348 timing

[johnnyrod]

Well we set timing at 35 degrees at 2500 rpm. Then we checked the timing with the vac adv line pluged. We have 8 dgrees. Is 8 degrees OK she runs good and starts good. MSD dist. John:bow

[Ronnie Russell]

John, Is timing all-in at 2,500 rpm? Did you check 3,000 and 3,500rpm? BTW, total timing to be checked with vacuum control plugged.

[johnnyrod]

We did not have the vac pluged. And we did not take it over the 2500 rpm. Would the timing not be all in ragardless if the vac line was pluged or not? John

[Ronnie Russell]

John, Not sure what you are trying to accomplish. If it is a stock 348-250 , and not intended for racing, simply set initial at 10 dg., with vacuum control plugged, then reconnect vacuum control, set idle, and you will be fine, if there are no problems with the engine. If you are looking for maximum performance, and I assume you have timing tape installed, you want 34 to 36deg of total timing. Total timing is measured with vacuum control disconnected. Unless you have weaker dist. springs installed, it may take up to 4,500 rpm for cent advance to be fully activated. So measuring at 2,500 really does not mean anything because the mech advance is not fully open. You must monitor timing light while revving engine until you see highest reading. To change the rate of advance, you will have to use weaker dist. adv. springs to allow the mech advance to open sooner. Thus, total timing can be fully activated at a lower rpm,, 2,500 , instead of 4,500. I am not too good at explaining things, so maybe someone else can make it more clear.

[CDNpontiac409guy]

Ronnie, not to good at explaining things ?
It don't get any better than that:deal

:coffee:

[johnnyrod]

Thanks Ronnie thats pretty clear. Will do and let you know. Its pretty much stock maybe 300 hp. Just want it to be dialed in per say for econamy and perf. All considered. I cant chirp my tires like some of the other guys on here. John