air horns for sidedraft carb

[Crusher]

Its time for 20 questions....
How do the air horns for sidedraft Webers affect the performance ?.
And does the shape and length of the horn affect airflow ?
Is there air filter that will fit inside a horn ?

Steve

[GTJIM]

1) They smooth the air flow and contain flow reversion pulses thus stabilising the airflow and enhancing performance
2) The shape is fairly critical as they must be formed to let the air flow follow the inner curve. Length alters the inlet tract length and moves the "tuning" rev range of the carb system. Longer - lower rev range. Shorter - higher rev range.
3) There are meshes that fit inside the horns or across the front of the trumpet but they lower the air flow and the better question is: "Are there filters that the air horns fit inside .....

4) Next 17 questions........

[Crusher]

So is there an optimum horn length ?

[kwilford]

As one of more senior members just mentioned to me in a Moderator Report:

"I realize this guy is new to the forums, but perhaps someone could let him know to search the forums first for his questions (since they've been covered many times before). Also, I noticed he seems to post everything in the 'open discussion' forum."

As the aforementioned senior member suggests, the Search function does indeed show up a NUMBER of relevant threads:

http://www.opelgt.com/forums/search.php?searchid=58747

And as he also mentions, please see if there is an appropriate Forum heading to start a thread in. I had already moved this to the "Aftermarket Side-draft carbs" Forum.

Moderating is SO much easier when everybody helps out. Thanks!

[Crusher]

So sorry I ruffled your feathers.
Yes, I am new to this website and am not up on the Opelgt.com ediquet, I'll try your suggestion. Thanks.

Oh, It would be nice if you would direct the tread to me directly, instead of getting someone else to to "Tell This Guy" how to do things.

[hrcollinsjr]

Steve, please reread Keith's statement about "someone tell this guy". It is a quote from someone else, not Keith's words.

And I really doubt you ruffled anyone's feather's.

Harold

[kwilford]

Steve, please reread Keith's statement about "someone tell this guy". It is a quote from someone else, not Keith's words.
And I really doubt you ruffled anyone's feather's.
Harold

Quite so, Harold, my feathers are entirely unruffled. I was merely "killing two birds" (ah, DEFINITELY pun intended! ) by mentioning the power of the search function (and demonstrating how well it works) while also pointing out the value of posting in a Forum that is related to the topic. It makes future searches for answers so much easier.

Sometimes I do send a PM directly to a new member to help him or her with some of the site etiquette. But with over 5000 members, I simply don't have time to PM each new member.

While I am at it, please also feel free to add to an existing related thread that you find in the search if it doesn't fully answer your question. The real power of this site is that questions get answered, and the more fully they get answered, the better this site is.

HTH

[Crusher]

I'll try using the search function in the future instead of bringing up old issues.
This Website has a wealth of information and I hope I can add to it.
sorry for being short...in the earlier thread.

Steve

[nobody]

Air horns, yes they come in alot of variations. Picture is of a new set from Gabiele out of Italy. 13 each and 6 dollars shipping.

http://www.opelgt.com/forums/attachm...achmentid=3758

[davegt27]

Steve -- try to get the Book How to build Horsepower vol. 2 by David Vizard.

It has real good info on Carbs and Air horns.


HTH
Davegt27

[Crusher]

Thanks all,
Looks like I'm going to do a couple minor changes to my intake.

Steve

[GTJIM]

Oh, It would be nice if you would direct the tread to me directly, instead of getting someone else to to "Tell This Guy" how to do things.

I was enjoying answering your questions, Crusher! Sometimes I learn stuff too when searching for the answers. Keep asking those questions.......
Regards,

[Paul]

Steve,

You asked a question that most everyone would ask, Is there an optimum Length for the air horn. As you may have guessed by now, there is NO simple answer to your question. The Optimum Length of the air horns, as stated earlier, is not only RPM related but dependant upon any modification you may have already made or would like to make.

Some of the answers you desire will be found by reading "between the lines" of other posts.

There are equations to calculate intake track length, sometimes trial and error is easier. But as Jim said, longer gives better low end and shorter gives more RPM. In some of the threads, exact length may have been listed. But that info will only be usefull if you know their engine modifications.

However, someone one maybe able to give a good recommendation based upon their personal experience.

Good luck in your research.

[Crusher]

I've been doing allot of research on exhaust and intake manafolds the last couple days....On the intake side, your right according to everything i've found, but it only helps in a very short rpm range...yes, it would take to long to explain it but I now understand whats going on.

Now on the other hand, the exhaust at this point would probably give me more boost in performance than messing around with the horns.

[Paul]

It just depends upon any other mods you've made. If you've made lots of improvements to the Intake side, then you could see gains from exhaust improvements. Its a balancing act.

In your research, you should check out www.headerdesign.com

Lots of good reading!