Nissan 370Z Forum - View Single Post - Throttle-less VQ37 discussion

Waxhaw510 · 01-28-2015, 05:30 PM

I'm an electrical engineer and formerly worked in the auto industry (tier 1, variable cam actuation), have done some tuning in the past, but am currently way out of my comfort zone with this latest idea and need the help of the forum subject matter experts.
This is for consideration of a new engine for my currently SR-powered '69 510.
It's my understanding that the VVEL on the VQ37 controls lift all the way to zero, and is therefore used for the majority of throttling duties during normal operation. I've read that the main throttle is only employed during traction control events or to boost vacuum for brake assist. This is similar to many other engines employing direct or indirect valve control, BMW, FORD, etc. Since my car has neither traction control or vacuum assisted brakes, how would I go about controlling the motor ONLY using the VVEL servos, with NO main throttle(s)? I can't imagine this would be possible using the stock ECU, maybe I'm wrong? If I built a manifold that feeds the six intake ports through a common MAFS I could run it with any stand-alone as long as I can work out the control signal going to the VVEL servos (CAN perhaps?). On the other hand, it would be so cool to just run individual bell mouth stacks directly to the head (how strange would that look?) but with no throttle speed density is out of the question I suppose. Maybe a new approach, mapping fueling 3D using VVEL position (vie position feedback, not the request signal), RPM and well, not sure what the 3rd air reference would be.
I guess the natural question is WHY? Not sure really, there are some slight response and efficiency benefits, but maybe just because it would be pretty novel to see 6 velocity stacks with injectors (maybe in a strange top-down arrangement) and no throttles.
Let me hear your thoughts, is there a way that this could work?

01-28-2015, 05:30 PM	#1 (permalink)
Waxhaw510 Base Member Join Date: Jan 2015 Location: Waxhaw, NC Posts: 3 Drives: '69 Datsun 510 Rep Power: 10	Throttle-less VQ37 discussion I'm an electrical engineer and formerly worked in the auto industry (tier 1, variable cam actuation), have done some tuning in the past, but am currently way out of my comfort zone with this latest idea and need the help of the forum subject matter experts. This is for consideration of a new engine for my currently SR-powered '69 510. It's my understanding that the VVEL on the VQ37 controls lift all the way to zero, and is therefore used for the majority of throttling duties during normal operation. I've read that the main throttle is only employed during traction control events or to boost vacuum for brake assist. This is similar to many other engines employing direct or indirect valve control, BMW, FORD, etc. Since my car has neither traction control or vacuum assisted brakes, how would I go about controlling the motor ONLY using the VVEL servos, with NO main throttle(s)? I can't imagine this would be possible using the stock ECU, maybe I'm wrong? If I built a manifold that feeds the six intake ports through a common MAFS I could run it with any stand-alone as long as I can work out the control signal going to the VVEL servos (CAN perhaps?). On the other hand, it would be so cool to just run individual bell mouth stacks directly to the head (how strange would that look?) but with no throttle speed density is out of the question I suppose. Maybe a new approach, mapping fueling 3D using VVEL position (vie position feedback, not the request signal), RPM and well, not sure what the 3rd air reference would be. I guess the natural question is WHY? Not sure really, there are some slight response and efficiency benefits, but maybe just because it would be pretty novel to see 6 velocity stacks with injectors (maybe in a strange top-down arrangement) and no throttles. Let me hear your thoughts, is there a way that this could work?