Exhaust Help
05-21-2018 | 10:04 AM
#12
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From: Hemlock, MI
05-21-2018 | 10:16 AM
#13
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From: Detroit, MI
If you can't find what you're looking for, for sale off the shelf I can make you whatever you need. I own a small machine shop...
Either way I wouldn't run those risers now that you cut the flange off of them.
Either way I wouldn't run those risers now that you cut the flange off of them.
05-21-2018 | 06:24 PM
#17
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From: Arizona
05-21-2018 | 06:30 PM
#18
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From: Possum Kingdom
I even started to burn through a set of the silicone tubes before I cut the beveled part of the risers off . The exhaust gasses are obviously really fukin hot !
Hopefully the new taller risers will fix this issue. Im still not sure though how taller risers cuts down on reversion. Maybe just harder for the engine to draw water up that much higher ?
Last edited by jryotas; 05-21-2018 at 06:33 PM.
05-21-2018 | 06:58 PM
#19
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From: Detroit, MI
Well , best I can tell it burned through due to mis-alignment and the fact that the exhaust gasses were basically dumping downward onto the tubes with little room for cooling to happen.
I even started to burn through a set of the silicone tubes before I cut the beveled part of the risers off . The exhaust gasses are obviously really fukin hot !
Hopefully the new taller risers will fix this issue. Im still not sure though how taller risers cuts down on reversion. Maybe just harder for the engine to draw water up that much higher ?
I even started to burn through a set of the silicone tubes before I cut the beveled part of the risers off . The exhaust gasses are obviously really fukin hot !
Hopefully the new taller risers will fix this issue. Im still not sure though how taller risers cuts down on reversion. Maybe just harder for the engine to draw water up that much higher ?
in other words 3 inch taller + steeper angle = same exit point
05-21-2018 | 08:49 PM
#20
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From: On A Dirt Floor
So I installed a set of emi manifolds and risers on my gen vi 502 mag mpi. Had some alignment issues and I kept burning up exhaust tubes due to the exhaust gasses exiting pointed at the wall of the tubes , not out the back of the boat. Even tried the high $ silicone tubes . Finally ended up running an extra piece of stainless between the riser and tips in the transom. I also ended up cutting the flange off the risers to help correct the angle issue, about .5" was cut off . Im a lil worried about reversion. I assume that is the reason for the flange on the end of the risers?
So now im not burning up exhaust tubes but am now noticing a miss if I idle for more than a couple minutes. The miss goes away of I rev up a little. Should I have a muffler shop add a lil flange to the end of my risers? I have replaced the spark plugs and there was no signs of water.
I would post pics but seem to have not hit my 10th post yet ):
So now im not burning up exhaust tubes but am now noticing a miss if I idle for more than a couple minutes. The miss goes away of I rev up a little. Should I have a muffler shop add a lil flange to the end of my risers? I have replaced the spark plugs and there was no signs of water.
I would post pics but seem to have not hit my 10th post yet ):
