North American Turbocoupe Organization



Timing advance
TurboT Offline
Member
#1
What does the timing advance accually do by itself in our cars? I see people setting it to 12 and 13 degree's. Now is that advance or retard, and what direction is that in terms of on the car from the from the bumper lookin into the engine compartment. And finally what should mine be set at? Help
T.J.
FORCED INDUCTION RULES!!!
86 Turbo Cougar
Boost Valve, New Boost Gauge
FMIC, Finally new rear Rubber
Newer Stock Turbo @ 16psi
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57fan Offline
Member
#2
First the engine should timing shuld be set at 10 degrees at idle with the spout connector removed. This will set the basic mechanical timing and once the spout connector is reinstalled the ECU will then adjust the timing accordingly to many factors the computer see's going on in the engine. The timing should be set 10 degrees BTC (before top dead center) (advanced). Looking at the timing marks on the front engine cover, the timing mark is the number 10 towards the top of the engine.
87 Turbo, 5 spd, full loaded with sun roof.
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TurboT Offline
Member
#3
Ok, that makes sense, but why do some guys here, go beyond that 10 deg. mark...what benefit does that give? I mean in older V8s and such it created hp, but that was before computer controlled everything. Does it help us, or do I need a new computer first?
T.J.
FORCED INDUCTION RULES!!!
86 Turbo Cougar
Boost Valve, New Boost Gauge
FMIC, Finally new rear Rubber
Newer Stock Turbo @ 16psi
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DonH Offline
Posting Freak
#4
Got your PM. I've tried it but in my case it didn't seem to make any difference. When you set the base timing the computer advances timing from that point based on a table in the computer. If you set the base timing higher the total advance will be higher so the effect is the same as in an older car. The computer is equivalent to the weights and springs in the advance mechanism of a mechanical distributor in this case combined with a vacuum advance. In theory you would set the timing to the point where the engine starts pinging and then retard it to the point where the pinging stops for best fuel economy and most power but I don't think that one or two degrees has much effect in our cars and is within the margin of error of setting the timing anyway.
1987 TC stock except ATR 2.5"
1983 Pontiac Transam T-top 5.7 T56 [email protected] top speed: 176mph
1978 Fairmont 2.3 4-spd Big-top S/W
1946 Willys CJ2A 134.2ci L4 No-top
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TurboT Offline
Member
#5
Ok, so basically it isn't a mod to play to indepth with, and hope to get a noticable difference in performance. Well, thank you for the advice, now I just gotta work out the rest of my bugs and I will be in good shape...thanks again
T.J.
FORCED INDUCTION RULES!!!
86 Turbo Cougar
Boost Valve, New Boost Gauge
FMIC, Finally new rear Rubber
Newer Stock Turbo @ 16psi
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Jeff K Offline
Administrator
#6
My personal experience is the advancing the base timing several degrees improves off boost and low boost power / response. Every motor / every combo is different, some may respond well to advancing timing, some may not. I have my base timing set at 16 deg, and when I go in for emissions testing, I reset it back to 10 deg to keep NOx down, and the car feels like a real pig.
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Pete D Offline
Administrator
#7
What Jeff said. I run 12-13* advance because the cam I have is also advanced and any more ignition advance than 14 is counter productive http://natomessageboard.com/uploads/0000...small2.JPG
Pete Dunham


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Robert Camp Offline
Posting Freak
#8
Pete,
I would like to clarify your meaning about cam advance. Sorry if this is basic to everyone else but I want to be clear in my understanding of cam advance/retard. When you advance a cam I assume it's to open the valves earlier. Using the marks on the cam sprocket and inner valve cover assembly, this would mean moving the cam sprocket mark clockwise from the normal cam timing mark on the inner cover assembly?
Robert Camp
'86 Medium Regatta Blue TC, 5-speed, original owner.
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grey88smokin Offline
Posting Freak
#9
To adjust the cam timing you need an adjustable cam pully. You can not just jump it a tooth because thats like 12*+ IIRC.
84 SVO 1C
08 MKZ
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Pete D Offline
Administrator
#10
Robert,
You got the concept. As was mentioned, you do need an adjustable cam sprocket. Advncing a cam brings the power peak down in the rpm range and retarding the cam tends to give more power at the top end. Which way to go and how much depends on the cam and the desired results.
Pete Dunham


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