getting motor together finally going to put splitters in the center exhaust port. has anyone used speed way or made you own? thanks billy
Before you jump, are you planning a BIG cam with a lot of overlap? And planning on running the engine in "Race Mode"? If neither of the above, forget the port dividers-the negative of introducing an obstruction in an already restricted port far offsets any slight advantage at top R.P.M.
That is what I've always heard. More detrimental than beneficial for a street engine. No body can see them so lie about it if you want to.
I don't think they are really necessary for a street engine that turns about 2600 rpm at cruise. But, I say that in hind sight because I put them in the 8BA that I am currently running. If you have the splitters from Speedway, I think you will find that they do not mount like you think they do. It is implied that they are held in place by a head stud. When I tried it that way, they sat very low in the chamber and would have greatly restricted the exhaust flow. But, if you do some grinding on them to get them to fit further up directly between the valve bowls they give a nice "coke bottle" shape for each side. Mind you, there is a lot of "zen" that goes into this because you have to use your fingers to feel how much to grind and where when fitting them. Finally, how do you attach them? The way I did it will make some cringe, no doubt. I drilled a hole into the center chamber via the water jacket into the splitter. I tapped the splitter, put JB weld on the shoulder of a stainless button head to seal it and stuck it in there. My thinking is that coolant should keep the head of the screw cool enough that the JB weld won't be burned off. Been driving that engine now about 3 years. Another thing you might consider. One of the aesthetics of a flathead is its sound. I run lake headers with muffler inserts so it is a little louder than most. One of these days I hope to park next to another little louder flathead without splitters to see if there is a difference.
Joe Abbin, a master flathead builder also says in his last book that they do no good. I bought a nice set of them, they are on the shelf in the closet.
As far as something to do with the center exhaust passages, do you guys in the know think that there is any merit to some sort of ceramic coating in there? I believe there is some merit to the theory that 2 cylinders dumping heat into one internal passage may be a source for heating woes in a Ford flathead. Maybe that is something Hellmet should explore instead of splitters.
Never heard anything positive about splitters and never could understand why anyone would want to put more restriction in something that was born with breathing problems. To me it's like a guy with lung cancer getting autoerotic asphyxiation.
Ghost, if you get them far enough up in the chamber I cannot see how they would be restrictive and they would do their theoretical job of not having back pressure on the siamesed cylinder at high rpm. As I was feeling around in the center bowl after installing mine it felt to me like it had a coke bottle type of venturi shape which I have always heard is a good thing for gas extraction. (I'm studying your avatar as I write about feeling about in the center bowl. From another one with a hot avatar.)
Tbird I guess it's just a matter of opinion maybe on the splitters.......... However that avatar of yours is pretty damn smokin! I didn't notice her before prob cuz I hadn't had coffee yet lol PS I just got back from San Antonio a couple of weeks ago I love that freakin place! Mexican chics are soooo Fing hot!
we ran them at Bonneville and one fell out. Our buddies who had them on their race car had one come loose and block the exhaust port. Not good! I don't run them anymore.
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