cutting down mid

[mad man]

How does a guy go about cutting a mid down ? Can you just open up the back to relieve exaust ?

[Raceman]

You're talking about 2 different things here. Cutting down a mid usually refers to shortening the height. Most common dimensions are cutting a 20" down to either 15 or 16 inches. Some of the transom bracket assembiles are very difficult to cut all the way to 15, so that's the reason for the 16's.

Relieving the exhast can be accomplished in several ways. Any time you drill holes in a standard mid you are weakening it and making it more prone to breaking off. The old Merc high perf mids (non-offshore type were drilled in the bottom of the fat part, with several half inch holes in each side. This directed the exhaust down toward the water, but made it significantly louder, and on some boats easier to get on top. I've seen one Merc factory mid fail, and heard of several others. Some people drill holes in the rear of the mid. This is the highest stress area, so is more prone to failure.

Relieving the exhaust serves several purposes.

1. Helps some boats jump on top easier
2. Annoys neighbors or other people in conjested areas
3. Attracts attention of law enforcement

What it DOES NOT do is add any performance.

[mad man]

Thanks raceman Just testing the waters to see how I can get a little more out of stuff I already have .To make my new mod vp what I want . Tight on funds rht now. Where can I get some info on cutting down a mid ??

[Tom Foley]

There is a lot to it in terms of maintaining alignment , edge prep for welding , the welding process and integrity of the welds etc . Any misalignment of the drive shaft and powerhead could lead to expensive repairs . If you have extensive experience in welding and fabrication I'm sure you could do it with some fixturing . honestly though I'd doubt you would see any real world gains from just shortening your mid .

Marty Powell here in st Pete does tremendous work .

[twig]

Thats a brave user name!!!

There was once a great man that went by that name!!

[Ranger976]

There is a lot to it in terms of maintaining alignment , edge prep for welding , the welding process and integrity of the welds etc . Any misalignment of the drive shaft and powerhead could lead to expensive repairs . If you have extensive experience in welding and fabrication I'm sure you could do it with some fixturing . honestly though I'd doubt you would see any real world gains from just shortening your mid .

Marty Powell here in st Pete does tremendous work .

Marty, did mine awhile back ...his work is second to none....Good luck Jim

[motorheadbishop]

Marty, did mine awhile back ...his work is second to none....Good luck Jim
:iagree:and he has mine right now...
Doin sum thin a little trick this time
and it should be BAD 2 THE BONE!!!!:thumbsup:

[motion]

its not too bad, here is the detailed and best way to shorten your mid, take it off boat, disassemble the powerhead from the mid, remove the can from the clamp bracket, and disassemble clamp bracket, the next step is the most critical, send the apropriate pieces to marty powell and have them shortened, then put it all back together , good luck

[Dave S]

Send to the best person ya can. It is crittical to ya health.:eek:

[Black Lightning]

In my opinion I would look at it like this. Im sure that the people who do this do great work, but and this is a big but....a chain is only as strong as its weakest link. Same goes for a cut mid. How much is your life and the life of those around you worth? If it was mine Id rather spend and get a cast piece from Mercury or Mad EFI..

[Markus]

Thats a brave user name!!!

There was once a great man that went by that name!!

Wayne used madman with no space.