Crusader manifolds

"Nothing obvious from the pict

"Nothing obvious from the pictures. The elbow will "end" forward from where it currently does. that means a hose stretcher or new hose. You can estimate the migration forward by using the carb; the installation manual has detailed drawings in the back.

You could always make a new hole on each side and have twin dual exhausts.

I can't say I've ever seen a merc elbow with that hard 90 deg bend; most go straight back or with a modest (0-15 deg) downward tilt. If that's still the case, you need about 18" of straight hose before making any bends....I seem to remember if you come inside of 12", you need cast iron or stainless tube to redirect any exhaust.

Two advantages; only one may be relevent now. The first is all that iron gives you pretty good performance life which has been consumed. The other potential benefit is that all that cast iron makes for superb ballast (but only if needed.)"

"Greg,
I hadn't thought a

"Greg,
I hadn't thought about the width.
The tanks may be an issue. Are the center riser type manifolds that much wider than the old logs?
As you can see from the photos, these old unit are massive. I guess I assumed I would have better clearance??

I will get some measurements from the stringer to the fuel tank and see what I have.

Is there any place to get dimensional drawings of these aftermarket manifolds?

According to Crusader, the new small block GM (305 and 350) are 28.1 inches wide at he manifold (the widest part). The Crusader manifolds are 4" wide each, adding 8" to the width of the engine (plus a little for the valve cover clearance.

Bob"

"Bob,
I am not sure how much

"Bob,
I am not sure how much wider we are talking about honestly since I never considered switching from the OEM parts. I will check on engine specs of Crusader vs. Mercruiser. Mark may know. If your enigines are still in your garage as pictured you could measure them as they are to see the width you are working with. The newer Crusader 305 engine may be close enough for comparison."

"Greg,
The engines are back,

"Greg,
The engines are back, but they are now only long blocks, not much on them now.

Mark,
I do like your idea if duel exhaust (I did that on my old Donzi) but the Carver has an underwater exhaust that I would like to keep.


I think if I come straight out (12" like you said) and then use a 45 deg. SS pipe, then back into the fiberglass exhaust, it may work.

Bob"

"Some measurements:
Boat:
[b

"Some measurements:
Boat:

Engine C/L to fuel tank is 18"
Engine C/L to Engine C/L is 40.5"
Front engine mount to bottom of deck is 29.5"


Crusader Manual:

Engine C/L to outside edge of the manifold is 14"
(not much room).
Engine mount to top of standard manifold is 23"
Engine mount to top of 4" exstended manifold is 27 3/4"

Soooo, if the "merc" stuff is similar to the newer Crusader, it will fit (tight) but the 4" is all I can use, the 6" might be too high."

"Rebuilt engines don't hel

"Rebuilt engines don't help much at this point

http://i29.tinypic.com/34hdmxh.jpg"[/IMG]"

"Bob:

With those underwater

"Bob:

With those underwater exhausts, if the transom "thru hull" is shielded (water can't get back in if you back up) the vertical drop isn't as critical....Its like a DWV horizontal run, you just need enough slope to encourage the water to roll out.

I'd be inclined to call crusader tech support and ask them how much riser is needed."

Bob:

found a MIE 5.7L drawi

Bob:

found a MIE 5.7L drawing - look in your inbox per your profile. Too big to post.

"Bob,
Let us know what you fi

"Bob,
Let us know what you find out with Mark's info and your comparison."

"Mark,
Got your email and the

"Mark,
Got your email and the drawing, thanks.
There is an idle port in the exhaust, just above the water line, they have flappers on them, but that would be my only concern. They end up about
10" below the standard riser.

Greg, you are right, the Merc is about .90 inches wider than the "new" style Crusader.
That's only 1/2" on each side, so I think I'm OK.

I don't know how wide the old logs are.
When I get some time, I will go dig one out and see if I can figure it out.

Anyway, I think this leaves me about 3.5 " room on the outboard side next to the fuel tanks.
Not a lot of room, but I should be able to get my arm in there to change plugs.


Thanks
Bob"

Cool. Good luck. Post a few

Cool. Good luck. Post a few pics of the finished project if you get a chance.

"Bob:

You have PLENTY of ro

"Bob:

You have PLENTY of room....some of that merc stuff stated you could install small blocks with a 33" spacing, crank-to-crank. I've seen pictures of those engine boxes and read stories of the $1000 tune-up (due to the labor required to R&R the engines)."

"Sure will, not a problem.
It

"Sure will, not a problem.
It will be next march or so, before I can build the engines and get them installed.
I am having back surgery in two weeks, and will be out of action for 4 or 5 months. Hope to order the parts next month.

This will drive me nuts "

Good luck with the neuro-fixer

Good luck with the neuro-fixer; most of them work magic nowadays!