The title was inducive just so I can get your attention to my problem.

I know a lot of you fellow second gen owners, have wire your 5th and 6th ports open for better high end torque or to get rid actuators that are probably rusted and operate as you woudl like anymore.

Anyways, I need your help, since im concerned about gas milage issues. I haven't got my car yet, however before I put my car for a rebuild of both the tranny and the engine, I had a mild streetport done ( This is the second time my engine gets rebuild if you chekc back on my posts youll see what happen). Furthermore, the mechanic decided since i have bought a racin beat header, to take out the 5th and 6th ports and wire them open ( I guess air will be going all the time). Now I used to be getting around 16-18 miles per gallon. Hwo bad will this decrease my gas milage... anyone?

Sincerely, a HARD HEADED ROTARY ENTHUSIAST!

 

You also lose low end power.

 

Im aware of the low end torque lost, regardless of that my main concern is not horsepower nor torque; is gas milage for right now... An SAFC and some dyno time will help with that minimal loss later on... however im a poor college student and well im just a lil worried about it.

 

i have mine wired open right now because i just ported my intake and noticed that with them closed i have no power at all above 3500. before i ported it i usually left them closed because i like having a little more low end for daily driving, not redlining. i never noticed a difference in gas milage but like i said i only had them closed when i was driving around town so i wasnt getting on it. but if you like to get on it often i would suggest wiring them open, i noticed a little better miliage becuase your getting more air at high revs. just depends on how you drive...

 

bump , thanx mint87rx7

 

i don't think that will effect gas mileage at all. since fuel imput is based on air flow, and air flow is based on where the throttle is, if you drive the same way, then gas mileage shouldn't change. right?

 

When I wired my aux ports on the gsl-se, I saw no difference in low end torque or fuel economy. I always got 24mpg, all highway.

 

ALEX, no need to take them out. we can rig up something like what we did on my car with the lumbar pumps so yours can stay functional with the new header.

 

Um, take out the ports and wire them open?
You can remove the actuators and sleeves, but the ports will always be there.. if you take out the actuators and sleeves, what do you have left to "wire open" ? confusions here...
anywas, i removed my sleeves/ports ported the manifold and I leave the VDI closed. I enjoy this setup

 

whey on earth would you leave the vdi closed?
this is costing you probobly 20+ hp above 5000rpm. and dont try to argue your way out of it, its a plain fact. there is no down side to having functional vdi, WTF to you!

 

andrew it was not my choice to take them out. HE already took out the actuators and Im sorry i mean slevees not ports sorry about that. I got confused since the sleeves lay in the ports. thank you guys for all the input.

 

too bad my intake is completely different from stock form. Ive driven with my VDI closed and opened and i know for a fact that its not "costing" me 20hp. I would dyno this to prove it to you, but that would be a waste of money. They car had less torque with the VDI set to open at 5500. So i left it closed.

 

 

wtf. why are you confused.

 

Dunno where you got this idea, but it's wrong. There are no gains from wiring the auxiliary ports open, only losses.

 

Only "gain" in the sense would be a more bullet proof system without having to worry about old shitty actuators opening or not. Of course, a good cleaning and lubing and they would be fine

 

i have my s5 actuators for sale, with sleeves etc

 

haha damn...I guess ill get them back when i go pick up my car tomorrow. Ill post pics of my messed up housing and rotor.

 

so dezerte, what is so different about your intakes that have rendered the vdi worthless? porting certainly wont do it (mine are prety agressively ported and i get even MORE power in the vdi range now) unless you milled down manifolds (i dont see how you could anyway) to make a rediculously shorter intake path, the vdi will still save some use. if you arent feeling a power gain with it on, id be highly suspicous of something else being wrong with your car.

 

ITs useless to argue this. There is nothing wrong with my car. I think it has the same kinda effects as wired open ports at low RPM kinda thing.

 

alright. suit yourdelf. but aperently you dont understand what vdi is actualy doing.

 

OK, well on a 90 na, do you need your main cat to open the ports fully?
Or does having a stock exhaust manifold provide enough backpressure to open them if u had a "catless exhaust" & free flowing mufflers?
Thanks for any replies guys.

 

So why dont you explain what its doing?

 

I imagine with my setup, the VDI is more functional at a higher RPM than what the factory intended.

 

i got the car back... he closed the ports... I HAVE A LOT OF HESITATION as soon as it hits 1500 and up.