I have made the decision to eliminate the VTCs from my engine. My to potential methods are: Putting in significantly stiffer spring so that the unit cannot move at all or disassmbly with welding. The welding option is attractive since I could position the inner portion of the VTC to a comprimise position between the full advance of a working VTC and the VTC in it's "off" psition (20+ degrees of overlap on and approximaely 10 degrees off. My car is an auto so some loss of top end could be tolerated. I am looking for feedback on potential problems with oiling of othr things that may bite me on these methods. The FSM indicates that when the VTC solenoids are off oil flows to drain and when on oil presurizes the VTC. To me it seems that if I weld the VTC and disconnect the power to the solenoid the oil flow would go to drain, not requiring any oil passage block off. Comments?

 

If you weld it, you may have problems because a slight weight imblance could vibrate the cam.

Have you considered putting an exhaust sprocket in place of the VTC?

 

Yes. The exhaust cam would require the machining of a pocket on the back side to maintain gear and timing chain alignment. Draw backs are: Reduced thickness of the gear body by approximately 20%.

If welded the VTC could be dynamically balanced. Several service shops for this.

 

Sounds like you have gone over all the details and have things figured out, let us know how things turn out.

 

For the cost and effort in that why not just rebuild them and chage your oil regularly. If you rebuild them correctly then they will last a long time.

 

Sounds good from the man who wrote the guide! I rebuilt mine following your photos and everything is tip top.

Wasnt there talk of bad springs in some of the rebuild kits? I guess thats the risk.

 

Can someone post the link to this guide you are speaking of?

Thanks,
Bryon

 

Here is the thread, it has the link for the write up in it.

EDIT:
http://forums.maxima.org/showthread....58751&t=462613

 

Yeah Aaron had some trouble with springs apparently but so long as you compare old and new and find the new to be much stiffer you should be ok.

Glad I could help.

 

what thread?

 

Yeah. The rebuild kit I bought was the same height and stiffness. But some people rebuilt theirs with springs that were the same height and the ticking didn't come back within 1K miles. Or maybe they didn't notice the new springs were taller.

Anyway, I recently bought new springs. I was able to get them measured before ordering and these are definitely taller than the measurements you and lanedrifters gave me in that other thread. In fact, I should bump that thread to give some additional information.

The new springs I bought both measure exactly 2.761" in height.

Your old springs measured 2.585" for one and 2.611" for the other.

lanedrifter's old springs measured 2.625" and 2.623".

My new springs are over an 1/8" taller.

I might do the rebuild along with tensioners that I bought within the next few months.

 

Haha , I swear I hit paste...guess not, anyway. http://forums.maxima.org/showthread....58751&t=462613

 

I wish I had thought to do the tensioners while I was in there,I know I will be doing them eventualy.

 

can't you just ground the vtc's?

 

Grounding the vtc's doesn't fix the core issue,a worn part,the ground fix only quiets the vtc temporarly,eventually they will clack again...


While i do wonder about the bypassing the vtc all together sometimes,i think the performance loss will be more than minimal,i believe a major loss in torque would be felt throughout the rpm band..

With that said,I think rebuilding them correctly with the taller spring as aaron mentioned here is the best option for the ve.

 

Thanks for the comments everyone. Partly what is driving me towards eliminating the VTCs is my future plans for the engine and an inherant need (a sickness really) to feed an engineer's brain by doing "one off" projects.