silent choice?
06-05-2003, 12:19 PM
#21
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Here's how the corsa switchable diverters work. They are shut in the off position diverting exhaust thru the prop. If you have electrical failure they are going to run thru the prop. The guts are all steel. I know because I dropped in 500hp's in my boat and had to sell all my exhaust because of the different riser angles. The switchable diverters for my 500hp are setup open thru transom with no electric to them and the selonoid holds the steel flapper shut to divert thru prop.
With my 454 before I have run pretty hard with the diverters closed for thru prop and no problems. If you look closely there is a steel rod down thru the diverter to stop the flapper from going too far and damaging the selonoid. Thats the little knob you see on your diverter.
With my 454 before I have run pretty hard with the diverters closed for thru prop and no problems. If you look closely there is a steel rod down thru the diverter to stop the flapper from going too far and damaging the selonoid. Thats the little knob you see on your diverter.
06-05-2003, 03:39 PM
#23
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Jumping a little here back to the question about what really happens when you go above some 2000-3000 rpm with silent choice directed through the prop. As you say, the reversion should be greater at lower rpm. I dont think the exhaust pressure will open the ports to the transom pipes , but if they do that will not cause any damage. So what is the problem? Will the cooling water flood the exhaust or will the engine overheat ? Or will it only hurt performance?
06-05-2003, 04:32 PM
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You are going to loose performance if you have the exhaust through the prop at higher rpm.
Think of an engine as an air pump in this case. The more air you are pushing through the more power you can make. To increase air (HP) you change air filters, port and polish intake maninfolds and if thats not enough bolt on a supercharger, lots more air. To get the air out you port polish and bolt on exhaust systems to let the air flow out. Any restriction at either end of the motor is going to hurt performance. With a stock motor, mechanicaly you should be ok though, merc sells this set-up in many boats.
If you run a supercharged motor with a closed exhaust you will back up the system to the piont where you will do major damge to the motor.
Think of an engine as an air pump in this case. The more air you are pushing through the more power you can make. To increase air (HP) you change air filters, port and polish intake maninfolds and if thats not enough bolt on a supercharger, lots more air. To get the air out you port polish and bolt on exhaust systems to let the air flow out. Any restriction at either end of the motor is going to hurt performance. With a stock motor, mechanicaly you should be ok though, merc sells this set-up in many boats.
If you run a supercharged motor with a closed exhaust you will back up the system to the piont where you will do major damge to the motor.
Last edited by Tantrum; 06-05-2003 at 04:38 PM.
