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inbetween
01-07-2009, 11:42 PM
Has anyone put Gil manifolds and dry tail pipes on a big block bravo 311, 292, 272?

I have a chance to purchase some used stuff and wondering if the dry tails fit/line up with the factory exhaust holes in the transom or what I'd need to do to make them work.

Thanks,
Adam

RedDog382
01-08-2009, 02:01 AM
I had Gil exhaust on my '89 311 for a while before switching to CMI headers. The stock tails will NOT fit as the holes for Silent Thunder are located higher than standad Bravo cutouts. I had some custom tail sections and needed to use wedges to get exactly the right angle to match the holes. You must also be VERY CAREFUL to not set yourself up for water reversion.

My Gils were sold to someone with a Fountain, then to another 311 owner I know who has since sold the boat. I will have to check and see if I can find out where they are currently.

I have connections in Mentor that may be able to hook you up with a local welder who can do the job on tails for you.

inbetween
01-09-2009, 12:00 AM
I had Gil exhaust on my '89 311 for a while before switching to CMI headers. The stock tails will NOT fit as the holes for Silent Thunder are located higher than standad Bravo cutouts. I had some custom tail sections and needed to use wedges to get exactly the right angle to match the holes. You must also be VERY CAREFUL to not set yourself up for water reversion.

You are Chris, right? I'm friends with Jeff and Marilyn from Mentor. We met briefly in St Clair a couple of years ago.

Thanks for the reply. You're talking reversion, is that an issue using dry pipes? As far as the exhaust cut out in the transom, can I relocate them to match the Gil tail pipes or will that be too low? Where did you get the wedges? Have them made or are they available from corsa/gil?

RedDog382
01-09-2009, 02:08 PM
Yep, that's me. Just talked to Jeff the other day. Do you have the silent thunder platform on? Reversion would not be a problem if you went full dry, but I was always worried about running dry exhaust the Silent Thunder it because of the heat. I was able to get the wedges through Gil at the time. They had several standard height wedges. The ones I used were maybe 1/4 or 3/8 inches at the front and tapered at the aft end, but these were custom tails too, not the standard. A good fiberglass person could fill and reset the through-hull openings, but it won't work if you still have Silent Thunder.

inbetween
01-09-2009, 09:33 PM
No more Silent Thunder. I was thinking the exhaust openings may be too low with the way the boat sits in the water. I was also thinking reversion may not be a big issue going dry, but if the exhaust is low, may be some water coming in when sitting?

offthefront
04-06-2009, 05:55 AM
I'm using Gil manifolds and Stainless Marine pipes for TRS Drives and the pipes are about 3/4" shy of going all the way thru the stock Silent Thunder holes in the transom ....I did have to wedge the pipes about 1 1/8" ....My pipes are wet but all the water exits at the end of the pipes ... I will post some pics .....m

ROGUE
04-06-2009, 12:28 PM
I had to use wedges on mine. Be sure your engines are aligned perfectly before sizing them, (I had to do this twice)

FULL FORCE
05-28-2009, 10:49 PM
Adam... get that exhaust on?? you boatin yet? call me....

inbetween
05-30-2009, 05:37 PM
didn't get it on yet - low fund$ blues

offthefront
08-14-2009, 06:49 AM
Gil manifolds ....Stainless Marine pipes for TRS on Bravo Setup ...the blue hose you see are about 8" long ...the pipes lack about 3/4" of passing all the way thru the transom ...so we used the blue hose with rubber Flappers glued on the ends ....notice the wedges ....I like the way the water exits the stainless marine pipes .....m


http://www.youtube.com/watch?v=h8B07Q9qXBM