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Quote:

Originally Posted by vintage chromoly (Post 4389278)

Is that a "jet" so to speak brazed to a small tube?

It`s a gas orifice from a furnace.. brass, so easy to customize
and i happen to have an unlimited supply:daz:

I like the GEN IIIs because no more leaks but I don`t think they are as good as a tuned header .. it`s basically a big fire hose, they claim no power loss .. I`m not so sure.

Quote:

Originally Posted by ICDEDPPL (Post 4389257)

I`ve found it depends on how long the tail is .. My STEROID headers the collector was so far back there was a short tail and it reverted. The collector would be soaking wet... worse with mufflers closed. Had to buy a bunch new valves this year due to pitting from reversion. The current SM Gen 3 have a long tail and no issues whatsoever.

I do dump overboard from inside the boat but have a hole inside the tail at the end to keep the mufflers from burning up.

http://33outlaw.zenfolio.com/img/s6/...84605872-3.jpg

Looks like a jet for after burner! Lol
Looks good did the tail pipes come welded at the end?

Quote:

Originally Posted by MILD THUNDER (Post 4389089)

Maybe if full force tim dynos his afr headed 540s, he can try it with his stainless marine manifolds, and then a set of CMIs.

.

Let's hope we can find out, I have Stainless Marine and dry to the transom, hope that is helping me over other manifolds....

Quote:

Originally Posted by Full Force (Post 4389530)

Let's hope we can find out, I have Stainless Marine and dry to the transom, hope that is helping me over other manifolds....

Be interesting to see! :coolcowboy:

yep, I need to talk to Ryan and see what I can arrange....

Quote:

Originally Posted by MILD THUNDER (Post 4389531)

Be interesting to see! :coolcowboy:

Just wanted to add some info on the wet vs dry tails. Bobl and Raylar found 20-25 hp gains on a set of CMI's adding the dry tails on 500-600 hp engines. Bobl stated in a later post that low end torque did not suffer as much loss with the wet tails.

https://cimg6.ibsrv.net/gimg/www.off...40c2d4d48b.jpg
Just picked up these IMCO Powerflow + manifolds for the Talon's 572...... Should do better that the CMI's I have on there now...

Just reading through this thread, I understand with a big cam NA engine good exhaust is going to be more important than a (mild) blower set up, but what about 502 mag with the not great for anything wet joint style manifolds they come with... thinking of doing side mount whipples this winter, mild set up, probably only 4 to 6 lbs boost... what I’ve heard is they “might” build some heat under long pulls, but “probably” be ok... want to do this right so really should I be upgrading the exhaust or am I not going to see any difference? Any suggestions on a (relatively) economical upgrade that still flow well on this mild of a set up? I feel as though when I was considering this last year that the Gils might have fitment issues with the sidemounts. Was considering Lightning’s but what mild thunder posted above although that was a while ago, at that rate might as well go with cmi cost wise?

Thanks!
Joe

Quote:

Originally Posted by JD430 (Post 4644694)

Read above. The only good data set shows the thunder n lightning performs the best and costs $2900.

we would assume merc has some data showing you’ll want big tube headers in the 850+hp range. But no one has confirmed this with a header shootout on a big blower motor and shared the data.