Coyote VCT Function and Tuning

[kris5597]

Hey Guys,

I am about to dip into my ECU and I am concerned on a few things that I am not 100% sure about yet.

First is the VCT function of the Coyote engine. I am confident in tuning the vehicle for for ignition advance and fueling, however the VCT function I am a little confused on. It appears the intake valve opening time reads in (-) values and the exhaust closing time reads in (+) values. According to the Ford PCM, does that actually mean advance VCT timing and retard VCT timing or is the negative and positive values cam angle adjustments based on TDC to the crank shaft and both VCT tables are actually reading in advance VCT. ( I hope that wasn't too confusing).

My other question is, tuning partial throttle. I have been informed mapped points during partial throttle operation are what to target for tuning, but what exactly would I be adjusting to better fuel economy, throttle response, and partial throttle acceleration? I am assuming ignition advance and VCT tables, because all fueling is targeting stoic and changes with the amount of load that is on the car.

I have seen a few dyno graphs that have really solid torque gains on the low end as well. I am wondering if VCT adjustments are made there as well or if its only fueling and ignition advance.

I have tuned various engines for years, however, none of them have dual VCT on both intake and exhaust cam, its normally only the intake cam. Bracketing cam angles are the best way to go to find the best intake cam advance for RPM break points. However, having control of both intake and exhaust seems like bracketing could be quite interesting.

Kris

[kris5597]

NVM, the idea of how the VCT works on this engine just popped into my head, it's so obvious, sorry about that guys.

I just need partial throttle assistance.

Kris

[kris5597]

This forum seems pretty worthless...

[redline5.0]

This forum seems pretty worthless...

That will get you the answers your looking for in no time I'm sure.

[kris5597]

I'll figure it out i'm sure. Just wanted to get a jump start before I get behind the software. Datalogging and seeing what parameters the car is doing at different load and rpm breakpoints will point me in the right direction to find out which tables are being adjusted, from there its determining what changes will be made to better or worsen the improvements I am looking for. Partial throttle is all going to be by feel anyway, not realistic to do on a dyno unless I have it for an unlimited amount of time.

Kris

[wbt]

This forum seems pretty worthless...

Instead of criticizing others you should do some self help first such as searching the forum for mapped points. Plenty of info out there for those willing to make an effort.

[kris5597]

So far you guys have just further proved my point of the forum being worthless lol, searching for information has been done. That's all I do is search for information. Just because I search for mapped points, doesn't mean it's going to point me in the right direction. There are so many vague threads and questions on this forum, good and valid information seems that its hard to come by. If everyone on here is like this, I wouldn't share valuable information either.

I was not criticizing others, just the forum in general. Loads of people have viewed my thread either looking for an answer to my questions, not knowing the answer, or just ignoring it all together.

[wbt]

This took about 3 seconds to find:
http://www.hptuners.com/forum/showth...-Ti-VCT-Tuning
http://www.hptuners.com/forum/showth...-13-mustang-GT

You will also find threads with files attached. You should start by doing a compare of those files to stock and see what is changed. Then look for an understanding of why. That is where most start. This forum contains quite a bit of valuable info and people who are willing to help. Criticizing the forum is the same as criticizing those who are active participants and won't get you very far.

[kris5597]

I appreciate you taking the time to do a little searching for me, but neither link provided information and knowledge that I didn't already know. The first link, quickly hit a dead end of what could have been a good thread based on the title, then it followed to another link that explained tuning ignition advance on engines with variable valve timing, not the information I was looking for. Now, this is sort of going down the right path, but not exactly.

The second link seemed to involve a discussion of ghost cam. The last thing I want to do is create excessive overlap at idle just to get the car to sound like a crammed push rod motor.

Was my original post confusing on the question that I was asking? I am not being rude or sarcastic.

TBH, on an entire forum, your the only one that has posted anything to make this an active discussion, which don't get me wrong, I'm thankful for, finally going down some path of direction.

[kris5597]

Have you ever heard of bracketing cam angles? I feel as if most don't and if they do, they don't understand it and don't tune with tuning VCT to maximum efficiency.

[kris5597]

Possibly wording my question differently to what my overall goal is. The stock tune is great to me, except at WOT. Some refinement can be done but for the most part it's great.

My main questions is, can there be a fuel economy improvement at partial throttle. I know completely how to tune this engine at WOT to get everything I want out of it. I know possibly adjusting VCT at cruising speeds could change some things for the better or worse. I know it's a V8, but it's efficient V8, so I'm curious if anyone has had any luck tuning better mileage out of the car.

Kris