Published by tedeaton on 24 Mar 2010 at 06:58 am
The 2009 EMC competition is now history. The Y engine that was taken to the competition was the 375 inch version that was far from being a reality when September 1st rolled around. The 4” crank and 6.750” long rods from the previously wounded 4″X4″ Y engine were used in the 375 incher along with the cam and lifters. Diamond Pistons came through with a set of custom pistons to fill a 3.859” bore and a pair of Total Seal 1.2mm rings with a 3.0mm oil ring sealed each piston to its respective bore. This engine had good peak numbers on the dyno but the overall score was down due to the oem iron heads being a serious bottle neck in the higher rpms. Just too much cubic inch for these heads. Now I know.
With the 375” engine assembled by September 19th, it was put on the dyno and some serious testing commenced. Seven different intake manifolds were tested along with a variety of carburetors, carb spacers and rocker arms. Also tested was a pair of headers with one set being off of my ‘23T altered roadster and the other being a set of stepped headers supplied by Jerry Christenson and Royce Brechler. The final engine combination used the new Mummert intake manifold with a Holley 950HP (834 cfm actual) and the stepped headers with 1.75/1.875” tubes feeding into a modified 3½” collector and then the mufflers. Metal Finishing Services (Church Brothers) provided the Jet Hot coating for the headers. An electric water pump design was also finalized and used. By the time the testing was completed, the dyno was showing 462-464HP and 446-449s/ft torque peak values through the mufflers for the combination that was being taken to the competition. Not too shabby for a 10.1:1 compression ratio and on pump gas. Of special note is a 1050 cfm Holley Dominator carb was tried and to my surprise, the torque values jumped up significantly. There just wasn’t enough time in that last week of thrashing to build a rules specific carb spacer/adapter to work out that particular combination but the engine definitely likes more carb than what I was taking.
With all the testing behind me, the engine was crated and made ready for shipment. By luck of the draw, the Y would make its qualifying pulls early on Thursday October 8th which meant I could take it to the competiton myself rather than have it shipped in advance. As a result, I get the engine to the EMC site (University of Northwestern Ohio) in Lima, Ohio on Tuesday by noon. It was required to be there by no later than 5PM or it would not be eligible to run. On Wednesday, the engine was installed on a docking cart and is hooked up to the dyno later that evening in preparation of being the first up the following morning in that particular dyno cell. Thursday morning the engine hookups are finalized and the engine is ready to start and run for a timing and carb check. I’ll add at this point that the crew members for this adventure also included Jody Orsag, Harry Hutten, Jerry Christenson, and Royce Brechler. The Y was indeed being very well represented and was the perfect crew for the occaision.
There were some issues with the carburetor fuel line prior to startup on Thursday morning and the spare I had brought along was installed. That could have been a show stopper but someone upstairs was looking out for us. Once that was resolved, the engine fired right up and idled cleanly at 900 rpms. Timing is checked at 3500 rpms and is sitting at 39° total. Perfect! After the prerequisite five minute warmup period where both the oil and water temperatures are brought to 160°F, the engine then makes three back to back warm up pulls from 3000 to 7000 rpms. At that point the engine is shut off and the team has five minutes to decide on what tuning changes can be made in the allotted twenty minute tuneup period. Prior to installing the carb on the engine the previous day, We had rejetted the carb up to 77/89 jets whereas it had been 75/87 jets on its last dyno pull in Texas. Looking at the data from the warmup pulls, the Y team decides the engine would like more jetting. The plan was to simply change the jets, make a short pull, re-evaluate the data, and make another jet change if necessary in the allotted twenty minute tuneup period. Didn’t quite work out that way. The bowls were pulled and the jets were changed out but upon repressurizing the fuel system, the rear float wasn’t holding the fuel and fuel poured out of the rear carb vent into the engine. The bowl was pulled again, float moved around and reinstalled. Same problem and more fuel into the engine. Team members go to both sides of the engine and start pulling all the spark plugs while I pull the rear bowl once more but this time I remove the needle seat assembly from the bowl and blow it out. I reinstall the bowl assembly back on the carb with the float level eyeballed in place and this time it holds the fuel when pressure is applied. At this point, the engine is spun over with the plugs out and there’s a bunch of fuel coming out of cylinders on each bank. As soon as the fuel is cleared from the cylinders, the spark plugs go back in and the plug wires are hooked back up. There’s no time to double check the rear float level so I instruct the dyno operator to start the engine, make a cleanout rev on the engine and then a 3000 to 4500 rpm dyno pull. This is done and upon shutting down the engine, there are only 90 seconds remaining in our tuneup period. The pressure was definitely on for a bit but all is looking better now. A quick look at the short pull data shows an increase in power so it looks like a good call on the jet change. It’s a good thing as We are now officially out of time.
At the end of the twenty minute tuneup session, the engine is restarted, allowed to warm back up, and then go into three more back to back 3000 to 7000 rpm pulls. These are the qualifying pulls and the ones that count. Jerry calls them the money pulls. Did I forget to mention that the dyno permits the engines to over-rev to 7400-7500 rpms on each pull? I wasn’t really excited about that but the team members as well as the spectators were starting to cringe. I had already increased the over the nose valve spring pressure from 330 lbs to 388 lbs during the course of my own testing to insure that the rpm capability would not be compromised. The engine makes the three required back to back pulls and I then give the dyno operator instructions on how to shut it down. A quick look at the data shows that the jet change was still a good call as the engine is now peaking at 433 horsepower and 416 torque. At this point, I’m taken to a side room where the score is tabulated and I sign off on a 1949.8 score. Yes!!! We’re ahead of a 426 Hemi with dual quads and two other engines that couldn’t complete their qualifying runs. Mission accomplished. We’re not in last place and as Jerry says “Just a few spots out of first”.
The rest of the day is spent watching the remaining competitors run their engines. The top six from the four days of running will run again on Friday for the money. Jon Kaase ultimately wins the competition on Friday with the 403 cid Ford engine he won it with last year and his other engine (a 511 cubic inch Boss engine) comes in sixth. Second place comes in 1.4 points behind first so it was a close race for first. A mid Fifties Hemi (360 CID) comes in third place overall and was indeed impressive with its rows of Weber carbs doing their job.
Of special note is all the competitors were getting lower numbers at the competition than seen on their own dynos. Some of the competitors were commenting that they were down at this event by over 100 horsepower. Our Y entry ended up being over 30 HP down from what I was seeing at my shop. Not a major concern as everyone is in the same boat on this one but this did create some speculation as to why the differences. A possible consideration and falling into the equation is that it essentially rained each day of the competition. Although the air was cooler, it was definitely saturated with moisture.
The engine oil and fuel was provided at the competition. I had already tested and tuned the engine at the shop with the sample of 91 octane fuel that had been sent to me. The oil used during my own testing was Valvoline 20W-50 racing oil. At the competition, Valvoline was not on the selection list so I used Lucas 20W-50 full synthetic racing oil along with some Lucas zinc additive that was available. It was interesting that the oil pressure was about 10 lbs less with the full synthetic than with the Valvoline although both were the same rated viscosities. At this point the oil pressure difference could reside in either the oil itself, a difference in sensor readings between the two dynos, or the oil temperature. There will be more testing later to determine exactly what is going on in this regard.
In looking at the other engines in the competition, the Y entry was the only engine present with oem iron heads. All other competitors were using some form of aftermarket aluminum head. Roller camshafts were also very prevalent and if the Y wasn’t the only one with a flat tappet camshaft, then it was difinitely in the minority. When the Popular Hot Rodding and Engine Masters Magazine articles hits the newstands starting in January, more details on the competitors engines will be available.
On Friday, We recrate and load the engine and the second crate of parts back into the truck and prepare for the trip home. After the awards ceremony later in the afternoon, Jody and I jump into the truck and start putting some miles between us and Lima, Ohio. Harry, Royce, and Jerry have already headed home long before this. And of course it’s still raining. After spending the night in Southern Illinois, We use up Saturday travelling back to Texas and get home after the sun has set. All in all, a very good trip. Special thanks again to all that helped make this happen!!
Originally published in the Y-Block Magazine, Nov-Dec 2009, Issue #95.