Warped carb base

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Tom Wilson
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Re: Warped carb base

Post by Tom Wilson »

Timo wrote:I know my replies/writing can appear somewhat harsh at times...
Timo - Your input is always appreciated and taken in the spirit in which it was written. Keep it up, we need your expertise and passion! Next time I head east, I will see if I can drop by the shop and say hello.

I was thinking about the warping and the effect it would have on the bores. Yes it will make them oval, but that oval will not be consistent throughout the length of the bore. All four of my tabs were at different depths, so it would twist the whole carb in a rather uneven way. Now you could make an oval throttle plate that would match when horizontal, but as it turned, it would encounter a different shaped bore, which may result it sticking. For that matter, a round plate would stick as well. That sounds like a bad thing...
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Steve Meltzer
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Re: Warped carb base

Post by Steve Meltzer »

Some great posts here, which draws us (or at least me) to the elephant in the room. Very few of us have the opportunity to drive these cars as they were originally meant to be driven, it's just not practical most of the time. Today's gasoline, with at least 10% ethanol, doesn't help matters any either. So, you try to drive the car when you can, and at least for me, that means more stop and go traffic and less time with my foot in it. As Dyke said, it's when the car is moving from a standing start, or at idle, that is harder on the carb's function and more difficult to get just right, than at WOT. That's when the vacuum is most critical and at it's greatest value. Because I don't get to exercise my cars like I want to, but do drive them quite often, the off idle movement and subsequent return to idle is very, very important to me. If the throttle shafts are "ovaled", the bases warped, or the venturi bores at odds with the butterflies, you can't get the carbs synched nor will they perform appropriately at idle. It's this exact situation that got my carbs to Pierce...I just couldn't get them set right. At high RPMs they were just fine. Unfortunately, these Webers aren't like ubiquitous Holleys, with hundreds of them, some even "correctly dated" on eBay everyday. I've taken all of my Webers completely apart, put in new parts, etc, but when it comes to fixing problems that require more than an "R&R", they're just too valuable for me to experiment on. steve
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Colin Angell
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Re: Warped carb base

Post by Colin Angell »

Hi Timo,

I loved your response and far from having difficulty with English you have exactly articulated what so many of us strive for when you say "I'm always trying to do any/all work to the best of my ability and continually trying to learn ways of doing things better."

I have a friend who says that you can read all the books you like on how to be a downhill skier, but when you buy the boots and skis and go out on the slope the first thing you will do is fall over. There is no substitute for the experience of actually doing something and the same is definitely true of high quality auto mechanics. I think we are all quite passionate about these cars and one of the key elements for me is to be able to personally carry out every aspect of maintenance, repair and restoration myself, without resort to others, no matter how "specialist". I think I got a bit frustrated that what I saw as a fairly straightforward job should get the response of "send it to..... whoever" when Tom was obviously ready to tackle it himself.

Maybe I have been lucky, but I have not had major problems with Webers when able to set them up from scratch and tackle the common problems already described. I have certainly never even thought about reshaping the throttle plates in practice and now regret mentioning it, but the point I was trying to get at was that the shape of the bore probably doesn't matter as long as the throttle plate closes properly.

It is possible to set up these great carburettors to run sweetly and not to stumble when coming off idle, but it takes patience and practice. Best to all, Colin
Timo
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Re: Warped carb base

Post by Timo »

Tom Wilson wrote:
Timo wrote:I know my replies/writing can appear somewhat harsh at times...
Timo - Your input is always appreciated and taken in the spirit in which it was written. Keep it up, we need your expertise and passion! Next time I head east, I will see if I can drop by the shop and say hello.

I was thinking about the warping and the effect it would have on the bores. Yes it will make them oval, but that oval will not be consistent throughout the length of the bore. All four of my tabs were at different depths, so it would twist the whole carb in a rather uneven way. Now you could make an oval throttle plate that would match when horizontal, but as it turned, it would encounter a different shaped bore, which may result it sticking. For that matter, a round plate would stick as well. That sounds like a bad thing...
Tom, thanks for your kind assessment of my sometimes "strongly spirited" posts. Sometimes when attempting to make a strong point I end up allowing too much "passion" and "creativity" to influence my writing and results can be seen as offending, which really is NOT my intention. (Again, another good reason allowing self editing on this site, LOL)
You (or any one else here) is welcomed to visit my humble shop at any time, but I'd like to ask an advance appointment to be made since I don't provide "standard business hours" or "walk-in" access/services.

As for the throttle plates, they technically are oval with edges precision machined to a specific variable angle to accommodate their (angled) fit within what is supposed to be precision machined round bore holes.
Timo
Timo
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Re: Warped carb base

Post by Timo »

Colin Angell wrote:Hi Timo,

I loved your response and far from having difficulty with English you have exactly articulated what so many of us strive for when you say "I'm always trying to do any/all work to the best of my ability and continually trying to learn ways of doing things better."

I have a friend who says that you can read all the books you like on how to be a downhill skier, but when you buy the boots and skis and go out on the slope the first thing you will do is fall over. There is no substitute for the experience of actually doing something and the same is definitely true of high quality auto mechanics. I think we are all quite passionate about these cars and one of the key elements for me is to be able to personally carry out every aspect of maintenance, repair and restoration myself, without resort to others, no matter how "specialist". I think I got a bit frustrated that what I saw as a fairly straightforward job should get the response of "send it to..... whoever" when Tom was obviously ready to tackle it himself.

Maybe I have been lucky, but I have not had major problems with Webers when able to set them up from scratch and tackle the common problems already described. I have certainly never even thought about reshaping the throttle plates in practice and now regret mentioning it, but the point I was trying to get at was that the shape of the bore probably doesn't matter as long as the throttle plate closes properly.

It is possible to set up these great carburettors to run sweetly and not to stumble when coming off idle, but it takes patience and practice. Best to all, Colin
Hi Colin, your kind words are also appreciated.

Couple of extra things (my almost 40 year) "experience" has taught me is that we just can't always do everything ourself, no matter how much we'd like to and yes, there are companies/individuals who are better equipped/experienced in some specialty fields and although sometimes seemingly pricey, their services may end up more cost effective in the grander scheme of things.
Another, though unfortunate lesson experience has taught me, and inadvertently leads me sometimes do more than just shake my head, is the existence of alarming amount of (successful ?) companies/individuals in this "service industry" providing products and services so bad it's beyond comprehension.

And as Mr. Ridgely so aptly pointed out in reference to operation of carburetors in these cars now decades old and many owners/"mechanics" later, current owners/custodians may not even realize how far off they might be.

Cheers,
Timo
Jumprun
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Re: Warped carb base

Post by Jumprun »

I appreciate all the responses. Of course my first instinct it to repair things myself, I guess it is for nearly everyone here, but I can see that it could be costly to practice trial and error on somewhat rare Carbs, 40 DFI /2. and after talking to Mike at Pierce I decided to have him do them....costly? yes, but I figure I do so much of my own work I can afford an expert once in a while. Radiator work is another job for me to send out, even though I have a large precision machine and weld shop facility at my complete disposal, some things are better left to a real expert because the price of failure is too high.
Jumprun
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Re: Warped carb base

Post by Jumprun »

I received my carbs back from Pierce, In addition to repair of the warped bases the bores needed work with new throttle plates. They look good but I'll reserve my final judgement utill I get them bolted on and tuned.
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tinbender
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Re: Warped carb base

Post by tinbender »

How much does this cost?
Regards, Terry Phillips 330GTC #9411
Jumprun
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Re: Warped carb base

Post by Jumprun »

tinbender wrote:How much does this cost?
$3,584 plus shipping. Pierce said they were in pretty bad shape, I thought so too. They now look new and will be the best looking thing on my scruffy car.
Steve Meltzer
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Re: Warped carb base

Post by Steve Meltzer »

I just sent Mike Pierce the last of my Ferrari carbs. The other two sets came out great and both of those cars run dramatically better since he went through the carbs. Heck, I can even synch them and set the idle! Expect to spend several Grover Clevelands, but he's fairly priced, I think, considering the carbs are irreplaceable and the work is top-notch. steve
steve meltzer,
"I've spent all of my money on wine, a beautiful woman, and stunning cars. Then, squandered the rest."
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