SIDE-FC

My friend was telling me that you can remove the small butterfly valve in the throttle body, so that it increases throttle response. Does anyone know what i think im talking about, or where i can find a link on how to do this. Because i can feel the valve open at 3500rpm, and i definatly have more power after that. but. i was wondering how i can find a how to on removal of it, for better throttle response.

86' FC3S - GXL , 'ports open, no cats/res/ac/air pump'

Thanks,

adrock3217

Sorry but NO, you can NOT feel it open at 3500 rpm. You THINK you can.


The secondary throttle butterfly on NA's slowly opens as the engine WARMS UP, it is in place to keep you from going WOT when the engine is still cold. Sorry.

SIDE-FC

then whats that lag at 3500?

takahashiRyosukeFC3S

yeah it's refferred to as the "Throttlebody Mod" here - http://www.fc3spro.com/TECH/HOWTO/TBM/tbm.html that is the proceedure on a turbo, not sure if it will work for your NA. but READ IT before you attempt it.

as for the reasoning of the secondary butterfly valve: it is to prevent an inexperienced driver from bogging the engine off idle. the Dashpot makes that valve open slowly so any normal individual will not stall the engine. that is it's purpose it has very little to do with a cold engine. HOWEVER the cold start idle assist is removed during this process so there is actually a little something to do with a cold engine... just not the same thing.

TR

EDIT: the lag at 3500-3800 could be your secindary injectors opening and opperating. thus intantly changing the A/F ratio for a fraction of a second. but that is all just spectulation.

SIDE-FC

interesting... thanks,

slpin

iTrader: (9)

SIDE-FC

that is your 5/6th ports... not secondary injectors or throttle blades...


on your info, you said, ports open...

maybe you wired it open? that could be why... it is like you are in the vtec lobe all the time.... the engine doesnt get efficient till 3500ish

1SWEET7

iTrader: (1)

Yeah there is no reason to have your ports wired open, it just decreases low end torque. Another thing you could do to increase throttle response is get a cone filter and route cold air to a sealed box with the filter. Or you could play around with modding your stock box like I did, it "feels" like there is more response.

SIDE-FC

Yea, I think im just gonna leave it the way it is right now, i heard that those ports should be open if your taking the cats off.. i dunno, i didn't open them, it came like that when i bought it for a whopping $500!!1 but, never the less. This FC will do me fine until i sell my mx6, and pick up a turbo 2. Also i found a website that looks quite legit and says that it should run 15.5 1/4 mile time. is that correct? that seems a little fast for a n/a FC.

sar

iTrader: (1)

Actually, they're right, having your 5/6th ports wired open effectively decreases your low end power. The thing you heard about the exhaust is for s4s (86-88) as the 5th/6th ports open from exhaust backpressure - ultimately them staying closed from not having backpressure will kill your top end. However, if you follow the following link it will show you how to have low end and high end. Your car will be noticeably less torquey under 3500rpm without the cat, acv, and blower - unfortunately, by removing the acv and blower you've taken away an important system for the gain of 1-2 horsepower up top.
http://www.rotaryresurrection.com/ro...elec6port.html

No, NA 1/4 mile times are not 15.5 secs, but more in the range of 16.5 secs as posted in factory spec road tests. http://www.albeedigital.com/supercou...0-60times.html