Bill.  Thanks for sharing the pics of the 2X4 Cain intake.  Makes me wonder what other neat parts do you Aussies have squirreled away?  Looks like Mr. Cain was quite a busy guy in casting up some of those different manifolds.

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John.  I do not have an air hat to monitor air flow at the carb.

 

I’m finding that the dip in the torque curve is very pronounced when using short tube headers.  The dyno curves posted by Pete was with the short tube headers in place which is what was used at the time for the comparison of the two manifolds..  I do have data on the same engine with longer tube headers and the Blue Thunder intake and the dip in the torque curve improved significantly.  But the Cain manifold was not tested with the same longer tube headers so any comparison of intake manifolds being tested with different headers on that particular engine was considered invalid.

 

Right now I’m in the process of amassing a serious collection of headers which will be tested on a mild 322 inch Y in the near future.  The Y does appears to be more critical in header design than some of the other mainstream engines but suspect what I’m really seeing is what the extremes are when varying the header tubing sizes and lengths as well as collector sizing on the same engine.  Most other engines usually have much better header designs available for them so some of the less than desirable designs really do not get tested on them.

Lorena, Texas (South of Waco)

Ted, I notice that the B-T intake graph shows a very distinct drop in torque between 4400 and 5000 rpm. This seems to be very common on the Y-Blocks I've tested also but I have no idea what causes it. I've often seen it during testing, usually between 4500 and 4800. Your graph is more pronounced than usual. That is a good area to concentrate on with headers, spacers ect. You can really help your score if you can flatten that out.

I'll see if I can find some pics of the modified Ford intake.

John

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

Regarding modifying the ECZ9425B: I modified quite a few with 2 slots instead of 4 holes before the B-T became available. They ran very well and we made a maximum 360hp with one. Lindsay Shoemark (down in OZ) has that particular manifold. We dyno'ed it on 2 engines, a pretty hot 314cu in (360hp)and a milder 332cu in and it moved 510CFM on both. The 332cu in with 9.5:1 compression and 224@ .050" cam made 339hp. When the B-T became available we dyno'ed a 331cu in with 9.5:1 compression and a 224 @ .050" cam and it made 329HP.

A stock Ford intake on the 314 passed a total of 461CFM and peaked @ 314HP

On Ernie Phillip's first engine we used a heavily modified ECZ9425B and it made 424hp. I still have that manifold. It still has the divider in the plenum.

I strongly believe that too much plenum area will cause problems, particularly at low RPM. The opposite extreme is to leave the 4 hole opening and use one of the 2" 4hole spacers. They seem to kill top end.

We did find that the Ford manifold liked a 1" open spacer with the divider left in the manifold because of a lack of plenum.

Ted, do you have an air hat to monitor air flow into the carb?

John.

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

Ted, pete and rest of you guys, i thought you may be interested in seeing another old Cain intake, its 2 x 4 open plenum and these were only scource or option here to have holley style 4 bbl carbs on our yblocks other than scarce truck cast B intake. Regards aussiebill.





  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Pete.  The BT intake used in the testing with the Cain manifold was a version two manifold.  Although removing the divider in the intakes hasn’t been tested on the dyno, the divider scenario was tested at the dragstrip a good while back with two BT intakes.  One intake had the divider removed and the other didn’t.  Both ran exactly the same ets but were completely different in where the power was being made.  The intake with the removed divider was stronger on the topend while the manifold with the divider still in place was stronger at the very bottom (60’ times).  Conclusion was that removing the divider hurt the bottomend torque in that particular instance but topend performance was improved.

 

But with that in mind, I am building a spacer for the Cain intake that will allow testing of that particular intake with a divider in place.  This will make the intake somewhat similar to the Offenhauser 360° intakes that were available for awhile for other engines.  There just seems to be no end to the number of scenarios that can be tested at this point in time.

Lorena, Texas (South of Waco)

hhmm 99, thats a sizeable gap, and I believe that was with a standard BT, not the newer mk2 version which should be even better. No doubt someone has modified a BT by removing the centre divider to make a large open phleum [more so with a spacer], this would presumably open the gap with the Cain even more.  This leads to the cast factory 4 barrel, any one done the same to it? Any advantage in converting the 4 holes to the BT set-up of 2 larger "slots". A spacer looks to be mandatary with any set -up.

Pete, one of the Aussie mob. Beechworth, Victoria60 F100 Panel Van, Y-block. 65 Galaxie Country Sedan 390

Using the scoring methodology that’s used in the EMC competition, the scores for the two intakes as tested looks like this:

Cain = 1672 points

Blue Thunder = 1771 points

Lorena, Texas (South of Waco)

Pete.  Since running the Cain manifold, I’ve been testing some of the various header designs that have been sent to me and finding significant gains in that area.  I’ll be retesting the Cain manifold again on the mule engine with longer tube headers as that may help to bring up the lowend torque values.  But like Paul says, it has a long way to go to catch up to the Blue Thunder intake.  Still, the Cain manifold worked much better than I anticipated in that it wasn’t as lazy in throttle response that I thought it would be and appeared to take the fuel without much issue.  When I get a chance, I'll calculate a score to give a better idea of how the two manifolds compare.

Lorena, Texas (South of Waco)

Pete, while I have no idea what tuning adjustments Ted has up his sleeve, unfortunately I doubt that anything can be done to make the Cain intake competitive. If you study past EMC stats, you will notice that because of the combined scoring system, roll in Torque is paramount. All of the top half dozen or so engines in the last test, had torque outputs exceeding there displacements at the starting RPM. The Cain is down about 28 lb. ft. behind the Blue Thunder, at 3300 RPM & it didn't meet that criteria.

Paul

Received some snail mail from Ted the other day [thanks Ted] which included the reports for the first dyno pulls comparing my Cain inlet manifold with a Blue Thunder. As expected the Cain was down on torque but I was disappointed it didn't top the BT in the higher rpm area, maybe in the last 1000 to 7000 EMC limit might be the difference. Different engine, different tune things might be better.   Score:  BT 1  Cain  0

Pete, one of the Aussie mob. Beechworth, Victoria60 F100 Panel Van, Y-block. 65 Galaxie Country Sedan 390