RP 95# inj..
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TECH Senior Member
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From: GA, USA
RP 95# inj.. Just flow tested a set of #744 RP 95PPh injs, and found something interesting.[Turbo Buick, c-16 race gas]
I checked the ohm values of all 6. They were all at 1.6. When I tested for shorts to the body, 2 were none, and 4 were reading continuity.
I discussed this w/ the inj bench rep. He said the the RP's had fuel flowing around the coil, for heat control, and it may be that the race gas had degraded the coil insulation.[I'm going to cut 1 open and see how it's made.]
He went on to say that some time ago, driveability problems were found, with inj pulse dropping out at certain pulsewidths. He said RP had built a tester to check the volt drop across the coil. A list of acceptable values was published.[I've not seen this]
I got involved w/ the testing as the car owner reported that the first pass was logged at 1% correction on the FAST datalog. The next pass was +24%. A complete teardown of the fuel system revealed no issues..
He sent me a second set of the same part #. They flowed "deadon", and had 1.6 ohm readings and no shorts indicated.
Would the intro of a "shorted coil" affect the operation of the injs, such as altering the offset, accuracy of open time??
We are looking for some "history lesson/education" as to what may be going on..
NE1 have some input[s]???
The "shorted" set is not going back in the car.
I checked the ohm values of all 6. They were all at 1.6. When I tested for shorts to the body, 2 were none, and 4 were reading continuity.
I discussed this w/ the inj bench rep. He said the the RP's had fuel flowing around the coil, for heat control, and it may be that the race gas had degraded the coil insulation.[I'm going to cut 1 open and see how it's made.]
He went on to say that some time ago, driveability problems were found, with inj pulse dropping out at certain pulsewidths. He said RP had built a tester to check the volt drop across the coil. A list of acceptable values was published.[I've not seen this]
I got involved w/ the testing as the car owner reported that the first pass was logged at 1% correction on the FAST datalog. The next pass was +24%. A complete teardown of the fuel system revealed no issues..
He sent me a second set of the same part #. They flowed "deadon", and had 1.6 ohm readings and no shorts indicated.
Would the intro of a "shorted coil" affect the operation of the injs, such as altering the offset, accuracy of open time??
We are looking for some "history lesson/education" as to what may be going on..
NE1 have some input[s]???
The "shorted" set is not going back in the car.
A short to the body could cause problems.... current seeks the path of lest resistance, so it may not open the injector if the body is grounded, or at least some current bypasses the coil & does not work towards opening the injector.
Thread Starter
TECH Senior Member
iTrader: (3)
Joined: Jun 2004
Posts: 5,639
Likes: 71
From: GA, USA
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