Let's see if I'm understanding this correctly. On the demand side in order to get to 338 CFM, I'd need to be around 6965 rpm. The supply side, given the valve diameter/lift/duration, would flow the 338 CFM so then the supply/demand are then matched, Correct?
Now for the dumb question, if the two are matched how does the supercharger come into play or was it required to get to the 338 CFM for the supply side?
Also is the cam is going to play well on the street (i.e. still have descent performance on the lower end) vs being more on the max effort side? I assume the ICL would help determine this.
It's starting to make a little more sense why Lingenfelter uses a Kenne Bell 3.6L on their 900hp, pump gas engine since it's 376 cubic inches and it looks like they use a fair amount less lift and duration on their GT22 cam.
You wrote:
"Let's see if I'm understanding this correctly. On the demand side in order to get to 338 CFM, I'd need to be around
6965 rpm. The supply side, given the valve diameter/lift/duration, would flow the 338 CFM so then the supply/demand are then matched, Correct?"
Pretty much correct; however to generate 338 CFM of Piston Demand,
with an NA Engine, you would have to shift higher than that..lol
So then the question is; how much lower can you
shift when using a 'Roots Style Blower', as the blower
needs to fill the gap so to speak, between the piston
cfm demand (Demand Side) by forcing in air from the
'Supply Side."
But little 'Roots Blowers' are limited in what they can do. . .
-----------------------------------------------------------------
You also wrote:
"Also is the cam is going to play well on the street (i.e. still have
descent performance on the lower end) vs being more on the
max effort side? I assume the ICL would help determine this."
***You meant LSA not ICL.
Well now, I asked you the following question within my
post number 46. . .
"Are you going to have a problem with a rough idle?"
If your not going to like a rough / choppy idle, then
you might desire to consider a camshaft with a
wider LSA. However, with an exhaust duration
of 259°, widening the LSA is going to generate
some negative issues.
-----------------------------------------------------------------
You also wrote:
"It's starting to make a little more sense why Lingenfelter uses a Kenne Bell 3.6L on their 900hp, pump gas engine since it's 376 cubic inches and it looks like they use a fair amount less lift and duration on their GT22 cam.
Those Lingenfelter cams are very old camshaft designs.
They also used closing ramp rates / velocities
that hammered the valve train to death.
And yes, you can run both a lower flowing cylinder head, as
well as a milder camshaft when you use a real Supercharger
such as a Kenne Bell 3.6L "Twin Screw', instead of a
simple 'Roots Blower' which is nothing more than a big
fan which simply blows (hence the term blower) air into
the intake manifold.
So then; if one has a HP Number in mind when they begin
the build, there would be differences in how one would map
out the build when using a 'Twin Screw Supercharger', versus
a simple 'Roots Style Blower'.
-----------------------------------------------------------------
A suggestion for you.
Instead of going with the Jones Cam and using pump gas,
go with E85 and contact Matt / GP Tuning for your camshaft
and valve train needs.
Mike Jones is a very smart and very busy man who designs
camshafts for serious engine builders. He is one of only two
people I use to purchase my cams from when I was building
race engines.
Matt has built his reputation on helping the earnest 'Street Iron'
crowd, such as people like yourself.
Finally; E85 has an additional benefit that many don't
recognize. It burns quicker and cleaner than does
a cylinder head chamber filled gasoline.
When one has a
low static compression ratio as these
engines do, when you pack more and more gasoline
into that chamber, it takes longer for that fuel to burn.
Static compression ratios, greatly impact an engines
efficiency via the ASE%, as well as the burn angle.
-with e85-
Now you can use a high duration exhaust lobe to offset
the poor flowing exhaust ports we have on our heads,
and if required to maintain low engine rpm manners, we
can also spread the lobe centers (LSA / LCA) as might
be needed, and not lose energy still burning during the
blow-down event..
Cheers
