Anyone used a steel geared intermediate shaft?
#1
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I'm assembling a 930 and have a choice between the original aluminum geared intermediate shaft and a steel geared shaft. The crank has the matching gear for the steel gear already installed. Has anyone used the steel geared option? Anything I should be aware of? Many thanks,
mpp
mpp
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Make sure the 2 gears are a matched pair. Also check the gear backlash. straight cut gears require a different setup than the stock type. Make sure you check the gear shaft for been straight. I had one and the shaft was bent and the gear lost its backlash when turned. Have them Magnufluxed to check for cracks. Expect more noise, but 20HP?
Hmmmm. Sounds like a sales pitch to me. Forget the HP, go for the accuracy if the gear set is good.
Hmmmm. Sounds like a sales pitch to me. Forget the HP, go for the accuracy if the gear set is good.
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The 20hp statement was not by JB racing. This is info that has been seen on the dyno. No sales pitch here... just info coming straight from the engine builder of the fastest porsche in the world in the quarter mile. I did not get into specifics of what combos they have seen these results with. The gears are $1125 dollars a set so I do think that is a quite expensive for what it is.
Last edited by Strokher Racing; 02-18-2013 at 12:10 PM.
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Interesting. The steel set I have are NOT the > $1000 kind as far as I can tell. I think it may have come off of a 964 but don't know for sure (bought the engine already apart with many modified parts). The gear teeth are set at an angle like on the aluminum set but there are more teeth on the wheel (obviously the steel is stronger and can support finer teeth). I would suspect the advantages would be quieter operation and less wear over time. I'm really blanking on how it would change the horsepower: substantially easier to turn? more precise cam/chain control?
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Eric is stating that using straight cut gears somebody had a 20bhp increase. I can see this is probably true if the engine was kicking out around 900bhp.
Sameer, the straight cut gears inside the engine means no energy is wasted pushing the shafts backward and forwards like the helical's would. This is causing extra friction and therefore would cause more drag/friction and thefore absorb energy. Downside is noise. Would be nice to hear what it is like from inside the car. Maybe it would be quite nice.
Sameer, the straight cut gears inside the engine means no energy is wasted pushing the shafts backward and forwards like the helical's would. This is causing extra friction and therefore would cause more drag/friction and thefore absorb energy. Downside is noise. Would be nice to hear what it is like from inside the car. Maybe it would be quite nice.