. So even though it would mean I personally would need a new wheel and cover, I vote smooth bore every time this comes up. You can not cheat or mistech smooth bore. It keeps the class simple.
 
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