Cam Questions

[MikeBergy]

Maybe yall think I am nuts, but I am building my b16a to be a high revving monster. I am talking 12k. I understand all of you are going to tell me I am stupid, and all that jazz, so just spare me. I want the revs of my cbr under my hood. I am going to build my block to handle the stress. My question is, are there cams that make power in this rev range? just wondering. I am thinking of get my aebs sleeves nitrided while I am at it when I get my block done, to cut down on the friction and what not, as well as some other things to cut back parasitic power loss. Are there cams that will make power up there? There have to be. I am going to use my skunk2 stg2's as a starting point.

 

[phunky.buddha]

I'm sure there are cams that will be efficient up there- current cams on the market can breathe to 10k on a 2.0L block, so there's no reason why those same cams can't breathe to 12k on a 1.6L block. Less overall air would be moving through the engine, so the cam should be able to flow it- you just have to start worrying about air velocity.

 

[radnulb]

talk to Rocket of M24X... m24x.zeroforum.com / www.m24x.com

 

[MikeBergy]

Well, the head will be ported, I am thinking of getting some of those swirled valves to improve the flow into the chambers. The itr IM is being portmatched to the head, so flow probably won't be a concern of mine. Mike, what exactly do you mean by being concerned about the air velocity? I am thinking, the more velocity the air has, the more KE it will have going into the chamber, and thus it will be less likely to reverse the flow. I was reading up on motoman, I don't know how credible he is, but I was reading one of his articles on porting heads. He was saying, the more velocity and thus KE the intake charge has, the more force it will take to stop the influx of charge air. He was saying that the air was actually still coming in the cylinders after the piston reached bdc and was moving up again. So I guess I am now also asking this: Does this sound right? I am guessing if I can just keep the intake air velocity really high, I can tune my cam overlap to take advantage of the high velocity charge at the higher rpms, and make power up higher than normal. Does this sound feasable with the Stage 2's I have now, or am I going to have to go custom. I don't think any extra lift from stage 3's are going to help me much more. As you said, I am going to be running a bored b16a (1.75L) and so I will be flowing less air than a 2.0L .

 

[phunky.buddha]

Sounds good to me. I was thinking more like veocity of air at higher revs, but you're right- it won't be any higher than a 2 liter running lower revs, like 9.5k rpm... air velocity will be governed by total air flow through the engine, not engine rpm. You'll probably be fine.

I don't know about cam choice.

 

[xj0hnx]

Call up someone like RS and ask about a custom grind.

 

[MikeBergy]

Who is RS?

 

[xj0hnx]

Originally posted by MikeBergy@May 29 2004, 05:48 PM
Who is RS?

RS machines

 

[MikeBergy]

Oh. Those guys, I haven't really looked into them. Anyone used their products before?

 

[Relix]

Originally posted by radnulb@May 27 2004, 12:10 PM
talk to Rocket of M24X... m24x.zeroforum.com / www.m24x.com

Rocket is the man! Is he still with Ef1? those M24's I had were awesome