I cant draw for dog dew but work with me here.

use a tpi baseplate as the well, baseplate. but make a plenum that bolts right to the baseplate. no runners, it just comes all the way around and goes right onto the tpi baseplate. that way the runners are still at an agle thats good for performance, but you cut the runner length in half, providing much more high rpm power, IMO it would flow near HSR.

Has anyone thought of this?

 

thats kind of the philosphy of the super-ram, except they use a short runner to bring the plenum horizontal. It would be tough to make a plenum to bolt directly to the baseplate.

besides the obvious fabrication difficulty, the baseplate itself is somewhat of a restriction, so you are better off using something that has larger ports to begin with. Since the runners run horizontal, they tend to have a poorer entry angle into the head runner, and have a less than optimal runner cross-section.

don't get me wrong, it would be neat, and different, but its alot of work for possible minimal gain.

everytime I think about it, I always come back to the realisation that the baseplate becomes a bottleneck.

 

Try it!

Might be a good idea to go with an aftermarket base

 

How about no plenum at all, just some TWM style throttle bodies all around. Tune it Alpha-N (TPS & RPM). Would look pretty slick. Alpha-N isn't very adaptable to climate change though (IMO not daily driver material). It would give the runners some length, compared to TB's stuck directly to the heads, or plenum stuck right on the base.

 

Don't assume that if you shorten the runners by half, that the rpm for resonance will double. That only works in a length-mode acoustic resonator, and TPI (or Superram for that matter) isn't that kind of resonator.

The resonance(s) are determined by the combined acoustics of the runner AND the plenum they're attached to. It's complicated, too much so for TGO.

Also consider -- if you shorten the runner enough (eliminate the curved runners and then drop the plenum atop the base) then the L98/LB9 TPI intake manifold begins to look like the LT1 intake manifold (short runner, similar-sized plenum).

The reason why the LT1 version breathes better is that the runners are approx 2" by 1" (2 sq inches), while the TPI is 1.4" diam (1.54 sq inches). If you accept that a 350 runs out of good airflow near 4500 rpm because the Mach Index is too large (say above 0.5) for the TPI, then the LT1 will run to 5900 rpm (for the same Mach Index) because it has 30% more flow cross section. The deficiency is that you no longer get acoustic cylinder filling near 3000 rpm like you do on the TPI... but that's the price to pay for more power at higher rpm, and the better flowing LT1/L31 heads more than make up the torque loss near 3000 rpm. HTH.

 

Reeeallllly.....

 

Really. Especially for you.

 

yeah i took a look at all he was saying. and th vocabulary words took me a while to look up on webster. But i think imay have his idea.

He is just saying that if we shorten the runners power will be lost at low rpms, but gained in the uppers. Becuase velocity is lost.

 

Old joke CR. Kdrolt caught it I think though.