XDI Ignition advance advice

[rstanley87]

I rebuilt my 3.2 with stock cams and have added weber 40 IDA carbs, a cat bypass and magnaflow muffler. Im running an electromotive XDI ignition. Ive read that the advance should be 5 btdc at 900 rpm and 30 btdc at 6000rpm . The XDI has an 1000rpm advance setting .Then it has settings for the 3000 and 8000 rpm. Any advice on where to start on the settings? Thanks Ron

[MBruns]

single or twinplug ?

[rstanley87]

Single.

[MBruns]

I would give it a little more initial timing more like 10 -12 deg at idle, on a single plug you should be able to run around 34 deg. total depending on comp. ratio and fuel quality, so in theory you should set the init. dial to 12 and the 3000 dial to 22 and the 8000 dial to zero, the rev dial is vague on those and need to be tested to confirm. once you set the dials and depending on who's pulley and sensor mount you have be sure to confirm the event with a good timing light. as far as the 8000 dial we have found on most systems you have what is called timing drift, usually retards timing as it gets near max but its something that needs to be checked and usually needs to be done on a dyno, as it happens slowly (you wont see it free reving) say it drifts 4 deg on top and you want a solid 34 total at that point you would dial in +4 on the 8000 dial and recheck it. Or if you had a boosted engine and wanted to pull timing out on the upper end it would be a - number. Most of the XDi systems we have tested over the years they have been pretty good, the older HPV1 ans HPX units would drift a ton I have seen 10 + degrees retard up top with the dials set at zero.

Mike Bruns JBRacing.com

[rstanley87]

Thanks