Completed "Thru-thunder" swim platform modification
 

I completed my "Thru-thunder" swim platform modification
if you recall, I trashed my swim platform due to a "rambunctious" photo session. so we repaired the platform and i decidd to fab thru hull extension to carry the exhause all the way to the square tips.

Waterfoul will now post the pics, as I don't have the paid membership.... :rolleyes:

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

The root cause and the result

Re: Completed "Thru-thunder" swim platform modification
 

The repair

Re: Completed "Thru-thunder" swim platform modification
 

The thru-thunder product improvement

Re: Completed "Thru-thunder" swim platform modification
 

nicw job, did you have any damage to the transom?

Re: Completed "Thru-thunder" swim platform modification
 

Rambunctious-

How did this modification work? I am thinking about doing the same thing. How much louder is at idle?

Thanks
Don

Re: Completed "Thru-thunder" swim platform modification
 

NICE looking deal. Let us know how it sounds. I've given thought to the same thing , just no time to engineer it , then DO it :( .

Re: Completed "Thru-thunder" swim platform modification
 

No damage to the transom. they are just through holes for the U bolts.

I fired the boat up this weekend in the driveway after getting everything ready for spring here in Michigan.

it is louder at idle. sounds good, wish i had a good cam in those stock 330's though :D
the water really flapps the rubber ....um... flaps..... :D . I think they were a little more dampened the old way with the volume of the silent thunder box.

when i fired the second engine up. noticed my drive inicator
( dumb merc volt guages) showed a funny location so i cycled the drive up and down. Well, that engine sounded SWEET!!!!!!! till i realized i was running dry exhaust due to the earmuffs falling off the drive ( how stupid) :rolleyes:

shut her down at 200 deg F !!!!! when i realized what i did and put the water back on right away and started and cooled here back down.

no damage to exhaust hoses, but i hope i did not burn the impellor. That is the absolute worst job in a 272. with your feet straight up in the air.!!!! been there , done that....

so. we will watch it on the first run in 10 days. our first boat club run on lake michigan for the season.

but it does sound nice. no different that any other boat with thru hulls and no cans.... but definitely louder than silent thunder. I don't expect any performance improvement, just sound...

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

Nice!!!!!!!!!!!!

Re: Completed "Thru-thunder" swim platform modification
 

nice job Ram!!! best of luck with the impeller!

Re: Completed "Thru-thunder" swim platform modification
 

I don't want to be a voice of "the black cloud of doom and gloom" but if you've got a run coming up I'd check that impeller. I burned one of mine up in less than 40 seconds when one of my "earmuffs" fell off and it only went to 180 degrees, then I got a pair that has the wire that goes through the drive inlets and don't have that worry anymore. If it went to 200 degress, I'm betting you've got damage. Sorry.....

Re: Completed "Thru-thunder" swim platform modification
 

I agree with Formula. Take the time to hand upside down now of you will probably miss the run. If you pull it apart now it will of course be fine and you will just be pissed you spent all that time doing it for nothing :rolleyes: :rolleyes:

You want a hard one to do try my 18 Donzi with a 454 in it while you have a hang over :eek: :eek: All to find out the water pump was fine :drink: :drink:

Re: Completed "Thru-thunder" swim platform modification
 

Yea, I know. I will prolly end up checking it out.

the last time I changed an impellor I had a sinus cold. I could NOT stand it. every time my head was below my heart it about exploded. i would come up for air and my face was absolute beat red. i think i chucked a few wrenches that time.

but i am getting faster at this. and i have the strings and hooked wires hanging in the barn ( specialty tools)

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

Ya to do the Donzi you have to do it all by feel for the most part. I have used my digital camera before to see what I was doing..... IT SUCKS

Jon

Re: Completed "Thru-thunder" swim platform modification
 

Been there!!! A buddy of mine ran his Baja accross a sand bar last year at the Emerald Coast PR. After consuming many adult beverages I offered to flush the sand out of the engine the following morning. Nothing like standing on your head with alcohol poisoning, 95 degree heat and 100% humidity!! I thought I was going to die. It always makes a great story around the campfire, though. Boats - what a freakin blast they are! :evilb:

DO check that impeller. I have definitely burned them up in a hurry. There are at least 3 things everyone that has owned a boat for any period of time has done:
1) Leave the plug loose/out
2) Accidently pull the kill lanyard loose and almost ran the battery dead trying to start it.
3) Burned up an impeller by doing something :rolleyes: unintelligent!

Re: Completed "Thru-thunder" swim platform modification
 

Rambuntious,

Have you had the boat out on the water for a "sound and performance" check after the mods to the exhaust?

Let us know...

Re: Completed "Thru-thunder" swim platform modification
 

the sound is great!! idle is louder but not obnoxious at all.

coming on plane sounds sweet under heavy load, once we top out it definietly sounds better, can hear there is more crisp sound but not too loud at all

we are making a video and the buddies taping said it sounds so much better.... and the wife didn't complain at all this weekend.

friends noticed, wife doesn't care...... perfect :evilb:

as far as performance.... no gain... as expected.....
but sounds faster :D so money....and time........ well spent

now, to finish the 3 step buffing/polishing/waxing of that dang black gel coat..... and i will finally be on top of this boat for the season......

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

oh...and after a 5 HOUR PROJECT!!!!!! the impellor was just fine ARGGGGG. boat is for sale.... every time i do that job, the boat is for sale. either that or i need double jointed elbows because when you put your arms over the back seat liner, your eyes are behind the front plane of the engine.

wife was in the house giving the kids a bath and she could hear my cussing and screaming and chucking of tools and stuff.......


but ,, peace of mind now. ( not then... that's for sure) :o)

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

SO RAMB,

Did you keep the templates to hook your OSO bro's up? :D

I would be willing to contribute to your boat fund :D :D

mtgbiker

Re: Completed "Thru-thunder" swim platform modification
 

boat fund??? you wanna buy my boat??? or blue prints for the exhaust :D

I have to see if i kept the final dimensions on the exhaust hose lengths... the other metal parts i have dimensions ...somewhere in the pole barn.......hm.............

the trickiest parts were the round to rectangular ends. cost me two dinners with drink for my model shop buddies at work. luckily they were actually taking a welding class and were on stainless steel at the right time.... !!!!!

ramb

Re: Completed "Thru-thunder" swim platform modification
 

for those that wanted to know what it sounds like.

check out my video i jsut finished. it will tell you.

so, TURN IT UP !!!!
after going to this link, right click under the icon and choose "open in new window"

Rambunctious Video

Re: Completed "Thru-thunder" swim platform modification
 

Way cool video man :cool:
If you want another project , check out these Johnson crank mounted sea water pumps on my 272 with 540s.
The impeller is a 15 minute job and that includes searching for the spare that you put away somewhere :D
Plus the fact I now have two less belts to worry about too :)

Re: Completed "Thru-thunder" swim platform modification
 

Very nice that should keep some of the winter blues away, the boat sounded great. :D

Now if we could get Mopower to do a small video with those 540`s :D

Re: Completed "Thru-thunder" swim platform modification
 

Great Video !!! I'm gonna save a copy to watch in February when there's 2 feet of ice on Lake St Clair.

Re: Completed "Thru-thunder" swim platform modification
 

I was out today for lunch 74* and sunny. May have been my last time as my power winch kinda took a dump. Still have my orig. hand winch but that sugs.

And I'll tell you what...with those 540s ya gotta sit down , shut up , and hold on :D :D. Unless of course I had a video from another boat perhaps ;)

Re: Completed "Thru-thunder" swim platform modification
 

Well I saw Rambunctious video and I knew my platform was coming off. Well it was such a nice day and only a few bolts away, why not go for it. Not a bad job for two people.

My next question is what size plywood did you use marine of course 1/2 inch? I was searching around for some ideas for the exhaust and I found that Dana marine had flexabile exhaust hose $1.75 PER INCH :eek: . I think I can have a stainless piece made for the exhaust outlet.

what do you think?

Re: Completed "Thru-thunder" swim platform modification
 

Me too! Except my platform's staying off.
I blame Formula Outlaw :D :D
Before
http://www.mattyorke.co.uk/albums/re...0043.sized.jpg
After
http://www.mattyorke.co.uk/albums/23...0781.sized.jpg

Re: Completed "Thru-thunder" swim platform modification
 

I think it was 3/4" marine. not sure. I would not skimp on the wood thickness if you go through the trouble of rebuilding , since the plywood is the failing part. Look at my pic again to estimate the thickness... but seems like 3/4". I had the work done by my local marine guy so i did not spec the material thickness myself.....

It is strong now !!!

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

I resemble that remark....:drink: :drink:

LOOKS #@(*#!G GREAT.......:drink: :drink:

Re: Completed "Thru-thunder" swim platform modification
 

TTT For the Great Video:D

Re: Completed "Thru-thunder" swim platform modification
 

Should have sold it to me when you had the chance. Now look at the mess I'm in.

Re: Completed "Thru-thunder" swim platform modification
 

Ram.... I wonder if this mod would help on a 357sr1 with 502's

Re: Completed "Thru-thunder" swim platform modification
 

This is Rambunctious here logged on at Waterfoul's
I can't seem to post right now under my logon.....??

there was no performance improvement, as expected. i wanted to eliminate th rattling of the loose baffles, and make it a little louder , since i had the swim platform off anyway.

so... it sounds great and I am glad i did it.
someone mentioned corrogated exhaust ??
One fellow performance boater told me that the corrogated exhaust hose is restricting. I don't have any data, I used smooth hose with stainless 30 deg elbows we fabricated to make the zigzag in the outboard chambers.

Ramb

Re: Completed "Thru-thunder" swim platform modification
 

So in other words it would be a waste of time for me to do it for a 357 when there is no performance gain. 357sr1man

Re: Completed "Thru-thunder" swim platform modification
 

This is for 87 formula looking do do some exhaust work

Re: Completed "Thru-thunder" swim platform modification
 

Thanks Masi-I think my platform is the same as the ones I have seen here-just no holes in it. It seems that simple...hopefully it is. I think I will keep gathering info and parts and try tackling it this winter.