I don't do timing with the strobolight...
Discussion
The timing data that TVR gave out is probably the best to use, it takes advantage of the advance curves they put in the dizzy's.
You could find max advance anywhere that would be wrong somewhere else, or even cause problems when you got a little hotter or even your fueling leaned out a bit. Publicly advocating using most advance before pre-ignition could lead to tears IMHO. Ending up with too much advance at low rpm could also result in a pretty horrible drive.. There are a lot of factors that are different when you have a mappable ignition that you can't take advantage of with a std dizzy.
You could find max advance anywhere that would be wrong somewhere else, or even cause problems when you got a little hotter or even your fueling leaned out a bit. Publicly advocating using most advance before pre-ignition could lead to tears IMHO. Ending up with too much advance at low rpm could also result in a pretty horrible drive.. There are a lot of factors that are different when you have a mappable ignition that you can't take advantage of with a std dizzy.
spend said:
The timing data that TVR gave out is probably the best to use, it takes advantage of the advance curves they put in the dizzy's.
You could find max advance anywhere that would be wrong somewhere else, or even cause problems when you got a little hotter or even your fueling leaned out a bit. Publicly advocating using most advance before pre-ignition could lead to tears IMHO. Ending up with too much advance at low rpm could also result in a pretty horrible drive.. There are a lot of factors that are different when you have a mappable ignition that you can't take advantage of with a std dizzy.
I know a mappable ignition would be the best option but I have to ''work'' with what I have...giving max advance I find out that the car expresses the best performance when it's not very hot, still it pulls strong at higher then 3.000rpms even if it's very hot, below that mark the car gets pretty undrivable in traffic and does not hold the idle. When only warm it goes strong at any rev level and it does not ping under full load with any temp.You could find max advance anywhere that would be wrong somewhere else, or even cause problems when you got a little hotter or even your fueling leaned out a bit. Publicly advocating using most advance before pre-ignition could lead to tears IMHO. Ending up with too much advance at low rpm could also result in a pretty horrible drive.. There are a lot of factors that are different when you have a mappable ignition that you can't take advantage of with a std dizzy.
I guess setting the engine with just a tad more retard it would get more ddriveable under conditions but I fear to loose precious hp...
I got it right?
Opinions?
If you really are interested there are lots articles on the net, try something like:
http://www.innovatemotorsports.com/resources/myths...
which should give you some basic ideas.
http://www.innovatemotorsports.com/resources/myths...
which should give you some basic ideas.
To be bluntly honest no you cant set the timing the way you are doing it, well you can set it as a best guess but it will never be optimized, running an engine on the edge of "knock" detonation is not allways going to produce maximum power, after years of working solely on these engines the best advance for power has always been around 28 deg, although most engines will take more than this and in certain cases a range rover engine 400 tiv engine will take upto and beyond 50 deg of advance the power will start dropping off quite rapidly, you are trying to aim for the cylinder "explosion" to happen just as the piston is about to go down on its power stroke, by running to much ignition what you could end up with is the total burn happening before the piston has even reached tdc, this will leed to knock, a simple comparison imagine climbing a ladder and you are nearly at the top and suddenly somebody goes and drops a bag of cement on your head! "start of the burn" your going to be dazed and it will slow you down, now if you have got to the top and somebody drops a ton of cement on your head you are going to plummit straight to the ground very fast!
v8 racing said:
To be bluntly honest no you cant set the timing the way you are doing it, well you can set it as a best guess but it will never be optimized, running an engine on the edge of "knock" detonation is not allways going to produce maximum power, after years of working solely on these engines the best advance for power has always been around 28 deg, although most engines will take more than this and in certain cases a range rover engine 400 tiv engine will take upto and beyond 50 deg of advance the power will start dropping off quite rapidly, you are trying to aim for the cylinder "explosion" to happen just as the piston is about to go down on its power stroke, by running to much ignition what you could end up with is the total burn happening before the piston has even reached tdc, this will leed to knock, a simple comparison imagine climbing a ladder and you are nearly at the top and suddenly somebody goes and drops a bag of cement on your head! "start of the burn" your going to be dazed and it will slow you down, now if you have got to the top and somebody drops a ton of cement on your head you are going to plummit straight to the ground very fast!
What I do is just test the engine (driving the car in different conditions, mainly open road/motorway) at every change of the advance...and choose the dizzy position once I feel it's going properly, I won't feel the power difference of course but I would indeed feel how it runs, I've got this car since the '96 when I bought new and I know when the engine is too retarded or two advance...with the right timing the engine sounds and runs smoothly and it does not ping at full throttle at any given rev level, also the idle is more regular both when cold and hot.I started doing this way after that for years I've been trying to do it with the strobo, it was never right, for some reason the marks on my engine front are not right, I've tried the figures everybody says are the best but never obteining a decent result anyway.
spend said:
If you really are interested there are lots articles on the net, try something like:
http://www.innovatemotorsports.com/resources/myths...
which should give you some basic ideas.
What I've leart in this article, if I well understood, is that a real U-turn for properly timing the engine would be a mappable ecu...infact if at changed conditions (temp,load, etc) the timing should be optimized consequently then it means that the dizzi should be good only for dumping as it marks the same timing in any conditions.http://www.innovatemotorsports.com/resources/myths...
which should give you some basic ideas.
Did I miss something?
Dizzys have weights in them to advance as you spin faster, hence the manufacturers (TVR) defined the advance curve. If you replace the dizzy with a LR or other one it may be quite different, hence the earlier comment about noting the way TVR say to set their timing.
Yes a mappable ignition gives you much more control ~ and carefully mapped the ability to achieve maximum power under varied conditions, as well as much finer control at lower speeds BTW.
Dizzies are only forced on racers by regulations not by choice if thats what you are thinking
Yes a mappable ignition gives you much more control ~ and carefully mapped the ability to achieve maximum power under varied conditions, as well as much finer control at lower speeds BTW.
Dizzies are only forced on racers by regulations not by choice if thats what you are thinking
panic said:
v8 racing said:
To be bluntly honest no you cant set the timing the way you are doing it, well you can set it as a best guess but it will never be optimized, running an engine on the edge of "knock" detonation is not allways going to produce maximum power, after years of working solely on these engines the best advance for power has always been around 28 deg, although most engines will take more than this and in certain cases a range rover engine 400 tiv engine will take upto and beyond 50 deg of advance the power will start dropping off quite rapidly, you are trying to aim for the cylinder "explosion" to happen just as the piston is about to go down on its power stroke, by running to much ignition what you could end up with is the total burn happening before the piston has even reached tdc, this will leed to knock, a simple comparison imagine climbing a ladder and you are nearly at the top and suddenly somebody goes and drops a bag of cement on your head! "start of the burn" your going to be dazed and it will slow you down, now if you have got to the top and somebody drops a ton of cement on your head you are going to plummit straight to the ground very fast!
What I do is just test the engine (driving the car in different conditions, mainly open road/motorway) at every change of the advance...and choose the dizzy position once I feel it's going properly, I won't feel the power difference of course but I would indeed feel how it runs, I've got this car since the '96 when I bought new and I know when the engine is too retarded or two advance...with the right timing the engine sounds and runs smoothly and it does not ping at full throttle at any given rev level, also the idle is more regular both when cold and hot.I started doing this way after that for years I've been trying to do it with the strobo, it was never right, for some reason the marks on my engine front are not right, I've tried the figures everybody says are the best but never obteining a decent result anyway.
wycoller said:
panic said:
v8 racing said:
To be bluntly honest no you cant set the timing the way you are doing it, well you can set it as a best guess but it will never be optimized, running an engine on the edge of "knock" detonation is not allways going to produce maximum power, after years of working solely on these engines the best advance for power has always been around 28 deg, although most engines will take more than this and in certain cases a range rover engine 400 tiv engine will take upto and beyond 50 deg of advance the power will start dropping off quite rapidly, you are trying to aim for the cylinder "explosion" to happen just as the piston is about to go down on its power stroke, by running to much ignition what you could end up with is the total burn happening before the piston has even reached tdc, this will leed to knock, a simple comparison imagine climbing a ladder and you are nearly at the top and suddenly somebody goes and drops a bag of cement on your head! "start of the burn" your going to be dazed and it will slow you down, now if you have got to the top and somebody drops a ton of cement on your head you are going to plummit straight to the ground very fast!
What I do is just test the engine (driving the car in different conditions, mainly open road/motorway) at every change of the advance...and choose the dizzy position once I feel it's going properly, I won't feel the power difference of course but I would indeed feel how it runs, I've got this car since the '96 when I bought new and I know when the engine is too retarded or two advance...with the right timing the engine sounds and runs smoothly and it does not ping at full throttle at any given rev level, also the idle is more regular both when cold and hot.I started doing this way after that for years I've been trying to do it with the strobo, it was never right, for some reason the marks on my engine front are not right, I've tried the figures everybody says are the best but never obteining a decent result anyway.
panic said:
Yes, I have to review the timing every one or two months (or longer, depending on the use), for some reason (unknown to me), once arrived to the best tweek, the engine keeps it for sometime but I have to go back and redo it after sometime...I've asked why on this forum and to a garage buddy, the guy told me that's impossible.
Ambient temperature and Barometric pressure will have an effect on how the engine feels under load. Sounds like you are adjusting the advance for this suttle change, as the timing can't change unless the dizzie isn't clamped down after adjustment properly.Gassing Station | Griffith | Top of Page | What's New | My Stuff