Don Terrill’s Speed-Talk

Joe Sherman or others who have experience with this t-ram.
Mine was port matched as the paperwork that came with it suggests. Meaning match port to heads up approx. an inch or 1.500 up in the port. In other words practically nothing other than a match.
The "width" of the port could be "widened" better at the TIGHTEST point to provide a better match to the heads........in other words , the port in the manifold gets tight towards the exit ( ABOUT A FEW INCHES or less UP THE PORT ) , then OPENS UP to match the head port entrance. IF I open up the cross section of the tight spot will the engine respond favorably to that?
This is a healthy drag race 377 , 14-1 , good roller etc etc.

It may get tighter width wise but what about height wise?

In general you want the point of the least amount of port area to be one stroke length back up stream from the back side of the Intake valve and the runner should have a expanding taper to that minimum port area starting in the runner entry in the Plenum.

It sounds like in general, that yes you should rework that runner area to releave that pinch point.
If at that pinch point the runner has any curve to it then add port area by grinding on the outside wall of that curve , not the tight inner wall.

mag2555 wrote: ↑Fri Nov 10, 2017 6:58 am It may get tighter width wise but what about height wise?
It sounds like in general, that yes you should rework that runner area to releave that pinch point.
If at that pinch point the runner has any curve to it then add port area by grinding on the outside wall of that curve , not the tight inner wall.

HEIGHT wise..........I guess I could see if the roof can be raised some , there's not much material ( I think ).
As far as your reference to pinch point , the inner walls are fairly straight anyway , so I'm assuming you mean the opposite curved side.

I have tried lots of different things on that manifold. When you make it bigger, it will pick up a very small amount of power on the top end ( 8000 and up ) BUT , it kills the mid range, say at 6000 to 6500 - On our best running 434, all I did was to cartridge roll the entrees and get a good port match.



JOE SHERMAN RACING

OK........
Thanks Joe.........guess I'll leave it alone.

bigjoe1 wrote: ↑Fri Nov 10, 2017 11:00 am I have tried lots of different things on that manifold. When you make it bigger, it will pick up a very small amount of power on the top end ( 8000 and up ) BUT , it kills the mid range, say at 6000 to 6500 - On our best running 434, all I did was to cartridge roll the entrees and get a good port match.



JOE SHERMAN RACING

If your running the engine 8000 and above, you should be running more than 6000-6500 converter. More like 7000+, so, the gain up top would be a positive. That is, if the car is set up right, and you want max et.

Seems like most of the successful modifications to tunnel ram manifolds involve work that is done on the floor of the plenum . . . . . . .

Frankshaft wrote: ↑Fri Nov 10, 2017 8:22 pm If your running the engine 8000 and above, you should be running more than 6000-6500 converter. More like 7000+, so, the gain up top would be a positive. That is, if the car is set up right, and you want max et.

Whats a "converter"?

It's sort of like an automatic clutch for weenies....lol. I guess I'm an bracket racing weenie by my own definition then.