[This message has been edited by Raydar (edited 11-16-2017).]

quote Originally posted by Joseph Upson: I disagree, those who locked cams on VVT engines did so for several reasons, none of which was ignorance in the true meaning of that term. It was an alternative to the exceptional amount of expense required to set a VVT engine transplant up as designed during a time when the technology was still very new in the aftermarket, at least in GM production cars and the likelihood of being at the mercy of someone else with the necessary equipment to edit programming which could be expensive and time consuming and I refuse to do that.

I said most people, not all. When people started grabbing truck motors out of the yard and deleting VVT, there was a lot of ignorance about how VVT was worse for performance engines (and really, there still is a lot of that ignorance floating around). This has been by far the most prevalent "reason" I've seen used. While it's true that many people are doing swaps using DIY ECMs that may not necessarily support VVT, it is not the excuse used for deleting VVT in most cases. In fact, so many people have done VVT deletions on LSx engines, that they actually made it more difficult to find accurate information on the technology for a while. There is still a lot of misinformation out there, but now that there's plenty of aftermarket VVT cams on the market, it's at least a little less difficult to find such accurate information.

However, I still come across so many threads and videos claiming that VVT is worse for performance engines. This is just demonstrably false. VVT is better for performance, better for emissions, and better for fuel economy.

And regardless, i don't think VVT is the main reason people aren't swapping 3500/3900 engines in the Fiero, and not the topic of this thread.

quote Locking a VVT cam upright is a work around and my memory vaguely tells me it was you I believe that brought to light that some owners were converting their OE VVT LS motors to the non VVT OE version because they made more power, during a discussion here on this very topic. I could be wrong but I believe it was you as you're pretty knowledgeable on the topic.

If I did state this, I'm pretty sure I would have qualified that as "they are doing it because they believe it will make more power" rather than because it's an absolute fact that it does. Non-VVT camshafts can only be used to make power in a certain range. As most people installing camshafts in LSx motors tend to install big cams with wider LSAs, they might see a decently large enough peak number in the high end, but are sacrificing the low end to get it. Because of the wide LSAs and large durations these cams have, VVT would be somewhat problematic for many of these very large cams. However, these tend to also introduce other expenses such as needing clutches or torque converters which also sacrifice driveability. If they would cut back on the LSA and duration a bit, an LSx could easily make near the same peak numbers, but have a much wider powerband, and remain driveable on the street, as well as getting better MPG with lower emissions.

In my build, I'm doing exactly the opposite of what most of these people do with VVT. I'm retrofitting it into an engine which didn't come with it. I found a decent cam, but it was only in non-VVT form, so I took the numbers and had a custom grind made on a VVT core. My goal is to get at least 400 HP/400 lbs-ft at the crank, and 40 MPG highway, as well as being able to meet CA's SULEV standard.

[This message has been edited by dobey (edited 09-17-2016).]