Stock IT7 Carbs

[sam3481]

Hey I was hoping to get a poll as to see whos carbs do this thing I got DQ'ed for. Go check out your street car or your race car as long as the throttle linkage hasent been tampered with and pull the throttle wide open. Take a look down the secondaries and see if they move at all. If they even budge any let me know just curious.
Thanks every one
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Sam Collier III
#93 Yellow IT7

[Hotshoe]

Sorry to hear about the problem in tech. I have had this problem but I fixed it (for good) about four years ago. Cost me about one dollar. I took and adjusted all the linkage so that everything did as it should. Then I made a cable stop by cutting a 10mm bolt with a die grinder and a cut-off wheel from the bottom up to the base of the head length wise. Place that over the cable at the point where the cable enters the housing. Open the throttle to wide open and tighten the stop. This way the only time the factory stop on the carb gets stressed is when it goes to tech.
And one other thing...Do not change or take the spring out of the vacume actuator for the secondaries. That will also cause problems.
I know this is a little more than you asked for but I thought you would like to know how to keep it from happening again. The factory throttle stop on the gas pedal just isn't strong enough to handle what we put it through.

Rick Thompson
#99 IT7

[steve s]

my secondaries doesn't even move.on all my cars.bending the linkage is a great trick .i was caught and that problem hasbeen solved a long time ago.

[balz]

I had a stock carb with me and brought it up to tech for Sam H. and Brian D. to look at. The secondaries didn't more when you advanced the throttle..HOWEVER...I didn't do the test the same way that the Tech inspectors did. I understand that they flipped the carb upside down and ran the test. It could have had a difference on how the outcome if I would have done the same thing. I checked my carb on the car and thank god...no movement.



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Balz
#67 IT-7
www.balz.myip.org
"I live my life one Apex (seal) at a time"

[moto62]

. Take a look down the secondaries and see if they move at all. If they even budge any let me know just curious.
Thanks every one
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Sam Collier III
#93 Yellow IT7[/B][/QUOTE]

Hey Sam! I did what you requested on a carb that is sitting on a motor in the garage. This is a virgin carb that has never been tampered with by any gurus. Whoala!! The secondaries did not even budge, which brings up an interesting thought. I know the secondaries in the carb on the the race car does flip open about a two degree sweep at full throttle. Every other carb that I've seen, or rebuilt, does the same thing. The little U linkage attached to the butterfly rod on a certain year carb is actually different and can give you oh...four to five degs of sweep. I actually thought these carbs were designed that way. Oh well, I guess it's back to the drawing board, And for all my fellow competitors, I apologise for having those couple o xtra horses, but I'm not giving back any trophies http://Forums.ImprovedTouring.com/it/biggrin.gif
Ray
moto62
NERSCCA

[sam3481]

Moto62
Thanks man I really apreciate it. I was wondering if I was the only person. At least I know that its not a fluke. I dident tamper with my carb to intentonally make it do that but thats how it goes i guess. I will make sure its never a problem again. Ehh well the good thing is that when this problem was brought to my attention we noticed that the secondaries were going past 90degrees which made them start to close again(less power). Soo that is a good thing. If any one else has time to do this little test let me know of your results.
Thanks
Sam Collier III
#93 Yellow IT7

[lateapex911]

Originally posted by sam3481:

......good thing is that when this problem was brought to my attention we noticed that the secondaries were going past 90degrees which made them start to close again(less power). Soo that is a good thing. If any one else has time to do this little test let me know of your results.
Thanks
Sam Collier III
#93 Yellow IT7

Well Sam, it's 35 degrees and raining here, but I ran out and pulled the (wet) cover off the car and checked with a flashlight, and I couldn't see the operation as you described. You mean primaries right??

I'll check more closely when the environment is better!

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

[This message has been edited by lateapex911 (edited November 13, 2002).]

[lateapex911]

Hey Sam! I did what you requested on a carb that is sitting on a motor in the garage. This is a virgin carb that has never been tampered with by any gurus. Whoala!! The secondaries did not even budge, which brings up an interesting thought. I know the secondaries in the carb on the the race car does flip open about a two degree sweep at full throttle. Every other carb that I've seen, or rebuilt, does the same thing. The little U linkage attached to the butterfly rod on a certain year carb is actually different and can give you oh...four to five degs of sweep. I actually thought these carbs were designed that way. Oh well, I guess it's back to the drawing board, And for all my fellow competitors, I apologise for having those couple o xtra horses, but I'm not giving back any trophies http://Forums.ImprovedTouring.com/it/biggrin.gif
Ray
moto62
NERSCCA[/B]

AHA!!!!!!

Now I know why you were soooooooooo fast!

Can't wait 'til next year when we are on equal footing!

Well, at least you're man enough to admit it!

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

[This message has been edited by lateapex911 (edited November 13, 2002).]

[moto62]

Originally posted by lateapex911:[/b]

Can't wait 'til next year when we are on equal footing!
Jake,Jake,Jake,
Not so fast sonny. I guess now I'll have to take off the cooling fan to regain those few horses that I'm giving up http://Forums.ImprovedTouring.com/it/wink.gif
Ray/Rmoto

[/B]

[dpc]

Ray, Iam not worried about your carb, but make sure your ballast is in the right place. I promisee not to use you for a guardrail next season???????. dave

[sam3481]

Yea I ment to say primaries. Well I dont know some peoples carbs do it and some peoples carbs dont. It was just plain bad luck for me and Brian Dobbs. Any way if any one else gets the urge go take a look at your carb and tell us what you see. Thanks
Sam Collier III
#93 Yellow IT7

[Dave Damouth]

Spare stock carb and a prepped carb I have both do it, by a few thousands. Appears to be caused by flexing of the primary shaft if you put enough pressure on the bellcrank. I believe that it would only happen if operated by hand, and the cable adjustment & throttle stop would prevent it from occuring when the carb was operated normally. Didn't have a spare body to stomp on the pedal and see. I would maintain that it could occur in any carb if enough pressure was put on the bellcrank, so it depends how hard the individual pushes and how much the shaft has been previously flexed by over travelling. For those who don't see this phenomenom, how hard are you pushing on the bellcrank? Or are you operating it via cable?

Sam, how much of a throttle movement are you talking about? I haven't measured it yet, but I'll ballpark mine at .010", with probably 15 to 20 lbs pressure on the tang at the outermost part of the primary bellcrank.