solid roller cam
Racer
Joined: Jul 2004
Posts: 254
Likes: 1
Way to large of cam for a street car unless you are looking at making power around 7500 in that CID.
Quick and Dirty:
Lift is the ability to make power.
Duration is the ability to sustain power at a given rpm.
Higher you want peak power the more lift and duration is needed. This takes away from the low rpm operating range and hurts driveability.
Quick and Dirty:
Lift is the ability to make power.
Duration is the ability to sustain power at a given rpm.
Higher you want peak power the more lift and duration is needed. This takes away from the low rpm operating range and hurts driveability.
Race Director
Joined: Apr 2000
Posts: 17,672
Likes: 199
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
If you have deep pockets go with shaft rockers. Once you go there you will never come back. I check my lash all the time and I have not touched it in 2 years now with a T&D shaft rocker setup.
There's a reason they are expensive but now that I have had the setup for three years I can understand why. Complete valve train stability, revs to 7500RPM's and I haven't had to touch it in 2 years. I take the intake off twice a year and everything looks brand new, lifters, pushrods etc.
There's a reason they are expensive but now that I have had the setup for three years I can understand why. Complete valve train stability, revs to 7500RPM's and I haven't had to touch it in 2 years. I take the intake off twice a year and everything looks brand new, lifters, pushrods etc.
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
Surely isn't duration 'kinder' on valve train components than perhaps excessive lift. By having more aggressive opening/closing ramps on cam and opening valves quicker and closing them later this would increase the total time inlet valve is open without possibly 'hurting' low end drivability too much (as in a 'roller' cam supposedly). The fuel/air volume drawn in to the cylinder would be of a greater volume and arguably have a similar effect to increased valve lift. Knowledge of cylinder heads flow rates is also of importance - little point having higher valve lift if ports are unable to offer worthwhile additional flow as a result of increased lift. Perhaps someone at some point someone will offer desmodraulic valve operation (as per Ducati) so the 'lifter' will follow a far more aggressive cam profile or even better a 'camless' solenoid or pneumatic operation. Whatever happened to the company some years back who made 'trick' dual inlet valves for BBC's and built-up Harleys with a extra cylinder (W3's ?) - was it Gary Fueling ?
Last edited by roscobbc; Dec 12, 2012 at 06:22 PM.
Racer
Joined: Jul 2004
Posts: 254
Likes: 1
You can add duration to supplement for lift. We do this in limited classes all the time but as with everything there is give and take. What this does is narrows the powerband on the engine giving you a steeper power curve. Deep gearing is then needed to compensate for that.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Authorities other then moderators lol. I'm still trying to figure out my lawnmower. Next week im making my first cam out of aluminum i figure the weight savings will help. Probably gun drill it like those LS engine cams for even more weight saving. I also want those aluminum retainers chevy used to sell over there counter. If your going to blow up go all the way lol.
Last edited by Little Mouse; Dec 14, 2012 at 01:01 PM.
