I appreciate the replies. I'm trying to get to 600 rwhp with those mods.
Generally speaking; boost is nothing more than a restriction
to air flow, as well as Volumetric Efficiency, given as VE%.
Generally speaking;
as boost goes up, VE% goes down.
As you relieve the restriction within the induction system,
one then finds that VE% goes up, as will the value of
HP & Torque. Also, one will also typically find that as
one relieves the restriction within the induction system,
that the Peak Engine RPM for both HP and Torque, will
tend to move up withing the Engine's overall RPM Band.
***This is highly dependent on the 'discharge coefficient' of the heads.
Or simply put;
Window Area / or Curtain Area= Valve diameter * Pi * lift
Window area * 146 = theoretical maximum flow for that area, or
'Curtain Area'.
***Some, as I do, most usually will use the value of 137 cfm / Sq", per SAE,
rather then the higher value of 146 cfm ' Sq." of flow.
Take your flow and divide it by your theoretical maximum.
This is the ratio of effective flow area to actual flow area
This is your discharge coefficient.
And our cylinder heads do not perform well against the criteria of the
discharge coefficient, as our intake ports do not stand straight up. . .
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How much torque the engine makes, and at what engine rpm, tells
you at what engine rpm said engine is most happy operating at.
While large duration camshafts have their place
with larger CID Engines, having a longer stroke
then does our 376 CID LSA Engine. . . .
. . . . .Excessive duration camshafts don't help here with our
376 CID Engine, as they tend to lessen VE%, not increase it,
unless one desires to spin these engines beyond their ability
to do so, especially with hydraulic lifters. . . . .
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You shouldn't have any problem getting +600 rwHP with the stock blower,
and a mild cam, assuming you configure the pulley ratios correctly, use the
correct fuel, and have someone tune it, who has experience with these
engines.
600 HP equates to about (600 * 1.5)= 900 cfm required,
to fill the cylinder, to make that much HP.
The stock blower can put out a bit more than that, if asked to.
It can usually provide for (660 * 1.5)= 990 CFM, to 1050 CFM,
which is good for ~(1050 / 1.5)= 700 HP.
Your stock cylinder heads flow about 290 cfm @ 28" of water drop.
And. . .(290 * 4)= 1160 CFM.
So with the simple info above, one can see how some of
the important pieces begin to scale for. .
HP.
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E85 is the best fuel for these engines, as it is an oxygenated fuel. Along
with a well thought out 'mass flow' recovery system, the engine will run
cool, in spite of the fact that a modified engine, is putting out more HP then
does the stock engine, so you should be good to go..
I would think about 660 HP could easily be produced,
which represents about an 87% cylinder fill.
Quantitatively, regarding the cylinder head performance,
shows it calculates out as. . ..
=> (660 / 290)= 2.28 HP per CFM.
Here a value of about 2.4, for gasoline is very, very good.
Using an oxygenated fuel, you cheat the induction system
though, as you move the oxygen into the engine, via the
fuel pump(s). This is why it is so very important that one
chooses / purchases the correct fuel system.
And HP per CID. . .
=> (660 / 376)= 1.76 HP per CID.
Those are very good numbers for 'Street Iron'. .
Good Luck to all of you new members / posters. .
RD
