hybrid engine cam phasing!!!

[kuzman83]

Call me crazy but I recently read an article about a proto daytona with the
16v engine and cam phasing. got me to thinking about how to reliably phase the cams on one of our hybrid motors. please don't flame my idea but input is definately welcome. My idea is predicated on the idea that a DOHC engine makes more low end power and less top end power with an advanced exhaust cam. conversely it makes less low end power and more top end power with a retarded exhaust cam. now... my idea is to fabricate a bracket to mount a spring loaded serpentine belt tensioner that places tension on the timing belt in between the intake and exhaust cams. then fabricate a second bracket for a second "oil pressure sensative" tensioner to be mounted above the regular tensioner (7 o clock position relative to the exhaust cam). obviously you would need a longer belt with a slightly larger amount of slack to allow for the phasing of the exhaust cam. So in theory, at idle, the spring loaded tensioner on the top of the engine would be taking the belt slack thus rotating the exhaust cam forward, as engine RPM increases, the oil pressure sensative tensioner increases it's tension, offsetting the spring, and rotating the exhaust cam counterclockwise/retarded until the belt slack is taken up and all slack is being taken up by the oil pressure sensative tensioner. I feel like this would move the peak torque/power curve much lower into the RPM band and keep it at peak torque/power for longer/further into the RPM band. Any thoughts? I think it could work quite well but I'm not the most experienced guy in the world so lets get this theory off the ground together!

[turbovanman²]

I don't like the idea of playing with timing belt tension, things can get ugly.

I can't find the story with the phaser.

[kuzman83]

I don't like the idea of playing with timing belt tension, things can get ugly.

I can't find the story with the phaser.

the story with the phaser was in an article that someone scanned into their computer out of a magazine and posted on here. when i get home from work i'll search for it.

[Murphy]

I remember seeing that idea a while back, sounds like a cool idea Does only messing with the exhaust make a big difference or does the intake matter much too? Here's a diagram of the way I remember it being setup. I got the tensioners mixed up, duno how much of a difference that would make. I was thinking of the tensioner being the the other place because I was thinking of using a timing belt tensioner like the 3.0 v6 has with the arm and spring to allow a great deal of movement. I thought that would mount better/easier on the side than the top. the oil part would be hard I think. If you can get the tensioners mounted up, I would rig it up to work with a manual choke cable or something to make sure everything works properly. Mainly so you can drive with it and see how it feels first. I can't wait to see the progress on this!

[kuzman83]

well the idea of which one makes the bigger difference is what I want to test. First I need to get a hybrid engine running good, then take it to the dyno and adjust the cams one at a time (adjustable cam gear). adv ret exhaust cam then adv ret intake cam and note the differences. The oil pressure idea is not as difficult as you might think. Mitsu 2.0 engines have an oil pressure sensative timing belt tensioner set up, as well as the 2.4 chevy cavalier engine and someone told me that a 95 mazda MX6 has something similar but that has yet to be confirmed. I have been dreaming this up for quite some time now so it's closer to feasable than you might think, I just wanted to make sure I'm not missing anything huge. I just think that no matter which cam is being phased, this could have the potential to really fatten a torque curve. I picked up a common block and 2.5 crank today to start my build. I already have a head so just a few more pieces to go. The other question I just thought of is this, the 2.5 already makes a substantial amount of torque v.s the 2.2 I wonder if the system will be more effective on the 2.2 or 2.5?

[1BADVAN]

cool idea i will be watching to see if you get anything working

[Directconnection]

I can't find the story with the phaser.

Simon, it's in the magazine I gave you 4 years ago! Remember? The "Ultimate" Daytona

[turbovanman²]

Simon, it's in the magazine I gave you 4 years ago! Remember? The "Ultimate" Daytona

Hahahahaa, sure, lol, but seriously, need to go find out where the hell I put it.

[zin]

The Ford Escort/Focus has a exhaust cam "phaser" that I thought might be adaptable to our engines, though I was thinking of the 8V for simplicity's sake, but it might work even better on the twin cam... This is basically an adjustable cam gear that uses engine oil and a solenoid to adjust cam position...

Mike