1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

turbo 1st gen leaning out need help

Old Dec 28, 2009 | 08:22 PM
  #26  
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What is your boost at when it leans out?
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Old Dec 28, 2009 | 10:57 PM
  #27  
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From: St Joe MO
eBay is probably your best option for finding a surge tank. Personally I prefer the intank pump mod. One less pump to worry about and the plumbing is simpler. You can PM dj55b and Dan S Young to see how they like their modded tanks. One advantage to this option is the tanks are completely refurbished, inside and out, which eliminates the nagging problem of having to deal with an old rusty tank that tends to plug fuel filters.

If this option interests you, PM me for pricing. I have enough parts to do one more tank mod.
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Old Dec 29, 2009 | 12:56 PM
  #28  
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Originally Posted by madazfiend/1
I don't have a msd box I have a stock ignition with a locked dizzy and its alway done this since I've installed it
Does the ignition feel like it's cutting out (bogging)?

Reason why I ask is that the stock ignition would cause a bog for me even with a 2nd gen coil pack on leading. When the ignition cut my wide band would spike lean. Installed a 6A box and that problem went away.

Might not be your issue if your not experiencing any bogging.... Hence the question.

There are many posts out there on the right plugs and gap used to prevent the boost from effecting spark also.

Also the smallest of leaks around the carb and the carb hat have an impact.

There are alot of factors and the only way to effectively work them is one by one. Believe me that hat changes the dynamics alot...
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Old Dec 29, 2009 | 07:14 PM
  #29  
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You need to tune the carb. There is no way robert can sell you a carb that is set up for every situation. Every engine is different and needs a different tune to get it running right. I'm willing to bet your carb just needs to be rejetted. What's in it now?
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Old Dec 29, 2009 | 08:25 PM
  #30  
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From: knox,tn
Originally Posted by Jeezus
What is your boost at when it leans out?
When I'm leaning out its at -10 so its not even boosting
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Old Dec 29, 2009 | 08:32 PM
  #31  
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From: knox,tn
Originally Posted by rx7learner
Does the ignition feel like it's cutting out (bogging)?

Reason why I ask is that the stock ignition would cause a bog for me even with a 2nd gen coil pack on leading. When the ignition cut my wide band would spike lean. Installed a 6A box and that problem went away.

Might not be your issue if your not experiencing any bogging.... Hence the question.

There are many posts out there on the right plugs and gap used to prevent the boost from effecting spark also.

Also the smallest of leaks around the carb and the carb hat have an impact.

There are alot of factors and the only way to effectively work them is one by one. Believe me that hat changes the dynamics alot...
Ya when I drive it it boggs around 3000 rpm and my afr hits lean but when its bogging it makes a nasty noise l
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Old Dec 29, 2009 | 08:35 PM
  #32  
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From: knox,tn
Originally Posted by Hyper4mance2k
You need to tune the carb. There is no way robert can sell you a carb that is set up for every situation. Every engine is different and needs a different tune to get it running right. I'm willing to bet your carb just needs to be rejetted. What's in it now?
Well I think there f11s and119 I beleave
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Old Dec 30, 2009 | 11:44 AM
  #33  
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From: Tampa
Originally Posted by madazfiend/1
Ya when I drive it it boggs around 3000 rpm and my afr hits lean but when its bogging it makes a nasty noise l
I can only speak from a Mikuni perspective, but there is a point where the carb swicthes from your idle jets to you main jets. I ran through every possible size idle jets and main jets till it finally transitioned smoothly because I had the same symptoms. If I drop 1 size in my idle jets the bog comes back.

Now with the weber you have more flexibility in tuning... of which I know little... but if the principle is the same your probably having issues transitioning from idle to main jets.

Heres a link to a weber tuning page... its for an mgb but give you some concepts that you might be able to use. As someone else suggested... no way to jet these carbs for every engine. This is the 2nd 12a the mikuni has been on and I had to re-jet to get it just right.

http://www.teglerizer.com/dcoe/webertune.htm
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Old Jan 6, 2010 | 11:13 AM
  #34  
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From: chatsworth,Ca.
the afr will show a lean mixture at partial throttle. get it to boost and see what the afr's read
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Old Jan 8, 2010 | 08:48 PM
  #35  
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From: knox,tn
Originally Posted by 680RWHP12A
the afr will show a lean mixture at partial throttle. get it to boost and see what the afr's read
Well that's the thing it won't let me boost.I tried to boost and it seemed like the car shut off.afr read 18 then went blank then a big back fire
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Old Jan 9, 2010 | 09:30 AM
  #36  
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You are not listening!! Here's the deal with trouble shooting... START WITH THE EASY STUFF!!! You're already buying new fuel-pumps and talking about building surge tanks. There is no need for either of these things YET. Lot's of people are running Holley Blues with carb/turbo set-ups and no issues. If you thnk that you're starving the pump then fill your gas tank, that will take that variable out of the equation. I posted over 2 weeks ago to check your jets, e-tubes, and float levels. Hyper told you the same thing, and Hyper is definitely our resident weber expert.... it would take you all of 5 mins to unscrew the jet cover and pull the jets out and let us know what they are. If you do have F11 e tubes and there's no such thing as a 119 jet you're more than likely in need of re-jetting. Performance carbs are NEVER a bolt-on and go affair. They will ALWAYS require tunning. f you don't have a FIRM knowledge base of how your carb operates and how to tune the different circuits I HIGHLY recommend you spend the $30 on this book:
http://www.amazon.com/Build-Power-De...3050933&sr=1-4

before you end up spending WAY more on an engine rebuild that you detonated.
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Old Jan 9, 2010 | 07:18 PM
  #37  
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From: knox,tn
Originally Posted by 81WideMariah
You are not listening!! Here's the deal with trouble shooting... START WITH THE EASY STUFF!!! You're already buying new fuel-pumps and talking about building surge tanks. There is no need for either of these things YET. Lot's of people are running Holley Blues with carb/turbo set-ups and no issues. If you thnk that you're starving the pump then fill your gas tank, that will take that variable out of the equation. I posted over 2 weeks ago to check your jets, e-tubes, and float levels. Hyper told you the same thing, and Hyper is definitely our resident weber expert.... it would take you all of 5 mins to unscrew the jet cover and pull the jets out and let us know what they are. If you do have F11 e tubes and there's no such thing as a 119 jet you're more than likely in need of re-jetting. Performance carbs are NEVER a bolt-on and go affair. They will ALWAYS require tunning. f you don't have a FIRM knowledge base of how your carb operates and how to tune the different circuits I HIGHLY recommend you spend the $30 on this book:
http://www.amazon.com/Build-Power-De...3050933&sr=1-4

before you end up spending WAY more on an engine rebuild that you detonated.
Your right I know nothing about my oer sidedraft.I looked at the jets again and there f11 and 190 the car at my moms and ill be over there tomorrow so ill find out the rest... Sorry I've been moving and working and been a dad I haven't had the time here lately ....
thanks ;;Joel
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