Author Topic: Carb rebuild advice!  (Read 10239 times)

Offline Chryco Psycho

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Re: Carb rebuild advice!
« Reply #15 on: April 20, 2015 - 04:24:21 PM »
You can torque the base bolts but I never have just snug them up .
 the choke spring is bi = metallic so it will tighten cold & uncoil as it heats , just leave it alone & line up the drive pin with the loop @ the end of the coil .
 the blue gaskets are not re-usable & stick the same as the older ones but for a few days you should be able to get them apart before they seal up & stick .
 

Challenger - You`ll wish You Hadn`t




Offline Tonker1

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Re: Carb rebuild advice!
« Reply #16 on: April 20, 2015 - 07:59:34 PM »
You can torque the base bolts but I never have just snug them up .
 the choke spring is bi = metallic so it will tighten cold & uncoil as it heats , just leave it alone & line up the drive pin with the loop @ the end of the coil .
 the blue gaskets are not re-usable & stick the same as the older ones but for a few days you should be able to get them apart before they seal up & stick .

Simply lining up to the two components is much easier than trying to work out a way to tighten the spring while mating the black cap to the carb!

Will finish the carb off today and start tuning Friday after work!

Thanks to everyone for all the advice so far! (The 'so far' leaves space for difficulties with tuning!)

Offline Tonker1

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Re: Carb rebuild advice!
« Reply #17 on: April 21, 2015 - 07:24:18 PM »


Offline Chryco Psycho

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Re: Carb rebuild advice!
« Reply #18 on: April 21, 2015 - 08:27:12 PM »
Looking Good  :2thumbs:
 We will see how she runs now

Challenger - You`ll wish You Hadn`t

Offline 734406pk

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Re: Carb rebuild advice!
« Reply #19 on: April 21, 2015 - 08:30:50 PM »
Beautiful job! Looks great!  :thumbsup:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline cudabob496

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Re: Carb rebuild advice!
« Reply #20 on: April 21, 2015 - 08:32:13 PM »
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline Tonker1

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Re: Carb rebuild advice!
« Reply #21 on: April 22, 2015 - 03:32:16 AM »
I really appreciate the comments, thank you!

Before the rebuild, the carb had quite a few leaks which I suspect were effecting the internal fuel/air circuits. The exhaust was always blue and there was bogging when going to wide open throttle regardless of how fuel mixture screws and float heights were set, should note the jets are appropriately sized. With the carb now rebuilt the plan is to do a base tune by checking engine behavior under certain loading. Then once I've had a bit more time with the tig, I'll weld in the bung for an afr gauge that I have, and really get into the finer points of tuning!


Top picture a Nitrous explosion??
Nitrous explosion would be both good and bad, bad for the obvious reasons, but good because I would have a complete NOS set up!

Offline Tonker1

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Re: Carb rebuild advice!
« Reply #22 on: April 25, 2015 - 09:13:05 PM »
It lives! Bonus, there are no petrol leaks!

13 inches of vacuum at 600-800rpm. Overall I would say that is a great success, just have to get the afr bung now!

Thank you for all the help and advice!

Offline 734406pk

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Re: Carb rebuild advice!
« Reply #23 on: April 25, 2015 - 09:15:55 PM »
Excellent job sir! If you have any tuning questions, just post.  :thumbsup:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline cudabob496

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Re: Carb rebuild advice!
« Reply #24 on: April 25, 2015 - 09:21:00 PM »
It lives! Bonus, there are no petrol leaks!

13 inches of vacuum at 600-800rpm. Overall I would say that is a great success, just have to get the afr bung now!

Thank you for all the help and advice!

there's a bolt on bung that you do not have to weld
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline Tonker1

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Re: Carb rebuild advice!
« Reply #25 on: April 25, 2015 - 10:32:31 PM »
Excellent job sir! If you have any tuning questions, just post.  :thumbsup:


Thank you, I appreciate that!

This is the lowest stable idle then engine has ever been at, the miracles of a leak free carb!

Offline cudabob496

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Re: Carb rebuild advice!
« Reply #26 on: April 26, 2015 - 12:47:29 AM »
Thank you, I appreciate that!

This is the lowest stable idle then engine has ever been at, the miracles of a leak free carb!



low idle isn't always that great. It means your water pump and alternator are turning slow, and may
not do the jobs they do as effectively.  My Cuda idles at 1000 rpm.
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline Aracer

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Re: Carb rebuild advice!
« Reply #27 on: April 27, 2015 - 10:55:24 PM »
Don't forget to use pin drills, the correct size to clean all top air bleeds, probably .070 for idle and .035 high speed bleeds, also clean idle feed restrictions and emulsion holes in the metering blocks. While your in there open the emulsion holes up to .033. in order to compensate for today's pump fuels.