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  Topic Review (Newest First)
03-13-2019 03:31 PM
alfasrule Youz guys make it difficult! All I do is line up the Number One 1 plug wire to the bolt on the valve cover. Been workin' for over 30 years.
Unless some screwed up a timing belt replacement?
03-11-2019 07:20 PM
Alfistaa Yes, well if you want to use regular gas, by all means stay with 2BTDC.
03-11-2019 07:14 PM
Del Our 89 Milano Gold, bought new, pinged going up hills with half throttle or more, using regular grade gasoline. Don't know the timing, not touched ever, but have to use mid-grade fuel where we live, sea level conditions. Doesn't do it at Rocky Mountain altitudes with regular grade, of course.
03-11-2019 05:40 PM
Alfistaa Factory setting of 2BTDC is for smog, produces hotter exhaust to keep your cat working. For driving, with stock pistons you can safely move to 7BTDC. This is the factory spec for 3.0 Milano. You can add more degrees for better performance, but careful you don't want to cause preignition damage. Higher compression pistons will not allow as much advanced timing as stock pistons.
03-11-2019 01:30 PM
superloaf Thanks for the additional timing info and thanks for the 2 degree correction. I readjusted my timing to the correct 2 BTDC and the car passed smog easily. I think i'll probably bump it up a bit as it seemed a little peppier with the advanced timing before i adjusted it. At least i think it did....Not really sure but I'll give it a try and see what happens....
02-22-2019 11:44 PM
Alfistaa Here's an interesting discussion with some useful info about ignition timing and ported vs. manifold vacuum.

https://bangshift.com/forum/forum/ba...vacuum-advance

My 3.0 with standard compression and S like cams is now set at 11BTDC at 900rpm, vacuum off. Also, moved distributor to manifold vacuum resulting in much smoother idle and responsiveness.
02-22-2019 06:11 PM
Gubi Also, if it was that far advanced I'd disconnect the distributor vacuum line and see if the timing changes (it shouldn't on an '87 Milano.) If it does it's possible someone adjusted the idle with the throttle plate rather than the idle bypass, such that you're getting ported vacuum to the distributor at idle (which, again, you shouldn't.) If that's the case you've seriously retarded your static timing, which would explain the sluggishness.

Just trying to think of reasons it would be that far advanced at idle.
02-22-2019 06:08 PM
Gubi
Quote:
Originally Posted by superloaf View Post
How about the stock 2.5 V6? Does it benefit from slight advance of the timing from stock?

I just checked and adjusted my timing in preparation of a smog test and I found the timing to be too advanced so I dialed it back to 7 degrees and now the car seems a little less happy to rev. I think I'll be advancing again once it passes smog but do you have any suggestions for optimal timing for this engine?
Stock advance on the 2.5 Milano is 2 degrees, not 7. Look for the mark on the pulley. If you set it to 7 you won't pass the smog timing check (assuming they do it.)

My old Milano 2.5 was definitely a bit more peppy at 7 static. I didn't go higher than that as I didn't want to risk pinging.
02-22-2019 05:47 PM
alfaparticle My 3L motor has S pistons and it made best power with 34 degrees max advance.
02-22-2019 05:33 PM
superloaf
Quote:
Originally Posted by JoeCab View Post
I find that you will get noticeably better throttle response by bumping the timing a few degrees. At high altitude we use 12 degrees, but at sea level I would gradually work up from the stock 7 degrees and make sure you don't get any pinging.
How about the stock 2.5 V6? Does it benefit from slight advance of the timing from stock?

I just checked and adjusted my timing in preparation of a smog test and I found the timing to be too advanced so I dialed it back to 7 degrees and now the car seems a little less happy to rev. I think I'll be advancing again once it passes smog but do you have any suggestions for optimal timing for this engine?

Thanks and thanks, Joe, for the recent quick shipping of my parts....
04-30-2018 07:13 PM
JoeCab
Quote:
Originally Posted by fourmotioneer View Post
On stock L-jet, are people generally satisfied with setting to 7 degrees static? Any success in deviating from that?
I find that you will get noticeably better throttle response by bumping the timing a few degrees. At high altitude we use 12 degrees, but at sea level I would gradually work up from the stock 7 degrees and make sure you don't get any pinging.
04-30-2018 06:27 PM
alfaparticle I think that if you disconnect the vacuum hose from the distributor you can measure the max advance by using an adjustable strobe on the P mark with the engine at 5000 rpm. If for example it is 30 degrees when your static is 7 degrees then you would move the static to 11 to get 34 degrees max advance.
Also, the manual says disconnect the vacuum hose to check the static timing.
04-30-2018 12:18 PM
fourmotioneer
Quote:
Originally Posted by alfaparticle View Post
That shows how long I have been in Megasquirt mode

The advance curve is not controlled by the distributor but by the advance computer so you cannot change it. You can shift the whole curve by rotating the distributor. I don't remember what the max advance is but I can tell you that on a dyno my 3L motor with "S" pistons made max power at 34 degrees. A lower compression motor might need a shade more. You should not run into starting problems if you keep the static below about 12 degrees.
Good to know with the 34 degrees - thanks for divulging . I'm running 10.1 i.e. "S" pistons.

I guess adjusting springs 'inside the distributor' was referring to adjusting the springs in vacuum advance bit so that the signal to the ignition computer is altered.

Based on the ignition advance curve, looks like static advance would be 34-(12+/-2) = 10+/-4 degrees. Add in 12 degree static constraint and that's 10+2/-4 degrees. I'll do some acceleration runs and see what seems to stick


04-30-2018 11:53 AM
alfaparticle
Quote:
I think that bit in the manual about the vacuum line is a holdover from the older V6 cars that had the vacuum hose connected to manifold vacuum. On the Milano they switched to port vacuum, so there is no vacuum on that line with the throttle at idle (you should see vacuum on the line as soon as you open the throttle plate.)
That shows how long I have been in Megasquirt mode

The advance curve is not controlled by the distributor but by the advance computer so you cannot change it. You can shift the whole curve by rotating the distributor. I don't remember what the max advance is but I can tell you that on a dyno my 3L motor with "S" pistons made max power at 34 degrees. A lower compression motor might need a shade more. You should not run into starting problems if you keep the static below about 12 degrees.
04-30-2018 11:15 AM
fourmotioneer Thanks for the input, Tom and Ed!

On stock L-jet, are people generally satisfied with setting to 7 degrees static? Any success in deviating from that?

Looks like the BB member adjusted springs in distributor to increase static advance without going too far on max/vacuum advance: http://www.alfabb.com/bb/forums/alfe...ml#post4822058
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