Wilpower (Wildcat) Vs. Huffaker Intake

[Greg55_99]

This is excellent info from Dan Jones

Spent a little time evaluating a couple of Rover V8 single plane intake
manifolds on Dave McLain's flow bench in Cuba, Missouri. I wanted to
know which of the intakes would flow best when bolted to my 1964 Buick
300 aluminum heads. The heads are ported and use larger Stage 1 Buick
V6 intake and exhaust valves (1.775" head diameter for the intake and
1.5" for the exhaust):

http://www.bacomatic.org/gallery/album1 ... ambers_001

http://www.bacomatic.org/gallery/album1 ... take_ports


http://www.bacomatic.org/gallery/album1 ... ust_ports2

The two intakes tested were a Huffaker:

http://www.bacomatic.org/gallery/album13/Huffaker_front
http://www.bacomatic.org/gallery/album13/Huffaker_side

and a Willpower:

http://www.bacomatic.org/gallery/album13/Willpower_1
http://www.bacomatic.org/gallery/album13/Willpower_2

Note the Willpower intake pictured is not the actual intake tested. I've
not yet taken pitures of the intake we tested but it differs from the one
pictured in that it has EFI injectors bungs in each port but the injectors
were not installed for these tests. The Huffaker has larger ports which
better match the Buick 300 heads:

http://www.bacomatic.org/gallery/album1 ... aker_ports

The Willpower has smaller Rover-sized ports but has a better radius on
the end runners than the Huffaker. An end port and a center port of the
head were first flowed without an intake attached to get a baseline, then
flowed with the intake bolted in place. Also, a Holley 780 carb body
with the throttle plates at full open was bolted to the intake to
represent the pressure drop across a carb or fuel injection throttle body.
I'll be using an EFI throttle body later but have not purchased it yet.
When the heads were ported, they were tested on a Superflow bench at a
28" H2O pressure drop. The head had a clayed intake radius but no exhaust
pipe stub was used on the exhaust. Those numbers are shown in the 2nd and
3rd columns. The 4th and 5th columns are the same head flowed on Dave's
bench which has a 10" H2O pressure drop. The numbers were converted
mathematically to 28" to be on a consistent basis. Note the numbers are
somewhat lower than those of the 28" bench. We're not sure if this due
in part to the conversion or is simply bench-to-bench variation. In any
case, it doesn't influence the results of the intake manifold tests.
On both single plane intakes, the center runners are short and straight
while the end runners are long and curved, so one center port and one end
port were tested. The Huffaker was bolted to the head and tested first,
followed by the Willpower. The results are shown below and are best
viewed in a non-proportional font like courier:

Valve Buick 300 Ported Buick 300 Same head with Same head with
Lift 1964 head on McLain's Huffaker intake Willpower intake
(inch) aluminum flow bench center runner center runner
ported 10" numbers
Int Exh converted to 28" CFM % of CFM % of
1.775" 1.5" Int Exh bare bare
1.775" 1.5" head head
Int Exh
center
port

0.050 -- -- 26.3 22.6 26.1 99.2 27.6 104.9
0.100 66 47 56.3 51.6 55.1 97.9 56.4 100.2
0.150 99 82 86.8 75.0 87.8 101.1 89.0 102.5
0.200 129 104 115.1 98.4 117.2 101.8 119.1 103.5
0.250 155 119 140.4 114.1 141.4 100.7 142.8 101.7
0.300 174 130 158.1 125.4 160.6 101.5 160.0 101.2
0.350 187 139 171.7 134.4 169.9 98.9 167.9 98.0
0.400 191 146 179.8 140.2 170.5 94.8 172.2 95.8
0.450 194 150 181.3 143.2 172.6 95.2 174.3 96.1
0.500 196 152 182.1 144.3 173.9 95.5 175.3 96.2

Valve Buick 300 Ported Buick 300 Same head with Same head with
Lift 1964 head on McLain's Huffaker intake Willpower intake
(inch) aluminum flow bench end runner end runner
ported 10" numbers
Int Exh converted to 28" CFM % of CFM % of
1.775" 1.5" 1.775" 1.5" bare bare
end head head
port

0.050 -- -- 25.5 22.6 26.8 105.9 26.9 105.5
0.100 66 47 55.0 51.6 56.6 102.9 55.4 100.7
0.150 99 82 87.0 75.0 88.2 101.4 88.6 101.8
0.200 129 104 116.9 98.4 114.1 97.6 119.8 102.5
0.250 155 119 143.4 114.1 132.5 92.4 144.6 100.8
0.300 174 130 157.8 125.4 146.5 92.8 164.8 104.4
0.350 187 139 171.6 134.4 155.6 90.7 173.3 101.0
0.400 191 146 178.3 140.2 156.9 88.0 175.0 98.1
0.450 194 150 180.8 143.2 156.6 86.6 176.0 97.3
0.500 196 152 182.9 144.3 157.6 86.2 175.3 95.8

Despite the smaller runners, the Willpower is the better flowing manifold.
The center ports on both intakes are quite close to the head flow but
the Huffaker end ports are not as good. I think it would be worthwhile to
port just the ends of the Huffaker intake end runners with a better radius
to see if the flow loss could be recovered. There's a slight drop off in
flow as lift increases on the Willpower intake that may be due to the small
port size. The Willpower could be ported to a larger size but given how
close the intake is to the bare head flow, it's probably not worth the
trouble. The worst flows are at 96%. As a point of comparison, we've
recently flow tested a couple of (non-Rover) dual plane intake manifolds
and they were in the mid seventy % flow range (unported).

The exhaust-to-intake flow ratio on these heads is excellent. Dave thought
a bit larger itake valve, at the expense of exhaust valve size, might make
more power if it were practical. During our tests, a 4" diameter tube was
used to simulate the effects of the cylinder wall. To see if shrouding
might be a problem, the tube was moved around (closer to the valve) but
little effect was noted.

Dan Jones

[HairbearTE]

Hi Gregg, as you know i'm building a similar spec engine myself with the Buick 300/wildcat/4bbl throttle body combo. The figures posted are of great interest for me. I realised very early on that the ports on the Buick heads were quite a bit bigger than those of the Wildcat (willpower) inlet. Given that my engine is based around a short stroke and medium capacity (its 77mmx94.5mm) I felt that no serious work was needed on the inlet and concentrated my efforts on a basic clean up of the casting and a litle work with the dividers in the plenum area. With regard to port matching I am focusing on maintaining a constant port floor throughout the entire inlet/head assembley. I intend to leave a small uniform step around the port walls and roof where the smaller manifold port meets the larger head port. The theory is of course that this will have a positive effect by reducing the wave signal interaction in the single plenum area of the inlet manifold. My work on the heads is focused towards the area behind the valve (i'm running slightly smaller 1.7" Ti valves that should suit my capacity of 4.3 well enough) and the 'long' port wall. I have not increased the inlet port opening size at all (exept to match all port sizes). I have also put a lot into the design of the guides themsevles in order to reduce as much as possible the flow restriction caused by them without actually just shaving them off where they enter the port or leaving the guide dangerously thin. I've taken moulds of the Wildcat Inlet using a product called vinamold and have also taken molds of the inlet tracts in the heads themselves so that i can replicate the entire inlet tract as a whole in plaster. This allows me to test my designs and hopefully reach the maximum flow/minimum cross section/max velocity design that I am looking for. Actual flow testing is on hold for a while since i managed to slip from "fixing a small leak" in the 'shop to "rebuilding and rewiring the whole place and everything in it" and my newly completed flow bench got dismantled and integrated with the new layout only shortly after I was able to switch it on! I'm using an .020" over 3.9 liner for testing in order to accurately recreate the conditions within my own engine as best I can but I also have a stock 3.9 liner from which to build a test cylinder and an acrylic tube that I can open up to 96mm to test heads for the big bore top hat rovers. I've also got a few different carb spacers that i'll be testing with my own combo to asses their value in my application. Thankyou for posting your findings here, I shall study them with interest and of course post any interesting findings I make myself as soon as they're available.

[Wotland]

Hello, back on the forum after an long absence.
Very interesting info Greg.
Also I am building similar Buick 300 heads with Buick V6 Valves.
The inlet port size has been untouched but exhaust ports have been D-shaped.

Chambers have been shaped with boss knife edged. The original boss was trapeze design.


HairbearTE, do you have some pictures of valve guide area you have modified ?

Thank

[HairbearTE]

Hi wotland, good to see you back. I dont have any pics of the guides but I'll take some and post them here when I get a chance. I havent actually finished them yet because they are not in the heads but i've had them turned down in the manner similar to the shape of the back of a valve. The guides I have are manganese bronze alloy and came with the valves that i've got, the thing is they are larger in diameter than standard rover items (something to do with dispersing the heat and using Ti valves) and as such would've created an enormous blockage in the port if I left them alone. I was going to shave them down in the manner of the bullet guides you can buy from the likes of RS etc but I realised that their size was such that this would still not be ideal, I've seen guides blended perfectly into the heads in some race engines and if you've seen that kind of installation you'll know what I mean. I've removed some material from the guides now while they're out of the head because its much easier to do so but I have left enough to blend in once they are installed.

[Rev_erend]

When I was up at Wildcat the other week - I'm pretty sure Ian said he was developing some new carb manifolds..

Give him a call.

[rover hot rod]

Has anyone seen this design

[chodjinn]

Has anyone seen this design

This is the longest zombie thread bump I have ever seen.

Mate, this thread is EIGHT years old.

[rover hot rod]

Well I am new to this website. And I have no idea where else to post it.

[sidecar]

Well I am new to this website. And I have no idea where else to post it.

Welcome to the V8 forum!

If you have something interesting to post then you can if you wish just post it up as a new post.

[rover hot rod]

COOL thank you for that