dsp/spark arrestor/help

3 replies to this topic
  • YZThump

Posted July 22, 2001 - 03:17 PM


I had heard we would be needing to have a Spark Arrestor installed before the new Hare Scrambles season started this Sept. in Fl. I figured I would go ahead and beat the rush and at the same time save a few #'s and get the Spark Arrestor at the same time. Its a friggin jetting nightmare.Has anyone had any luck with a pipe/spark arrestor that works without changing the stock power and also without the jetting headaches I've been having?

Thanks for your help!

  • troyoda

Posted July 22, 2001 - 03:41 PM


I was looking for a spark arrestor myself and went with the DSP pipe. The jetting recommended by DSP (48 PJ and 170 MJ) is way too rich. I think it’s to minimize their risk in case the engine fails due to an overly lean situation. Start going leaner one step at a time and leave the pilot screw set between 1 1/2 to 2 turns out. The pilot screw is very sensitive. One-quarter turn makes a big difference. I’ve got a stainless DSP w/spark arrestor on my 2001 426 and I found the best settings with a 45 PJ, 168 MJ and 1 1/4 turns out on the pilot screw for up to 1000 feet. Be patient and thank the designers for the access bolt on the bottom of the carb.

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  • YZThump

Posted July 22, 2001 - 04:02 PM


Hey ,thanks for the reply.I went to a 165 and 45 and it blubbered so bad I could barely ride it ,then I went to a 42 Pilot now it is rideable but just doesn't feel right,I'm so pissed I spent this money on this pipe!!!I've seen the posts on the BK mod but is this for real???? Any suggestions for a sparkarrestor only????

[This message has been edited by YZThump (edited 07-22-2001).]

  • troyoda

Posted July 22, 2001 - 04:33 PM


I was in the same boat you were. I put the 48 PJ in and went to the track and couldn't corner worth a damn because it was too rich. I through my stock 42 PJ back in and it felt much better. You might want to stick with the 42 and play with the pilot screw. Experiment by backing it out one-quarter turn until it starts feeling too rich at low throttle or you loose throttle response when you turn it quickly. Then turn in back in one-quarter turn.

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