tunnel ram
- Thread starter lyonsy
- Start date
There are several versions of a modified efi manifold that would be considered to be tunnel ram. One set up uses only the lowered sectionand a nother that uses both halves.
There was one listed for sale here.
http://fordsix.com/forum/viewtopic.php?t=35829
fordman 75 selling, could be 1 x 4v or 2 x 2v downdrafts or 2 x 2v side drafts.
In a fab from scratch for the runners to be long enough would have to be curved "J" or "U" shape to a plenum. A straight runner length would be limited by shock tower / fenderwell.
There was one listed for sale here.
http://fordsix.com/forum/viewtopic.php?t=35829
fordman 75 selling, could be 1 x 4v or 2 x 2v downdrafts or 2 x 2v side drafts.
In a fab from scratch for the runners to be long enough would have to be curved "J" or "U" shape to a plenum. A straight runner length would be limited by shock tower / fenderwell.
hey
the thing i have troble working around is on the v8's all runners are equall in length to a common point.
the also have very little if any plenium chamber.
they also dont have any bends in them as well.
so to me http://fordsix.com/forum/viewtopic.php?t=35829 is just a plenium chamber type manifold.
so to do one the two outer cylinders whould come out a a J from the port at say a 45deg up angle to the carby base.
the next two whould come out under the outer manifold the a J upto the base.
and the the two inner ones whould come out under both them and probly be in a U after droping a little to pass the other runners.
for a down drought?
for a side draft whould be a bit esyer as you could just have the inner ones rise up aboe the carby to get the extra length while running the outer as straght as possible.?
drift
the thing i have troble working around is on the v8's all runners are equall in length to a common point.
the also have very little if any plenium chamber.
they also dont have any bends in them as well.
so to me http://fordsix.com/forum/viewtopic.php?t=35829 is just a plenium chamber type manifold.
so to do one the two outer cylinders whould come out a a J from the port at say a 45deg up angle to the carby base.
the next two whould come out under the outer manifold the a J upto the base.
and the the two inner ones whould come out under both them and probly be in a U after droping a little to pass the other runners.
for a down drought?
for a side draft whould be a bit esyer as you could just have the inner ones rise up aboe the carby to get the extra length while running the outer as straght as possible.?
drift
Seems to be some confusion between tunnel ram and individual runners manifolds.
TR have large plenum. IR have no or minimum plenum. Runners for either TR or IR are usually equal length, straight and as direct as possible.
For pictures of tunnel ram manifold see: Summit Racing p# DRT-41134000, TFS-54494140 or WND-1984. All have large plenums.
For inline engines there are space limitations that dictate runner shape especially when trying to use a specific length of runners and maintain a certain hood line...
Most efi manifolds, the Ford 300 included, are TR in design. The ram in tunnel ram refers to the ramming or compressive effect of the resonance wave in the intake runner at a particular RPM. The longer the runner the LOWER the rpm where the ram effect occurs. The design is not just for equal flow to all cylinders but for equal flow AND ram effect to all cylinders at a specific rpm.
As far as grouping intake runners the 300 can be treated as two 3 cylinder engines The firing orders is such that 1-2-3 can be connected to one plenum and 4-5-6 to a second with balance tube connecting.
Any TR manifold built for the 300 will be very similar in design and appearance to the efi manifold. Two big 2V sidedraft on the side of the plenum would be optimum for flow with each in front of 3 cylinders.
TR have large plenum. IR have no or minimum plenum. Runners for either TR or IR are usually equal length, straight and as direct as possible.
For pictures of tunnel ram manifold see: Summit Racing p# DRT-41134000, TFS-54494140 or WND-1984. All have large plenums.
For inline engines there are space limitations that dictate runner shape especially when trying to use a specific length of runners and maintain a certain hood line...
Most efi manifolds, the Ford 300 included, are TR in design. The ram in tunnel ram refers to the ramming or compressive effect of the resonance wave in the intake runner at a particular RPM. The longer the runner the LOWER the rpm where the ram effect occurs. The design is not just for equal flow to all cylinders but for equal flow AND ram effect to all cylinders at a specific rpm.
As far as grouping intake runners the 300 can be treated as two 3 cylinder engines The firing orders is such that 1-2-3 can be connected to one plenum and 4-5-6 to a second with balance tube connecting.
Any TR manifold built for the 300 will be very similar in design and appearance to the efi manifold. Two big 2V sidedraft on the side of the plenum would be optimum for flow with each in front of 3 cylinders.
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