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Discussion Starter · #1 ·
tfi upgrade done-a couple more ?\'s

Finished the upgrade last night and it seems much peppier, no pinging and starts much easier. I still haven't changed the plugs yet and I was wondering since I changed over from the prestolite ('75) to the duraspark if I should use the later plugs. The Chiltons plug number for '75 is N-12Y and for '77 and newer it's RN-12Y. I don't know what the difference is but my comon sense is leaning toward the later kind, and should I open the gap to .040 since I have the tfi coil? Also what's the best timing setting. It varies by year and ranges from 2 1/2 BTDC to 10 BTDC. I'm currently set a 5 BTDC.

Chris
 
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Discussion Starter · #2 ·
Re: tfi upgrade done-a couple more ?\'s

i was at a buddies the other day who just happens to have a dyno in his shop!!! and we dyno'd my jeep with
bosh double platnuim's,and then ac del.rapid fire both at 40...the rapid fires came out ahead with 5 more hp...
kewl huh!!!

fullsize jeep fanatic
oh yeah> the bigger the better
 
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Discussion Starter · #3 ·
Re: tfi upgrade done-a couple more ?\'s

I run my gap in my 258 w/ TFI at .045, but a lot of guys run them up to .060. I found that it would run better when cold if I closed the gap up from .050 to .045. I dont have the answer to your other two questions. My guess would be that the timing setting is related to emmisions requirements for certain years, just advance the timing until it starts to miss, then back it off until it stops. Brendan

Proud owner of the world's best running Carter BBD
 
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