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secondary runners

2K views 40 replies 14 participants last post by  pituala 
#1 ·
is there any way for you to change when the secondary runners kick in
my freind drove it the other day and was amazed it kicked in so late and told me that the honda v-tec had something the changed when it would kick in
 
#3 ·
i have heard that the vtec afc controller wont work on the spec-v's
 
#7 ·
sorry a bot cranky. been at work since 7pm and still have 6 hours left
 
#8 ·
also tired, you could telll by looking at the way i am spelling my words
 
#9 ·
well if there is something i would like to set the secondary runners to open at 3500-4000 rpms cuase i never really hit that high unless i'm running her wide open
 
#12 ·
yeah it would be nice to have something to have that kick in earlier. The only time that i really get up to 5000 is at the track.
 
#13 ·
what kind of nitrous do you have and how is it put in the motor?
I have a 50 shot of nx (wet) fogger before the intake
 
#14 ·
ok i think this topic has been beaten to death.. secondary intake runners this that leave em open...tie em up...lets make em kick in earlier like v-tec...blah blah blah.... its not vtec!!!!!! you cant control them with anything...there are noooo gains if you could open them earlier...theres a reason they open up after 5000 rpms. At 5000 theres enough velocity to be able to start an increase in pressure by technically enlarging the inner cross section area of the intake runners...although its not really like this, this is wat those secondary intake runners opening up simulate. You would lose low end torque and might possibly cause a decrease in intake air stream velocity by opening them up at a lower rpm...you dont want that
 
#15 ·
specjoe said:
well if there is something i would like to set the secondary runners to open at 3500-4000 rpms cuase i never really hit that high unless i'm running her wide open

opening the runner earlier or later would provide no benefit unless you could change the cvtc system to optimise the extra air. the runners could be made to open any time you want with a rpm window switch hooked up to the vias solenoid. btw I have dyno tested a car with the runners zip tied open and the car lost power through out the entire rpm range.
 
#16 ·
Maybe with cams we could see a small gain to open the runners earlier but otherwise, I think it's useless.

I add this page from the FSM to complete the infos too how the VIAS system works ;)

 
#17 ·
Mexmr10 said:
you cant control them with anything...
I agree with pretty much everything in your post...although, don't you find it interesting that toward the end of the FSM page angel listed you have the phrase:

It [VIAS control solenoid valve] responds to ON/OFF signals from the ECM
 
#19 ·
Another option would be to completly remove the selenoid and the vacuum actuator and use a step motor instead. Something like our electronic throttle motor that will allow precise degree of opening instead of a full close or open runners.

Setup like this as been done in the past for the Probe/MX6 3-stage intake manifold (2 sets of butterfly) and conversion kit are available on the market.

But this would required hours of tuning on a dyno to acheive full gain and would apply only with the actual mods on the car. But maybe for an N/A beast with full bolts-on including cams, that mod could worth of it...
 
#20 ·
angel2167882 said:
Another option would be to completly remove the selenoid and the vacuum actuator and use a step motor instead. Something like our electronic throttle motor that will allow precise degree of opening instead of a full close or open runners.

Setup like this as been done in the past for the Probe/MX6 3-stage intake manifold (2 sets of butterfly) and conversion kit are available on the market.

But this would required hours of tuning on a dyno to acheive full gain and would apply only with the actual mods on the car. But maybe for an N/A beast with full bolts-on including cams, that mod could worth of it...
Now that's the best idea about this subject I've heard up until now.
 
#22 ·
cortrim1 said:
opening the runner earlier or later would provide no benefit unless you could change the cvtc system to optimise the extra air. the runners could be made to open any time you want with a rpm window switch hooked up to the vias solenoid. btw I have dyno tested a car with the runners zip tied open and the car lost power through out the entire rpm range.

werd! what i have been preaching that over on thevboard...loss of power all the way up to where the switch-over would occur!
 
#23 ·
on a stock motor, like ive said a million times before, you would see no gains. on a built, cammed, valved motor with p+p or extrude honing, the airflow characteristics change quite a bit.

and theres no 12v relay garbage involved. when you hit 5000 rpm, the ecu grounds the circuit. which makes it a bit harder to control. you can ground out the y/g wire from the vias solenoid via a dpdt switch, but that's too hard to work in everyday driving conditions. try to find a way to have an automated switch ground that wire. and there you have it.

trust me, there is NO good way to do this. and if i get some time to dyno tomorrow, i'll see if it works. if not, no loss to me besides a $2 switch and some wire.
 
#26 ·
punkguy671 said:
on a stock motor, like ive said a million times before, you would see no gains. on a built, cammed, valved motor with p+p or extrude honing, the airflow characteristics change quite a bit.

and theres no 12v relay garbage involved. when you hit 5000 rpm, the ecu grounds the circuit. which makes it a bit harder to control. you can ground out the y/g wire from the vias solenoid via a dpdt switch, but that's too hard to work in everyday driving conditions. try to find a way to have an automated switch ground that wire. and there you have it.

trust me, there is NO good way to do this. and if i get some time to dyno tomorrow, i'll see if it works. if not, no loss to me besides a $2 switch and some wire.

instead of shredding the wires simply tie off the runners for a run or two.. then dyno 2 runs with them intact. if you are right about the airflow then you comparing the back to back dynos will show you where exactly you would want the runners to come open.

deja vu the vboard? ;)
 
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