Box Stock

Best Box Stock Torque Cam?

I

intimidator3

New member
Which is the best torque cam for box stock? I run a real small track. BSP2, BSP3, Holey Moses Cam, CL1, CLI improved, or CL2 or something else? Any info would be great. I have heard the original CL1, not the new one and the bsp2 may be my best bets.
 
In all honesty I don't know what it drops to in the corner, but the max is around 5800 to 6000. I just know that the corners are tight and it is real important to get off the corners. Whichever has the most torque is probably the one I will try.
 
The bsp2 works great for the rpm range you are trying to hit, it has good low end torque and makes good power up to about 6100 from what I have seen and experienced. This cam did best with 28-29* timing and a holy Moses carb on my engine, with a 3/4" weenie pipe and billet steel flywheel, box stock class. The bsp3 is what I have in my akra clone, with 32* timing, holy Moses carb, pvl flywheel and Dover fat boy .930 pipe. It seems to like the rpms more and does best at 6300-6400 rpm. Has great top end and good low end torque as well.
 
An engine produces torque and rpm, from which we calculate horsepower. A cam that gives you more top end is just putting out more torque on the top end.
With the understanding that you have the clutch stall at peak torque on the starts, then you want a cam with the most torque at that RPM. An engine that turns more RPM on the top means the cam is putting out more torque on the top. Now some cams are better on the low-end, and some cams are better on the top end. If a cam is better in both places, that's the one you want. So just saying, "I want a cam with torque" is a little vague.

Now many times, because the track has big radius' in the turns, you go through the turns with the rpm's above peak torque. In this case you may want a cam with better torque in that RPM range. In many cases, with this type of cam, you may have to give up a little somewhere else. Maybe on the low-end, maybe on the top end. Of course the cam with better torque, EVERYWHERE, is ideal, but that "ideal" cam grind is seldom reached.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory.(Al Nunley
 
Well I should have made myself more clear. I am looking for the best cam with low end torque. I don't race on a track with wide sweeping corners so my rpms don't stay up.
 
I tested the cl2 against a bsp3 last weekend on my dyno.
I found the bsp3 has lots of bottom end torque and didn't lose power until 6600. My cl2 loses power at 6200 and didn't have near as much low end torque
Ohhh and if you want low end torque stay with lower timing settings
 
DRS29 said:
Ohhh and if you want low end torque stay with lower timing settings
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We only advance the timing to improve the performance in the upper RPM range. These engines are designed to produce max torque at low RPM they are utility engines, when we move up the RPM range you find that usable power drops off the scale drastically, this is when cam and ignition timing is used to move the usable power.
 
sounds like you want the bsp3....good bottom end for the track that you describe.....and coming up off the corners is paramount. beat them off the corners and you can get a clean run on the straights....no math, just good common sense.....
 
go with the BSP3 and set your timing at 30-31*, try to shoot for 6400-6500 as your target RPM and you will be fine
 
Lots of theories and all can be valid..
Thats the good thing about these engines..
Different combos react differently..

I will eliminate one cam from your original list.. Our HMC-14 is much better in the mid range to top end..

When trying to build bottom end torque think about centerlines.. If you have the time and a cam twister work on advancing one or both lobes..
The original CL1 and BSP 1 & 2 were fairly advanced.. As the racers demanded more RPM's you should see the centerlines becoming more and more retarded..
 
So what you are saying jerry is that all along the rpm limiter has been the cam ? If we had a cam centerline rule thy stoped them from being retarded or advanced to much that rpm could be limited ? And rpm could be limited by a timing rule also ?
 
You are NEVER going to get anywhere by having a timing rule. Way to many ways to beat the system. To much time involved in tech and a knowledgeable tech person needed to determine if a cam has been twisted or no.
 
DynoDon said:
You are NEVER going to get anywhere by having a timing rule. Way to many ways to beat the system. To much time involved in tech and a knowledgeable tech person needed to determine if a cam has been twisted or no.
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This is actually my "favorite" rule in the clone classes... NO PROFILE CHECK... It lets the builders be builders... We have a max lift and max duration and we can work within those parameters... Sure makes engine building more fun not being stuck to a profile check...

When the rules were written, whom ever thought about adding the .200" duration check was a smart dude... LOL! If it weren't for that check, we could really design some cool lobes.....would he hard as heck on valve train, but would make more HP...
 
Seems to me that you would want to have a cam that had the most torque in the rpm range where you spend the most time. A flatfooted turn track might favor a cam with good top end Torque. A real tight track, where you spend very little time at peak rpm, might favor a low-end torque cam.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)
 
some things are meant to be teched and others need to be left alone.....once your going down the road to over teching and the whole process will fall flat on it's face....meaning that if you don't make it easy to tech and catch the rule benders, then the tech inspector is going to need a college degree and a machine shop to determine if the dang thing is illegal! The more they overthink the plumbing, the easier it is to stop up the drain.
 
All I'm saying is everyone wants to blame the springs for the rpm issues and the valve springs are a very very small factor in rpm. Very small
 
Coty Morrow said:
All I'm saying is everyone wants to blame the springs for the rpm issues and the valve springs are a very very small factor in rpm. Very small
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I could turn my clones 7100-7200 with a legal carb and cam if it weren't for the valve springs we have to run....they will cause float. Given the parameters we have to work with on AKRA clone rules, the valve springs are the "weak link" in turning more RPM's...

That being said, given the lift and duration restrictions we have per AKRA rules, why anyone would NEED to turn more than 6450-6550 is beyond me... maybe they just like the sound it makes or like to look at the tach after the run.

I think the AKRA engine rules we have are good in the area of cam and springs. Like I've said a hundred times before, and I'll say it again, the area in AKRA rules that needs to be worked on is the "compared to known stock part". Give us a measurement and let us blueprint to those measurements. Like on the throttle shaft, behind/underneath the butterfly: If I file that down to the minimum spec, it's illegal... Really?!?!? Because it has file marks instead of machining marks, that makes it illegal...

I keep hearing rules are to keep costs down for the average racer... Let's see... An average racer can't file his throttle shaft down to the minimum spec, but an engine shop with thousands of dollars worth of machinery can mill theirs and get there.... The bigger engine shops can also buy hundreds of stock parts and cherry pick them... the average racer cannot afford to do this... So really, these "compared to known stock part" rules are in the favor of the average racer...? LOL! It's a farce.
 
NCStratos288 said:
So really, these "compared to known stock part" rules are in the favor of the average racer...? LOL! It's a farce.
Click to expand...
on the whole I would agree with you, but there are some areas that the, "compared to a known stock part" rule works out pretty good. The crankshaft is one of them.

IKF has a rule very similar and a friend of mine was disqualified because his crankshaft had extra counterweight in it. My friend put forth the argument that there was no rule that said you couldn't do that. I just reminded him of the, "compared to a known stock part" rule. Obviously having extra counterweights in the crank did not comply with this rule.

But I see your point about the rich guys being able to get around this rule. NASCAR once had a rule against balancing engines, so the factory sponsored guys would get boxes of Pistons and weigh them until they found a matched set. The poor independent guy, and in those days there were some, didn't stand a chance.

It would be interesting to see some real tightly controlled dyno tests to determine if the diameter of the shaft really makes a measurable difference. There is so much disturbance in the flow in that area, it makes me wonder. I know, just looking at it, it would seem apparent, but is it really.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)
 
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