scc project silvia potato....turbo lag?
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scc project silvia potato....turbo lag?
ok, so I've been pondering this article 'behold the potato' from the june scc...
my question is this...is most turbo lag brought about by the significant lengths of ic piping? or did they eliminate it by putting in that newer turbo? or a combination of both...
I'd be quite interested in trying out the ic setup like the one they had in their project silvia with my ka, but if it's not the factor, that kindof eliminates the purpose.
thanks
-Alden
my question is this...is most turbo lag brought about by the significant lengths of ic piping? or did they eliminate it by putting in that newer turbo? or a combination of both...
I'd be quite interested in trying out the ic setup like the one they had in their project silvia with my ka, but if it's not the factor, that kindof eliminates the purpose.
thanks
-Alden
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Turbo lag is the composite of many variables such as:
Turbine wheel size/trim
Turbine housing AR size
Downpipe diameter
Boost controller type
Length of IC piping
Diameter of IC piping
Type/size of IC
Compression ratio
Air/Fuel ratio
Turbo Center cartridge type
best thing to do is, Keep your IC pipes down to a reasonable size, like 2.25-2.5" max and the shortest distance w/ as few transitions and bends as possible.
Dont go overboard and get a HUGE as FMIC when a smaller one will do the trick. I prefer top-to-bottom over a side-to-side. for the same size core dimensions, a top to bottom will have more paths for air to flow and create less pressure drop since the internal paths wont be as long either.
Get a big turbine wheel, and a small AR size on the turbine housing. a 2.0L w/ a .48 AR exhaust spools VERY fast, especially w/ a 8.5:1 compression, cuz thats about what our DSM has, and the boost comes on instantly. so it would be a little more smooth on a smaller engine at the same CR. an exahust in the 50's AR would be better for street use.
a Ball bearing center will make your boost come on faster by a few hundred RPM by itself, but the time it takes for that boost to reach the engine, is all controlled by the IC and pipes.
basically, if your IC and pipes are huge, its like blowing into a cave and trying to pressurize it. You have to pressurize the IC and pipes before the pressure hits the engine... so the less pipe and IC volume there is to pressurize, the FASTER that pressure will hit the engine.
a leaner A/F ratio will make hotter exhaust w/ more energy which will put more force on the turbine and spool it quicker... it may not be significant, but all the little things add up. its a means to an end.
Turbine wheel size/trim
Turbine housing AR size
Downpipe diameter
Boost controller type
Length of IC piping
Diameter of IC piping
Type/size of IC
Compression ratio
Air/Fuel ratio
Turbo Center cartridge type
best thing to do is, Keep your IC pipes down to a reasonable size, like 2.25-2.5" max and the shortest distance w/ as few transitions and bends as possible.
Dont go overboard and get a HUGE as FMIC when a smaller one will do the trick. I prefer top-to-bottom over a side-to-side. for the same size core dimensions, a top to bottom will have more paths for air to flow and create less pressure drop since the internal paths wont be as long either.
Get a big turbine wheel, and a small AR size on the turbine housing. a 2.0L w/ a .48 AR exhaust spools VERY fast, especially w/ a 8.5:1 compression, cuz thats about what our DSM has, and the boost comes on instantly. so it would be a little more smooth on a smaller engine at the same CR. an exahust in the 50's AR would be better for street use.
a Ball bearing center will make your boost come on faster by a few hundred RPM by itself, but the time it takes for that boost to reach the engine, is all controlled by the IC and pipes.
basically, if your IC and pipes are huge, its like blowing into a cave and trying to pressurize it. You have to pressurize the IC and pipes before the pressure hits the engine... so the less pipe and IC volume there is to pressurize, the FASTER that pressure will hit the engine.
a leaner A/F ratio will make hotter exhaust w/ more energy which will put more force on the turbine and spool it quicker... it may not be significant, but all the little things add up. its a means to an end.
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a leaner air fuel ratio will make a hotter egt up until 14.7:1 where it will then get much lower
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rest in peace tim.
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rest in peace tim.
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yup, indeed. hotter is not always better... stay away from anything over 1500*F, measured 1.5" away from exhaust port. any higher than that, and your liable to break sumfin
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