POLL: Alternate Crankshaft Pulley???

To Banzai240:

Darin:

Back to the issue of crank shaft pulleys. I neglected to ask in the earlier post, one of the burning questions of the time. Namely, why was the rotary engine allowed the free crank pulley size, when the "boingers" were not?

I mentioned that in the request I made to the Comp. Board to consider the free pulley size (a few years ago). Nothing was mentioned as to the reason for the prejudice (toward the Rotary). I hate inconsistancies!!

Any information?

Thanks,

Bill
 
Originally posted by bill f:
Namely, why was the rotary engine allowed the free crank pulley size, when the "boingers" were not? ... I hate inconsistancies!!

Any information?

Thanks,

Bill
Click to expand...

Bill and others... I don't know the history behind why the rotory gets free pulleys, but I know WHY they need them... Rev one over 6,000 RPM without slowing down the water pump and you'll overheat.

Most of the ITAC sees this as an inconsistency as well, though one could argue that allowing others to "port-match" and not the rotories is likewise inconsistent... but we're split on whether or not this would be "rules creep", or otherwise would be a necessary change for IT. Most of this reluctance seems to revolve around "unintended consequenses" of allowing this change.

I say they would be minimal, if at all... Others believe differently. Overall, the conversation went just like it did here on this site, and ended up deadlocked...

I for one see this as something similiar to the threaded-shock/strut rule... where you are allowed to do something, you just have to do it in the most round-about way possible.
rolleyes.gif


Make sure you all write with some thought-out opinions so we can get this one right, OK?...

------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Renton, WA
ITS '97 240SX
DJ_AV1.jpg


[This message has been edited by Banzai240 (edited May 25, 2004).]
 
Originally posted by Banzai240:
I for one see this as something similiar to the threaded-shock/strut rule... where you are allowed to do something, you just have to do it in the most round-about way possible.
rolleyes.gif
Click to expand...

It comes down the things I mentioned early on. Do you allow free pulleys? Do you require pulleys with integral harmonic damper to remain stock? That one is under serious consideration folks. I know that there are people who are for changing this rule who will not be able to take advantage of it if you are required to retain the stock harmonic damper.

If we allow free pulleys it comes down to whether or not you believe they will increase the performance of the car. Greg says virtually no, I say noticably so. We have experience with the same cars so even folks in the same camp can disagree (and I don't want to rehash with Greg or anyone - I think I've stated the crux clearly and fairly).

FWIW, when we (the ITAC) were discussing it and I again came down against it, someone pointed out it could be the help I'm looking for with my 944. My response was (is) "I know, but I'm still not convinced it's the right thing for IT.

If the membership comes down squarely for it, I will change my position and order pulleys for my car. In the grand scheme of a race car budget, the $350 or so is going to go unnoticed.

My long winded point here is consider carefully all of the issues before you write. If you think the possible unintended consequences are small, OK. If they think they may not be OK. All I ask is that you consider carefully because I'll vote along with member response if it's clearly in favor.

(edit to complete a though I didn't complete initially)

------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

[This message has been edited by Geo (edited May 25, 2004).]
 
Bill and others... I don't know the history behind why the rotory gets free pulleys, but I know WHY they need them... Rev one over 6,000 RPM without slowing down the water pump and you'll overheat.
Click to expand...

I forget the car, and the thread, but wasn't there a request for an item that would essentially do nothing but increase engine longevity. IIRC, the response was that increased engine longevity was considered a 'competitive advantage'. I don't know why, but I thought this was related to the ITB Mustangs. Marcello???

Couldn't giving someone the ability to run the motor over a given rpm w/o overheating be considered the same kind of thing? Not trying to alienate the rotory folks, just trying to get to how it's good for IT when we have some rules that only apply to certain cars. And I know, here comes the porting rule for the rotaries. Different animal.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608
 
Originally posted by Bill Miller:
And I know, here comes the porting rule for the rotaries. Different animal.
Click to expand...

Why? I'm not being flip. Perhaps there is something I haven't considered. I don't know Wankels that well.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com
 
good point george, allow the same rules for all engines and maybe the talk of moving the 7's to ITB would end although my experimentation with port matching stock rotarys was at best volatile with minute gains without opening the exhaust ports. I still think I must have done something wrong.
 
Originally posted by Bill Miller:
Couldn't giving someone the ability to run the motor over a given rpm w/o overheating be considered the same kind of thing? Not trying to alienate the rotory folks, ...... And I know, here comes the porting rule for the rotaries. Different animal.
Click to expand...

Good point. The ITA class HAS become known as the "Better have an RX-7" class lately....
rolleyes.gif


Look, the original guys who classed the car did so with the knowledge of the pulley issue, and set the weight accordingly. Changing the rule post classification is a dumb idea. You do remember th ECU rule, right? Only ths time the RX-7 would slink even lower in the results....



------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]
 
Originally posted by lateapex911:
Only ths time the RX-7 would slink even lower in the results....
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I'm growing increasingly weary of hearing of the plights of the poor old RX-7... Sorry guys... but why does EVERY rule discussion for EVERY class that car has ever been in always end up revolving around whether or not the topic is good for the RX-7????

Yes, there are a lot of them out there, and yes, they are fun, cheap cars to race, but enough already! There are at least 3 different IT-ish classes in just about every Region where the RX-7 can enjoy good competition... Why do we always have to build are rules around what is or isn't good for THESE cars??? THERE ARE other cars out there to consider, you know...

...
...
...

OK, sorry guys... it's been a long day...



------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Renton, WA
ITS '97 240SX
DJ_AV1.jpg
 
Originally posted by Banzai240:
There are at least 3 different IT-ish classes in just about every Region where the RX-7 can enjoy good competition...
OK, sorry guys... it's been a long day...
Click to expand...

Uh darin, I am sorry about the long day, but i assume you are refering to IT7 and Spec7 and well as ITA. If so the former 2 classes are not GCR classes and are avaialble in all areas. we have neither in the northeast. I really don't want the Comp board saying that a particilar car does not matter because it can always go run a spec class. Spec classes are more a sign that we have not solved the problem than a solution.
dick patullo
ner scca
 
Originally posted by dickita15:
I really don't want the Comp board saying that a particilar car does not matter because it can always go run a spec class. Spec classes are more a sign that we have not solved the problem than a solution.
Click to expand...

Agreed.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com
 
Originally posted by Banzai240:
I'm growing increasingly weary of hearing of the plights of the poor old RX-7... Sorry guys... but why does EVERY rule discussion for EVERY class that car has ever been in always end up revolving around whether or not the topic is good for the RX-7????

Yes, there are a lot of them out there, and yes, they are fun, cheap cars to race, but enough already! There are at least 3 different IT-ish classes in just about every Region where the RX-7 can enjoy good competition... Why do we always have to build are rules around what is or isn't good for THESE cars??? THERE ARE other cars out there to consider, you know...

...
...
...

OK, sorry guys... it's been a long day...
Click to expand...

First, I didn't bring it up.

Second, I used it to make a point, which was completely ignored. The point being that after-the-classification rules changes are a bad thing in general, and must be made very carefully.

Finally, I have tried, from the start of my posting and comments, to use the plight of the RX-7 as a banner carrier for the rest of the cars in the same boat. It just happens that the RX-7 is the best example of the situation, and as I have raced and developed one, I feel qualified to comment.

I'm sorry if my comments come across as self centered, or complaining about the "plight" of the 7.

And BTW, the only time I have had the chance to race in anything other than ITA was at the end of a 1200 mile tow at the ARRCs.

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

[This message has been edited by lateapex911 (edited May 26, 2004).]
 
Originally posted by Bill Miller:
Couldn't giving someone the ability to run the motor over a given rpm w/o overheating be considered the same kind of thing? Not trying to alienate the rotory folks, just trying to get to how it's good for IT when we have some rules that only apply to certain cars.
Click to expand...

My vote flip flopped during the call. I am very much against any car-specific rules and this is one but I do feel it needs to be grandfathered in. In this case, if you don't 'allow' rotories to rev past 6000, you kill the cars.

According to my dyno sheet in front of me, I loose 14% of my horsepower (S5 13B) if limited to 6K.

I think adding the rule for the class is creep - and killing it for the rotories is going two steps back for one step forward. No current rotory is an overdog in any class so it doesn't create equity to make the move while it undoes any semblence of current parity. Ya, I know, not guaranteed but it should be a consideration, IMHO.

AB

------------------
Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region
www.flatout-motorsports.com
 
Andy,

I'm not saying that it should be taken away from the wankers, err, I mean Wankels, yeah, that's it!!
biggrin.gif


Really, I don't think it should be taken away. But, how many times have peoples' requests at relief been met w/ "Hey, you should have done your homework before you picked the car."

Hey, there's a thought. Take the free crank pulley away from the 12A crowd, and move them to ITB! <ducks quickly>

I think you know that my main gripe is the lack of internal consitency w/in the rules. This is just another example.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608
 
Originally posted by Bill Miller:
Andy,


Hey, there's a thought. Take the free crank pulley away from the 12A crowd, and move them to ITB! <ducks quickly>

I think you know that my main gripe is the lack of internal consitency w/in the rules. This is just another example.
Click to expand...
That is a really old rule, but I think it went hand in hand with the original classification, so its ok.

However, if you are willing to move us 12A-ers to B, I would gladdly give you my crnk pulley. And my 7" rims. And 60 pounds.



------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]
 
Boingers vs Rotaries...If memmory serves, part of the intake opening into the rotary chambers is less than 1 inch from the gasket surface. That means port matching to 1" from the gasket surface would translate to bridgeporting a rotary. As a rotary racer (and my own engine builder), I don't want to screw with the porting...I support the no port matching on rotaries.
In terms of crank and water pump pullies, I don't know the history, but I suspect it's it's part of the displacement equivelency give and take.
Last, as for moving rx-7 to ITB and taking away pully's as a competition adjustment...remember that means we cant operate CONTINUOUSLY above 6k. We could still make occaisional bursts to high rev's. Like at starts and when passing people! It would be just like Nitrous! That is not a good competition adjustment.

Tak
#29 ITA
SFR SCCA
 
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