DYNOed....bad plug wire?

[2001 GTS]

Last Saturday I went to the dyno to get a basic reading of what the car was making. On the first run he clipped the RPM reader to plug wire 3...after the run he said he had no spark reading..and the car put down 383hp and couldn't get a torque number because it didn't read the RPMs. He said there was no spark at all going through the wire. So he moved the reader to plug wire 1...dynoed again, this time it did read the RPMs..car put down 394hp/434tq, but these numbers should be a bit higher. So later that day I was going to get a replacement wire for #3...but decided to check the spark...and with the car started...I pulled the end off the sprk plug..and it does in fact spark. So what do you guys think is going on? Mods: Arrow Rebuild, Tubes/Filter, RT X-Pipe, and no cats.

 

[Anaconda]

Why would he use #3???

 

[Russ M]

Never check spark on a coil pack without a plug in the wire, you can and will ruin the coil pack.

How many miles on the motor? Perhaps its time for new plugs, maybe wires.

Is this a dyno jet? Do you have other viper pulls to compare it to on that dyno? Every dyno facility is different no 2 will give you identical results, the best way is to compare against other similar cars to see how yours is doing.

 

[2001 GTS]

12K miles on the motor.

It was a dynojet, a LS1 RX7 with a few bolt ons put down 350hp/355tq..and with 150shot put down 481p/502tq.

 

[GTS Bruce]

Hp/Tq sounds about right.My car with headers,no cats(3" pipe)to 3 " corsa,K&N,smooth tubes made about 430/470 on a dynojet.I think most stock 01-02 make just under 400rwhp completely stock. GTS Bruce

 

[dansauto]

I had same problem. Vipers are hard to get a spark reading. I am sure your car was running ok. If it was not you would definitely have heard a skip. Have him call Sean Roe or Jason Heffner. There is a trick to getting a spark reading from the coil packs on these cars.

 

[Edoggrc51]

Just dynoed mine. 427 HP and 453TQ.

 

[2001 GTS]

Just dynoed mine. 427 HP and 453TQ.

^^I was looking for those kind of numbers. How much is the weather here affecting the hp/tq numbers?...here in South Carolina that day it was around 90-95 degrees...70-80% humidity.