Carburators at altitude

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Momboy007
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Joined: Fri Apr 01, 2016 6:56 pm

Carburators at altitude

Post by Momboy007 »

Hello All,
I plan on attending the Big Bear Bash this year in my little buggy, will I have any trouble at that altitude with the motor?

Thanks,

Rick
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jsturtlebuggy
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Re: Carburators at altitude

Post by jsturtlebuggy »

Tell us what you have for an engine and what kind of carburation you have. And at what elevation are you at now?
Joseph
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Having fun with Buggies since 1970
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Momboy007
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Re: Carburators at altitude

Post by Momboy007 »

Hello All,
I know it has a 1600 tp with a 009 Distributor, looks like a stock carburetor and was jetted for valley center Ca. altitude (Maybe 2500 feet in elevation)

It is Nate's old Glitterbug from Turnkey Manx

Thanks,

Rick
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jsturtlebuggy
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Re: Carburators at altitude

Post by jsturtlebuggy »

Should run fine at Big Bear if it not running overly rich now where you live.
Joseph
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Having fun with Buggies since 1970
Worked in VWs in shops since 1970
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Mike-Presley
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Location: Barstow, Calif.

Re: Carburators at altitude

Post by Mike-Presley »

I agree that you should be fine at Big Bear. I am planning on going higher at Ouray/Silverton later this year and got this info from the guys on the RBC site.
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5150bossman
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Re: Carburators at altitude

Post by 5150bossman »

The lake itself is around 6800' altitude. At that altitude, our 1776 with a single Weber 40 runs like a dog (no power, and lots of hesitation). I re-jet our carb for 7000' and then it runs much smoother, though it still lacks the power it has at sea level. Re-jetting this way allows me to run down the mountain to 4000' or up to the summit over 9000' without a problem. Some people just advance the timing a bit to adjust for the higher altitude, but you would have to ask them about that.

Here's a link to some Weber carb tips (sorry, I don't have anything for a stock Solex.).

http://www.racetep.com/webtechpage.html
Momboy007
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Re: Carburators at altitude

Post by Momboy007 »

Hello All,

I took up to our cabin in Big Bear for the first time this Weekend, also my first out in the buggy, it runs way too rich, In fact my wife said to take her home because it smelled so badly of gas.
I checked the carb, it is a BOCar, 34PICT-3, if that helps at all.

How hard are the jets to replace and what would you recommend as far as jets? I will keep it up there in the summer and at 1300 feet in the summer so I guess I will have to go back and forth with the jets.
Any VW shops in the Big Bear area that you know of?

Thanks all,

Rick
ManxManiac
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Re: Carburators at altitude

Post by ManxManiac »

Before I put the dual Kadrons on Xena's 1600cc, I ran a single Brosal 34 pict 3 carb! I put a 130 main gas jet in it & made sure my 009's timing was set at 30* BTDC @ 3000 rpms!!! It worked real well up at Big Bear & here by the ocean in Ventura & up at Pismo!!! While up at Big Bear, I also kicked the timing up to 32* @ 3000 rpms & it ran even better!!! After installing the dual Kadron 40mm carbs, though I had other sizes of jets, I didn't switch any & it ran fine at Big Bear or at the coast!!! I always made sure the timing was correct at 30* @ 3000 rpms!!! I did try 32* with the dual carbs, but there wasn't enough difference to warrant my changing the timing!!!

On your carb... you access the main jet by unscrewing the plug that on the outside of the fuel bowl, right at the bottom (on right side.. I think), then using a wider blade screwdriver, unscrew the main jet, replace it with you other one!!! You don't have to over tighten it, just make sure it is snug! Then screw the plug back in, crank it over to get some gas in it & it should fire up!!!
You might want to pull your sparkplugs & either clean them real well or install new ones... I highly recommend BOSCH W8AC (gap at .028" w/point ignition or .045" if you are running a "points replacement module" or electronic ignition... with points, dwell - 52*-54*) if the plugs you remove have the short threads, 1/2" reach, not the 3/4" reach!!! If you are running points, you should check them with a dwell meter too!!!
Last edited by ManxManiac on Thu Jun 23, 2016 3:22 pm, edited 1 time in total.
Michael Cates
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Momboy007
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Re: Carburators at altitude

Post by Momboy007 »

Thanks Maniac for all your help!
Do I need to change any other jets, pilot, idle or anything else? I have a pointless distributor that I know works real well.
Would you recommend a carb change?
I am sorry I am very new to the buggy thing.

Thanks again for all your help

Rick
Momboy007
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Re: Carburators at altitude

Post by Momboy007 »

Hello All,

Sorry I forgot to ask, will most auto stores sell these jets?

Thanks,

Rick
Momboy007
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Re: Carburators at altitude

Post by Momboy007 »

Sorry, back again,

Are these Bocar carbs called Weber's also?

Thanks,

Rick
Tom-Kathleen
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Re: Carburators at altitude

Post by Tom-Kathleen »

On the ECVW 2014 trip all the buggies had carbs and we went to the top of Mt. Evans & Pikes Peak (both over 14,000') with no problems. We were told to advance the timming @ 4-5 degrees for a little extra power. We must have gotten lucky with the jet selection. Tom Iacoboni
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RedBaronofRedBud
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Re: Carburators at altitude

Post by RedBaronofRedBud »

I jetted down when we were in Denver on the ECVW14. We all went 5 deg more advance also and it worked well. Made it up and down all the mountains with little problems.

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5150bossman
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Re: Carburators at altitude

Post by 5150bossman »

They are not the same carb. The closest to a Weber would be an Empi HPMX, but both are different than any type of stock Solex.
ManxManiac
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Re: Carburators at altitude

Post by ManxManiac »

Bocar & Brosal 34 pict carbs are clones of German Solex 34 pict carbs that came on VW engines from the factory! The jets do interchange! Do you know if anyone has every changed the main jet in your carb??? You can find jets at most VW parts shops! Depending on where you live, there could be one near you! Also, depending on which carb you have (smog or non-smog), you'll probably have a 127.5 (non-smog)main gas jet or a 123.5 (smog) or smaller! I never changed my air jet, just the main jet! What type of exhaust system are you using???
On my engine I ran a 130 main jet, but that would probably be too rich on your engine! You should also check to make sure your carb's choke is fully opened after it is warmed up!
Michael Cates
ManxManiac
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Ventura, CA
Original Meyers Manx "Xena"
M1609C8S22
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