sideways_Into_3rd

the springs will handle 6500 rpm as well .. not to worry .. the only thing that i might spend more money on would be lifters .. you dont have to .. but stock lifters would probably bleed off around 6200

for rockers, i'm gettin a set of crane golds (same ones that come with the kit) from mike soon .. i was gonna keep 'em but we'll see how bad you want them sandeep

smokin1

I'm interested if your other possible takers fall through

sideways_Into_3rd

only other possible taker is sandeep .. lets see what he says

Draco

No.

a 112 LSA tightens up the powerband. The higher the LSA the larger the TQ peak but the narrower the band.

A tighter LSA brings the IVC (intake valve close) valve event closer to BDC (bottom dead center), but increases overlap. The IVC timing is the primary factor for how high in the RPM a cam peaks, while overlap helps determine the size of the peak. An earlier IVC will peak lower in the RPM.

Therefore a CC305 will rev higher due to a later IVC event which results from a couple degrees more duration and a wider LSA.

SBainsTA

So thats why a cc305 sounds lumpier? hmm From what I heard the power difference between the two is negligible.... Payam, call me when you get a chance, either on my cell or a t work 604-527-9257.....

Draco

they should sound roughly the same, their overlap is very close. The 305 has slightly more duration, but the lobes are a little more seperated. This would also mean that the torque peaks would be similar in height, but the hotcam will make a little less peak power (like 2-3 hp all other things being equal) at a slightly lower RPM.

sideways_Into_3rd

No, your wrong

the lower numerical LSA, the looser the separation the higher the hp band gets pushed. thats why NA cams have low LSA, ie 110 and lower and rev to the moon.

more overlap will make more power in the upper rpm due to exhaust inversion (not sure exactly what its called) when the exitting of the exhaust creates some vaccum in the cylinder to acheive %100+ volumetric efficiency NA. on the other hand, it costs the cylinder pressure to bleed in the low/mid rpm causing the lack of torque

thats why blower cams are all really tight 114+ lsa

Draco

Sorry man but you are wrong.

LSA = lobe seperation angle. a numerically lower LSA brings the intake lobe peak and the exhaust lobe peak closer together.

This tighter LSA increases the torque peak but shortens the powerband - thats just the way it is. N/A cams go with tight LSA's because they want to maximize TQ within the powerband they are designed for.

Please read this thread on LS1tech... it will take a while to read through the 250+ posts, but you will get a better handle on how the different valve events affect powerbands and TQ peaks, etc.

http://ls1tech.com/forums/showthread.php?t=101100

The exhaust suction on the intake charge is caused by overlap, which is based on IVO, EVC and LSA. You are right, this does improve VE, and thus the TQ peak, which is what I am talking about. However, this alone does not determine powerband, just the size of the TQ peak. Powerband is determined by how long after BDC of the intake stroke the intake valve closes, which is based on duration. Again, read that thread and you will see what I am talking about.

And to achieve 100%+ VE you need "Inertial supercharging", which is based on RPM and the IVC event I have already talked about. Basically the faster an engine revs, the more force it applies in pulling the air slug in to fill the cylinder. This gives the air more inertia at high rpm. Having a longer duration allows more of this air to enter the cylinder even after the piston has hit BDC and stopped pulling on the air. Hence, why the IVC event (which contributes to the duration figure) is the most important event to consider when determining powerband. And remember that tightening the LSA actually closes the intake valve earlier, thus lowering the powerband! Hopefully you are seeing it now...

93formula

sideways_Into_3rd

actually .. not really .. I still stand by my word and thing craigo is wrong .. i just dont feel like arguing over the net anymore

i'll just kick him square in the nuts tonight

93formula

did you even read that long *** thread??? that stuffs way over my head, im not even gonna bother arguing

bunker

You are both right.

93formula

then they both each other

KA0S

It was my understanding that a lower LCA, the higher you had rev the motor to take advantage of the cam....say 4k to 7k. Where higher LCAs was more for low end power in the 3k to 6k area.

Cam tech=

Draco

Yes and no. a tight LSA will hurt bottom end but once you get to the powerband (which is narrower due to the tight LSA), the torque peak will be nice and strong, but it will drop off fast once you pass the peak. higher LSAs will help bottom end power and top end power past the TQ peak, but they dont have a pronounced TQ peak.