Discuss:

 

Randy rmf(r.i.p.) built a pair of headers like that. Search and you might find the thread.

 

Uh

 

Randy did for this head. He used it as collateral for a loan; the "bank" has it now

 

Any more info as to theory? Results? Etc?

 

What motor is that header for. What was the goal.

I'll share what Randy told me later.

 

could be harmonic/wave tuning for 1 runner per valve...

it might be "stronger" as far as the signal is talked about...

vs having a measurement from the back of the valve to the tip of the velocity stack
only to have the last inch of the port bfor the back of the valve.. have a divider going into two valves

me thinks... (ive known to be wrong... most of the time LOL)

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on to the first pic by the OP... could be its a better way of making the effective scavenge, work better for more power?
by looking at the per valve pairing?

 

It's Jon Kaase's header for a 400ci Ford 4 valve mod motor. They are legal in the EMC (dyno competition) this year, and historically the biggest valve area to bore ratios have been winning. Obviously, the Fords are kicking everyone's asses.

The engines have an RPM limit of about 7000 RPM, and points are scored for overall power with respect to displacement. The exhaust side is hyper critical since the lower RPM is so important, but right now Accufabs Ford is in 1st with a standard 421 design.

I was originally expecting that the exhaust port might be divided, but other people much much smarter than me have said its not likely as having the divide in the port may act like an X pipe and balance pressures and harmonics. Others think there is something to giving each valve its own runner and even making the cam timing between the two different...

 

My perspective on that design is probably to target a broader rpm range. The 2 primaries per runner allows it to support the flow demand at the higher RPMs and the primary size and long length are what produces the midrange power. I can see it working/possibly working given the engine displacement being used.

That design is along the lines of the dual runner IM setup and even the variable valve timing stuff, this time its just in the header.

I have a very close friend that worked alongside Dave at PD that competed in that EMC competition as well, good stuff.

 

EG1834

im almost sure there is a divider in the port extending to the flange..
because that port size on the flange is awfully wide for an exhaust

its like the intake of a DSM intake (4g63)

my best guess is that, tuning each exh. primary (per valve) u can pair it so many ways sequencially.. to help pull a 1-2-3 sequence

+ possibly staggering the LC too.. kinda like Colt Cam's "tri flow" aproach

 

If it is working for Kaase, that's great.

400ci is big, and the header pipes don't look that big.

Randy made an 8-pipe header for the head pictured. He said it was choked up top, but the bottom-end was improved. He believed that it had too much surface are (and resultant drag), that hindered top-end.

 

Well these are only 7000RPM engines and overall power is what scores the points. He picked up some major points today and may have taken the lead.

 

How is overall HP measured. We talking about HP averaged from 3-7k?

 

2500-7000RPM I believe. Not 100% sure how they come up with the points system exactly. I just know the overall power and the cubic inches are the determining variables.

 

Looks like a DTS engine dyno is used there. If I remember correctly, it only does a 3,000 or 4,000 rpm sweep.

 

Yep, I stand corrected. 3k-7k. Here is the scoring info BTW

"SCORING

Performance rankings for the competition pulls will be computed using
SUPERFLOW/DTS software. Flywheel diameter & thickness will be used as part of
SUPDRFLOW/DTS programming to arrive at the inertia factor. Bore/stroke figures
will be used as part of SUPERFLOW/DTS programming to arrive at the frictional
losses. The upper RPM limit will be set at 7200 rpm. Each entry’s scoring is a direct
result of a Team’s engine Dyno performance, and resulting scores are specific to the
engine. Points and scores are not transferable from a Team’s engine to another
engine entry by the same Team, nor are points and scores transferable from one
Team to another Team.

If an event is postponed for any reason prior to the start of the scheduled run,
it is necessary that any engine and Team still eligible for event competition be in
attendance at the rescheduled date and time to be eligible for all scores and any
contingency monies and/or awards. If an event is postponed and/or disrupted and
rescheduled due to weather or other conditions, natural disasters, acts of God, etc.,
participants unable to return will not be eligible for any final placement and/or
contingency monies, and will be listed as Did Not Finish (DNF) in the Event
competition postings.

Scored qualifying pulls will consist of three fast acceleration pulls starting at
3000 rpm and ending at 7000 rpm. Then, "average torque corrected to SAE specs"
(recorded to one decimal place) from each of the three scored qualifying pulls will be
added together and divided by three (the resulting average of corrected torque will
be recorded to one decimal place). The "average horsepower corrected to SAE
specs" (recorded to one decimal place) from the three scored qualifying pulls will be
added together and divided by three (the resulting average of corrected horsepower
will be recorded to one decimal place).

To compensate for the varied engine displacements, the corrected average torque
and corrected average horsepower from the three scored qualifying pulls shall be
added together then multiplied by 1000 and divided by the CLAIMED cubic inch
displacement of the engine. Corrected torque, corrected horsepower, & final quotient
numbers are recorded to one decimal place.

Example:

C. Torque #1 C. Torque #2 C. Torque #3

427.4 425.5 424.8 Avg C .torque = 425.9

C. HP #1 C. HP #2 C. HP #3

365.6 364.3 363.8 Avg C. HP = 364.6

(425.9+364.6)*1000/354 Quotient = 2233.0

Rounding of numbers will be utilizing standard rounding:

Example 2232.96 = 2233.0

Claiming a cubic inch less than actual calculated cubic inch as stated in the
ENGINE-displacement section of these rules, shall result in disqualification. Claiming
a cubic inch 5 or more cubic inches greater than actual calculations shall result in
disqualification."

http://image.automotive.com/f/445691...ch-26-2013.pdf

 

Kaase's Ford scored something like 2960 points BTW.

 

How many teams are using 2-valve and how man 4-valve?

 

Three teams with 4v engines, all three in top three spots. Valve area to bore ratio dominates every year, so it was a no brainer, but not everyone competing could afford to build those engines.

 

4-v must be the ticket. Multi-valves allow for staggered cam profiles which can be tweaked for an rpm range better--2 lobes two tweak (duration, lift, lobe center) instead of one. I found this to be the case from our experience with staggered v. non-staggered primaries on BVTEC cams.

 

Randy told me the only thing he liked about that design is that it looked cool hanging on his wall lol.

 

I'm sure that does make a difference. The valve area is the main thing, that's for sure. I'll be waiting on the issue of Engine Masters that will cover the tear down of the engine to see what was in it.

The crank alone was a custom fully counterweighted billet piece from Sonny Bryant I believe. We are talking $3500 and 12 weeks to get just the crank! Over 4.5" of stroke on all those bad boys to meet me 400ci minimum!

 

just to continue this.. and maybe head to a nicer "technical" discussion....

how bout this





renault sport f4RS fsr engine off the clio's
used in the formula renault series...

some things here goes quite against the "norm"

wonder wat people think