2.5 turbo rule

[zstroken]

DHRA Indy Nationals 2.5" Class

http://www.youtube.com/watch?v=dBSEPcUz4Vk

This is the standard, this is why multiple organizations need to get on the same wave length with the 2.5" class, so that trucks from several states can compete at national level, televised events. These are not $100,000 2.6" pulling trucks, these are mostly farm trucks with a couple major mods... The best part is there are a couple Haisley/SMT Machine built trucks that pull 2.5" with all the fuel in the world in there pimped out P-pumps, and yet they still are not anything special on race day. The three minute P-Pump Spooler is a little proof that pouring the fuel to it, dont mean its gonna make HP.

By the way, for those following along at home that are unaware. The Rules were the Fleece/ITPA 2.5" Package.

Caleb

One thing I have heard an issue is, the cutting of leave springs to clear wide tires, not for sure if that is happening, but IMHO should not be allowed.

 

[paul06d-max]

White D-max? That truck bumped up to 2.6 after that pull... Cutting the leaf springs isnt something I would ever do.. They take alot of stress I wouldnt take anything away from them....

I understand that not every 2.5 truck might not still be a street truck, in the same though I know that there are a good bit of guys that still drive them... after all what's the point in having a 750-800hp truck that you cant drive that just go's 300ft at a time... most all of these trucks are newer as well so I wouldnt ever do anything to make it be something that you could'nt drive most all of them are way to much fun on the street to let them sit in a garage...

 

[revolutiondsl]

I didnt do so hot but normally I finish top 5 around here and I only have 120 hp injectors and an LBZ cp3 and my head has never been off. I havent even studded it yet. The 2.5 class works around here and is picking up steam. A lot of the little local pulls are doing a 2.5 and open now because of the popularity. Camden Indiana is doing one saturday. I think if I get some more fuel it will run a lot better but for now it holds it own.

 

[Sancrest]

I wish we could get more trucks, that is why we started this class. We only get 1 or 2 trucks at each pull. I think I may go to 2.6 next year just so I have more options for pulling and don't get beat everywhere I go because we are out horsed. I like the 2.5 class, you can go pull every week and not spend all week working on the drive train because you are making more HP than it can handle. I have seen a lot of tranny, transfer, and rear end carnage this year. They can handle 800 hp and lower with just a few mods and you can have fun. I pull for fun not to try and beat everyone every week.

 

[Smokem]

How is 800hp an entry level class.... ppl need to stop calling it entry level...a true entry level is stock.

I clearly stated it is not work stock, nor an enty level class, no one wants to watch 450hp trucks pull a sled, let's be honest.

no air to water allow hanging wieghts and duals if u guys say u dont need them fine dont run them but let the guy that wants to , there ya go.

Who wouldn't want to? That is the point. If you let the class have six 35" tires @ 8000lbs you might as well let them have drawbar hitches, because people will want those too.

 

[kino_fab]

honestly, i don't think dual tires is going to matter that much. It's not like it costs $4000 to put them on a single wheel truck. Probably even keep some guys from wanting to pull since some will not want to take the time to put singles on then turn around and put them back on to pull at other places. If you want to run draw bar hitches, so be it. It's not that hard or expensive to make one.

You guys are thinking way too hard on this. Chassis and tire setups are not going to make this a more limited class, not to mention just a turbo limit. Other engine rules need to be enforced to really limit the power of this class. You take a fully built 2.6 truck making over 1000hp, just throw a turbo on it that meets a rule saying 2.5 turbo, will be checked with a 2.55 plug, and it probably is still going to make over 1000hp. Now, take that same truck, put a stock cylinder head on it, a single pump, or a 12mm auto gov, and a box stock S463 with an exducer limit, and that truck isn't going to perform much better than a guy with a the same external mods and a bone stock internal engine.

 

[oldestof11]

Fuel and air limit HP.

I have come to the conclusion that no matter the new way to limit HP, it is useless unless 1) Someone has the balls to tech it and 2) It limits quantifiable amount of either air, fuel, or both.

Tech a size will NOT limit HP as there is this little thing called innovation that will cost someone but they will pay to get the edge.

 

[Smokem]

honestly, i don't think dual tires is going to matter that much. It's not like it costs $4000 to put them on a single wheel truck.

Honestly, I think it does matter, and it would cost less to put a single tire on a dual chassis.

If you want to run draw bar hitches, so be it. It's not that hard or expensive to make one.

So be it? Just let it slide right? Because that worked so well for the 2.6" class.

You take a fully built 2.6 truck making over 1000hp, just throw a turbo on it that meets a rule saying 2.5 turbo, will be checked with a 2.55 plug, and it probably is still going to make over 1000hp.

If it is a native wheel, no it won't. Take a 63/90mm wheel and dyno it vs a 63/102mm wheel, see how much hp it gains.

Now, take that same truck, put a stock cylinder head on it, a single pump, or a 12mm auto gov, and a box stock S463 with an exducer limit, and that truck isn't going to perform much better than a guy with a the same external mods and a bone stock internal engine.

This is overthinking it, or over regulating things that will never be teched unless protested, which will lead to the class death because no one will ever get to pull.

 

[moparmcg]

2.5 Work Stock Class
• • True 2.5” Inducer Bore NO CLIPPED WHEELS / NO BUSHINGS / NO
TAPERED COVERS Teched with a 2.55" Plug
• • .200 MAX mwe Groove
• • 6.4 Powerstrokes will be permitted to run modified turbos, as long as the atmosphere turbo (Big Turbo) does not exceed the OEM straight bore dimension. (2.59") NO TAPERED COVERS will be permitted.
• No Hanging Weight Beyond Front Bumper (Ballast Permitted)
• 8000lb Maximum (With Driver)
• 26” Hitch Height
• DOT Tires 35" Height Limit
• Dual Pumps will be Permitted
• Diesel Fuel Only
• Traction bars are allowed Drive Shaft Loops/Shields are Recommended, but not mandatory
• Valid Registration and Proof of Insurance Required
•Dual Rear Wheels on non OEM Equipped Trucks will be Permitted


ITPA, NHRDA, Pretty much anywhere you go in IN..


The best rule I saw from Central Ohio truck pullers... 3. No crying!!!!!

I like these rules the best for being a little guy building my truck for 2.5 and trying to be competitive , only thing i would like to see is hanging weights since i have a rclb and i'm well under weight compared to newer 4dr trucks

 

[Backwoods]

I clearly stated it is not work stock, nor an enty level class, no one wants to watch 450hp trucks pull a sled, let's be honest.



Who wouldn't want to? That is the point. If you let the class have six 35" tires @ 8000lbs you might as well let them have drawbar hitches, because people will want those too.

Yes i know nobody wants that i wasn't referring to u in saying its not stock. A lot of posts keep saying its entry level we all know its not......


How can u tell one guy he cant run duals yet let the guy who bought a dually run 35" duals all the way around!!!!!!

So now your gonna make him strip his outter tires? Thats stupid! Or your gonna tell guys what tires theu have to buy?

 

[Smokem]

I've said no duals period, on several occasions. By allowing duals, you are telling them what tires to buy.

 

[kino_fab]

How do you figure protests would be the death of the class, and why would that not let anybody pull? If that were the case then non of the other pulling classes that have been around since before the majority of us have been born would be around either i guess. Even every other form of motorsport is doomed then. You heard it guys, Might as well just sell all of our toys for scrap and buy cheap daily drivers from now on.

 

[Smokem]

So you suggest we do what? Tech the compressor exducer, plunger size, valve size, possibly even cubic inch? This under normal inspection, or just under a protest situation, and with such stringent regulation you don't forsee many protests happening? You did not answer the power question with the difference in exducer size either.

It's simple, as has been said all along, the rules are in place and work. But there should be a few stipulations added to keep them working. I say let them hang weight and only allow a single tire, is that so hard to understand?

You wish to compare to classes that have been around for some time, insinuating gas pulling classes, how many allow duals?

 

[Backwoods]

I've said no duals period, on several occasions. By allowing duals, you are telling them what tires to buy.

That rule will turn ppl away quickly. If there are 2 pulls the same night the same distance away and guys have duallys from factory and just wanna pull for fun where u think they will go? They surely arent going to the place with a rule that says ok drop down to a single 245/70/16 road tire u have and pull againt single wheel trucks with 33x12.5's since u say no 35's id assume thata the tire most would run

 

[zstroken]

While the protest is a rule, it doesn't get used on the big time consuming options. U want simple rules that can be teched before the class. Someone dqd after the facted is retty irrelevant. Especially if it is a local pull and someone wants to beat his buddy etc. If ur concerned about hp, make it a 2.4 class. You won't keeppp the money out of the class with rules. If you believe more rules fix things, maybe yu should be a politician.

 

[kino_fab]

It's not like there is going to be a protest every night on every truck, and even if there was it's not like it would be a major tear down that would take all night. I said nothing about valve size, just the no porting. I understand what your saying about making teching easy. Like I said beforfe, the initial tech inspection would be visual only and plugging the turbo. A complete tech would only take less than 5 minutes. As for a vehicle being protested, not every thing in the rules would be checked, only what is specified by the protester. Everything I mentioned that would be a protest wouldn't take very long to check either.

 

[Smokem]

since u say no 35's id assume thata the tire most would run

I've said on more than one occasion maximum 35" tire on 10" rim...

A compromise would be allowing a 265mm dual setup, but a quick calculation would show that it would still have more surface area than a single 315mm setup.

I said nothing about valve size, just the no porting.

Don't take this personally, I'm not singling people out here, just the comments/ideas.

But my question is; how do you plan to tech if the head has been ported in a timely manner?

 

[SmokeShow]

Local WS guys will sling $hit on me next time they see me but I liked watching that video of the itpa 2.5 class where the trucks did NOT have front hanging weights. Has a relatable appeal to the crowd.

The WS here already allows front hanging weight so I doubt they'll nix that w/ the new class.


I'm undecided on the "no duals."

 

[Smokem]

The appeal of no hanging weight visually is there, but it just complicates adding weight and increases the grey area of doing so. Simple, allow hanging weight, no weight boxes.

 

[JMOODY]

Whoever posted the comment about the springs being notched, has no idea how the suspension setup works on pulling trucks. The springs are for the most part cosmetic. They are not carrying any weight.
The dual wheel rule had to be changed in Indiana this year becase the shop that put the rules together built a truck with a dual wheel setup that didn't meet their own rules.
When calling the 2.5 class an entry level class, you can look at what it cost to be competitive and make your own decision:
3,000 turbo
2,500 rods
2,500 heads
5,000 trans and converter
1,000 e locker
1,000 driveshaft
3,000 axles and pinion
500 efi live
1,000 intercooler
1,000 injectors
3,000 dual fuelers
500 fass system
1,500 wheels and tires
1,000 head studs
That puts you at $26,500 and that still not enough to get you a win in central Indiana. I wouldn't be suprised if it wouldn't take 5-10,000 more to get in the top 5. Everybody has a different opinion of what entry level class is.