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carb tuning? video added

Posted By: Stroker Scamp

carb tuning? video added - 07/12/11 05:21 AM

so if the air gets better and your car doesnt improve does that mean its lean? explain your thoughts, thanks btw i run 84 jets square in a holley 950 no pv, car ets from 10.30 to a best of 10.14 no changes in tuning just weather
Posted By: Cab_Burge

Re: carb tuning? - 07/12/11 07:37 AM

Quote:

so if the air gets better and your car doesnt improve does that mean its lean? explain your thoughts, thanks btw i run 84 jets square in a holley 950 no pv, car ets from 10.30 to a best of 10.14 no changes in tuning just weather


I would think that your motor is not running fat if it doesn't pick up when the air get better How much better weather are we talking about as far as actaul air temps, humidity and baro. pressure changes? My car slowed down .006( 6.688 ET 1/8 mile) when the air temps went from 71.4F with 40.2% humidity with Baro. Pres. of 27.39(actual) at 11.10 A.M. to 80.4 F with 28.7 % humidity and 27.34 B.P. at 1.39 PM in Madras this weekend with a 6.694 ET the MPH didn't change from 102.74 to 102.74 MPH The AFR on it are right at 12.8 to 13.3 AFR for the entire run now My intrepretations have alwyas been that if the car picks up when the air gets better the carb. jetting is fat IHTHs. BTW, I'm going to Woodburn in two weeks for the Mopar race so we will see what it does there now that it seems to have enough fuel supply for the entire run instead of running out from the starting line on like it was the last race there according to the wide ban
Posted By: Stroker Scamp

Re: carb tuning? - 07/13/11 03:33 AM

Cab, see ya there, I pretty sure im too lean I have a in car video and you can hear what sounds like a lean missfire, I will see if I can post it. I did not have the DA readings at this race but it was in the mid 70's fyiw
Posted By: Stroker Scamp

Re: carb tuning? - 07/14/11 06:00 AM

heres a vid from in car what do you heer? http://www.youtube.com/user/kimkrzy#p/a/u/0/Zh2Y_B6uGHE btw i forgot to tun the camera off so you get a ride back to the pits
Posted By: Stroker Scamp

Re: carb tuning? - 07/15/11 02:40 AM

give the video a listen and tell me what u think
Posted By: toddd

Re: carb tuning? - 07/15/11 02:46 AM

How fresh are the plugs?

Mine did the same thing, but a plug change cleaned it up.

Is it me or does the miss go away near the end of the run???.

What is the jetting now?
Posted By: Brian Hafliger

Re: carb tuning? - 07/15/11 03:04 AM

seems like high rpm miss...hard to tell though.
Ever check valve springs for pressure?
Ever make a run and pull a plug? Any pics?
What's the jetting at now?
Spacer?
Do you run mufflers?
What plug?
Everything look good in the dist.?
Ever check ohms on plug wires?
What valve lash do you run?
Posted By: Stroker Scamp

Re: carb tuning? - 07/15/11 04:13 AM

Plugs may have 20 runs on them
never pulled a plug after the run
jetting is 84 sq no pv
1"spacer
bullet mufflers
ngk 8's
went thru the dist, wires and springs when i was chasing the backfire
I forgot to add that i added an air pan and no air cleaner, didnt see any slopping of gas from turbulence, i think ill try to add a bit of jet and see what it does next weekend
Posted By: toddd

Re: carb tuning? - 07/15/11 04:21 AM

If you have a high rpm limiter...What is it set at?. I was having problems of it cutting in well before the # I had chosen.

What kind of ign box?
Posted By: Stroker Scamp

Re: carb tuning? - 07/15/11 04:26 AM

Quote:

If you have a high rpm limiter...What is it set at?. I was having problems of it cutting in well before the # I had chosen.

What kind of ign box?


thats a thought msd 6al with a 7200 chip
Posted By: MR_P_BODY

Re: carb tuning? - 07/15/11 04:32 AM

Quote:

Quote:

If you have a high rpm limiter...What is it set at?. I was having problems of it cutting in well before the # I had chosen.

What kind of ign box?


thats a thought msd 6al with a 7200 chip




Pull the high rev chip and try it without a chip...
I've had multiple chips act up.... I have also had
a 7-al give me a high rev miss.... just a light miss
but it was there.... I changed boxes and it was gone
Posted By: Stroker Scamp

Re: carb tuning? - 07/15/11 04:44 AM

Quote:

Quote:

Quote:

If you have a high rpm limiter...What is it set at?. I was having problems of it cutting in well before the # I had chosen.

What kind of ign box?


thats a thought msd 6al with a 7200 chip




Pull the high rev chip and try it without a chip...
I've had multiple chips act up.... I have also had
a 7-al give me a high rev miss.... just a light miss
but it was there.... I changed boxes and it was gone



did your miss sound like the one thats in my vid?
Posted By: MR_P_BODY

Re: carb tuning? - 07/15/11 04:48 AM

Quote:

Quote:

Quote:

Quote:

If you have a high rpm limiter...What is it set at?. I was having problems of it cutting in well before the # I had chosen.

What kind of ign box?


thats a thought msd 6al with a 7200 chip




Pull the high rev chip and try it without a chip...
I've had multiple chips act up.... I have also had
a 7-al give me a high rev miss.... just a light miss
but it was there.... I changed boxes and it was gone



did your miss sound like the one thats in my vid?




I didnt listen to it... I dont try to analyze a miss
over a computer speaker
Posted By: Brian Hafliger

Re: carb tuning? - 07/15/11 04:50 AM

That's very true Mike, and that could be why it's at high rpm only. Pull that chip out!
Posted By: Stroker Scamp

Re: carb tuning? - 07/15/11 04:57 AM

thanks guys ill let ya know how things go when i hit woodburn on 23rd/24th
Posted By: Cab_Burge

Re: carb tuning? - 07/15/11 05:22 AM

Quote:

give the video a listen and tell me what u think


Sounds like it starts missing in the bottom of high gear Check all the plugs and spark plug wires, it might be a fuel delivery issue also. Do the simple stuff first and eliminate the hard stuff last I had a similar miss at the top of high gear that ended up being three spark plug wires, 4,6 and 8
Posted By: sshemi

Re: carb tuning? - 07/15/11 07:24 PM

Im trying to remeber what caused my car to do the exact same thing.
It was not my rev limiter turned it off and rpms were 8300
And it was not lean but maybe fat.
Sh&% i cant remeber.
Posted By: 65_gt_rag_402

Re: carb tuning? - 08/01/11 02:42 AM

you have a lean condition gong on
when you put the air pan on ... it has turbulance and running lean. need to jet up or put the filter back on and try it.
Had same condition on my dart.


Attached picture 6756126-raqggiedriveway5-11BESTBEST.jpg
Posted By: Stroker Scamp

Re: carb tuning? - 08/02/11 06:47 AM

Quote:

you have a lean condition gong on
when you put the air pan on ... it has turbulance and running lean. need to jet up or put the filter back on and try it.
Had same condition on my dart.



put the air cleaner back on and seemed to help a bit but its still breaking up a bit, so the search goes on
Posted By: StrokerPost

Re: carb tuning? - 08/02/11 07:25 AM

Quote:

Quote:

you have a lean condition gong on
when you put the air pan on ... it has turbulance and running lean. need to jet up or put the filter back on and try it.
Had same condition on my dart.



put the air cleaner back on and seemed to help a bit but its still breaking up a bit, so the search goes on



Mike, is this "breaking up" all the time , only at WOT, or top end only? I ran into this a few years back on my Dart, tried jetting, diff plugs, redid all my ignition grounds, checked dizzy shaft for too much play, everything I could think of with no luck, even swapped in my back up 6AL. Then after reading an article about dizzy phasing I decided to check it out. Turns out it was firing JUST before the rotor moved past the electrode for any given cyl. So I corrected that and the breaking up or miss was gone. Mine was a topend miss just about the 1000' mark to the stripe. Just a thought.
Posted By: sshemi

Re: carb tuning? - 08/02/11 09:14 AM

why dont you just pull a/all plug?
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