how many out there are building 2.5 trucks

Yes...some organizations have issues with running a work stock class and a street class if you will ... Agree with your comments
 
Teamfreeman04 said:
Same as I have read , but I find it interesting that no one questions programmers in this class...somewhat quick hp....lolo...and in today's market they give you a lot of options inside programmer, fuel deliver, timing advancement and ect
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Yes but they allow folks to adjust timing and fuel on all of the trucks as well.

I had forgotten that individual runners weren't allowed in the 2.5 and I agree with that rule.

Start with tight rules and if need allow a little more.
 
zstroken said:
Yes but they allow folks to adjust timing and fuel on all of the trucks as well.

I had forgotten that individual runners weren't allowed in the 2.5 and I agree with that rule.

Start with tight rules and if need allow a little more.
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What about the bb tooling style intake? Thoughts
 
I don't have much input on this since I have not built a motor.. Yet!

But I think rules should be limited to:
A true 2.5 charger, no clipped wheels
No header style exhaust manifolds, steed speed included, T4 at most
Stock intake runner
Stock appearing pumps, no dual CP3s and no 13 mm pumps
Single rear wheel only

I was against the single rear wheel at first for all the dually owners. But you can always just put a single rear wheel on a dual rear wheel axle, easily. Or maybe the rule be unlimited width single rear wheel and only a certain size max dual rear wheel.

That would be a decent HP power class. Would be good for the guys that want a hot rod but can't afford a 2.6. And gives the guys with a workstock truck trying their bad at pulling a fair chance, doesn't scare them off.
 
RockinRam96 said:
I don't have much input on this since I have not built a motor.. Yet!

But I think rules should be limited to:
A true 2.5 charger, no clipped wheels
No header style exhaust manifolds, steed speed included, T4 at most
Stock intake runner
Stock appearing pumps, no dual CP3s and no 13 mm pumps
Single rear wheel only

I was against the single rear wheel at first for all the dually owners. But you can always just put a single rear wheel on a dual rear wheel axle, easily. Or maybe the rule be unlimited width single rear wheel and only a certain size max dual rear wheel.

That would be a decent HP power class. Would be good for the guys that want a hot rod but can't afford a 2.6. And gives the guys with a workstock truck trying their bad at pulling a fair chance, doesn't scare them off.
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How will you tech a 13mm pump?
I don't see an issue with Dual cp3's. Folks will just go out and spend big bucks on a modded cp3.

It appears the existing 2.5 rules are on the right track, not a need to rewrite them.
 
zstroken said:
What turbo rules do you suggest?
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Straight bore. No custom wheels or covers. A true 2.5 bore turbo. You can only take in so much air. Regulate the mwe grove and be done. Make it so there is no grey and if someone try's messing with the grey there dq'd
 
97rada said:
Straight bore. No custom wheels or covers. A true 2.5 bore turbo. You can only take in so much air. Regulate the mwe grove and be done. Make it so there is no grey and if someone try's messing with the grey there dq'd
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Thought the rules said straight 2.5 bore...
Also thought the current 2.5 rules utilize a width limited MWE...

What did I miss?
 
zstroken said:
How will you tech a 13mm pump?
I don't see an issue with Dual cp3's. Folks will just go out and spend big bucks on a modded cp3.

It appears the existing 2.5 rules are on the right track, not a need to rewrite them.
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You don't think there is a turbo issue?
 
97rada said:
You don't think there is a turbo issue?
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S-4 Turbo is the largest turbo allowed. Turbo must be a true 2.5 charger. No clipped wheels or stepdown covers. ¼ inch MWE groove maximum. Inducer bor
e must be non- removable. All air must go
through 2.5 inducer bore or MWE groove. The wheel m
ust protrude into the 2.5 bore 1/8”. Turbo will be
checked with a 2.550” plug. The driver will be resp
onsible for making compressor wheel and bore
accessible for tech officials to measure bore and i
nspect compressor wheel


Straight from ITPA's website. What are you suggesting is the issue? Several other orgs are saying t4 foot is the largest.
 
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Hmm, so it doesn't say how long the bore has to maintain 2.55" ahead of the wheel like how the 2.6 rules say 3/4" length?

I believe nixing the mwe altogether would pull back on the ol' reigns too.


I still think a restrictor orifice tube might be good for the 2.5 class (or any turbo-limited class really). Then the teching of turbos becomes much less of an issue wouldn't it??? You could run a big charger but there's only so much sucking through an orifice it can do, right?? So it won't matter, right??
 
IMO the horsepower gain isn't coming from grey areas in the turbo rules, it's just coming from technology advancement. Look at how far 2.6 has come in the last few years. I remember back when I was in HS and a real 2.6 truck could still be driven on the street
 
I think that no a/w intercoolers and straight bore turbo will keep this from getting out of hand. These are the 2 main areas where 2.6 went wrong if you ask me. I see 2.5 being the new 2.6 and 2.6 fading out. I can think of at least 4 or 5 guys the last 2 years that made the jump from 2.6 to 3.0 and like I keep saying, as technology advances then more and more ring and pinions and driveline parts and going to go boom until people just get sick of replacing them and drop the coin on a big rearend and ODL setup. Also, why is there never any mention of a 63.5mm compressor wheel in 2.5? Correct me if I'm wrong but couldn't that end a lot of this confusion and grey area talk?
 
SmokeShow said:
Hmm, so it doesn't say how long the bore has to maintain 2.55" ahead of the wheel like how the 2.6 rules say 3/4" length?
I believe nixing the mwe altogether would pull back on the ol' reigns too.


I still think a restrictor orifice tube might be good for the 2.5 class (or any turbo-limited class really). Then the teching of turbos becomes much less of an issue wouldn't it??? You could run a big charger but there's only so much sucking through an orifice it can do, right?? So it won't matter, right??
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When you start talking about bore length, and inducer protrusion, now MWE groove, you start pushing farther and farther into custom turbo territory. You can not purchase a box stock S463 that will meet ITPA rules. The bore tolerance is to lose in most cases, and there would not be enough inducer bore for 1/8" protrusion, and 3/4" bore, without a slug...

The 1/8" protrusion rule on fixed 2.5" bore is crazy enough as it is, because it DQ's nearly every Holset style wheel out there, including a stock HE351. Just to keep our guys legal for ITPA, we have to bore and slug every cover, to be sure they will pass a 2.55" tech.

Right now, it seems that class is going well. And more importantly from a promoting stand point, its a fun class to watch. Hopefully it will continue to grow, and get more on a national scale, like the Indidana Diesel Shootout this past weekend.

Caleb
 
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