As we move along in the builds we find out more information. I am thinking about heads, cams and LT's. What are your thoughts on locking out VS. limiting (ie the Comp Cams limiters)the VCT? Does anyone besides Comp have dyno data on the limiters?
In my opinion go with the limiters.
The 3V is a great performer because of the heads and the variable cam timing. With the limiters you can take advantage of this technology, while being safe at the same time.
Now, on another matter, I question the cost vs benefit of the aftermarket heads and cams on a s/c motor. That is alot of coin for 50-70 hp. I run stock heads and cams to this day because I couldn't justify spending $3500 on heads and cams. That would be 73,500 for you.
To further clarify, anyone who is N/A, heads and cams are definitely worth the time and money.
I will send a message over to Rick about posting up some of the dyno numbers we had. I know we did a test to show the difference between unmodified stock VCT, full lockout and with the limiters installed. The car I believe lost 15 or so when fully locked out but then gained back 20 from that number to put it 5hp over the original unmodified VCT setup. It went something like this-
Unmodified VCT- 365 HP
Full Lockout- 350 HP
Livernois Limiters- 370 HP
The car also had an issue with cam phaser noise, the all to familiar knocking and tapping noise. I know Rick has a video of it, its pretty bad. So we did the swap over to the lockouts and then limiters and the noise is gone and has not returned.
In my opinion go with the limiters.
The 3V is a great performer because of the heads and the variable cam timing. With the limiters you can take advantage of this technology, while being safe at the same time.
Now, on another matter, I question the cost vs benefit of the aftermarket heads and cams on a s/c motor. That is alot of coin for 50-70 hp. I run stock heads and cams to this day because I couldn't justify spending $3500 on heads and cams. That would be 73,500 for you.
To further clarify, anyone who is N/A, heads and cams are definitely worth the time and money.
I will send a message over to Rick about posting up some of the dyno numbers we had. I know we did a test to show the difference between unmodified stock VCT, full lockout and with the limiters installed. The car I believe lost 15 or so when fully locked out but then gained back 20 from that number to put it 5hp over the original unmodified VCT setup. It went something like this-
Unmodified VCT- 365 HP
Full Lockout- 350 HP
Livernois Limiters- 370 HP
The car also had an issue with cam phaser noise, the all to familiar knocking and tapping noise. I know Rick has a video of it, its pretty bad. So we did the swap over to the lockouts and then limiters and the noise is gone and has not returned.
At this point in the evolution of modifications to the VCT system I would say the the most full-proof fix is the full lockout. This is for anybody that wants to eliminate any chances of anything going bad. The limiter would be the next option as it allows for no loss in power while still avoiding the issues that go along with the factory VCT system. While we have used 100s of sets on cars at this point and went through a pretty intense testing phase with the limiters and have not had a single issue nor do we think there ever will be there is always the chance of some problem with anything that has moving parts. For the people that do not want any chance the lockouts are the best option.
I will send a message to Rick to get him to post that info.
Thanks
Mike Schropp
Hey guys, just got back in the office. I am having Rick round me up the dyno graphs to post up so that it is a little easier to see.
The phasers were knocking until we installed the limiters, at that point the noise went away. The installation is pretty straightforward. There are detailed directions with a picture to explain it. The tune would need to be modified to limit the max retard to 20 degrees.
I will get that graph posted up as soon as I get it. Then we can further discuss the data.
Thanks
Mike
Strange. I had lockouts in and phasers were quiet, and installed your limiters and the phasers started making noise. I'm chalking it up to the probability that the phasers were a problem prior to the limiters being installed.