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> choking dual carbs?
last337
post Feb 5 2013, 09:24 AM
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I had a lot of trouble the other day getting my engine to start. I eventually had to enrich each barrel to get it to fire up then lean it out a bit to smooth my idle a bit after it warmed up. Is there a way to choke these carbs initially to prevent this? Is there an easier way to start the engine when cold?
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rhodyguy
post Feb 5 2013, 10:11 AM
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what is your warm engine idle speed? unless your webers have the cold start devices (cable operated), there's no provision for "choking" the webers. the butterfies are pretty much in the closed position at idle. by "enrich each barrel" did you turn the idle speed adjustment screws or the idle air/fuel mixture needle screws? which ever, you shouldn't have to do that.

for a cold engine, dual carbs:
1. turn key to first position so you can hear the pump running.
2. give the gas pedal a few stabs. the pump jets will shoot fine streams of fuel down the throats. priming them.
3. while cranking, just give it a touch of pedal so it catches and manually keep the idle @ 1.5ishk (or less. whatever it takes so the engine doesn't die) rpm and hold it there for a minute or so. release pedal. the idle might be a bit low but should rise in a short period of time.

k
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mrbubblehead
post Feb 5 2013, 12:31 PM
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(IMG:style_emoticons/default/agree.gif)

when properly tuned, just a few pumps on the accelerator pedal should bring it to life on the coldest of mornings. and a few minutes of nursing to keep it alive is perfectly acceptable. we are enthusiast drivers, not just steering wheel holders. we understand that using these high performance carburetors we have to give up the choke. so we deal with the popping, farting, hissing, and evil glares from our neighbors. until we reach operating temperature, then you better get the hell outta the way (IMG:style_emoticons/default/driving.gif)
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SUNAB914
post Feb 5 2013, 12:36 PM
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When cold turn ignition so that fuel pump runs and give it three full pumps, then start car. If that doesn't do it, then check proper adjustment or rebuild the cards. it shouldn't be like that.
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last337
post Feb 5 2013, 02:41 PM
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I will try again and see how it goes. It runs great once it warms up!

I am still looking for an improvement for my exhaust but so far the only option I can find is around $1000. I saw a thread about the OBX headers that are on ebay awhile back. Anyone have any better experience with those or anything comparable price-wise?

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brant
post Feb 5 2013, 02:44 PM
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obx headers are a night mare...

go with SSI heat exchangers or a reputable header
sometimes used headers (good ones) come along

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rhodyguy
post Feb 5 2013, 04:43 PM
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a grand for a muffler? you can put together a COMPLETE system that allows you the option of heat when you want it for far less than that. you're going to want heat. let me know if that pm helps with your high idle.

k
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wndsrfr
post Feb 6 2013, 07:08 AM
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QUOTE(last337 @ Feb 5 2013, 12:41 PM) *

I will try again and see how it goes. It runs great once it warms up!

I am still looking for an improvement for my exhaust but so far the only option I can find is around $1000. I saw a thread about the OBX headers that are on ebay awhile back. Anyone have any better experience with those or anything comparable price-wise?


Get Chris Foley's tangerine headers they are an investment, will never lose their value and you'll be able to sell them after you move the car on elsewhere. My 2 cents worth...you probably won't miss heat in NOLA!!!
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rhodyguy
post Feb 6 2013, 08:08 AM
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well he may not need heat in NO but if he should ever drive some place (new mexico, colorado, essentially north of the state line to some elevation) a cold morning will make him a believer in heat. i experienced 2 months worth of cold mornings @ FORT POLK in 1972. if he should ever sell his car the buyer pool gets limited with headers.

the CFR headers are beauties but for their cost a bit of a waste of money for no appreciable hp gains.
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last337
post Feb 6 2013, 08:25 AM
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My current heat exchangers are not all that bad just the outer shell is rusted badly. Has anyone welded boxes onto them to replace the original branch pieces. I was thinking something like what CFR does.
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brant
post Feb 6 2013, 09:14 AM
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QUOTE(last337 @ Feb 6 2013, 07:25 AM) *

My current heat exchangers are not all that bad just the outer shell is rusted badly. Has anyone welded boxes onto them to replace the original branch pieces. I was thinking something like what CFR does.



buy a set of SSI's
if the outer stock shells are rusted you have to start to worry about exhaust leaks
once the inner tube leaks at all, you are pumping that straight into the cabin and breathing toxic fumes...

buy some SSI's
they flow better than stock exchangers and will give you a couple of hp too.
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