IMM Engines 408 build

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OK, on the lift numbers. With that lift, the narrowest sweep you can get is going to be a something like .035" to .040" wide. (I'm being lazy and did not take the time compute the exact number...).

You need to forget the idea of the sweep being centered, unless you want to do a crazy amount of machine work. Don't take the info off of websites that tell you to do so. A roller tip being off center does not change the side force exerted on the valve tip 1 iota; that very small side force is the same whether the roller is centered or not.

The only way to get the sweep centered AND the sweep to its narrowest at the same time is to:
  1. Change the rocker center height to get the 90 degree angle between the rocker-center-to-roller-contact line and the valve axis, at mid lift
  2. Then move the rocker center towards or away from the valves to re-center the sweep... but this require moving the studs which involves a lot of careful, custom machine work and so is not practical in most cases.
 
x2 what nm just said
NO quick and dirty answer
NO easy answer
however if you have a mill it is not hard to drill&tap & install oversize studs offset a little
There are 7/6 tops with half inch bottoms you can offset more
u just barely clean the threads on one side
you can calculate the thread depth and do the math
more than that takes inserts
there are also rockers with a wide range of arm lengths
did I say I do not like small studs with any additional spring pressure over stock?
someone here measured a bunch at one time
 
Well, if you get away from the idea that the sweeps needs to be perfectly centered, then you gain some flexibility, and can more easily get the sweeps narrower. You may have to change pushrods, but very probably no moving of the studs. Your level of valve lift would benefit from making things better IMHO.

Can you measure how wide the sweep is? Your report of 'wide' may not be all that wide after all. And to your original question, no way to tell you to move the rockers up or down without seeing the angle of the rocker to the valve tip at mid lift. (Mike may just know the answer from long experience with those particular parts...)
 
nm9stheham said:
Can you measure how wide the sweep is? Your report of 'wide' may not be all that wide after all. And to your original question, no way to tell you to move the rockers up or down without seeing the angle of the rocker to the valve tip at mid lift. (Mike may just know the answer from long experience with those particular parts...)
Click to expand...

I can... but would have to take the valve cover off..lol
I'll keep the idea in my mind and will get to it in the near future... I might have to remove a valve cover in order to switch out a breather grommet.
 
Sound good but i think you have a belt slipping at idle:lol:
Just kidding sound real good at the back.
 
Had to fab up brackets for the intercooler. This thing just didn't fall in place and hook the piping to it...:mad: Of course I was not expecting it to.
I need to take some pictures with the hood closed... looks pretty awesome..:lol:
There goes the sleeper look I was trying to keep.
If you ever go this route get a Treadstone intercooler. They flow better than the China ones and far as I can tell they are WELL built. I was told beforehand about the Treadstone by others that run boost. It really works good. At idle I can feel the intake side of the intercooler and feel the exhaust side and there is definitely a temperature drop.

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