Is NOS bad for an L
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From: Stinkin Joisey
Now, that ENTERTAINMENT
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From: Selden NY
@ ClonetekTHAT IS GREAT CLONETEK, YOU GOT ME GOOD
HAHHAHAHAHAHAHHAHHAHAHAHAHHAAHAHAHHAHHAHAHAHAHHAAH AHAHHAHHAHAHAHAHHAAHAHAHHAHHAHAHAHAHHAAHAHAHHAHHAH AHAHAHHAAHAHAHHAHHAHAHAHAHHAAHAHAHHAHHAHAHAHAHHAAH AHAHHAHHAHAHAHAHHAAHAHAHHAHHAHAHAHAHHAAHAHAHHAHHAH AHAHAHHAAHAHAHHAHHAHAHAHAHHAAHAHAHHAHHAHAHAHAHHAA
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From: Selden NY
Where were we, oh ya timing 
timing varies for different trucks in different climates, and there's a very narrow 'timing window' that a given combo will run well with. A few degrees advanced or retarded from this window, and power drops off big time. When we say degrees, such as 16 or 18 degrees of timing, thats describing degrees in crankshaft movement BTDC (before top dead center). Top dead center is the point where the piston and rod are completely vertical on the crankshaft, and the piston is highest up in the bore and closest to the cylinder head.
When the spark ignites the air/fuel charge, it takes time for it to burn (duh!). The engine is actually accelerating faster than the a/f charge can burn, so the a/f charge needs a head start. The charge doesn't explode in the cylinder (like a nitro burning top fuel dragster), rather its similar to dropping a match in the center of a dry grassy field. It starts to burn slowly at the point closest to the plug (called lag angle), then the flame speed gets faster and faster as it burns in a circular patern away from the spark. Obviously there's going to be a point in the burning cycle with very little energy, and a point where lots of energy is released.
Different climates directly affect the flame speed. If its cold and dry, you need less timing because the flame burns faster. On the other hand, if you live in a warm and humid climate, the air/fuel charge will be less oxygenated and the flame speed will be slower...you'll need more spark advance. If you get the spark ignited too early (too much timing), the engine will detonate because you're releasing energy on the piston while its still moving up the bore on the compression stroke. If you get the spark ignited too late in the cycle (too little timing), you'll lose power because the burning a/f charge will be chasing the piston down the bore on the power stroke.
The trick is to time the spark so the point at which maximum energy is released corresponds to a favorable angle of the pistons/rods/crank (usually 7 or so degrees ATDC), so the engine can convert cylinder pressure to rotaional movement (torque). You want the air/fuel charge to be burning at a high rate when the piston is near TDC, because this is the point of maximum compression, quench, and heat. Despite what you may have read on the internet, once the intake valve closes you want maximum heat in the cylinder for maximum cylinder pressure. Again, you're trying to create maximum cylinder pressure. Cylinder pressure=horsepower, less pressure=less power, more pressure=more power. When you install a ported blower or pulley or chip or air filter, you're making more power because of more cylinder pressure.
The sign of a very well designed, highly efficient engine combo is it needs very little timing to make good power. That efficiency comes from a well designed combo of cam, heads, intake manifold and header tuning. If you want good examples, check out Honda. They have cars operating with 40:1 a/f ratio's, that only drop to around 20:1 when throttled and never detonate! Adding timing is actually negative work, because as the piston moves up the bore on the compression stroke it has to fight against a large, rapidly expanding cloud of gas when you've got lots of timing. This slows the piston down, which reduces power. Again, its a delicate balancing act. You can also do severe engine damage by running extremely low timing (6-9*). The exhaust valve is the absolute hottest point in your engine, and with low timing the a/f charge will still be burning as the exhaust valve opens. This overheats the valve very fast, and the first thing to get damaged will be the valve seat which is a very critical seal for making power. Also, you may have seen cars on dynoes before with headers glowing bright red. Thats caused from very low timing, because the a/f charge is actually still burning inside the header.
Thanks rscoleman
timing varies for different trucks in different climates, and there's a very narrow 'timing window' that a given combo will run well with. A few degrees advanced or retarded from this window, and power drops off big time. When we say degrees, such as 16 or 18 degrees of timing, thats describing degrees in crankshaft movement BTDC (before top dead center). Top dead center is the point where the piston and rod are completely vertical on the crankshaft, and the piston is highest up in the bore and closest to the cylinder head.
When the spark ignites the air/fuel charge, it takes time for it to burn (duh!). The engine is actually accelerating faster than the a/f charge can burn, so the a/f charge needs a head start. The charge doesn't explode in the cylinder (like a nitro burning top fuel dragster), rather its similar to dropping a match in the center of a dry grassy field. It starts to burn slowly at the point closest to the plug (called lag angle), then the flame speed gets faster and faster as it burns in a circular patern away from the spark. Obviously there's going to be a point in the burning cycle with very little energy, and a point where lots of energy is released.
Different climates directly affect the flame speed. If its cold and dry, you need less timing because the flame burns faster. On the other hand, if you live in a warm and humid climate, the air/fuel charge will be less oxygenated and the flame speed will be slower...you'll need more spark advance. If you get the spark ignited too early (too much timing), the engine will detonate because you're releasing energy on the piston while its still moving up the bore on the compression stroke. If you get the spark ignited too late in the cycle (too little timing), you'll lose power because the burning a/f charge will be chasing the piston down the bore on the power stroke.
The trick is to time the spark so the point at which maximum energy is released corresponds to a favorable angle of the pistons/rods/crank (usually 7 or so degrees ATDC), so the engine can convert cylinder pressure to rotaional movement (torque). You want the air/fuel charge to be burning at a high rate when the piston is near TDC, because this is the point of maximum compression, quench, and heat. Despite what you may have read on the internet, once the intake valve closes you want maximum heat in the cylinder for maximum cylinder pressure. Again, you're trying to create maximum cylinder pressure. Cylinder pressure=horsepower, less pressure=less power, more pressure=more power. When you install a ported blower or pulley or chip or air filter, you're making more power because of more cylinder pressure.
The sign of a very well designed, highly efficient engine combo is it needs very little timing to make good power. That efficiency comes from a well designed combo of cam, heads, intake manifold and header tuning. If you want good examples, check out Honda. They have cars operating with 40:1 a/f ratio's, that only drop to around 20:1 when throttled and never detonate! Adding timing is actually negative work, because as the piston moves up the bore on the compression stroke it has to fight against a large, rapidly expanding cloud of gas when you've got lots of timing. This slows the piston down, which reduces power. Again, its a delicate balancing act. You can also do severe engine damage by running extremely low timing (6-9*). The exhaust valve is the absolute hottest point in your engine, and with low timing the a/f charge will still be burning as the exhaust valve opens. This overheats the valve very fast, and the first thing to get damaged will be the valve seat which is a very critical seal for making power. Also, you may have seen cars on dynoes before with headers glowing bright red. Thats caused from very low timing, because the a/f charge is actually still burning inside the header.
Thanks rscoleman
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From: Stinkin Joisey
Originally posted by VINNIE
LMAO,, I noticed the same thing when I read it.
I am sure though he will be back with a 10 page disortation on how Timing effects global warming or something
VINNIE
LMAO,, I noticed the same thing when I read it.
I am sure though he will be back with a 10 page disortation on how Timing effects global warming or something
VINNIE
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From: burleson,tx
is nitrous bad
i have used it to some extent on 2 lightings. 1 a 2000 did very well and with a chip and gas it only took out 2 drive shafts. that was on stock block and 175 shot. no.2 did not do as well it took out 2 rods. on a 250 shot. i have as of late started to purge into cab before each run and it does not help the et but i donot mind as bad. if i purge several times i do think i am going faster,as for timing i think more is better but it could be worse i have to go now i think my timing is of or i may be out of gas?
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From: NEW JERSEY
Re: is nitrous bad
Originally posted by benyouall
i have used it to some extent on 2 lightings. 1 a 2000 did very well and with a chip and gas it only took out 2 drive shafts. that was on stock block and 175 shot. no.2 did not do as well it took out 2 rods. on a 250 shot. i have as of late started to purge into cab before each run and it does not help the et but i donot mind as bad. if i purge several times i do think i am going faster,as for timing i think more is better but it could be worse i have to go now i think my timing is of or i may be out of gas?
i have used it to some extent on 2 lightings. 1 a 2000 did very well and with a chip and gas it only took out 2 drive shafts. that was on stock block and 175 shot. no.2 did not do as well it took out 2 rods. on a 250 shot. i have as of late started to purge into cab before each run and it does not help the et but i donot mind as bad. if i purge several times i do think i am going faster,as for timing i think more is better but it could be worse i have to go now i think my timing is of or i may be out of gas?
HMM.......Broken Driveshaft with a 175 shot and broken rods w a 250 shot. What are the odds
Again if Nitrous is used properly you will be fine. A 250 shot on a stock block is just a recipe for distruction.
VINNIE
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From: Abilene, TX
Sorry to bring this post back but listen, my L has a 6lb crank pulley and other basic mods like a cold air and Borla cat back. Is it SAFE to spray it with a 125 shot or should I decrease it. I do have a superchips module set up for the spray.
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From: alabama
Originally posted by ND4SPD
Sorry to bring this post back but listen, my L has a 6lb crank pulley and other basic mods like a cold air and Borla cat back. Is it SAFE to spray it with a 125 shot or should I decrease it. I do have a superchips module set up for the spray.
Sorry to bring this post back but listen, my L has a 6lb crank pulley and other basic mods like a cold air and Borla cat back. Is it SAFE to spray it with a 125 shot or should I decrease it. I do have a superchips module set up for the spray.
no way....bump it down!
