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jimwheeler
10-17-2006, 05:43 PM
I just re-read the rule on carburetor's and have to admit the tech shed was right. "Other than as provided for in these rules, the carburetor shall not be modified in any way."
It does list the items that may be modified and the accelerator pump is not listed as an item that can be changed.
Jim Wheeler

KEVIN LANGSTON
10-17-2006, 06:05 PM
I HAVE BOUGHT APROX 8 4776 CARBS NEW FROM HOLLEY OVER THE LAST 10 YEARS. I HAVE RECEIVED THEM FROM HOLLEY WITH BOTH 30CC AND 50 CC ACCELLERATOR PUMPS. WHEN I SAW THE DIFFERENCE I HAD CONTACTED THEM AND INQUIRED ABOUT THE DIFFERENCE. I WAS TOLD DIRECT FROM HOLLY TECH THE SOMETIMES THE RUN OUT OF PARTS AND INSTEAD OF SHELVING THE UNITS AND WAITING FOR THE 30 CC PUMPS THEY HAD INDEED PUT 50 CC PUMPS ON THESE MODELS. THEY HAVE INDEED MADE THESE CARBS BOTH WAYS. THERE IS NO SPEC PAGE I HAVE FOUND FOR THESE CARBS THE SPECIFYS JUST THE 30CC PUMP. WHERE DID THE TECH SHED GET THERE INFO?? I HAVE WORKED IN THE TECH TRAILER MANY YEARS.IN THAT TIME I SAW 50 CC PUMPS PASSED AND NEVER QUESTIONED.DONT UNDERSTAND WHERE THIS WAS DECIDEDAND AND HOW SO MANY THINGS CHANGE FROM YEAR TO YEAR. LEGAL LAST YEAR AND ILLEAGLE THIS YEAR WITH NO RULE CHANGES. MAYBE NEW PEOPLE THERE THAT NO VERY LITTLE ABOUT THE CLASS AND ITS RULES DOING THE TECH THIS YEAR. JUST MY FYI TO ALL. :cheers:

jimwheeler
10-17-2006, 06:14 PM
Kevin,
I have three holly carbs and they all have the 30 cc pumps. What you have said is very distressing. If the carb came from holly that way, then, hell, I don't know what to make of the whole thing.
Jim

23CRLmotorsports
10-17-2006, 06:16 PM
I too have ordered a carb from summit and it came with the 50cc on it , we changed it to the 30cc for tuning issues anyways, and I was un aware you couldnt change that for tuning purposes, everything Ive ever seen says to tune the carb with jets power valves and acc pumps..... hopefully they overturn that DQ and he gets his win

t4wallace
10-17-2006, 06:38 PM
I too have ordered a carb from summit and it came with the 50cc on it , we changed it to the 30cc for tuning issues anyways, and I was un aware you couldnt change that for tuning purposes, everything Ive ever seen says to tune the carb with jets power valves and acc pumps..... hopefully they overturn that DQ and he gets his win
While we could hope for this to happen (especially if in Mike's shoes), we all know that it's balmy and 110 in hell right now with no signs of a cool front any time soon.

A. Can we get Holley to officially support that both pumps were installed from the factory on 4776 carbs?
B. If that can happen, can it then be sent into SCCA so, at minimum, this is on record and no one else has to go through what Mike did? Assuming we have no prayer of that cold front coming.

This is making me ill.

Mike Lavigne
10-17-2006, 06:38 PM
Man I'm sick. They said they called Holley and ask if the carb was built that way and was told that it was not. I spent Sunday morning trying to find evidence (Time allowed) to talk to people but no one was open. I then called the same person that tech did and spoke with him,he assured me that they don't put 50cc pumps on 600. I ask him if he was sure he said that maybe if he look at archives on Monday that mayby there was that he didn't know about. He said he would talk to SCCA on the phone to tell them what he knew and there was probably no competition advantage but truly a tuning process. SCCA said they weren't concerned with the advantage but rather that it was not stock.END OF STORY JH WINS
MIKE
42AS

CMP FAB
10-17-2006, 08:19 PM
This is ridiculous. It makes me want to puke. I agree with Kevin in that of the 30 or so carbs that I have bought in the last few years (not just 4776's) it has been a crapshoot as to what pumps they show up with.

The pump shot is part of tuning the fuel curve to meet a particular engine's characteristics and use. Changing that is no different than changing a metering block or power valve. The rule does not state that the carb has to be "box stock," it states that it cannot be modified. Bolting on a direct Holley replacement part is not a modification. Per the GCR, page 146 -

"MODIFY - To change a component by reworking, but not by replacing."

The intent of the rule is to stop us from reworking the venturi area to make the carb flow more air, not to limit how we tune the engine with the air flow that is available.

This is what is wrong with this class, and the SCCA in general. The intent of rules and the bigger picture is thrown aside to satisfy other agendas.

Bill Richter
10-17-2006, 10:17 PM
I am really glad that I read this thread. I have yet to place my "carb order".

http://i8.www.photobucket.com/albums/a44/racer_/holley600.jpg

I was just gonna' go on-line with Summit, and take my chances. Is there a place to buy a "faster" 4776?:confused:

Bill

.

23CRLmotorsports
10-18-2006, 03:59 PM
they gotta make Jh win something one way or another

jfaphoenix32
10-18-2006, 04:19 PM
We just checked our records and Tom has purchased approximately 22 Holly Carbs over the years for himself or his customers...

Not a single one had a 50 cc accelerator pump.

How do we get one that has it? Who makes the 50CC pump? REO?

We can put it on an engine on our engine dyno, and measure what kind of power difference it makes, if any...

Joe

King Matt
10-18-2006, 04:39 PM
I currently have about a dozen new Holleys in my shop, and I've handled at least 50 more brand-new ones over the past 10 years, and I've never seen one come new with a 50cc pump. But the language quoted out of the GCRs defining "modify" is far more troubling than the possibility of a factory error. I hope there is some way to appeal that DQ.

The 50cc pump housings are still available from Holley, but I usually only see them on tunnel rams, or guys who want to dump more fuel into the motor when they accelerate off a corner.

t4wallace
10-18-2006, 04:56 PM
In the end this is simple. The carb on Mike's car was not compliant, based what SCCA and Holley say is "standard equipment" on the 4776. John's car was found to be compliant for the 4th year in a row. So it's not like the Firebird hasn't been looked over. There might be a lesson in there.
they gotta make Jh win something one way or another
Tom and Joe (and their folks) are good people that prep good cars. They have been nothing but complimentary to us. To associate what we (as racers) think about John and his racing in AS with what Phoenix and TAR do would not be fair.

smithpr
10-18-2006, 05:46 PM
I am very confused. Something is really wrong.

I have a fairly nice Data system in my car that also includes an O2 sensor. I also have a throttle position sensor. This allows me to track in detail the fuel mixture based on throttle position ever lap of every race. I run a 30cc pump and based on the data the last thing my car needs is a bigger accel pump. The car goes very rich every time the loud peddle is pushed. I have been working to take pump action out of the car. I run a fair amount of play in the pump to try to keep the A/F close.

If the Fords need the big pump for tuning they must make even more power then I thought. I need about a 20cc pump. I could be just way down on power so my car just doesn't use the same amount of air that Mike's does. I guess I just need the small pump to go with the very little air that my engine uses and therefore the small amount of power that my engine must be making compared with the Fords.

Philip

CMP FAB
10-18-2006, 08:48 PM
Whether or not the 50cc pump ever came stock on a 4776 is a moot point. The whole point is that the rules DO NOT SAY "BOX STOCK" but say that the carb shall not be MODIFIED in any way other than as provided in the rules. The two modifications provided in the rules is the aligning of venturis, and the drilling of holes in the throttle plates.

Yes, it does say that power valves, metering blocks and floats may be ALTERED. It does not state anything about the REPLACING of accel pumps for tuning purposes.

Again, from the GCR, page 131 -

ALTER - to change a component by MODIFYING

MODIFY - (page 146) to change a component by reworking, but NOT by REPLACING.

So if I REPLACE a Holley 30CC pump with a Holley 50CC pump that bolts directly on, it's illegal? I have had need for this before due to tracks that have a lot of on gas/off gas/back on gas areas. The 30cc pump can fall short because of the fast cycling of the pedal, not allowing it to keep up with the fuel demands. Plus some engines just love a fat pump shot to get em going!

So, if a 50cc pump is illegal, is changing the pump cam and the pump shooter illegal too? Gosh, there are 4 different fuel circuits (idle, pump, main jet and power valve) on a Holley, and the rules only touch on 3 of them! Is my 30cc holley going to get DQ'ed because I put in a pink pump cam instead of the orange one that it came with?????

It's all part of carb tuning, for crying out loud! If the venturi's fit the gauge, it should all be legal!

This is micro-management of the rules. This is judging parts to be illegal upon things which no rule was written about. The guys who wrote the rule obviously didn't know that a Holley has 4 fuel circuits, (hey, does anyone want to discuss air bleeds?) and this is the crap that we have to deal with.

Good rule sets are usually very short and sweet. The more rules there are to "clarify" things, the more gray areas show up and the more controversy. I think that AS should look at simplifying the rules and opening things up a little. I know that people will cry "that's more money!" but racing is not about money. There are always people who will race in the same class trying to spend as little as possible, and the ones who will spend like there is no tomorrow. That is just the way it is.

The DQ was bull puckey.

Mark Allen
10-19-2006, 07:27 AM
Mitch has a great point. Not many people have changed their Accel Pumps but I'll bet a ton of AS guys have bought the holley "pump cam" kit with the little multi colored plastic cams. Since the Holley's come out of the box so rich I'll bet most people have at least tried running leaner cams. Based on the interpretation in the tech shed this may now be illegal simply because they don't expressly say that we can change them (like they say that we can remove the choke). Could be scary.

Mark

thomas toth
10-19-2006, 12:03 PM
Don't have the book with me but doesn't it say linkage may be changed. The little colored cams are part of the linkage.

Tom

23CRLmotorsports
10-19-2006, 04:51 PM
holley makes the acc pump, evey 50cc I had was pulled because it was too much fuel its pretty common on bigger motors bigger carbs but as far as i know shouldnt help the AS motor combo its to big a shot of fuel but I could be wrong. anyways ohwell Im sure the ruling is set in stone now, Dont you only have a few days or hours to protest and file all the info? next year mike

KW78
10-19-2006, 05:52 PM
I am very confused. Something is really wrong.

.....

If the Fords need the big pump for tuning they must make even more power then I thought. I need about a 20cc pump. I could be just way down on power so my car just doesn't use the same amount of air that Mike's does. I guess I just need the small pump to go with the very little air that my engine uses and therefore the small amount of power that my engine must be making compared with the Fords.

Philip

:clap: :clap: :clap: :clap:

You really should run for political office! My corresponding argument would be that:

No, the fact that the Camaro doesn't need a pump shot means that the vacuum signal from the combustion chamber to the underside of the throttle plates is so, so, crisp, that you have instant throttle response and max torque under all conditions. No wonder mustangs need more power, you chevy guys had all the parts designs lined up for this perfect scenario and can put max torque down the instant the driver starts to formulate the thought of forward acceleration. ...

Of course both arguments are rubbish because we all know that the pump shot is a transition circuit to compensate for the big gulp of air that makes it by the venturis when the throttle is opened but the fuel is not sucked up through the venturis yet, causing a big hesitation for some part of a second at low engine speeds... Don't we all know that, Philip??? So above something like 3Krpm, it is just a nuisance to stabilizing fuel mixtures. (Which is why i have <<illegally>> put a small nozzle and small cam on the carb and have almost no volume).

Nice try though ! :cheers:

Kyle

KW78
10-28-2006, 11:33 PM
Speaking of big sucking noises, how 'bout those Tigers.

Congrats Philip on your Cards, but that probably used up all your chevy favors/karma ! :clap: