I saw this on inlinefour.com! What benefits would this product have? 6-8 hp? Are they serious? Anyone dynoe'd this product before?

Mike

 

i have yet to see anyone post a dyno plot wid one of these.... it keeps getting asked, but no one has one.

 

B16a B18c Torque only...Don't buy spoons Rubber Chicken you'll just be waisting your $$BLING$$BLING$$

 

LOL thanks man....

Mike

 

the Spoon Ventuli plate really speaks to the issue of the relationship of port size to rod ratio in the various B series engines.

If you follow the Endyn website (which DanPonze doesn't agree with and I realize that this concept is not exclusive to Endyn...hell the domestics have known about this for years but they do go into this in detail for Hondas at Endyn and not here) , then you will know that cylinder filling is affected by the behaviour of the piston on the intake and exhaust strokes of a 4 stroke engine. A long rod ratio (1.65-1.75:1 in an inline 4 banger) has slower piston speeds and more dwell time at TDC. This allows for better flow dynamics and you do not need humungus ports to adequately fill the chamber.

A short rod ratio (<1.65), on the other hand, has fast piston speeds and short dwell time at TDC. This necessitates larger ports to adequately fill in the short time provided by the piston geometry.

So if the ports are too big even out of the factory for the rod ratio, a ventuli plate which makes the ports smaller in cross sectional and longitudinal surface area should broaden the torque curve for that kind of engine. I don't see it making big gains in the higher rpms but it will affect the width of your powerband in the midrange.

It would not be something I would get if you are going with cams that make power from 6000-9000 rpm.

maybe for a street fighter with stock compression and intermediate cams like Crowers 403's , Skunk2's, or Toda A's...

comments / criticisms are welcome...



[Modified by Michael Delaney, 7:13 AM 9/6/2001]

 

so to sum it up, is it worth it to get this mod if you are just getting bolt-ons?

 

actually, to sum it up : if you have very little fill time at TDC from a crappy rod ratio and need more flow velocity because the intake ports are too big for the midrange flow, and you want midrange at the expense of top end (less flow up top) , and do not plan on sabotaging the effects of the bigger cams like Toda B's or Jun 3's, then this is something to get .


[Modified by Michael Delaney, 7:16 AM 9/6/2001]

 

 

Michael,

Good post.. I would still like to see this put to the test with some tests.

Has anyone done this?

Regards,

 

Will not help with a 1.8 B18. Just like they said

 

just curious, but how can simply changing the length of the rod decrease piston speed? The piston is still covering the same distance (same stroke), and 2000 rpms is 2000 rpms regardless of the length of the rod, so how? Also, how does it increase dwell at TDC? Thanks in advance.

 

I think the length of the rod affects the dwell time because of the angle it is at in comparison to where the crank is at in its revolution. So if your rod is shorter, and your crank has moved about 1 inch in its revolution it is going to be at more of an angle than a longer rod would be. This would mean that it would have to pull the piston away from TDC quicker to compensate.

If I am wrong please correct me.