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

sloppy acceleration

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Old May 1, 2002 | 02:04 PM
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sloppy acceleration

my car has a hell of a midrange but not much 5.5-6ish and up. it also seems gear dependent. 1 and 2 have the problem but 3 doesn't seem near as bad.

another problem is that the car's power seems to be flat with the pedal anything but floored. then once floored it takes a second and boom, starts hauling ***. so going up a hill is all or creeping, same for passing. its a little annoying since i like precision in my controls.

i have my regulator at 4.5, going to knock it down to 4 and see if that helps the stock nikki.
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Old May 1, 2002 | 02:11 PM
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From: 3OH5
So basically, the car is bogging when you floor it?
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Old May 1, 2002 | 02:15 PM
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not really bogged, it just does that before it warms up good. its flat. like pushing in the pedal a bit and getting a geo metro increase in hp, then getting pissed because you're still not going anywhere, slamming your foot down and bam, power. sort of all or nothing.
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Old May 1, 2002 | 02:20 PM
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From: 3OH5
Sounds like a carb problem - which I know Jack Schitt about.

Seems like either the accelerator pump needs adjustment, or the pressure which you are working on right now.

But then again, when it comes to carbs, all I know is Jack Schitt
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Old May 1, 2002 | 02:24 PM
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ditto, i was highly surprised when it fired up after i rebuilt the carb. didn't get the choke linkage setup right but, bah, thats what my foot's for.
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Old May 1, 2002 | 02:49 PM
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not really bogged, it just does that before it warms up good.
Ive heards that its EXTREAMLY bad to even try and get on the gas before its completely warmed up due to the differences in the metals used. They expand and contract at different times which makes things not seat/seal well or something, and if you try and get on it like you are talking about, its no good for the engine AT ALL. Someone please correct me if im wrong...Basically just stay off the gas until its fully warm. Youre probably loosing compression and whatnot because its cold or something. If you still have the problem even when its warm, Id say accelerator pump maybe.

~T.J.
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Old May 1, 2002 | 03:00 PM
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if you notice your car idles higher when cold with the choke out. it is meant to do that. mine doesn't since i haven't linked the carb's choke up correctly so i have to sit there and hold the gas in. its not like i'm racing down the street at wot. and even after the choke auto retracts it will bog some and backfire louder until it really warms up.
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Old May 1, 2002 | 03:06 PM
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mine did the same damn thing.......
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Old May 1, 2002 | 03:23 PM
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if you notice your car idles higher when cold with the choke out. it is meant to do that.
Yep, I noticed. 750 idle, 2K choke full on. But my point is that you should be driving slow and steady until she's good and warm. Sorry if I seemed accusing or something, but I was trying to make a point, and the way you described your actions made it sound like you were frustrated cause you couldnt get from one stop light to the next at 40 MPH .
the car's power seems to be flat with the pedal anything but floored. then once floored it takes a second and boom, starts hauling ***
slamming your foot down and bam, power
I dunno, it just sounded like you were trying to drag race her before she was even warm .

~T.J.
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Old May 1, 2002 | 03:47 PM
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no, no. i wait till i see the temp gauge up a touch before i start getting my foot into it.
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Old May 1, 2002 | 04:13 PM
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Re: sloppy acceleration

Originally posted by jeremy
i have my regulator at 4.5, going to knock it down to 4 and see if that helps the stock nikki.
Try somewhere in the 2 - 2.5 range.
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Old May 1, 2002 | 06:13 PM
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Your secondaries sound like they are getting a weak signal for the vacuum. As a result you need to floor it to get them to pop open.
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Old May 1, 2002 | 07:16 PM
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From: Trying to convince some clown not to put a Holley 600 on his 12a.
Originally posted by Directfreak
Sounds like a carb problem - which I know Jack Schitt about.

Seems like either the accelerator pump needs adjustment, or the pressure which you are working on right now.

But then again, when it comes to carbs, all I know is Jack Schitt
"Yer a Fiend!!!"

jeremy-
Your 1 and 2 gears are so fulla torque, that the engine is not under significant load to create the necessary vaccum to pull your secondaries open. When you hit third, you're under a bit of load with a shorter gear ratio, and you're probably fighting some wind, too. So your engine creates a bit more vacuum, pulls open yer seconds.
Now...
You could be suffering from any or a combo of any one of the following:
The seconds are just plain sticking.
The linkage is just plain sticky.
The vacuum diaphragm is torn, or not sealed well, creating a leak.
There is a gasket leak between the throttle body and carb housing where the vacuum signal-to-diaphragm circiut is.
Your accellerator pump is out of tune, and you're getting poor pump shot.

All or any of these things, combined with the simple fact that you did'nt convert your secondaries to mechanical operation, and increase the capacity and stroke of your accelerator pump per my instructions in the write-up entitled, "Carb Crap...Nikki Mods", written by yours truely and found in the 'Archive" section of this forum, spells...
DISASTER!

(I really do think you'll be pleased with the results; especially because you used the key word "Precision". I like that.)

The first-second thing will stay that way (not nearly as bad if correctly tuned) if you stay vacuum secs, but will disappear if you go to mechanical. Go ultra heavy on a replacement spring for the throttle, and you'll be able to feel when the seconds are being opened thru the pedal (and yer ***, too!). It's cool. YOU decide when the secondaries come on!

You will quickly outgrow your stock Nikki, and need it modified.
Check into Paul Yaws site.
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Old May 2, 2002 | 01:55 AM
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From: Troy,Mi
maybe tommorrow i will remove his secondary vacume spring for him to see if that helps any,
since everyone thinks its a secondary fuel problem.
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Old May 2, 2002 | 07:39 AM
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From: Trying to convince some clown not to put a Holley 600 on his 12a.
Do that, But carb cleaner the linkage and throats of the secondaries, too.
I still think that he's screwed around with his accelerator pump, and it is not tuned correctly.

Of course there is the possibily of **** at the bottom of his float bowls.
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Old May 2, 2002 | 11:36 AM
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vacuum problem sounds about right. i'll look into carb mods later. i need a quick fix for the autox this weekend be it i can get the gas tank clean enough to stop dropping rust chunks into the filters.
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Old May 2, 2002 | 11:40 AM
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oh yeah, i cleaned the bowls when i cleaned and rebuilt the carb. the whole thing soaked in carb/gas mix and the had the toothbrush/airgun treatment. i reset the floats per the rebuild instructions.
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Old May 2, 2002 | 11:47 AM
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From: Troy,Mi
Originally posted by jeremy
vacuum problem sounds about right. i'll look into carb mods later. i need a quick fix for the autox this weekend be it i can get the gas tank clean enough to stop dropping rust chunks into the filters.

the spring trick is a quick fix,
four screws,
unscrew,
put them back in,
done

there the ones i showed you on the side of the carb,
it takes all of 5 minutes to do



another thing i just remembered is you atf'd your car with the stock cats !!!!


that just hit me this morning,

man those things are probably toast now.


maybe we should throw up some flex pipe in their place,

i will have plenty left over when i get my exhaust done,

maybe mike p has a mig welder
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Old May 2, 2002 | 01:07 PM
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he forgot mines a 79. no cats, just the thermal detonator avenger reactor thingy.
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Old May 2, 2002 | 01:20 PM
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From: Troy,Mi
well its not that i forgot,
i just didnt know
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Old May 8, 2002 | 10:11 PM
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I have the same problem with acceleration. Someone told me its the 4 barrel card opening only 2 not 4 untill a certain speed. If someone could please tell me how to fix this problem I;d be soo happy......Or maybe I should just get a new carb? Whats A good carb? Holley, Weber or RacingBeat?
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Old May 9, 2002 | 07:55 AM
  #22  
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From: Trying to convince some clown not to put a Holley 600 on his 12a.
Go to the archives and find my write-up. It tells how things work, and why they sometimes don't, and what you can do about them.
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