I have some questions related to the Offenhauser Turbo Thrust tunnel ram, the plenum, and the Offy Individual Runner adapters.
The offy documentation is very specific that you should not modify the plenum, and I understand why they would put that in print, but the center divider just does not look like it is the "hot" set up, and in comparison to newer technology, just does not look quite right.
My opinion is based on what I have see being sold these days, and that all the sheet metal tunnel rams have open plenums.
The engine has closed chamber iron heads, stock stroke, .030 over, 10:5-1 compression, and the cam is a Comp Cams grind number 300-1/310-1 s106 with an Edelbrock Torker on it. The engine is in a 95 Mustang GT with a top loader and 3.73 gears.
I am thinking of swapping to the T/R set up and would like some first hand input.
What I am very interested in knowing is, does anyone have any experience using the Offy 6040 I-R adapters that replace the plenum all together, and what were your impressions and result?
Thanks much, Mike H.
i haven't run them yet, they've been on the wish list for 25+ years and just obtained a set fairly recently
they're 2" tall overall and the divider begins right at 1.4" down from the top, it's just there to break the flow over the gasket flange.
the carb pads are sideways mount. with a plenum in each adapter the carbs can be 1:1, progressive or even vac sec. at part throttle the engine should run pretty OK pulling from across the plenum like any single carb on an open intake, but as the blades all equalize i can see the carbs being tunable bbl/cylinder
interesting, on the 'bay right now there's a single top that PN's for 289/302 with a divided plenum and also a 'special' single top with an open chamber that PN's for 289/302, Boss 302 and 351C... but all the std single tops are specific to each engine, now i wonder which single top i have?
there'll be phantoms, there'll be fires on the road... and the white man dancing