harlan RPM switch 00VI questions

[dandaman0139]

What is an rpm switch and do i need it for the 00vi swap?

[915max]

An rpm switch is an electronic component(switch) that opens(activates) the VI at a certain set rpm AND closes(deactivates) at another set rpm.

Its pointless to do the 00VI swap and not have one... so yes you DO need it.

[dandaman0139]

ty

[jmeister]

Stay away from the Harlan switch.Why you asking if you need one days after you posted your VI setup for sale?

[915max]

Get the MSD 8969 switch. I've had it for a little less than 6 months and it works great and reads the rpms very accurately.

[dandaman0139]

couldn't decide if i wanted to keep it or not but i decided not to put it in

[DjNikos]

good luck with your swap bro. RPM switch, I know I wouldn't use anything thats not 100% exact. I know for myself, Im going to buy the APEXI VAFC II. Its exact on increments of 100rpms. Its alot more expensive than a manual switch, but it definately is a pain to sit there and keep adjusting.

http://cgi.ebay.com/ebaymotors...wItem

[915max]

good luck with your swap bro. RPM switch, I know I wouldn't use anything thats not 100% exact. I know for myself, Im going to buy the APEXI VAFC II. Its exact on increments of 100rpms. Its alot more expensive than a manual switch, but it definately is a pain to sit there and keep adjusting.

http://cgi.ebay.com/ebaymotors...wItem

You wont be able to use the VAFC II as a rpm switch because it doesnt have an open and close option. In other words, the V-tec controller portion of the VAFC II opens up V-tec(the VIAS in our case), at a certian point, but then doesnt deactivate it until the rpms drop back down to a specific rpm range <--- and thats at deceleration.

What we need is a switch that will activate the VIAS to open up at a certain rpm range, and then close it at a later rpm range so it can allow for more top end....

If you use the VAFC II, all you will be doing is keeping the VIAS open once you hit your marked rpm, causing you to lose a lot of top end. The VIAS is used to produce more torque.

I tried the VAFC II and it did exactly what I said.... so now, I'm runnning off of my VAFC II, but using my MSD switch to activate the VIAS.

BTW, the MSD 8969 switch is on point... it reads the rpms at the same number as the VAFC II.

The 100 rpm incements you're talking abut is to adjust air/fuel corrections, not to read the rpm's. And I forgot to add that the MSD 8969 model is a DIGITAL switch. This switch can be mounted inside the car so you can adjust the settings of when you want the VIAS to open up.. I got mine mounted in the dash., or you can mount it in the center console compartment.

[DjNikos]

You wont be able to use the VAFC II as a rpm switch because it doesnt have an open and close option. In other words, the V-tec controller portion of the VAFC II opens up V-tec(the VIAS in our case), at a certian point, but then doesnt deactivate it until the rpms drop back down to a specific rpm range <--- and thats at deceleration.

What we need is a switch that will activate the VIAS to open up at a certain rpm range, and then close it at a later rpm range so it can allow for more top end....

If you use the VAFC II, all you will be doing is keeping the VIAS open once you hit your marked rpm, causing you to lose a lot of top end. The VIAS is used to produce more torque.

I tried the VAFC II and it did exactly what I said.... so now, I'm runnning off of my VAFC II, but using my MSD switch to activate the VIAS.

BTW, the MSD 8969 switch is on point... it reads the rpms at the same number as the VAFC II.

The 100 rpm incements you're talking abut is to adjust air/fuel corrections, not to read the rpm's. And I forgot to add that the MSD 8969 model is a DIGITAL switch. This switch can be mounted inside the car so you can adjust the settings of when you want the VIAS to open up.. I got mine mounted in the dash., or you can mount it in the center console compartment.

Well said on that man. Something I didn't know about the VAFCII. But Yeah, from what you're saying, you wouldn't even need the apexi. Did you get any benefits from using it with the MSD together with the VAFCII or did you just shoot money down the drain?

[jmeister]

The VAFC2 worked fine as an RPM switch for me and many others who have gone this route. You want the VIAS to open at like 5200rpm and allow for better top end. It will close on it's own after if falls back under the set RPM. You just didn't know how to use it apparently. Short runners = open VIAS better top end, long runners = closed VIAS better tq on the low end. That's why the DEK VI is better than the MEVI.

[lowblocks]

what's a vi

[95prmax]

You wont be able to use the VAFC II as a rpm switch because it doesnt have an open and close option. In other words, the V-tec controller portion of the VAFC II opens up V-tec(the VIAS in our case), at a certian point, but then doesnt deactivate it until the rpms drop back down to a specific rpm range <--- and thats at deceleration.

What we need is a switch that will activate the VIAS to open up at a certain rpm range, and then close it at a later rpm range so it can allow for more top end....

If you use the VAFC II, all you will be doing is keeping the VIAS open once you hit your marked rpm, causing you to lose a lot of top end. The VIAS is used to produce more torque.

I tried the VAFC II and it did exactly what I said.... so now, I'm runnning off of my VAFC II, but using my MSD switch to activate the VIAS.

BTW, the MSD 8969 switch is on point... it reads the rpms at the same number as the VAFC II.

The 100 rpm incements you're talking abut is to adjust air/fuel corrections, not to read the rpm's. And I forgot to add that the MSD 8969 model is a DIGITAL switch. This switch can be mounted inside the car so you can adjust the settings of when you want the VIAS to open up.. I got mine mounted in the dash., or you can mount it in the center console compartment.

see i realized the same thing when i had my oovi and my vafc ii. I discconected the vias from the vacf ii and i used an rpm switch from summit and that worked great... it is true that you need it to open and close all it is a boost of air to help you get a boost of power. then you dont need it what you need is your top end

[915max]

The VAFC2 worked fine as an RPM switch for me and many others who have gone this route. You want the VIAS to open at like 5200rpm and allow for better top end. It will close on it's own after if falls back under the set RPM. You just didn't know how to use it apparently. Short runners = open VIAS better top end, long runners = closed VIAS better tq on the low end. That's why the DEK VI is better than the MEVI.

There are a lot of other people who have used the VAFC II for their 00vi and VQ35's (experianced Maxima modifiers) and they can confirm the same thing.... I had the MSD switch first and that showed me results right off the bat! About two months later, I got a great deal on the VAFC II from a friend ($50.00) and installed it, removed the MSD, and the car lacked a lot of power, especially at top end. I tried adjusting the Vtec controller to open up the VIAS at all ranges 2000-6000 and it was no good.Maybe B.S to you, but I have gone both routes, and I can honestly say I have personally felt the difference.

BTW, VIAS made for torque, not top end.VIAS is naturally opened... so when the signal/vacuum is sent to the VIAS solenoid, it closes the valve. Check the fsm. it'll tell you!

[915max]

Well said on that man. Something I didn't know about the VAFCII. But Yeah, from what you're saying, you wouldn't even need the apexi. Did you get any benefits from using it with the MSD together with the VAFCII or did you just shoot money down the drain?

I havent tuned the car at all so the VAFC II is not doing anything for me.. just giving me hi-tek displays for no reason . I hope to tune it soon so I can actually see what the car is really capable of. My plans for all my racng mods have been at a stand still because I just purchased a house... I have the VAFC II waiting to be tuned, a custom 80mm MAF I made, waiting to be installed, and i'm in need of some tires bad!

The apexi is great! (even though I havent been able to utilize it). There's a big misconception of the VAFC II being used for a rpm switch on the 00vi and the VQ35 swaps that I think it was origianlly misintrepretated from a post that was made a long time ago on another Maxima website. The reason many are using it is for air/fuel corrections. Even one of the originators who used the VAFC II on the Maxima specified that it couldnt be used as a rpm switch.

[jmeister]

BTW, VIAS made for torque, not top end.

edit: wait, you have the 3.5 swap? Yeah the VIAS setup is basically opposite on those, I assumed you were talking about the 00-01VI

[915max]

edit: wait, you have the 3.5 swap? Yeah the VIAS setup is basically opposite on those, I assumed you were talking about the 00-01VI

Dont you also need a window/rpm switch for the 00VI swap!? If so then that means you need something that wil open it at a certain point and then close it at another point. I could be wrong though..

If the 00VI's butterfly valve is intended for top end purposes, then why not have it open at an early rpm range, like 4000-4500!? The VQ engines are torque beasts so you really wouldnt be hurting torque... plus you would gain a lot more top end power opening it up at around 4000-4500.

Just my two cents!

[jmeister]

Dont you also need a window/rpm switch for the 00VI swap!? If so then that means you need something that wil open it at a certain point and then close it at another point. I could be wrong though..

If the 00VI's butterfly valve is intended for top end purposes, then why not have it open at an early rpm range, like 4000-4500!? The VQ engines are torque beasts so you really wouldnt be hurting torque... plus you would gain a lot more top end power opening it up at around 4000-4500.

Just my two cents!

Yeah, the OP was asking about the 00-01VI so I figured that's what you had been talking about this whole time with the VAFC2. I finally clued in you had the 3.5 and was referring to it's VIAS. The VAFC2 works perfectly on the 00-01VI not on the 3.5, hence my dispute with you.

You'll have to dyno to find the right RPM set point to open the 00-01VI... usually around 5100. It will be closed under that RPM point with no signal from the switch. So it will open at whatever RPM you set it at and remain open until RPMs drop back below set point.Torque will suffer if opened earlier and the hp "curve" will not be smooth.

[915max]

Yeah, the OP was asking about the 00-01VI so I figured that's what you had been talking about this whole time with the VAFC2. I finally clued in you had the 3.5 and was referring to it's VIAS. The VAFC2 works perfectly on the 00-01VI not on the 3.5, hence my dispute with you.

You'll have to dyno to find the right RPM set point to open the 00-01VI... usually around 5100. It will be closed under that RPM point with no signal from the switch. So it will open at whatever RPM you set it at and remain open until RPMs drop back below set point.Torque will suffer if opened earlier and the hp "curve" will not be smooth.

So its resolved! LOL.....

00VI= can use VAFC II as a rpm switch02-up VIAS= can't use VAFC II as an rpm switch, but good for fuel corrections
Modified by 915max at 10:01 AM 5/21/2007

[dandaman0139]

thanx alot guys