Discussion
My AS 383 Torquer (460HP, 505lb/ft) is pinking under heavy load / WOT even > 3000 RPM.
I'm running Optimax.Have an MSD 6AL ignition.
1. Has anyone had a similar problem?
2. Can anyone recommend an advance timing @ specific revs that seems good for them?
3. Any other routes worth taking apart from more retard?
4. Anyone fitted cold air intake as rear under-clip temps seem to get v.high?
Tks,
Adam
I'm running Optimax.Have an MSD 6AL ignition.
1. Has anyone had a similar problem?
2. Can anyone recommend an advance timing @ specific revs that seems good for them?
3. Any other routes worth taking apart from more retard?
4. Anyone fitted cold air intake as rear under-clip temps seem to get v.high?
Tks,
Adam
Adam - This is not unusual. It may be worth a rolling road session to get the car properly set up. With mine, after first hitting the road it was not just one thing but a combination. Mainly timinmg slightly out and running a bit lean.
I had another RR session when the car was about 15 months old and about 5k miles. Worth it just to get the best again.
It may be worth trying a couple of things yourself. You can advance the timming easily enough. Try just advancing it a few degrees and going for a run. Then adjust it again and try again. Your'll know if you've gone too far.
Paul.B
I had another RR session when the car was about 15 months old and about 5k miles. Worth it just to get the best again.
It may be worth trying a couple of things yourself. You can advance the timming easily enough. Try just advancing it a few degrees and going for a run. Then adjust it again and try again. Your'll know if you've gone too far.
Paul.B
Is an MSD dizzy, no vac advance. 2700 miles on the clock.
I believe it came off the crate from AS with 38 degrees. On a visit to the Ultima factory after second hand purchase they road tested and then set it to 36 degress, (2400 miles).
Still pinking though under load - just keep retarding?
Are the octane boosters any help or just a waste of money?
I believe it came off the crate from AS with 38 degrees. On a visit to the Ultima factory after second hand purchase they road tested and then set it to 36 degress, (2400 miles).
Still pinking though under load - just keep retarding?
Are the octane boosters any help or just a waste of money?
Stick a timing light on it and see what youre getting at 3000RPM.
If you have only got a basic one (like me) and you have a 8" damper you can print the one out on my web site and selotape it to your damper:
www.mez.co.uk/ms9.html
Otherwise you need to do the maths to make a new one up.
This is my timing table, taken from a 406ci corvette:
(without vac advance, you are the bottom row)
30 12 19 28 40 45 45 45 45 <-Idle vac
40 10 18 27 39 44 46 46 46
50 8 17 26 38 43 45 45 45
60 6 16 25 37 42 44 44 44
70 5 16 24 36 41 43 44 44
80 5 14 22 34 39 39 39 39
90 5 12 20 32 38 37 37 37
100 5 10 18 30 36 36 36 36 <-WOT
500 900 1500 2400 3300 4200 5100 6000
RPM
edited to add:
Before going completely electronic, I used to have a mallory non vac advance dizzy, i then fitted a std HEI with vac advance - the vac made part/mid throttle much crisper.
>> Edited by eliot on Thursday 16th December 14:37
If you have only got a basic one (like me) and you have a 8" damper you can print the one out on my web site and selotape it to your damper:
www.mez.co.uk/ms9.html
Otherwise you need to do the maths to make a new one up.
This is my timing table, taken from a 406ci corvette:
(without vac advance, you are the bottom row)
30 12 19 28 40 45 45 45 45 <-Idle vac
40 10 18 27 39 44 46 46 46
50 8 17 26 38 43 45 45 45
60 6 16 25 37 42 44 44 44
70 5 16 24 36 41 43 44 44
80 5 14 22 34 39 39 39 39
90 5 12 20 32 38 37 37 37
100 5 10 18 30 36 36 36 36 <-WOT
500 900 1500 2400 3300 4200 5100 6000
RPM
edited to add:
Before going completely electronic, I used to have a mallory non vac advance dizzy, i then fitted a std HEI with vac advance - the vac made part/mid throttle much crisper.
>> Edited by eliot on Thursday 16th December 14:37
Mine is fine with std petrol, 9.25 compression and 36 total advance and with a heavy load (see profile!).
Hence why i said to check where you are right now - it may of moved or something.
I wouldn't of thought you would need to pull more than a couple degrees out of it, if you do - then something else must be wrong. Do a plug-chop on the road and check the colour.
I assume your leads are good and none of the spark plugs are loose, they can make some funny sounds when they start breaking down or come undone. Also check the seperation of the leads - crossfire perhaps?
Indeed, i was thinking of trying a few extra degrees on mine - Thinking along the lines of an "optimax only" ignition map that i can burn in now and then!
Good luck.
Hence why i said to check where you are right now - it may of moved or something.
I wouldn't of thought you would need to pull more than a couple degrees out of it, if you do - then something else must be wrong. Do a plug-chop on the road and check the colour.
I assume your leads are good and none of the spark plugs are loose, they can make some funny sounds when they start breaking down or come undone. Also check the seperation of the leads - crossfire perhaps?
Indeed, i was thinking of trying a few extra degrees on mine - Thinking along the lines of an "optimax only" ignition map that i can burn in now and then!
Good luck.
Gassing Station | Ultima | Top of Page | What's New | My Stuff


