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12-05-2020, 07:12 PM | #1 |
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LOST 10mph AND ABOUT 6 TENTHS
So, I have gremlins in my car... the motor is fine on the dyno, the MSD and coil from the car are fine on the dyno... the trans is fine - the converter has been sent out and is fine... has anyone had any issues with a Racepak causing an issue like this?? It’s really the only change we made over the winter... car made a few good passes and then lost the time and speed... it’s quite a discouraging problem - if anyone has any ideas, please help!! Thanks!
Joey Cole - GT/DA - 454 BBC - Turbo 350 |
12-05-2020, 07:37 PM | #2 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Check fuel system, , the 30 second jug test is a good start, replace the battery/batteries....Have you done any welding close to the car ? .....Some racers have reported that their car became MAGNETIZED and they lost plenty of ET and MPH ......3 ideas to PONDER ......
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12-05-2020, 07:38 PM | #3 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
In my experience I lost .3 and 3 mph and chased it to find out fuel pump. I had gauge mounted on windshield and always showed the 6 psi range. But it did not have volume. No symptoms of miss or stutter just a full range of loss of ET.
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12-05-2020, 08:09 PM | #4 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Check compression and leakdown , for engine health .
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12-05-2020, 08:15 PM | #5 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Did the fuel system test - all good - the welding is an interesting thought... batteries are pretty new - Racepak shows all good with fuel pressure... but something to think about with the volume - thanks everyone! Keep the ideas coming!!
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12-05-2020, 08:28 PM | #6 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Just curious, how much did it pump in 30 seconds,.....carry on....
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12-05-2020, 08:29 PM | #7 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Gallon in 18 seconds so volume is good
Last edited by monte8616; 12-05-2020 at 08:32 PM. |
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12-05-2020, 08:35 PM | #8 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Not to bash, but it was a Barry Grant pump. It was aerating the fuel. So the gauge was actually air/ liquid pressure. No O2 sensor at the time. Also at the time I was not to smart and threw about 1500.00 and 7al, wires, new tach, plugs. Checked valve springs twice. Cam timing, compression test. Three different outings at track. It was a real learning experience.
Last edited by Jeff Stout; 12-05-2020 at 08:42 PM. Reason: More |
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12-05-2020, 08:36 PM | #9 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
Put the 3 speed back in it...LOL
Do you run foam in the fuel cell? Pull the cap off the fuel cell vent, check the vent for obstructions.
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Adger Smith (Former SS) Last edited by Adger Smith; 12-05-2020 at 08:38 PM. Reason: finish |
12-05-2020, 08:41 PM | #10 |
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Re: LOST 10mph AND ABOUT 6 TENTHS
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