JEC_31

Excellent reading- thank you for sharing!

toofast928

Thanks Greg!

slate blue

Simo that looks like some great info too, I haven't read it all as yet, David Vizard is very well regarded. The other interesting articles and I will try to get more info in the future is the engine masters. Engine masters is relevant because they use a max of 6,500 rpm and use the highest average power from 2,500 to 6,500 rpm to determine the winner.

Mind you these are not emission controlled engines, so that needs to be factored in. In some years injected engines fight with carburetor equipped engines, big relative power, in BMEP terms more than 200 psi at peak power.


Here's an snapshot of a Engine Masters engine, using Pipemax to analyze it, it is done by Larry Meaux who wrote Pipemax.

PipeMax Simulation of Tony Bischoff's 2007 Engine Masters Winning Engine


Tony's winning Engine made
673 Peak HP @ 6500 RPM
581 Peak TQ @ 5100 RPM

Cylinder Heads Flow Intake=345 CFM and Exhaust=230 CFM
note=> PipeMax calculated Tony was only accessing
between
Required Intake Flow between 293.8 CFM and 311.0 CFM at 28 Inches
Required Exhaust Flow between 185.8 CFM and 214.7 CFM at 28 Inches

Peak Piston CFM Demand @ 6500 RPM= 321.8 CFM
so the most Tony could have accessed at 6500 RPM was 321.8 out of 345 CFM

Quote from Tony
" We got it up to about 340 CFM on the intake;
i mean, its nothing crazy, but its not too bad
for what we are doing."

"The Head had really good mid-lift flow,
though anything after .600" lift
it just stalled really hard ."

Could it be the combination of the Port "Stalling"
at .600" Lift in conjunction with the most the
Engine could have pumped at 6500 RPM being 321.8 CFM,
...that all the Engine could effectively access
thru the Carb + Manifold + Heads was 293.8 to 311.0 CFM

Note that PipeMax is based off my FlowBench which is
10 to 20 CFM conservative and well as my Dyno is conservative.
This could be 303.8 to 321.0
or as high as 313.8 to 331.0
thru Carb + Manifold + Head

230.0 Exh CFM was enough exhaust port to go to 7500 RPM

Tony's Intake Port Volume CC's were = 230.0 CC's
this calculates to a 2.5399 average CSA
Pipemax=>
285 FPS Velocity CSA= 2.474 sq.in. at 6500 RPM Recommended Smallest Port CSA
260 FPS Velocity CSA= 2.712 sq.in. at 6500 RPM Recommended Port CSA

this is about whats needed to make such a necessary
very wide Torque Curve all the way from
2500 RPM to 6500 RPM


Also note Tony used a ProSystems Holley 1050 CFM Carb
PipeMax= 1078 CFM @ 6500 RPM

Tony used a 2.190 Intake Valve OD ... in my opinion that was
an excellent choice as it reduces the necessary peak Lift
to prevent Choke !!!

PipeMax also calculated Tony need to choose an Intake Manifold
with a Runner Length of at least a minimum of 5.219 inches long !
along with at least
Minimum Plenum Volume CC = 999.9 [typically for Single-Plane Intakes]


Tony's Headers were Kook's 2-Step design
1.750 and 1.875 3.000 Collectors

PipeMax calculated
2-Step Specs= 1.708 and 1.833 by 28.8 to 31.7 long
Collector= 3.139 to 3.389 ..so basically 3.000 inch by 16.600 inches long

the Peak TQ was maybe a little less than it should
for what the Peak HP was ?? probably due to combination of
Total Induction Length=>specifically the Manifold Runner length even
though it was lengthened and due also maybe to Collector length
not being around 16.6 ".

However, take a look at the Intake Bowls...no signs of exhaust reversion
...they look like the ones on my site .

Also all the NHRA various size and Brands of SuperStock Engines
i've been involved with will use all of their FlowBench CFM
converted into HP or at least very close.
as well as most high-end Bracket Engines and Comp Engines

but on BES engine it did not use all the Flow CFM of Heads
that could have been due to "Stalling" in conjunction with type of Cam
being a solid lifter vs solid roller, and the 6500 RPM limit .
At 6500 his Power Curve looks like its still going to climb higher.

Here's a pull down of an earlier engine, you can see bushed down mains, something I have mentioned before.

http://www.jonkaaseracingengines.com...-emc-2003.html

The engine at the top of the page in that link, the winner of the 2009 challenge which is very close in size to our strokers, it made just under 700 hp at 6,500 rpm. Again not emissions friendly and in reality while they run on pump fuel you would want to knock a point or so off the compression ratio.

These engines interest me because they are two valve and they show how they are built, nothing like lessons from the experts There is regular winners in the Engine Masters, they know their stuff.

Greg

tv

thought these might be fun and helpful, I know you look at all different makes and builders, these guys seem to know a thing or 2 and have an interesting intake, I like the sound

http://www.youtube.com/watch?v=y-Ut65O-knk


http://www.youtube.com/watch?v=-B1Vkffye38&NR=1