Guys.  Had a great time at the Engine Masters Challenge and would definitely do it again.  I entered a 375 inch Y which ended up being too big an engine for the iron heads to have a really good score.  At 6700 rpms, the engine was just out of air.  Good peak numbers though and that’s what I was counting on.  The 316 incher I readied for last years competition would have had a much better score at the expense of reduced peak numbers.  The big numbers did not rule at this competition as there were several 800 plus horsepower engines but their average scores were down compared to the smaller engines.  Triple thanks goes to the other Y team members who assisted me at the EMC site which included Jody Orsag, Harry Hutten, Jerry Christenson, and Royce Brechler.

The 375 got that way by way of a 3.859” bore with a 4.00” stroke.  Pistons with a 9cc dish gave me a 10.1:1 static compression ratio and 9.0:1 dynamic compression ratio.  And the engine idled like a champ with a healthy rumble at 900 rpms through the mufflers.  The original plan was to enter the 4.00” bore X 4.00” stroke combination (403 CID) but the block just ended up not being strong enough once the cylinders were bored out and replaced with sleeves.  That engine ultimately twisted the block on a moderate dyno pull to the point the camshaft was difficult to remove.  A new set of pistons arrived in the middle of September for the 375” combination at which point the assembly of a new and smaller sized Y started going back together.

On my dyno, the 375 incher was peaking 462-464HP and 446-449 lbs/ft torque.  At the EMC competition, I lost numbers like the other competitors.  The best EMC numbers after tuning changes in preparation for the qualifying session netted the Y team 433HP and 416 lbs/ft torque peak values.  Still not too shabby for an engine We could have put back in a car (or truck) and driven back home on pump gas.  Although I tested the engine at 7000 rpms on my end, it was pushed to 7400-7500 rpms during the competition.  It held up just fine to the surprise of everyone at the competition.  After 49 pulls on my own dyno, I was reasonably confident that the engine was not going to be easy to hurt.  I had already increased the over the nose valve spring pressure from 330 lbs to 388 lbs during the course of testing just to insure that the rpm capability was going to be there.  The Isky cam and lifters are showing no signs of wear after all of this abuse.

The electric water pump is an Ebay big block scrub electric pump that I gutted and then made an aluminum plate to adapt it to the Y engine.  Although I had reservations about using it in the competition due to some air lock issues that were cropping up, it worked just fine in the competition.  In fact, the engine temperatures with each qualifying pull were consecutively dropping and the last pull was at 136°F which was in itself a performance deterrent.  When I build a new version of the electric pump, I do have a plan on how to make the pump self priming and eliminate the air block issue.

And that’s the short story of what happened at the Engine Masters Challenge.

Paul, now you know how the 375 inch motor came to be.

Great job and vindication for all of us Y-blockers.  Y's are definitely running with the Big Dogs now.

If the competition rules stay the same for next year and the Aluminum heads do not materialize or (what I would like to see) the rules change to require OEM iron heads would you go for a smaller engine?  If I remember past EMC results there were engines as small as 288 CID.  I can't estimate how much extra would be gained in specific output but if going from 375 to 300 cid would result in a 10% increase,  you could be looking at about 400hp on your dyno.

Besides the iron heads, the Y seemed to have the least exotic induction system of any others I saw pictured on the EMC web site.  Are you thinking of any improvements on that side?

Let the hot stove discussions continue.

What a great team and a great accomplishment - JJ

The rules this year allowed engines as small as 280 cubic inches.  That got a 4.6 Ford Mod motor into the show.

Regardless if the heads are iron or aluminum, the smaller cubic inch Y engine would have been more favorable under this years rules format.  I know that now but in hindsite would not have known before actually testing this combination.  Better flowing aluminum heads will obviously support a larger engine though.  There’s no doubt in my mind that last years 316 engine with this years iron heads would have produced a much better score this year while potentially still coming close to the 400HP barrier with a pump gas combination.  At the EMC competition, it’s all about the score and not the peak values.

This years rules format specified a cast intake manifold without external modifications and the Mummert intake was definitely the best available.  A big Thank You goes out to John Mummert in getting me some of the new intakes to work with for this competition.  The next best intake design on the list was the Blue Thunder.  Most of the 3X2 and 2X4 intakes as originally cast are not the big power producers for this kind of competition and especially if limited to the carb bolt patterns that came on them.  If a good single plane design had been available, then that may have helped the overall score.  Testing is really the only way to know for sure on any of this.  This particular engine saw seven different intake manifolds on it during testing along with a variety of carb spacers and carburetors.  But an injection intake with Webers would be worth looking at based on the performance of the early Hemi that was running that combination this year.

The 375 incher did surprise me in testing when I tried a 1050 Holley Dominator on the Mummert intake and it made even better numbers.  Made three pulls with the Dominator and as I leaned the mixtures, the power levels just kept climbing.  Started out with 88 jets square and was down to 81 jets square by the third pull with the indicators still pointing to the engine being on the rich side with 81 jets.  And the Dominator idled just fine and cleanly with all the jet combinations.  Unfortunately I was already in a time crunch situation at that point and didn’t have the aluminum stock available to whittle out a spacer/adapter that would fit the rules.  For the test, I used a 2” adapter I had on hand just to try the Dominator carb and that particular adapter was just too tall as required by the rules.

Uncrating the engine and the crowd is in awe.  "What is it?"

The Y rubbing elbows with the big guy.

   Aluminum heads are only better in one area, given the same ports and valves. They're lighter. Also, it's generally accepted that they are easier to repair. If they are dimensionally identicle to an iron head they'll actually produce a bit LESS horsepower! The aluminum. head transfers heat from the combustion chamber too quickly. Most aluminum heads are equipped with better ports and valves than the OE iron ones. The material around the combustion chamber is thicker to slow heat transfer rates and typically they'll have a smaller combustion chamber for more compression. It's common for an aluminum head to carry a point more CR and be able to use the same octane fuel  with out pre-ignition. Improving a stock 50 year old head shouldn't be a major problem, after all it wasn't designed to carry the amount of air we look for today. However, it turns out to be somewhat more difficult than you'd think. Ford did a pretty fair job on them, then completely blew the SBF 260/289 heads.

The Y design in all probability has a lot of swirl but the more modern heart shaped combusion chamber should add some performance.

Don,

        Absolutely, Mummert's aluminum head has a significantly different chamber from the Y-block heads. Of course they're not all the same either. Just looking at them with an uneducated eye, the 113's look to me to be the best. But i don't have a set of G's to compare. Be interesting to see a back to back between 471's 113's and G's on a dyno. The compression differences would definitely favor the G's But I wouldn't be surprised to find the 471 & 113 flowed as well. Shrouding of the valves by the chamber walls has a major effect of flow into the cylinder. That's one of the reasons big valves often show no real improvement.

.

    824 cfm!!? I thought Y's didn't like big carbs!!

Don't forget how important the exhaust port is. The most surprising engine I ever dyno'ed had the small letter ECZ-G heads, which in my opinion have the best exhaust port of any Y-Block head. The most disappointing engine had some heads that someone had hogged out the exhaust ports in all the wrong places.

Unfortunately that engine was the only one I've ever tested with the small letter Dearborn ECZ-G heads. No back-up to confirm the heads were the real difference.

With regards to heat disappation, an aluminum head has a lot less water in it to help reduce the amount of heat that is carried away. I studied alot of aftermarket alum heads to try to get an idea of how much to leave out. The stock Y heads have water all the way to the intake gasket surface. Aluminum heads have just enough to cool the exhaust ports, valve guides and combustion chamber.

Crash test aluminum head is in the CNC machine and spent last weekend and Monday on program. Might not have much chance to work on it again before Friday. Hope to have it pretty well complete by Sunday PM.

The Engine Masters magazine itself will be out in early spring at the stores.  The EMC magazine is only published quarterly so there is no subscription available for it, newstand availability only for that one.