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jdbillin 11-07-2014 02:55 PM
SB Exhaust manifolds
 
Does anyone have any idea what these are?

They came off of a 350 out of a boat that all the guy knows.

http://i1382.photobucket.com/albums/...ps48e0a1a1.jpg

Trying to figure out if their worth buying and trying to find another set, I'm not even sure if they will work in my boat or not

Thanks

dereknkathy 11-07-2014 05:10 PM
some old jet boat something. 40 year old aluminum. no design work went into them. they are just a straight line minimal size exhaust that you need to fab elbows to run them. worth about 85 cents a pound these days...

jdbillin 11-08-2014 12:13 PM
Damn ok, figured they would of been a whole hell of lot better than the stock cast ones I have now, Good thing I asked first

Thanks

BUP 11-08-2014 12:21 PM
depending on ur app, set up and waterline that exhaust could be very well prone to water reversion. so just call them engine killers for now.

Looks like an old jet boat or old ski boat inboard with a direct drive app those were used on.

the deep 11-08-2014 01:02 PM
See the difference . These were on my 383 .

http://i1243.photobucket.com/albums/...p/100_0342.jpg

jdbillin 11-13-2014 02:27 PM
Originally Posted by BUP (Post 4216070)
depending on ur app, set up and waterline that exhaust could be very well prone to water reversion. so just call them engine killers for now.

Looks like an old jet boat or old ski boat inboard with a direct drive app those were used on.
Gotcha, they would be going in a formula 242 I figured they would need modified to get them to fit but if its not worth it I won't even mess with them. I don't even know where I would find another set at

Should I tell him they really are only good for scrap? I would think to the right person they would be worth something

Originally Posted by the deep (Post 4216082)
See the difference . These were on my 383 .

http://i1243.photobucket.com/albums/...p/100_0342.jpg
Theres a huge difference there, Them would also look a whole lot better lol

f_inscreenname 11-13-2014 03:11 PM
Not sure what kind of boat you have but they work well for my boat.

http://www.supernova19.com/resurrect...e/1e2a93f0.jpg

tommymonza 11-13-2014 03:28 PM
You been a little quiet Fckinscreenname. Any new projects coming up or are you just sitting back for a while and enjoying the fruits of all your past efforts.?

SB 11-13-2014 03:57 PM
Originally Posted by jdbillin (Post 4215746)
Does anyone have any idea what these are?
Wasted garage space.

dereknkathy 11-14-2014 05:13 AM
Originally Posted by jdbillin (Post 4218728)

Should I tell him they really are only good for scrap? I would think to the right person they would be worth something.
he is trying to sell them. don't tell him anything. he will either be insulted, or think you are stupid or think you want them cheaper. if he is a friend you need to be diplomatic about why you don't want them. a matching set to replace with later or for the other engine if twins is a good excuse.

DjMikeyC 11-14-2014 09:32 AM
Originally Posted by the deep (Post 4216082)
See the difference . These were on my 383 .

http://i1243.photobucket.com/albums/...p/100_0342.jpg
OMG those are beautiful!!! Are those CMI's? I'm looking for a set to put on my 24 Pantera with a sbc...

the deep 11-14-2014 04:10 PM
Originally Posted by DjMikeyC (Post 4219063)
OMG those are beautiful!!! Are those CMI's? I'm looking for a set to put on my 24 Pantera with a sbc...
Yes , CMI Elbow Tops and dry to the tip tails . Made many little kids cry upon fireup at the dock . Sounded and looked awesome !

SB 11-14-2014 04:37 PM
Hate to post this again, because I've posted it alot (don't want to sound like a broken record) and easily found but here it goes.

Here's a certain marine 502 that I ran it's specs thru Pipemax.
Hint: Look closely and you'll see that KE's header/manifold is literally at the correct dimensions for primary ID and length. Collector of course depends on how long the tails are in the boat.

Quote myself:
Here's one I ran on a certain 502.

BTW: The program givea much, much more info than I have posted below. But it will give you a good idea on things.

Remember, the 'collector' is not just the headers collector. If risers and tails are same ID, which most re, then they too are part of the collector.


Pipemax
Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness


502.176 CID from 3800 to 6300 RPM
--- Single Primary Pipe Specs --- Diameter= 1.899 to 2.024 Length= 33.7 to 36.7 inches long
--- 2-Step Primary Pipe Specs ---
1st Dia. inches= 1.899 Length= 16.9 to 18.4
2nd Dia. inches= 2.024 Length= 16.9 to 18.4
--- 3-Step Primary Pipe Specs ---
1st Dia. inches= 1.899 Length= 16.9 to 18.4
2nd Dia. inches= 2.024 Length= 8.4 to 9.2
3rd Dia. inches= 2.149 Length= 8.4 to 9.2

--- Header Collector Specs (Conventional Straight Tube) ---
Diameter= 3.466 to 3.716 Tuned Lengths= 19.4 best and also 9.7 or 38.8

--- Header Collector Specs (Megaphone or Diffuser Cone Shape) ---
Diameter= 2.966 taper to 3.966 Megaphone/Diffuser Length= 19.4 inches

Best HP/TQ Tuned Collector Lengths= 19.4 , 38.8 , 77.6 , 155.2 inches long
Worst HP/TQ Loss Collector Lengths= 29.1 , 58.2 , 116.4 , 232.8 inches long

Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness
---- Primary Pipe's Harmonics ----
1st Harmonic = 149.4 inches long ... typically never used
2nd Harmonic = 56.5 inches long ... longest recommended
3rd Harmonic = 33.7 inches long ... highly recommended , best Torque Curve
4th Harmonic = 23.4 inches long ... shortest recommended
5th Harmonic = 17.5 inches long ... typically never used
6th Harmonic = 13.8 inches long ... typically never used
7th Harmonic = 11.1 inches long ... typically never used
8th Harmonic = 9.2 inches long ... typically never used

---- Collector's Harmonics (includes Intermediate, Muffler , TailPipe) ----
1st Harmonic = 155.2 inches long ... longest with Mufflers and TailPipes
Note: Worst = 116.4 inches long for HP/TQ Loss
2nd Harmonic = 77.6 inches long ... longest recommended with Mufflers
Note: Worst = 58.2 inches long for HP/TQ Loss
3rd Harmonic = 38.8 inches long ... more bottom-end Torque
Note: Worst = 29.1 inches long for HP/TQ Loss
4th Harmonic = 19.4 inches long ... highly recommended , best Torque Curve
5th Harmonic = 9.7 inches long ... reduced Torque , more top-end HP sometimes
6th Harmonic = 4.9 inches long ... reduced Torque , not recommended

f_inscreenname 11-15-2014 01:24 AM
Originally Posted by tommymonza (Post 4218753)
You been a little quiet Fckinscreenname. Any new projects coming up or are you just sitting back for a while and enjoying the fruits of all your past efforts.?
With all the hold ups I just finished up the 18 Donzi Classic exhaust yesterday. Being it's 32 degrees as I type this there wont be any test drives until spring and if I cant sell it I cant do another. I also may take a brake from restoring boats for a while. The economy can be anything they want to believe but even in Maryland the classic boat market is a loosing adventure at this point and time. Never really expected to make a lot if any money but at the same time I cant afford to lose a whole lot either.
As a real project I'm starting to really think hard about getting real motors together for the 24 race boat and taking it out for real (poker/show) runs a couple times a year.
https://www.youtube.com/watch?v=iWiQ...=TLq9MTcvX0kZI

buck35 11-15-2014 06:15 AM
^^^^^ nice work!

ICDEDPPL 11-15-2014 09:34 AM
You could see what these go for

:

http://www.ebay.com/itm/261662896965...S:1120&vxp=mtr

mike tkach 11-15-2014 09:48 AM
Originally Posted by ICDEDPPL (Post 4219542)
those are some nice looking manifolds.GREAT for making back pressure!

jdbillin 11-15-2014 02:56 PM
Originally Posted by dereknkathy (Post 4218967)
he is trying to sell them. don't tell him anything. he will either be insulted, or think you are stupid or think you want them cheaper. if he is a friend you need to be diplomatic about why you don't want them. a matching set to replace with later or for the other engine if twins is a good excuse.
Unless I figure out what there worth their probably just going to get scrapped he has no use for them and there just sitting there , I told him I might be interested if I can figure out if they'll work for me and if I can find another set. I told him that I would do some research and see what I find, he's not to worried either way
Originally Posted by ICDEDPPL (Post 4219542)
Thanks for the link ill keep an eye on them

f_inscreenname 11-15-2014 06:37 PM
Originally Posted by buck35 (Post 4219469)
^^^^^ nice work!
Thanks

dereknkathy 11-18-2014 05:42 AM
alum GLM's are the best all around bet for small blocks. handle up to 350 or so hp. a LOT lighter than iron. hold up well. cost about 1k per set.

phughes69 11-19-2014 06:34 PM
jdbillin, what manifolds do you have now?

jdbillin 11-20-2014 04:35 PM
Right now I just have the stock mercruiser cast iron ones. I only currently have one set though


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