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

How do you tune a carb?

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Old 07-12-06, 02:40 AM
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Originally Posted by DJAngelicon
My car likes the idle better around 960. Is that good? I mean that is after a full warm up and a good run.
Idle should be 750. If you can't get it there and have it idle smoothly then it's time to find out why. May be a small vacuum leak.
Old 07-12-06, 07:12 AM
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Mine idles @ 650.
Old 07-12-06, 08:21 AM
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I c, well I try using carb cleaner to look for leaks but haven't had any luck with that. I will give it another try again and see if I get lucky. Any idea where I should spray?
Old 11-05-07, 09:44 PM
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mine idles at 3k and have sprayed starting lfuid everyt where and replace every hose and i am stumped. rats nest removed carb stripped. throttle cable maybe??? maybe i should take that off and see if it drops down!
Old 11-06-07, 11:14 AM
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Since you stripped the carb down, you may have buggered the linkage, and/or have multiple leaks.
Old 11-06-07, 11:23 AM
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Did it ever idle correctly? Or did it start after you stripped the carb and rats nest?
Old 11-06-07, 12:01 PM
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Take pictures of your setup. Specifically I'd like to see pictures of the nipples on the carb spacer, a side view of both the passenger and driver's side of the carb and a picture of the air control valve area on the intake manifold.

I should be able to point out some very common vacuum leak spots with that.

But yes, you can remove the throttle cable, set the idle mix screw to 3.5 turns out, and star the car and see what it does. I had a problem for a while where my springs weren't on correctly and it wasn't closing the throttle when I came back down to idle, so try gently closing the throttle by hand without the cable in the way.

How did you strip the carb? were there a set of instructions you followed?

Pics and as much info as you can please.

Jon
Old 11-06-07, 09:54 PM
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got it to idle at 750-800ish but there seems to be a miss. Big throttle return spring was off doh!!! all the mods where done to the car before i got it Urg.... seems my dizzy isnt hooked up right either one line for each pot going to carb. gotta join them and find the static line. i read the thread about that and didnt want to bring it up seemed a touchy issue.

stumble too on first blip of throttle am sure that has to do with ap regulation. Car dosnt have much power below 3 grand either. assumeing thats the dizzy issue though
Old 11-07-07, 04:48 AM
  #34  
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Get the vac advance hooked up (correctly) and it may take care of that stumble when you first get on the accelerator. I used the nipple farthest forward at the base of the carb, took care of it for me. Good luck...
Old 11-07-07, 08:04 AM
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Nice support everyone!
Old 11-07-07, 11:46 AM
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For my car to run smoothly through the RPMs without a stump... I had to richen it... is that ok?
Old 11-07-07, 08:17 PM
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git it handled...and runs like a champ! Thanks evryone
Old 04-18-08, 09:53 PM
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Okay new carb Turbo setup. Regardless of that car idles at like 1,150-1,200 kinda has a lope. THis is a Sa carb with the mixture screw and the big one above. What the heck does the big one do again? IT is kinda idling like a bridge again. I just need clarification on this don't what it to be something gay like side seals or something.
Old 05-05-08, 10:51 AM
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bumpty!
Old 01-29-12, 06:07 PM
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thanks for posting!!!
Old 02-11-18, 01:31 PM
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Originally Posted by yetterben
Okay new carb Turbo setup. Regardless of that car idles at like 1,150-1,200 kinda has a lope. THis is a Sa carb with the mixture screw and the big one above. What the heck does the big one do again? IT is kinda idling like a bridge again. I just need clarification on this don't what it to be something gay like side seals or something.
If you are talking about, the two screws stacked up on the throttle body they are both idle mixture.
https://www.rx7club.com/1st-generati...crease-846768/
here's a thread with the opposite problem but im sure reverse procedure would work. Have you adjusted the actual idle adjustment and not just the mixture screws?
Old 02-11-18, 02:39 PM
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Originally Posted by sloppy79sa
If you are talking about, the two screws stacked up on the throttle body they are both idle mixture.
https://www.rx7club.com/1st-generati...crease-846768/
here's a thread with the opposite problem but im sure reverse procedure would work. Have you adjusted the actual idle adjustment and not just the mixture screws?
You do realize the last post was in 2012?
Old 02-11-18, 02:42 PM
  #43  
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Originally Posted by KansasCityREPU
You do realize the last post was in 2012?
I do but doing my due diligence while doing my homework on here. And for anyone like myself who had the same question. Just providing a concrete answer to the question.
Old 02-11-18, 02:54 PM
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Originally Posted by sloppy79sa
I do but doing my due diligence while doing my homework on here. And for anyone like myself who had the same question. Just providing a concrete answer to the question.
I applaud you on doing the research. I admire someone that educates themselves and shares that information. Good job.
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