Re: DA getting better, ET and MPH are not!
[Re: JCCuda]
#1322700
10/19/12 05:13 PM
10/19/12 05:13 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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120 needle and seats will be plenty... since you jetted up and no change I would do 2 things... try the N/S and do a flow test on the pump... you will have to use a can hanging above to run the engine and measure the time to flow a gal from the pump right where it goes into the carb 
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Re: DA getting better, ET and MPH are not!
[Re: JCCuda]
#1322702
10/19/12 08:06 PM
10/19/12 08:06 PM
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Joined: Feb 2005
Posts: 4,316
Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,316
Prospect, PA
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Quote:
I am going to try and put a fuel pressure gauge on the car to see whats going on with that.
If you have 5 psi at WOT at the top of any gear, you are fine. It is hard to believe that those carbs don't have enought needle orifice to support 400 hp, but it wont hurt to put larger ones in.
Did you put the return line in before or after you went 107+ in the summer? You could simply plug or by pass that at the track to see if it makes a difference.
It is a street car right? What all has happened with the car since the summer track passes? How many miles have you put on it? You're looking for about 10 to 15 "missing" hp. Really not that much. The state of tune and the car/engine details could simply be a little different. Things like fresh plugs, tire pressure, shift point, oil, oil temp and engine cool down can add up to make this kind of a difference in my street cars between having the car really ready, verses showing up to make some passes.
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Re: DA getting better, ET and MPH are not!
[Re: BSB67]
#1322703
10/20/12 10:40 AM
10/20/12 10:40 AM
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Joined: Apr 2009
Posts: 447
NJ
JCCuda
OP
mopar
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OP
mopar
Joined: Apr 2009
Posts: 447
NJ
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Quote:
Did you put the return line in before or after you went 107+ in the summer? You could simply plug or by pass that at the track to see if it makes a difference.
It is a street car right? What all has happened with the car since the summer track passes? How many miles have you put on it? You're looking for about 10 to 15 "missing" hp. Really not that much. The state of tune and the car/engine details could simply be a little different. Things like fresh plugs, tire pressure, shift point, oil, oil temp and engine cool down can add up to make this kind of a difference in my street cars between having the car really ready, verses showing up to make some passes.
I put the return line in after I started racing the car this year and it didn't seem to make any difference in the ET or MPH. It did keep the car from stalling and not starting right away when driving it in the hot weather. I might plug the return just to double check though.
Yes it is a street car but I have raced it almost every Wed. night in a $500.00 eliminator since, so tire press. oil, oil temp., plugs are not a factor and I go into my burnout at 145-150 every pass. I replaced my clutch fan with a water pump drive in the middle of August. (saw no change in mph or et from that either?)so I'm not just showing up to make some passes. These are some good thoughts. You made me go back and double check my memory on these items. Thank You.
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Re: UPDATE DA getting better, ET and MPH are not!
[Re: JCCuda]
#1322704
07/12/13 11:38 AM
07/12/13 11:38 AM
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Joined: Apr 2009
Posts: 447
NJ
JCCuda
OP
mopar
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OP
mopar
Joined: Apr 2009
Posts: 447
NJ
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Finally got back to the track Wednesday night. I put in the .120 needle and seats and added a Holley electric fuel pressure gauge, changed the rear float bowl for one with a notched float and jet extensions also raised the rear float level. At idle the fuel press. is 5 psi. Driving through the pits it's 7 psi and on the track it's 3-4 psi so I suspect this is probably the issue. A friend used to work for IROC and he has one of the mechanical Holley pumps they used to run on the Daytona's and Avengers so he's going to give that to me to try. DA was about 2,900' and the temp. was 88 and humid. Best pass was 12.517 @ 106.87 which is right inline with last years numbers. Still no color on the plugs. I will also try plugging the return line for racing.
Last edited by JCCuda; 07/12/13 12:53 PM.
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Re: UPDATE DA getting better, ET and MPH are not!
[Re: JCCuda]
#1322707
07/12/13 05:56 PM
07/12/13 05:56 PM
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Joined: Jan 2003
Posts: 32,394
Quicktree
I Win
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I Win
Joined: Jan 2003
Posts: 32,394
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Quote:
Finally got back to the track Wednesday night. I put in the .120 needle and seats and added a Holley electric fuel pressure gauge, changed the rear float bowl for one with a notched float and jet extensions also raised the rear float level. At idle the fuel press. is 5 psi. Driving through the pits it's 7 psi and on the track it's 3-4 psi so I suspect this is probably the issue. A friend used to work for IROC and he has one of the mechanical Holley pumps they used to run on the Daytona's and Avengers so he's going to give that to me to try. DA was about 2,900' and the temp. was 88 and humid. Best pass was 12.517 @ 106.87 which is right inline with last years numbers. Still no color on the plugs. I will also try plugging the return line for racing.
color on the plug tells you nothing..
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Re: UPDATE DA getting better, ET and MPH are not!
[Re: Quicktree]
#1322708
07/12/13 10:43 PM
07/12/13 10:43 PM
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Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
cudadoug
master
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master
Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
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Quote:
Quote:
Finally got back to the track Wednesday night. I put in the .120 needle and seats and added a Holley electric fuel pressure gauge, changed the rear float bowl for one with a notched float and jet extensions also raised the rear float level. At idle the fuel press. is 5 psi. Driving through the pits it's 7 psi and on the track it's 3-4 psi so I suspect this is probably the issue. A friend used to work for IROC and he has one of the mechanical Holley pumps they used to run on the Daytona's and Avengers so he's going to give that to me to try. DA was about 2,900' and the temp. was 88 and humid. Best pass was 12.517 @ 106.87 which is right inline with last years numbers. Still no color on the plugs. I will also try plugging the return line for racing.
color on the plug tells you nothing..
Exactly. In the old days we'd tune by plug color by making a run on FRESH plugs, shutting off at the finish line and coasting to the return road. We'd look at plus right then. Putting back to the trailer would color the plugs and not tell us anything.
Since then, with these high powered ignitions, color on the plus is almost meaningless. if it's THAT lean, it won't run. If it's THAT rich you wouldn't be able do drive it.
The best way to see your mixture is with EGT readings. Period. BUT...remember that a mechanical pump is subject to ALOT more heat soak than an electric pump...THUS you having issues during hot weather driving.
An electric pump, even a "street/strip" Carter or like should show you a gain. Just remember to wire it THROUGH the ignition switch so it shuts off with the key.
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The current pump(ethahno 10 or 15%) swill needs more volume than the gas of old 
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