Benefits Of Advancing Timing?
02-07-02, 02:22 PM
#1
WTB S5 N/A FC
Thread Starter
Join Date: Oct 2001
Location: College Station, Tx
Posts: 2,778
Likes: 0
Received 0 Likes
on
0 Posts
Benefits Of Advancing Timing?
What are the benefits of advancing your timing? I keep seeing people do this, and I am curious. Also, what is the procedure for doing this? I have a 91 n/a, pretty well stock except Weapon R intake, wired open VDI and ports, no air pump, and soon to have Bonez Racepipe and Racing A SS exhaust, if that helps.
02-07-02, 02:36 PM
#4
Rotary Freak
My timing is advanced through the roof and i use 87. Seems to make my car feel a little better and I noticed a small power difference right away. My vary thou from car to car.
02-07-02, 02:40 PM
#6
i am not a girl
iTrader: (13)
Join Date: Aug 2001
Location: CT
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
advance timing, by looking in the manual on how to do it, u really can only do this perfectly on a dyno, but u can drive it and see teh diffrence, also make sure u dotn advance it too much so it doesnt start knocking on u
02-07-02, 02:47 PM
#7
WTB S5 N/A FC
Thread Starter
Join Date: Oct 2001
Location: College Station, Tx
Posts: 2,778
Likes: 0
Received 0 Likes
on
0 Posts
SO the Hayne's manual tells ya how to do this? Wel, I guess I had better get to reading! Thanks all!
How far is safe to advance the timing?
How far is safe to advance the timing?
Trending Topics
02-07-02, 03:05 PM
#8
mad scientist
Originally posted by von
My timing is advanced through the roof and i use 87. Seems to make my car feel a little better and I noticed a small power difference right away. My vary thou from car to car.
My timing is advanced through the roof and i use 87. Seems to make my car feel a little better and I noticed a small power difference right away. My vary thou from car to car.
02-07-02, 03:08 PM
#10
I'm a boost creep...
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes
on
8 Posts
Don’t flame me for this but I’m going to explain it in terms of a piston engine because it’s easier to visualise, but the theory is exactly the same for a rotary.
You want the ignited fuel/air mix to reach peak explosive pressure just after the piston has passed top dead centre (TDC) and started to travel downwards. This will impart the maximum downwards force on the piston for the longest time. If that peak pressure is reached a bit later, you’ve wasted some of the piston’s stroke, resulting in less power. If it reaches peak pressure to early, i.e. before the piston has reached TDC and is still travelling upwards, the pressure actually slows the piston down and wastes some of the charge’s energy (because it’s not pushing the engine in the right direction), plus this places massive stresses on the engine resulting in wear and damage.
The reason the spark is fired before TDC is because it takes time for the spark to ignite the mixture and for the mixture to burn. Obviously it’s only a few fractions of a second but as the cycle duration gets shorter as revs climb (60ms @ 1000rpm, 8.57ms @ 7000rpm) you need to fire the spark earlier at higher rpm.
So there is a “sweet spot” for your timing that produces max power. Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine. The stock timing setting will be slightly retarded in the interests of safety.
Sorry for the long-winded post but I hope that answers the original question.
You want the ignited fuel/air mix to reach peak explosive pressure just after the piston has passed top dead centre (TDC) and started to travel downwards. This will impart the maximum downwards force on the piston for the longest time. If that peak pressure is reached a bit later, you’ve wasted some of the piston’s stroke, resulting in less power. If it reaches peak pressure to early, i.e. before the piston has reached TDC and is still travelling upwards, the pressure actually slows the piston down and wastes some of the charge’s energy (because it’s not pushing the engine in the right direction), plus this places massive stresses on the engine resulting in wear and damage.
The reason the spark is fired before TDC is because it takes time for the spark to ignite the mixture and for the mixture to burn. Obviously it’s only a few fractions of a second but as the cycle duration gets shorter as revs climb (60ms @ 1000rpm, 8.57ms @ 7000rpm) you need to fire the spark earlier at higher rpm.
So there is a “sweet spot” for your timing that produces max power. Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine. The stock timing setting will be slightly retarded in the interests of safety.
Sorry for the long-winded post but I hope that answers the original question.
02-07-02, 03:15 PM
#11
WTB S5 N/A FC
Thread Starter
Join Date: Oct 2001
Location: College Station, Tx
Posts: 2,778
Likes: 0
Received 0 Likes
on
0 Posts
WOW, that is awesome info! So how far should I advance it?
Man, that is one of the most informative answers to one of my questions I have ever received! (Mental note:Add NZConvertable to Rico's List Of Heros...)
Man, that is one of the most informative answers to one of my questions I have ever received! (Mental note:Add NZConvertable to Rico's List Of Heros...)
02-07-02, 03:27 PM
#12
mad scientist
If anybody is having their top end fall off after advancing your timing, use higher octane. Thats preignition causing power to drop off. It wont kill your n/a engine, but isnt good for it either.
02-07-02, 03:44 PM
#14
i am not a girl
iTrader: (13)
Join Date: Aug 2001
Location: CT
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
hey how much is it u are trying ot advance your timign again?
"advance it and you’ll lose power and do mucho damage to your engine"
this is not true u will gain power not throughout the powerband though
"advance it and you’ll lose power and do mucho damage to your engine"
this is not true u will gain power not throughout the powerband though
Originally posted by NZConvertible
Don’t flame me for this but I’m going to explain it in terms of a piston engine because it’s easier to visualise, but the theory is exactly the same for a rotary.
You want the ignited fuel/air mix to reach peak explosive pressure just after the piston has passed top dead centre (TDC) and started to travel downwards. This will impart the maximum downwards force on the piston for the longest time. If that peak pressure is reached a bit later, you’ve wasted some of the piston’s stroke, resulting in less power. If it reaches peak pressure to early, i.e. before the piston has reached TDC and is still travelling upwards, the pressure actually slows the piston down and wastes some of the charge’s energy (because it’s not pushing the engine in the right direction), plus this places massive stresses on the engine resulting in wear and damage.
The reason the spark is fired before TDC is because it takes time for the spark to ignite the mixture and for the mixture to burn. Obviously it’s only a few fractions of a second but as the cycle duration gets shorter as revs climb (60ms @ 1000rpm, 8.57ms @ 7000rpm) you need to fire the spark earlier at higher rpm.
So there is a “sweet spot” for your timing that produces max power. Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine. The stock timing setting will be slightly retarded in the interests of safety.
Sorry for the long-winded post but I hope that answers the original question.
Don’t flame me for this but I’m going to explain it in terms of a piston engine because it’s easier to visualise, but the theory is exactly the same for a rotary.
You want the ignited fuel/air mix to reach peak explosive pressure just after the piston has passed top dead centre (TDC) and started to travel downwards. This will impart the maximum downwards force on the piston for the longest time. If that peak pressure is reached a bit later, you’ve wasted some of the piston’s stroke, resulting in less power. If it reaches peak pressure to early, i.e. before the piston has reached TDC and is still travelling upwards, the pressure actually slows the piston down and wastes some of the charge’s energy (because it’s not pushing the engine in the right direction), plus this places massive stresses on the engine resulting in wear and damage.
The reason the spark is fired before TDC is because it takes time for the spark to ignite the mixture and for the mixture to burn. Obviously it’s only a few fractions of a second but as the cycle duration gets shorter as revs climb (60ms @ 1000rpm, 8.57ms @ 7000rpm) you need to fire the spark earlier at higher rpm.
So there is a “sweet spot” for your timing that produces max power. Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine. The stock timing setting will be slightly retarded in the interests of safety.
Sorry for the long-winded post but I hope that answers the original question.
02-07-02, 03:53 PM
#16
Rotary Enthusiast
If your engine is ported the whole timming stuff changes. Remember... Porting is the equivalent of performance cams. It all depends on who's hand the grinding tool is on 
02-07-02, 03:55 PM
#17
I'm a boost creep...
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes
on
8 Posts
Kahren, reread the post. I was referring to advancing it further than the point that produces max power, not from the stock setting. The reason you advance it from stock is to try and find that point.
Sorry Rico I have no experience with advanced ignition timing on rotaries, I've always just left it stock (I've only had turbos).
Sorry Rico I have no experience with advanced ignition timing on rotaries, I've always just left it stock (I've only had turbos).
02-07-02, 04:10 PM
#19
i am not a girl
iTrader: (13)
Join Date: Aug 2001
Location: CT
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
sorry didnt understand u right
but now i see this, "Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine." u mean the other way around right
but now i see this, "Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine." u mean the other way around right
Originally posted by NZConvertible
Kahren, reread the post. I was referring to advancing it further than the point that produces max power, not from the stock setting. The reason you advance it from stock is to try and find that point.
Sorry Rico I have no experience with advanced ignition timing on rotaries, I've always just left it stock (I've only had turbos).
Kahren, reread the post. I was referring to advancing it further than the point that produces max power, not from the stock setting. The reason you advance it from stock is to try and find that point.
Sorry Rico I have no experience with advanced ignition timing on rotaries, I've always just left it stock (I've only had turbos).
02-07-02, 04:23 PM
#20
I'm a boost creep...
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes
on
8 Posts
Originally posted by Kahren
sorry didnt understand u right
but now i see this, "Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine." u mean the other way around right
sorry didnt understand u right
but now i see this, "Retard it form there and you will lose efficiency and power, advance it and you’ll lose power and do mucho damage to your engine." u mean the other way around right
02-07-02, 05:14 PM
#21
I came, I saw, I boosted.
Join Date: Apr 2001
Location: Windsor, Ontario, Canada
Posts: 1,921
Likes: 0
Received 0 Likes
on
0 Posts
Quoted from Angel Guard Racing Team
Man- I'd hate to be the guy with the tool... I wouldn't want any grinding tool ON my hand!!
Just kidding man... anyways...
In terms of porting- it still doesn't change how far you can advance the timing- because combustion can still happen before the optimal point- not to the point to too much combustion is happening while the chamber is still in compression
Porting is the equivalent of valve timing on a piston engine. Ignition timing is STILL ignition timing on a rotary or piston.
Maybe I am missing something, but I don't see how porting could modify the desired ignition timing unless you are WAAYYY retarded (the timing of course!!!!), because the exhaust port is uncovered a bit sooner- interupting full combustion...
I don't know why anyone would have timing that retarded that extreme amount though.
If I am wrong here... someone please correct me!
My 2 cents- I have the timing advanced about 10 degrees (1 cm on the wheel) before the stock pin... I noticed an immediate improvement in smoothness and power.. Runs better- But I have a ported engine... which by what I said shouldn't change anything anyways..?
It all depends on who's hand the grinding tool is on
Just kidding man... anyways...
In terms of porting- it still doesn't change how far you can advance the timing- because combustion can still happen before the optimal point- not to the point to too much combustion is happening while the chamber is still in compression
Porting is the equivalent of valve timing on a piston engine. Ignition timing is STILL ignition timing on a rotary or piston.
Maybe I am missing something, but I don't see how porting could modify the desired ignition timing unless you are WAAYYY retarded (the timing of course!!!!
), because the exhaust port is uncovered a bit sooner- interupting full combustion...I don't know why anyone would have timing that retarded that extreme amount though.
If I am wrong here... someone please correct me!
My 2 cents- I have the timing advanced about 10 degrees (1 cm on the wheel) before the stock pin... I noticed an immediate improvement in smoothness and power.. Runs better- But I have a ported engine... which by what I said shouldn't change anything anyways..?
02-07-02, 08:11 PM
#22
Full Member
Join Date: Jan 2002
Location: Richmond Virginia
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
How exactly do you advance the timing ? Like where in the engine is it since there are no pistons?? I mean is there a special tool.. because i have a really bad acceleration problem... any ideas ? I think the timing needs to be advanced.. i am running 97 octane and it solves the problem of the top end fall off but, i wanna know how and where to adjust it at... and degrees as in ? like turn clockwise or counter clock ? HELP !!..... AAAHhhhhhhhhhhhhhhhhhhhhhhhh
02-07-02, 08:20 PM
#23
I'm a boost creep...
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes
on
8 Posts
Originally posted by SoulPyr0
Like where in the engine is it since there are no pistons??
Like where in the engine is it since there are no pistons??
02-07-02, 08:58 PM
#25
Full Member
Join Date: Oct 2001
Posts: 231
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by SoulPyr0
How exactly do you advance the timing ? Like where in the engine is it since there are no pistons?? I mean is there a special tool.. because i have a really bad acceleration problem... any ideas ? I think the timing needs to be advanced..HELP !!..... AAAHhhhhhhhhhhhhhhhhhhhhhhhh
How exactly do you advance the timing ? Like where in the engine is it since there are no pistons?? I mean is there a special tool.. because i have a really bad acceleration problem... any ideas ? I think the timing needs to be advanced..HELP !!..... AAAHhhhhhhhhhhhhhhhhhhhhhhhh