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What exhaust for 311?

Old 04-17-2005 | 06:46 PM
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Default What exhaust for 311?

New 540's are being built. What exuast should I get? I know I need the extra 3" rise to hit the transom holes and dont want to fight with them to line up. Also looking to avoid the big bucks like having CMI custom build a set. What are you guys running on your 311s? Thanks.
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Old 04-17-2005 | 07:22 PM
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Default Re: What exhaust for 311?

ask Formula Outlaw ..... he's got a nice setup .. I just installed some Gil Mainifolds with SM pipes ....I had to have wedges made to hit the holes ...and he had to have some wdges made also ....
Attached Thumbnails What exhaust for 311?-resize-resize-dsc00029.jpg  

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Old 04-17-2005 | 11:11 PM
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Default Re: What exhaust for 311?

I went with EMI Thunder aluminum exhaust and Stainless Marine tips with the internal "SuperFlapper". I had to have a 3 inch spacer made up of aluminum billet that cost me seven hunded bucks so the risers would line up with the holes in the transom. The SS risers have the three inch spacer built in. I went with the aluminum because of the weight savings. If you're running a hot cam, be sure to plumb it so the water enters the pipe as far down as possible. With your setup, I'd go SS.

Too Old at Trick Marine can hook you up with about anything you might want. He's the best....

I couldn't be happier with the results. Here's a couple of pix.
Attached Thumbnails What exhaust for 311?-boatrunnning-009-small-.jpg   What exhaust for 311?-boatrunnning-010-small-.jpg   What exhaust for 311?-boatrunnning-006-small-.jpg  


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Old 04-17-2005 | 11:43 PM
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Default Re: What exhaust for 311?

Originally Posted by DustinM
I know I need the extra 3" rise to hit the transom holes and dont want to fight with them to line up.

Dustin,

I understand why you would assume this. However, the conclusion is incorrect. I went through this several years ago when upgrading the exhaust on my 311. 3" rise C.M.I. WILL NOT work ... they will not clear the fiberglass rim around the engine hatch area without extensive cutting into structural fiberglass (I had to return the 3" rise I ordered). I used the standard C.M.I.'s, but the angle on the tailpipes was almost horizontal and I had a lot of problems with reversion.

To solve this, I had to trade up to a 382!

The 311 and silent thunder does present a problem and I'm still not sure what the best solution is. I had previously ran Gils and had no reversion problems, but they were very tight and everything was a b**** to get to. I also believe Gil is now out of business anyways. You might want to call Bob at Lake Precision Welding in Cleveland ... he did all the welding for Gil and now does Hardin's welding. He made new tailpipes for my 382 that are dry to past the transom so no problems with reversion.
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Old 04-18-2005 | 05:16 AM
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Default Re: What exhaust for 311?

Are your 540's short deck strokers or are they tall decks? Don't forget to allow for increased height and width if they are tall deck blocks.
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Old 04-18-2005 | 07:27 AM
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Default Re: What exhaust for 311?

Give Fred (Too Old) a call. We went through "Exhaust systems 101 for a 311 Formula together". He can set you up. Just tell him what you're doing and he'll take it from there. Best prices anywhere and he has set customer service to a new level. Trust me on this oen. You won't be disappointed.

On the EMI Thunder series, the SS riser which has that three inch spacer included, will line up just about dead perfect with the stock holes in the transom. Fred has access to just about any exhaust system you can think of, but most importantly he'll steer you in the right decision depending on YOUR set up. Call him.

As you know he's an OSO advertiser. "Trick Marine"...Good luck and keep us posted.
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Old 04-18-2005 | 08:28 AM
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Default Re: What exhaust for 311?

Originally Posted by Formula Outlaw
I went with EMI Thunder aluminum exhaust and Stainless Marine tips with the internal "SuperFlapper". I had to have a 3 inch spacer made up of aluminum billet that cost me seven hunded bucks so the risers would line up with the holes in the transom. The SS risers have the three inch spacer built in. I went with the aluminum because of the weight savings. If you're running a hot cam, be sure to plumb it so the water enters the pipe as far down as possible. With your setup, I'd go SS.

Too Old at Trick Marine can hook you up with about anything you might want. He's the best....

I couldn't be happier with the results. Here's a couple of pix.

http://www.eddiemarine.com/Cart/deta...CategoryID=107

F/O - does this set up negate the need for the custom 3" spacer??
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Old 04-18-2005 | 07:15 PM
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Default Re: What exhaust for 311?

Originally Posted by CMG
http://www.eddiemarine.com/Cart/deta...CategoryID=107

F/O - does this set up negate the need for the custom 3" spacer??

Yes. If you choose the SS risers, the three inch spacer is "built in".

In the older Eddie Marine catelogs, they used to sell a 3 inch spacer for their aluminum risers, but is now a discontinued item. Different reasons were given for the discontuation, I personally think it was intefering with the sales of their SS units. Just my two cents though.

Like I said, I was as interested in reducing weight over the props as anything. We all know how azz heavy our boats are anyway. Between losing the silent thunder box and swapping over from those Mercruiser "anchor" exhaust units, I lost over 500 lbs. My boat now sits close to two inches higher out of the water at the stern. That's like losing two inches on my "X" demension". It certainly made a difference in the way my boat runs. Doesn't "jump" up on plane quite as quickly as it did, but once up there, it accelerates stronger and I gained a solid 4 mph on the top end. (GPS)

Plus it sounds better and I personally like the looks of a clean transom.
Attached Thumbnails What exhaust for 311?-marvistarun-004-small-.jpg  

Last edited by Formula Outlaw; 04-18-2005 at 07:23 PM.
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Old 04-18-2005 | 07:53 PM
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Default Re: What exhaust for 311?

Originally Posted by Formula Outlaw
That's like losing two inches on my "X" demension".
Well.......... not quite Outlaw. The "X" dimension is a measurement of the drives to the bottom of the hull. All you did is raise the whole hull out of the water. This does not change the "X". You may be dragging less hull but, you're not dragging less drive. Drive depth relative to the bottom of the boat is unchanged.
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Old 04-18-2005 | 08:10 PM
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Default Re: What exhaust for 311?

Thanks guys! I will call Trickmarine tomorrow.
RedDog, I have short deck blocks and will be on the edge of reversion. Hopefully I can find something that will bolt right in. -Dustin
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