Engine Shim Tuning
11-20-2003, 12:49 PM
#31
I just talked to the guy who runs the local model shop and he says a good guide is to have 0.001" head clearance for every 1% nitro above 16% so 16% is 0.016" where 25% is 0.025"
Is this a good guide?
Cheers
Is this a good guide?
Cheers
11-20-2003, 01:01 PM
#32
Originally posted by Corse-R
Let's see if we can shed more light on your comments.
Transfer height (linear measurement) determines timing on a 360 degree wheel. 164 degrees of total timing for the exhaust port determines a height on the exhaust port. If is ROAR legal or not is an issue that should not bother anything. When your engine is teched, the exhaust transfer height is measured on milimeters, not timing degrees and if is higher than 4.5mm, you're deemed illegal and you're out of race.
Reducing on 7mm the conrod lenght is a no no. Shortening the conrod makes to collide the piston skirt with the counterweight of the crankshaft and you need to remove more material from the piston (still, doubt if current pistons can accept to radical material remove) this piston will be weakened up to a point that will be unstable into the sleeve and will rock into the sleeve, scratching it and making it ovalized.
Marine mentality is fine for boats that only rely on high rpms to produce power not for cars that run on a closed track (probably are fine for tether cars or planes too), hence here their exagerated exhaust timings along to ultra-high compression ratios (or ultra small combustion chamber heights - name it as you prefeer) that rely on the extreme timing to control what occurs into the combustion chamber. As a plus, those engines run with a water cooling system, so their temperature never reaches the extreme temperatures you can find in a .12 engine with a closed body.
Edward, probably this is your worst problem, you're directly extrapolating what works on boats to cars, and this doesn't work on all cases. Some of your ideas are interesting, others don't apply, others simply... well.
Here, many people works and make 1:1 engines for a living (Engineers, motor builders, mechanics), others simply are gearheads (like me, have their own experience building their own engines, but their money is earned in other places), other simply rely on the experience of other people because they don't want headaches with engines.
Some of your advices aren't questionable are directly dangerous and harmful to people with light or no knowledge of our engines (0.008" of chamber height is a fine example, another is to make propaganda that for making power, the best is to reduce Nitro on their fuel).
If you're right, all the guys that run on Funny cars or other Top fuel categories are doing a complete nonsense burning a mixture of 90% nitro and 10% of Methanol, running 100% Methanol is much cheaper to run their multi hundred thousands cars burning thousands of dollars on each weekend they run.
On this last assumption, you're extrapolating what happens on FAI categories that are limited by rulebook to low or no Nitro percentage on their fuels to car engines, who can run and are designed from the ground for the use with fuels with Nitro (trying to carb an engine running with no Nitro is a bitch to do...).
Nitro is vital and necessary for the chemical process that happens into the combustion chamber one of their actions is to give Oxygen and Hidrogen during the combustion, other less known is to slow the flame speed of the methanol burning, needed to control the explossion on the combustion chamber and help to give more power making the burning of the fuel and the explossion longer in time hence producing more overall power.
Let's see if we can shed more light on your comments.
Transfer height (linear measurement) determines timing on a 360 degree wheel. 164 degrees of total timing for the exhaust port determines a height on the exhaust port. If is ROAR legal or not is an issue that should not bother anything. When your engine is teched, the exhaust transfer height is measured on milimeters, not timing degrees and if is higher than 4.5mm, you're deemed illegal and you're out of race.
Reducing on 7mm the conrod lenght is a no no. Shortening the conrod makes to collide the piston skirt with the counterweight of the crankshaft and you need to remove more material from the piston (still, doubt if current pistons can accept to radical material remove) this piston will be weakened up to a point that will be unstable into the sleeve and will rock into the sleeve, scratching it and making it ovalized.
Marine mentality is fine for boats that only rely on high rpms to produce power not for cars that run on a closed track (probably are fine for tether cars or planes too), hence here their exagerated exhaust timings along to ultra-high compression ratios (or ultra small combustion chamber heights - name it as you prefeer) that rely on the extreme timing to control what occurs into the combustion chamber. As a plus, those engines run with a water cooling system, so their temperature never reaches the extreme temperatures you can find in a .12 engine with a closed body.
Edward, probably this is your worst problem, you're directly extrapolating what works on boats to cars, and this doesn't work on all cases. Some of your ideas are interesting, others don't apply, others simply... well.
Here, many people works and make 1:1 engines for a living (Engineers, motor builders, mechanics), others simply are gearheads (like me, have their own experience building their own engines, but their money is earned in other places), other simply rely on the experience of other people because they don't want headaches with engines.
Some of your advices aren't questionable are directly dangerous and harmful to people with light or no knowledge of our engines (0.008" of chamber height is a fine example, another is to make propaganda that for making power, the best is to reduce Nitro on their fuel).
If you're right, all the guys that run on Funny cars or other Top fuel categories are doing a complete nonsense burning a mixture of 90% nitro and 10% of Methanol, running 100% Methanol is much cheaper to run their multi hundred thousands cars burning thousands of dollars on each weekend they run.
On this last assumption, you're extrapolating what happens on FAI categories that are limited by rulebook to low or no Nitro percentage on their fuels to car engines, who can run and are designed from the ground for the use with fuels with Nitro (trying to carb an engine running with no Nitro is a bitch to do...).
Nitro is vital and necessary for the chemical process that happens into the combustion chamber one of their actions is to give Oxygen and Hidrogen during the combustion, other less known is to slow the flame speed of the methanol burning, needed to control the explossion on the combustion chamber and help to give more power making the burning of the fuel and the explossion longer in time hence producing more overall power.
Well this is the point about the rod-just to say it will hit counterweight and don't look for different design-it just nonsence. This is what called ordinary way. The second thing is I sad it is one of the ways to make timing for exhaust higher, but also I have mentioned there are more then that. It seems for me you are not interesting in it, so I will not go deeper.
About the real car, well I have slightly idea how the 4 cycle engine works, so I feel have no right to discuse them.
About marine mentality, well, did you ever run RC boat, FSR-V or FSR-H. If you did, you will know-we don't use there only TOP RPM, we have the same issues with panch and acceleration as well. The only difference is cooling. Well it is realy interesting point and can be dicuse forever. I have tested my motors on a lot of places around the world and nowhere people faced temp problem at all.
I sugested to try no nitro, yes I did, but before I sugested it, I tryed on my own engine and tortured very well. So I safe to say so, but again, if you never try don't say it will not work. Try and tell us what did you find, please!!!
About the power output. I would love to put my work on dyno but unfortunately I don't have one and don't know anybody who has it. I am sure i will find one iventualy and will do the test.
What do you mean is dangerouse to say you can run lower content Nitro with smaller head volume-is this dangerouse. I think more dangerouse to run 40% Nitro even with high head volume-Nitro is burning hotter, costs much more money etc.
Seems for me, like, you guys don't even want to try anything, beside what you did always. To move forward you need to be proactive and try a lot of stuff or one day it might be too late and can be way behind the line. I love to try, I am not afraid to work on engines, I am not afarid to experiment, but you can stay where you are right now, I have no problem with that at all.
So you stay on your way and I will stay on mine. But in the mean time I will put any post I want to here as long as I don't brake any rulls of forum. I think it is fair. I saw so much dangerouse info and can prove it easy by posting it, but will not do it. I just don't accepting it , that is all.
Have fun and run the hobby.
11-20-2003, 01:01 PM
#33
Originally posted by ziggy12345
I just talked to the guy who runs the local model shop and he says a good guide is to have 0.001" head clearance for every 1% nitro above 16% so 16% is 0.016" where 25% is 0.025"
Is this a good guide?
I just talked to the guy who runs the local model shop and he says a good guide is to have 0.001" head clearance for every 1% nitro above 16% so 16% is 0.016" where 25% is 0.025"
Is this a good guide?
11-20-2003, 02:12 PM
#34
Originally posted by Top Gun 777
if you never try don't say it will not work.
if you never try don't say it will not work.
11-20-2003, 02:24 PM
#35
Originally posted by Data
that sounds familiar, hey, where is my bottle of Smirnoff?
that sounds familiar, hey, where is my bottle of Smirnoff?
Jedi has a good memory !!!
Maybe TG will send the smirnoff once you're legal age?
I have a good memory too.
11-20-2003, 02:29 PM
#36
Originally posted by Data
that sounds familiar, hey, where is my bottle of Smirnoff?
that sounds familiar, hey, where is my bottle of Smirnoff?
Come for big race on KZ next weekend, I will give something better then Smirnoff.
Will you come?
11-20-2003, 02:32 PM
#37
Originally posted by Top Gun 777
Seems for me, like, you guys don't even want to try anything, beside what you did always. To move forward you need to be proactive and try a lot of stuff or one day it might be too late and can be way behind the line. I love to try, I am not afraid to work on engines, I am not afarid to experiment, but you can stay where you are right now, I have no problem with that at all.
Seems for me, like, you guys don't even want to try anything, beside what you did always. To move forward you need to be proactive and try a lot of stuff or one day it might be too late and can be way behind the line. I love to try, I am not afraid to work on engines, I am not afarid to experiment, but you can stay where you are right now, I have no problem with that at all.
11-20-2003, 02:34 PM
#38
Engine Shimming and Boost chambers
Does anyone know if a boost bottle/chamber are the same technology as shimming. Will using a boost bottle just expand the chamber just like adding shimms.
Is it good for the engine to use one?
Please advise.
Is it good for the engine to use one?
Please advise.
11-20-2003, 02:38 PM
#39
Originally posted by sparksy
that some bigger fish takes your ideas, and produces an engine that we will all buy. Its the nature of the beast. People want an engine from a brand that has a good history. Not a backyarder.
that some bigger fish takes your ideas, and produces an engine that we will all buy. Its the nature of the beast. People want an engine from a brand that has a good history. Not a backyarder.
and you will know you are running on somebodys good ideas. Don't worry about my money!
11-20-2003, 02:52 PM
#40
Originally posted by EVOLUTION
Maybe TG will send the smirnoff once you're legal age?
I have a good memory too.
Maybe TG will send the smirnoff once you're legal age?
I have a good memory too.
11-20-2003, 02:56 PM
#41
Originally posted by Top Gun 777
Hey, I was at CP many times and never see you there!!!
Come for big race on KZ next weekend, I will give something better then Smirnoff. Will you come?
Hey, I was at CP many times and never see you there!!!
Come for big race on KZ next weekend, I will give something better then Smirnoff.
Will you come?
11-20-2003, 03:05 PM
#42
tg
its not that your ideas are good bad or otherwise,some off them are quite good, it your general smugness that I find offensive, your attitude appears that your opinion is the only one that counts, period. I have no doubt that your an intelligent man, but the rest of us ain't stupid either. It appears you feel the rest of the world doesn't experiment therefore you figure we are ignorant. And don't blame it on you english, your attitude comes across loud and clear. I refuse to stoop to your tit for tat level, I just wont do it. The gentleman at the beginning of this thread asked a question and I gave him accurate information to put him in a position to have the opportunity to have some reliable fun. I didn't drag him off on some distant tangent that was designed to confuse him even more. But obviously your not happy unless you invade every discussion with the intent of making everyone else who might discuss anything about an engine look stupid. Its pitiful you feel the need to do that. you certainly have the right as this is america but I don't think your doing anyone any favors.
PS I'm not even going to reply to your 7mm shorter rod response as its just unrealistic and you know it.
its not that your ideas are good bad or otherwise,some off them are quite good, it your general smugness that I find offensive, your attitude appears that your opinion is the only one that counts, period. I have no doubt that your an intelligent man, but the rest of us ain't stupid either. It appears you feel the rest of the world doesn't experiment therefore you figure we are ignorant. And don't blame it on you english, your attitude comes across loud and clear. I refuse to stoop to your tit for tat level, I just wont do it. The gentleman at the beginning of this thread asked a question and I gave him accurate information to put him in a position to have the opportunity to have some reliable fun. I didn't drag him off on some distant tangent that was designed to confuse him even more. But obviously your not happy unless you invade every discussion with the intent of making everyone else who might discuss anything about an engine look stupid. Its pitiful you feel the need to do that. you certainly have the right as this is america but I don't think your doing anyone any favors.
PS I'm not even going to reply to your 7mm shorter rod response as its just unrealistic and you know it.
Last edited by Motorman; 11-20-2003 at 03:19 PM.
11-20-2003, 03:08 PM
#43
Originally posted by Data
you are confused about who is underage here.
you are confused about who is underage here.
11-20-2003, 03:37 PM
#44
Originally posted by Motorman
tg
its not that your ideas are good bad or otherwise,some off them are quite good, it your general smugness that I find offensive, your attitude appears that your opinion is the only one that counts, period. I have no doubt that your an intelligent man, but the rest of us ain't stupid either. It appears you feel the rest of the world doesn't experiment therefore you figure we are ignorant. And don't blame it on you english, your attitude comes across loud and clear. I refuse to stoop to your tit for tat level, I just wont do it. The gentleman at the beginning of this thread asked a question and I gave him accurate information to put him in a position to have the opportunity to have some reliable fun. I didn't drag him off on some distant tangent that was designed to confuse him even more. But obviously your not happy unless you invade every discussion with the intent of making everyone else who might discuss anything about an engine look stupid. Its pitiful you feel the need to do that. you certainly have the right as this is america but I don't think your doing anyone any favors.
PS I'm not even going to reply to your 7mm shorter rod response as its just unrealistic and you know it.
tg
its not that your ideas are good bad or otherwise,some off them are quite good, it your general smugness that I find offensive, your attitude appears that your opinion is the only one that counts, period. I have no doubt that your an intelligent man, but the rest of us ain't stupid either. It appears you feel the rest of the world doesn't experiment therefore you figure we are ignorant. And don't blame it on you english, your attitude comes across loud and clear. I refuse to stoop to your tit for tat level, I just wont do it. The gentleman at the beginning of this thread asked a question and I gave him accurate information to put him in a position to have the opportunity to have some reliable fun. I didn't drag him off on some distant tangent that was designed to confuse him even more. But obviously your not happy unless you invade every discussion with the intent of making everyone else who might discuss anything about an engine look stupid. Its pitiful you feel the need to do that. you certainly have the right as this is america but I don't think your doing anyone any favors.
PS I'm not even going to reply to your 7mm shorter rod response as its just unrealistic and you know it.
if you read my posts in this particular thread, you will understand that you are just playing the words. my first post say what I use on my P/S sets , my second post began "I sugest.." So where did you find, that where I sad my ideas is the best? You sad you can pull more power then I can, but even make this statment without seeing my work is nonsence and you know this very well. You are acting here as the "Man" and the rest are just backyarders.
The racer who start this thread didn't ask particularly you, he ask everybody. You felt it is your responsobility to give him some accurate advice and I felt I can add some other opinion. But because my opinion isn't the same as yours, I am already enemy. every time when someone sas something which is not what you think is enemy for everybody. Do you think you can blame people for having their own opinion and sharing it with everybody? I didn't push anybody , I just sad what I am doing and what I am sugesting-and it is already wrong and I am melting somebody's hardware.
About 7mm-it is not 7 , it is 8 mm shorter.
11-20-2003, 04:04 PM
#45
call it what you want. I could have posted it differently.
I did not edit my post for being aggressive you did. I stick by what I type. or I wouldn't say it.
I certainly am not the man, it appears you are.
Enemies I have my share but I don't think I ever said you were one of them, you are making that statement.
I await your next dig at me, however you wont get a response.
I did not edit my post for being aggressive you did. I stick by what I type. or I wouldn't say it.
I certainly am not the man, it appears you are.
Enemies I have my share but I don't think I ever said you were one of them, you are making that statement.
I await your next dig at me, however you wont get a response.