40' Outlaw Upgrades - Twin 900Sc to 1000hp Duramax Diesels
#31
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This might help your gear ratio issue on a glide based transmission. http://www.jegs.com/i/Sonnax/852/28158G-06SP/10002/-1. They are supposed to hold 2500hp+ with a 3,000 load. (drag race application)
#32
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Thread Starter
Thanks Speed. I'll fwd that over to Coan and see what he says.
#33
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Just out of curiosity what's your expected power loss through your gearbox and drives? I know dry sump #6 is around 10%
Last edited by 999JAY; 08-28-2016 at 11:32 AM.
#34
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Thread Starter
That's a great question for Shifter since they're his design. But he hasn't been online in a good while.. What ya have is a 2 or 3 straight cut gear set transfer case, driveshaft fed into a vertical 5 sack of smaller straight cut gears inside the actual dives. The upper primary gear cases are dry sump, but the lower units are not. Those are filled with like a 70 weight oil. Since there's no vertical shafts or pinions involved, I bet it's well under 10% loss. Very similar to the Arneson drop box setup, but without a chain.
I will say these lowers spin easier than any Merc I've spun before. And with less backlash than you'd expect on 8 gears meshed up. I was checking that out yesterday when draining them to be sent off to paint. But the main selling point was that 2000lb ft rating you just don't see in any other drive of the size. When dealing with big torque, options are less than limited..
[ATTACH=CONFIG]558709[/ATTACH]
I will say these lowers spin easier than any Merc I've spun before. And with less backlash than you'd expect on 8 gears meshed up. I was checking that out yesterday when draining them to be sent off to paint. But the main selling point was that 2000lb ft rating you just don't see in any other drive of the size. When dealing with big torque, options are less than limited..
[ATTACH=CONFIG]558709[/ATTACH]
Last edited by kidturbo; 08-27-2016 at 03:19 AM.
#35
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Certainly a beefy looking unit, 7+ gears I would imagine at least 40hp to drive it at max rpm, what weight is the unit with the transfer case and extension box.
Any idea what loss you will see in the transmission? I tried to find out what it would take to drive my ZF units but couldn't get any information.
Did you investigate the SCS dropbox as an option? the 14" drop was to great for my application, but it a great piece of engineering.
Any idea what loss you will see in the transmission? I tried to find out what it would take to drive my ZF units but couldn't get any information.
Did you investigate the SCS dropbox as an option? the 14" drop was to great for my application, but it a great piece of engineering.
#37
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I have been through all of these headaches you are experiencing trying to get my engines as low as possible.
I ditched the BBC offshore engine mounts and fabricated aluminium channel for the outboards mounts and fabricated large aluminium hanging brackets bonded to the tunnel for the inboard side as I didn’t want to drill mounting bolts through the inside of the tunnel .This enabled me to mount everything cleanly without compromising the strength of the tunnel itself and allowed the engines to sit as low as possible.
I still didn’t get them as low as I wanted as the ZF305 has a sump that is 6” lower than the output centreline, causing my X to be 2-3 higher than I would like.
One consolation is that my drivers are sitting on a ten extension boxes and the BPM stern tube is 6” longer than a regular Arneson so my prop is 16” further back than a regular setup, my props are running in cleaner higher water.
I thought I would try the setup out before make any further alterations, worst case scenario if the X turns out to be too high is to run ASD8-6 boxes.
Are you running solid or shear mounts? I went for shear but we will see how they perform.
I ditched the BBC offshore engine mounts and fabricated aluminium channel for the outboards mounts and fabricated large aluminium hanging brackets bonded to the tunnel for the inboard side as I didn’t want to drill mounting bolts through the inside of the tunnel .This enabled me to mount everything cleanly without compromising the strength of the tunnel itself and allowed the engines to sit as low as possible.
I still didn’t get them as low as I wanted as the ZF305 has a sump that is 6” lower than the output centreline, causing my X to be 2-3 higher than I would like.
One consolation is that my drivers are sitting on a ten extension boxes and the BPM stern tube is 6” longer than a regular Arneson so my prop is 16” further back than a regular setup, my props are running in cleaner higher water.
I thought I would try the setup out before make any further alterations, worst case scenario if the X turns out to be too high is to run ASD8-6 boxes.
Are you running solid or shear mounts? I went for shear but we will see how they perform.
You're engine mounts look almost the same as mine Only I use offshore style and have long aluminum l shape brackets on both stringers so I can shift my engine forth and back to change weight for cg point .
Ken ,
Keep the pics coming and we keep texting till the baby is done ! We might schedule a first water test party whit all guys involved in the R&D department here ! LOL
#38
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Bor I might try and pull a thread together I haven't done on yet for this build.
I changed my out board mounts to full length aluminum L section, sorry I didn't have a photo handy to post at the time.
I changed my out board mounts to full length aluminum L section, sorry I didn't have a photo handy to post at the time.
#40
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Thread Starter
Also ran into Shifter by chance at a race yesterday. Learned more about these drives. I was mistaken above when I said these lowers were not dry sumps. There is actually a pump and reservoir tucked away in back half of those units.
Last edited by kidturbo; 08-29-2016 at 01:20 AM.