2.5 2012

carpenca said:
Latest updated Rules...

True 2.5” Inducer Bore NO CLIPPED WHEELS / NO BUSHINGS / NO
TAPERED COVERS
・ .200 MAX mwe Groove
・ No Hanging Weight Beyond Front Bumper (Ballast Permitted)
・ 8000lb Maximum (With Driver)
・ 26” Hitch Height
・ DOT Tires
・ No Dual pumps, no compressed gases or Power Adders of Any Kind
・ Diesel Fuel Only
・ Traction bars are allowed
・ Valid Registration and Proof of Insurance Required
・ Single Wheel Trucks Must Run Single Rear Tires, Factory Dual Rear Trucks are Permitted to Run Dual Rear Wheels

Caleb
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So... how is that really any different than say the 2.6 rules were before some of them went protrusion? I see no hanging weights - that just adds cost and complexity. I see no dual pumps - forcing guys to purchase big single pumps, I see turbo rules that are the same as the old 2.6 rules with the exception of the bore size and possibly a narrower MWE groove - so it still allows guys to go build S480/88 chargers with 2.5" covers on them.

What is the intent of "compressor blades must be perpendicular to the shaft"?

I see NO cost savings in this class if that is what it is suppose to be for. It looks to me like a bunch of guys can't get around the current crop of 2.6 trucks and want to make another class so they can win a blue ribbon. Next thing you know everyone will be complaining how the big bad 2.6 trucks are dropping down into the 2.5 class and beating up on them.
 
HotRodTractor said:
So... how is that really any different than say the 2.6 rules were before some of them went protrusion? I see no hanging weights - that just adds cost and complexity. I see no dual pumps - forcing guys to purchase big single pumps, I see turbo rules that are the same as the old 2.6 rules with the exception of the bore size and possibly a narrower MWE groove - so it still allows guys to go build S480/88 chargers with 2.5" covers on them.

What is the intent of "compressor blades must be perpendicular to the shaft"?

I see NO cost savings in this class if that is what it is suppose to be for. It looks to me like a bunch of guys can't get around the current crop of 2.6 trucks and want to make another class so they can win a blue ribbon. Next thing you know everyone will be complaining how the big bad 2.6 trucks are dropping down into the 2.5 class and beating up on them.
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They are saying the comp wheel must be in the 2.5 bore, no contouring of wheels etc. In theory it is great, enforcing that rule might be something else. The class will work great for awhile, until someone pushes the rules to the limit, then we will be talking about a 2.4 class...
 
That's why I say let the street trucks have a class. Quit trying to regulate power and turbos and take away the pulling modifications. You can't have your cake and eat it to. That's why we are where we are at with the currant 2.6. People couldn't hang with the 2.8 boys so they droped to th street class but then wanted all the 2.8 goodies. There are so many variations of street setups, why try to regulate that
 
zstroken said:
They are saying the comp wheel must be in the 2.5 bore, no contouring of wheels etc. In theory it is great, enforcing that rule might be something else. The class will work great for awhile, until someone pushes the rules to the limit, then we will be talking about a 2.4 class...
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The Validity of the class relies on the ability of the person teching to understand the concept of the class, and to tech it accordingly.

Caleb

PS This class was seen at the Fass Diesel Nationals in Indy this year.

http://www.nhrda.com/Flrz-2011/0610-Info.pdf

Pages 8-11
 
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carpenca said:
The Validity of the class relies on the ability of the person teching to understand the concept of the class, and to tech it accordingly.

Caleb

PS This class was seen at the Fass Diesel Nationals in Indy this year.

http://www.nhrda.com/Flrz-2011/0610-Info.pdf

Pages 8-11
Click to expand...


That is always the case, but what happens when trucks with $4000 chargers, heavy ported engines, and 3000 cp3 start showing up in the class and whooping on the others? Folks will cry for a 2.4, then 2.3, then 2.2.

I agree it would be nice to have a budget class, but look at garden tractor pulling, you have folks buying aftermarket blocks for those classes.
 
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What a thread! There are lots of good ideas in here; its just that some of them are hard to put into effect because of time and man power limitations in teching, etc...

Personally; and i only pull once in a while, so take my opinion for what its worth, Id like to see the 2.6 class dropped and have a 2.5 class and a 2.8 class in effect. Somehow limit the 2.5 class to a charger with a straight 2.5 bore with the wheel protruding into the housing, no busings, etc... Obviously this part is where the rules always get hard to make and i dont have a perfect solution for teching the chargers, but something like an S465 would be the model turbo for the class. I believe this way, even a charger like a 64/71/14 or even a good 62 could be pretty competitive, and those are actually reasonably streetable chargers. Probably not gonna win with an S300 based charger(unless the class was limited to a small frame), but you arent gonna look stupid either. By eliminating the 2.6 class you really havent hurt anybody either. Now all the 2.6 trucks can just pull their bushings out and go back to 2.8. They dont even have to spend any extra $$ this way.

Here is our 2.5 class at stanfords diesel mania in 08

[ame="http://www.youtube.com/watch?v=md6WqJ7SekA"]http://www.youtube.com/watch?v=md6WqJ7SekA[/ame]

Lots of those trucks had stock chargers too. You can see most everyone was in the ball park. The 6.0 powerstroke at 1:10 only has an SCT tune, a decent setup and stock transmission. He got beat obviously, but not murdered. The old gray flatbed 12 valve at 3:05 had nothing but some full cut DV's, stock turbo, and a good clutch. This was just a great class IMO. Even a street truck with a decent setup could come in and be competitive and have a lot of fun. I have a stock 3rd gen charger on my truck, but as far as im concerned, it wouldnt bother me to group work stock into a 2.5 class like this instead of making them 2 seperate classes. It would cut down on tech time and they would still be competitive.

Some of you guys will say this is a pulling class and that its not affordable for everyone and everyone cant win, etc... I understand that, but I do think the class could be made more affordable. A class like this( IF you could keep it this way) would be great for most street trucks. It just seemed to me like the class was a lot more fun to watch when it was like this instead of the current 2.6.

Not saying any of this will ever happen again, just dreaming of days past i reckon....
 
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zstroken said:
That is always the case, but what happens when trucks with $4000 chargers, heavy ported engines, and 3000 cp3 start showing up in the class and whooping on the others? Folks will cry for a 2.4, then 2.3, then 2.2.

I agree it would be nice to have a budget class, but look at garden tractor pulling, you have folks buying aftermarket blocks for those classes.
Click to expand...

Dead on!!! Very predictable, it's happened many times.
 
Cummins Driver said:
What a thread! There are lots of good ideas in here; its just that some of them are hard to put into effect because of time and man power limitations in teching, etc...

Personally; and i only pull once in a while, so take my opinion for what its worth, Id like to see the 2.6 class dropped and have a 2.5 class and a 2.8 class in effect. Somehow limit the 2.5 class to a charger with a straight 2.5 bore with the wheel protruding into the housing, no busings, etc... Obviously this part is where the rules always get hard to make and i dont have a perfect solution for teching the chargers, but something like an S465 would be the model turbo for the class. I believe this way, even a charger like a 64/71/14 or even a good 62 could be pretty competitive, and those are actually reasonably streetable chargers. Probably not gonna win with an S300 based charger(unless the class was limited to a small frame), but you arent gonna look stupid either. By eliminating the 2.6 class you really havent hurt anybody either. Now all the 2.6 trucks can just pull their bushings out and go back to 2.8. They dont even have to spend any extra $$ this way.

Here is our 2.5 class at stanfords diesel mania in 08

http://www.youtube.com/watch?v=md6WqJ7SekA

Lots of those trucks had stock chargers too. You can see most everyone was in the ball park. The 6.0 powerstroke at 1:10 only has an SCT tune, a decent setup and stock transmission. He got beat obviously, but not murdered. The old gray flatbed 12 valve at 3:05 had nothing but some full cut DV's, stock turbo, and a good clutch. This was just a great class IMO. Even a street truck with a decent setup could come in and be competitive and have a lot of fun. I have a stock 3rd gen charger on my truck, but as far as im concerned, it wouldnt bother me to group work stock into a 2.5 class like this instead of making them 2 seperate classes. It would cut down on tech time and they would still be competitive.

Some of you guys will say this is a pulling class and that its not affordable for everyone and everyone cant win, etc... I understand that, but I do think the class could be made more affordable. A class like this( IF you could keep it this way) would be great for most street trucks. It just seemed to me like the class was a lot more fun to watch when it was like this instead of the current 2.6.

Not saying any of this will ever happen again, just dreaming of days past i reckon....
Click to expand...

Like the local drag track finally got its 1st diesel truck event last Oct. They ran heads up. A lot of trucks showed up and they pretty much got into an order after a couple of hours where similar time truck lined up. The stock trucks did not want to be beside the hood stacked, 2.6" truck that spooled forever. The beating was horrible. But eventually the trucks got sorted out.

Even in drag racing, in brackets mostly, stock trucks had fun. Why? Entry level competition. If sled pulling happens like the tractor pullers, fewer and fewer new blood is gonna show up.

A stock appearing truck, 2.5" class with a weight limit, traction bars, maybe weight hanging, will be good for the sport.

But don't be fooled by my writings. I still love the tube idea. :blahblah1:
 
If its not a stock appearing class then who will be the first to build a 2.5 spec hx60 for the class.
 
zstroken said:
They are saying the comp wheel must be in the 2.5 bore, no contouring of wheels etc. In theory it is great, enforcing that rule might be something else. The class will work great for awhile, until someone pushes the rules to the limit, then we will be talking about a 2.4 class...
Click to expand...

Quoted from the rulebook:

Turbocharger: The turbocharger is limited to a direct bolt on. No adapter plates allowed. T4 foot limit. With an inducer bore of 2.5 limit, measured with a 2.55 plug with zero tolerance. 6.4 liter powerstroke engines may utilize the factory compound-turbo configuration.
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This rule allows for me to build an S480/88 with a T4 foot on it with a custom cut 2.5 cover. In fact with this rule - this class would most likely rock out with more power than the current crop of 2.6 trucks using protrusion rules - or at the very minimum it would be very difficult to tell them apart other than lack of hanging front weights. How is this class going to benefit the sport?
 
YOU CAN NOT DO CUSTOM COVERS ITS A STRAIGHT BORE CLASS. REPEAT NO 480S WITH 2.5 COVERS. IT 100% OF A TRUE BORE 2.5 CLASS. NO MORE NO LESS.

True 2.5” Inducer Bore NO CLIPPED WHEELS / NO BUSHINGS / NO
TAPERED COVERS
THIS has been said 20 times now guuys there are not custom covers or hx 60 ever going to be in this class cause it wont be a true 2.5 charger
 
I think this last Fleece pull was a good testiment to what a good set of rules of a 2.5 class and a stock turbo class can do!!!

I think there was close to 20 Stock turbo trucks, and it wasnt like watching a MPH antique tractor class!! Good trucks came out and put on a great pull, then there were 15 or so trucks in the 2.5 class and I dont believe many, if any trucks were jumping classes.

All in all, there wasnt a lot of whining about rules, guys trying stupid stuff to sneek in turbos and all that crap. If anything, it showed that 2.5 following is growing pretty quick!!!

Between 2.5, 2.6 and 3.0 it can make one heck of a show!!!
 
I dont like the term true 2.5 or what ever size. Because in your terms all it has to do to be a true 2.5 turbo is a compressor wheel with a countoured wheel instead of one thats clipped. Its just a different way of getting to the same end result.
 
Are you sure that no box stock charger out there has a MWE greater than .200 from the factory???
 
97rada said:
YOU CAN NOT DO CUSTOM COVERS ITS A STRAIGHT BORE CLASS. REPEAT NO 480S WITH 2.5 COVERS. IT 100% OF A TRUE BORE 2.5 CLASS. NO MORE NO LESS.

True 2.5” Inducer Bore NO CLIPPED WHEELS / NO BUSHINGS / NO
TAPERED COVERS
THIS has been said 20 times now guuys there are not custom covers or hx 60 ever going to be in this class cause it wont be a true 2.5 charger
Click to expand...

Hmm apparently you haven't seen a custom cover/turbo that's a true straight bore .:doh: A HX60 can be made with a straight bore 2.5 and custom wheel with protrusion and you will never no it . You wont see no weld no taper or clipped wheel
 
With the ability of the turbo companies to make any turbo fit into any class it needs to be limited to a small frame turbo. That's gonna be the only way to keep it from getting out of control IMO.
 
It does seem like limiting it to a small frame turbo might be a good idea, but how would you go about that? Might open a whole new can of worms there. Or else you will have people still running large wheels and custom housings etc.. on a small frame turbo.
 
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Use a OD limit of the compressor housing I believe most holsets of the Hx35/ He and S300s are very close . One would need to gather some from Garret Dmax line and go from there. Say a S364 measures 9 1/2 put a 10in limit on the housings just as an EXP
 
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