VRIS Under boost

chdesign

Member
Was flipping through the Probetalk forums and came across a thread about this.....they have found soem pretty big gains by either tying the butterflys open or taking the entire assembly out. One Probe GT guy saw gains of 17 Hp by doing this. Just a thought for me and you spoolin we may want to try this.
 
Interesting....Do u think we will ose a lot of bottem end and torque if we do this?
Also how would u physically tie up the butterflys?
 
I don't think we would lose much bottom end due to the F/I and to tie them open just use some zip ties and disconnect the actuator.
 
Let me know spoolin if it proves effective on the dyno I will just take the butterfys out of my intake runners.
 
Hey...I saw that last week on my engine...I plan on seeing if it makes a difference while NA...i'll do that on the dyno too.
 
NA it will probably kill your low end. FI it wouldn't doso since we are forcing in air and you are still sucking air.
 
I thought that the butterfly valve regulated the air intake. Wouldn't opening it all the way make the mixture run lean at low RPM's and cause detonation. That would be bad
 
hangin' with the big boys!

Actually, opening the butterfly valves would cause an influx of self-actualized gasoline to atomize within the cooler air. The mixture would not be detrimental because the increase is braking would cause the excess heat in the brake lines to reversely osmosize the intake manifold, thus preventing the hybrid gasoline-oxygen molecules from splitting. Once this combination passes into the combustion chamber there is a slight detonation, but not enough to prevent the valves from offsetting their timing belt. The effect this has on your bottom end is dependent on what type of seat cushions you have installed. I do not recommend after-market cushions, unless you are running FI, then you will need to run intercoolers through your seat cushions to make up for the increase in heat due to compression. Thats what I did anyway.

Couldn't resist guys!
:D
 
Re: hangin' with the big boys!

slooper said:
Actually, opening the butterfly valves would cause an influx of self-actualized gasoline to atomize within the cooler air. The mixture would not be detrimental because the increase is braking would cause the excess heat in the brake lines to reversely osmosize the intake manifold, thus preventing the hybrid gasoline-oxygen molecules from splitting. Once this combination passes into the combustion chamber there is a slight detonation, but not enough to prevent the valves from offsetting their timing belt. The effect this has on your bottom end is dependent on what type of seat cushions you have installed. I do not recommend after-market cushions, unless you are running FI, then you will need to run intercoolers through your seat cushions to make up for the increase in heat due to compression. Thats what I did anyway.

Couldn't resist guys!
:D

I See! :rolleyes:
 
As far as what I know from working with Honda engines, we always used to take the intake manifold off the B18C5 and put them on our B18C1's for the benefit of a straighter intake path and the fact that the B18C5's intake manifold didn't have the butterflies. We would even see good improvements throughout the entire rev range when switching to the B16A intake manifolds (they have the same intake path as the B18C1 but no butterflies). Our cars were all setup for autox and road courses also so bottom end was important, from what I've seen butterflies are pretty much useless when you're driving at ten tenths.
 
OK everyone i tied mine open and it made a huge difference under boost. Better throttle response and smoother accells. Anyone going boosted must try this all you do is take teh vacuum lines off goign to the actuator and plug the holes its that easy.
 
if they are vacume operated cant you change the way or time they open at.
on my rx 7 the old carb had a secondary spring which i could change to open the secondaries earlier. is this the same concept or am i way off.
 
The are vacuum and solenoid controled. The vacuum of the engine holds it shut at idle while a solenoid keeps the vacuum line with negative pressure in it. Once at a certain RPM (3800) that solenoid opens and if you are under WOT then you have no vacuum in teh system so the butterflys open. You could make the butterflys open progessively but bypassing the solenoid but i just unplugged the vacuum line so that they are open all the time and plugged off the open vacuum holes.
 
I've got a buddy that has an integra gsr and he plugged his vaccuum lines and gained 2 tenths.. 15.1 to 14.9.. best time though was 14.6 only mod is a aem cai with no exhaust on the track.
 
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