Benjemin Bale

Hello everyone again . I belive I am having a timing issue I would like to see if we can work out. I have an old Electromotive HPV 1 twin plug ignition with crank trigger . Since it has been cooler about 50 degrees around here in KY a couple of days I have noticed a slight ping in the motor under full boost . I know the fuel is there IA fuel head Leask adjustable regulator with rpm switch 50/50 mix of 93 octane and 110 race fuel k 27 turbo 1 bar spring sc cams etc.. My big question is how to retard the ignition to solve this - the ping is very slight but safer then sorry is the way to go. I can see the adjustment dials by the coils but have no idea how to adjust - was on the car when I bought it . Do I need to use a timing light and if so how do I mark the crank pully - it has notches on it for the trigger - paint one of the notches white and hit with a light like an old v8. Any help will be great..... Thanks again Ben

JBrown

I have the Electromotive XDI system. If it is similiar, you should have 3 dials. The first one is for intial timing. The second one is for how much advance you want. The 3rd dial is for retard . If you are getting pinging up top in the revs, I would assume you either want to retard the timing alittle more by adjusting the 3rd dial or you could turn down the 2nd dial to take away total timing. I think I exsplained it right.

WERK-I

Here's a link to the HPV-1 documentation. Go to page 14 and it will discuss the timing techniques.
There's no MAP compensation, so I generally calculate where full boost comes on and retard the timing appropriately. With twin plug engines, you'll want around 24-26 degrees(total) BTDC @ 6K RPM at your boost levels.
http://www.directignition.com/pdf_files/hpv1.pdf

Benjemin Bale

Thanks for the help , I belive I have four dials to play with. I will go to that web site and see what I can come up with . Will keep you informed.

JBrown

Yes 4 dials, I am sorry. the last one is for rpm limiter.

WERK-I

Actually, there's 8 (2x4).