Grog

Formula guys -

I did some searching in this forum and couldn't find anything on the subject so I'll ask......

How much does the Silent Thunder box on my 1999 271 Fastech weigh? This is probably a baaaaad idea but I am thinking about removing it if the weight is significant.

Thanks,
Greg

offthefront

iTrader: (1)

I would say 150lbs .... but also has water in it while under way ... FO removed his and thinks it the greatest thing since "Sliced Bread" ....but dont pay much attention to him......

its EZ to remove .... you could try it ... I like the traditional look with it on ...

Treads

I would agree with offthefront, estimate between 125-150 lbs. Some variation can be expected due to glass thickness. The underside of the chamber on my 91 292 baries between 1/8" and almost 1/4", port to starboard respectively. I found this out as a result of a modification I did to relieve exhaust backpressure. Simply cut 3-1/4" holes on the underside (not visible unless your under the platform) of the platform, approximately 2" back from the transom. The sound did increase slightly more to my liking than the wife's, as well as allowed better drainage of water when running, thus reducing weight.

Just my 0.02

RedDog382

Mike,

I think he has the new style boat with the moulded in platform. The silent thunder just attaches underneath and you really don't see it like the older design.

t500hps

I have a 99 312 and the Silent Thunder box is completely different than the older SR-1 models you guys are refering to. I took mine off by myself this winter. 4 bolts and a little muscle and it was off. It weighed more like 60-70 lbs and although it carries some water while underway....it's not much. I like it much better without. I can hear the engines a little better and some of the rattles Formulas are know for come from that damn box.

offthefront

iTrader: (1)

Yup my bad ....soooo I'd loose that puppy in a heartbeat ...But haven't I heard where its the Ladder rattling on the new platforms? Still ....drop that box ...

formuladude312

I agree with t500hp its no more then 70-80 lbs tops, I removed mine and went with ggb transom mount mufflers, So much better then with it on, It could probably get up to 125lbs when it is filled with water, Really no speed gain but better apperance and sound with the ggb's, 4 bolts and a 2x4 in one of the exhaust holes with a up and down pry and its off, It fits snug up under the swim platform.

Grog

Thanks for the input guys. 80# is substantial enough to consider removing it.

Is there any cosmetic (gelcoat) work that needs to be done that shows when the box is removed?

formuladude312

Just a good degreasing and waxing from the soot that will be behind there.

t500hps

After cleaning up (It's nasty in there) I had 1 small area where the box was rubbing under the swim platform. Left an area 1/2 by 1 1/2 inches that the gelcoat was rubbed down a little but unless you stuck your head under the boat and over the drives you really couldn't see it. When I had some bottom work done a few months later I had them fix that little spot since they had the boat anyway.

If you down like the boat without the box you can always put it back on......but I bet you'll never consider that once it's off!!!