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Discussion Starter #1
I know it is here some where but My searches have come up empty.

How thick should an engine plate be, 3/8" or 1/2"?

Is there a specific width and thickness for the rails? Is 2" x 2" x 3/8" ok for rails? Thanks.....Hal
 

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ONE PIECE (stringer to stringer) 3/8", 6061-T6.
Yup, what George said. This is what mine are as well. I think I covered it on my project page somewhere.
How you been Hal?


I also used 2" flat bar on the outside of the stringers to backup the rails and used 3/8" bolts. I drilled the holes 2" from the ends and then split the difference betweem them. On mine it came out to be 10" between the bolts and I have 5 or 6 bolts per side (can't remember for sure).

Take care.......john
 

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3/8" is fine. one piece is most common for the back. two piece is preferrable for the front like this.
 

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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
 

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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
Wow....... I think you might have an uphill battle on this one. But hey I guess I don't know anything about rigging, nor do quite a few other peeps on here.
 

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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
no offence sir, but if a stringer fails with a two piece attached to it then the boat has bigger problems than the motor mount design.

1 inch stringers in a boat that gets beat on like it owes me money at the river and the race track:



I know quite a few people using the same mounting system in 30 year old boats without issue.
 

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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
please show some pics of how everyone should do it o wise one.
 

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Amber Racing Services
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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
I guess most of the race boats out there on the NJBA & IHBA circuits dont understand how rigging is supposed to be done.

2 piece front motor plates are very common all the way from River Racer to Top Fuel ... hmmm :)sphss
 

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C'mon now, this guy has been building engines, rigging boats and giving advise for over 25 years. He must know what he is talking about with a statement like that....:)sphss


Maybe he should get back to the open water and rent his ring. :)gay:(
 

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Spreading out the stresses is why you run "motor rails and plates". To use big ol' heavy BS TWO PIECE front plates shows just how little some people know about race/play boat rigging. I suggest you use ONLY the lower four BLOCK bolts and make it a ONE PIECE UNIT! SAVE some weight and save the stringers at the same time. The over weight mounts shown do not support the stringers and could come loose and or damage the stringers. "Some things LOOK GOOD, but others LOOK GOOD AND LAST A LONG TIME!" Well those two piece plates do work well ON THE TRAILER! If you are going to use the boat, ONE PIECE PLATE, if you are going to 'jack off in the garage' do the "two piece deal" it will last longer there.
Only if someone forgets to tighten the bolts that bolt the plates to the motor.

I hear 300lb chunks of cast iron tend to make decent structural members....I fail to see why a 2 piece design would be any weaker than a one piece. Remember, if the bolts are properly torqued and one uses the correct washers, the bolts are acting in tension, not in shear....so it makes no difference.
 

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Finishline......How do you figure a one piece plate is going to save weight over a two piece set up? Let's see some pics of your rigging jobs since they are obviously superior to the pics posted of the 1000+ HP boats that run 130 mph at the track one weekend and then run up and down the river the very next weekend.
 

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Finishline......How do you figure a one piece plate is going to save weight over a two piece set up? Let's see some pics of your rigging jobs since they are obviously superior to the pics posted of the 1000+ HP boats that run a 130 mph at the track one weekend and then run up and down the river the very next weekend.
lightening holes
 

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Amber Racing Services
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Finishline......How do you figure a one piece plate is going to save weight over a two piece set up?
A one piece with more material would not be lighter.

lbhsbz said:
I fail to see why a 2 piece design would be any weaker than a one piece.
A two piece would not be any weaker. The block is not going to flex and the extra material isn't needed that makes it a one piece.

While the ones that Kjell (widowmaker) posted a picture of had extra material that could be removed ... it's design is excellent for front plates, using the 4 block holes and 4 water jacket holes.

A lot of racers and well known marine shops who rig race boats utilize the 2 piece design and they aren't 'jacking off in the garage'.

BB
 

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÷קmᮆÚš×÷;698119 said:
cmon guys its George from Finishline boats he knows it alllll.. NOT!!!
:D That guy was always bad mouthing me about Smiley and the southwind 20. Maybe he wants to bad mouth the SWTD too......HAAA
 

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Discussion Starter #20
Rail Thickness

I know the standard thickness for the rails are 1/4" but is there any reason 3/8" Thick rails could not be used.
Is it just overkill and more $$$?
I have some length of 2 "x 2" x 3/8". Would this not work just as well?...H
 
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