OUTLAW CYLINDER HEADS
by Mullins Race Engines

   
     

Mullins Race Engines will now be offering a new product called OUTLAW CYLINDER HEADS. These cylinder heads are exclusively made by Mullins Race Engines. Our goal is to offer the most powerful 23 degree cylinder head available today! It will be developed, all machining done in-house (including 5-axis cnc porting), and sold by Mullins Race Engines. With quality assurance as our main focus, this product will not have a production type mind set. This product will not be sold in parts warehouses.

Why did we do this?
First and foremost, the reason we wanted to do this, was to offer our engine customers a cylinder head that was more powerful and of better quality than what we can buy. By doing this in-house, we can keep a very close eye on quality control, make changes at will, and offer a cylinder head that no one else has to offer.
As an engine builder that builds 150 - 200 engines a year, buying cylinder heads that are not to your specifications presents a bottleneck problem in our shop. We are just like anyone else, spending $1400-$1800 on cnc machined steel or aluminum castings that are (SUPPOSEDLY!) fully machined and ready to go. The problem is they are far from that! Once we get these fully machined heads, we spend a solid day and a half prepping them to our specifications. Some of the issues that have to be addressed are:

1. cheap valve guides
2. inadequate push-rod clearance (we use 3/8 and 7/16 push-rods)
3. the cc's of the combustion chambers are not correct
4. inconsistencies on porting due to production-based facilities (which makes one engine run differently than another).

These problems arise from the fact that all of these production manufacturers are trying to provide a cylinder head with a universal fit. We have developed our head with an engine builder mentality---for the hardcore-type racing engine.

What we have to offer
Our first head available will be a 23 degree aluminum head. We will offer it in a 227 or 238 cc runner size. We have worked with Brodix to make a casting to our specifications. This custom casting will be sold to Mullins Race Engines exclusively from Brodix, due to the fact that it was developed by Mullins. It will have a very high quality manganese bronze valve guide to accept a 5/16 valve. The smaller valve stem helps with valve train control due to the lighter parts. It will be fully cnc ported at Mullins Race Engines facility. The push rod openings will be able to accept a 7/16 push rod, and come with a 64cc head that does not require any extra machining. We will offer these castings to other race teams and/or engine builders that want a competitive edge. We will work hand in hand with anyone willing to invest in our head packages. I have tested and dynoed all types of 23 degree heads, and I will guarantee this new cylinder head makes more power than anything available today. We are in the process of developing a steel head with the same ingenuity. It will be available soon.

Why 23 degree?
In some peoples' minds, this is a controversial subject. In my mind it is very straight forward. I would say it is no surprise that building engines for dirt modifieds is our primary work. We build engines for some of the most successful teams in dirt modified racing today. Working with drivers that are highly competitive and skilled keeps us on our toes. As an engine builder it helps us find ways to make these cars and their drivers perform better from all aspects. The engine performance aspects we are always trying to improve are:

1. Does the engine have the power to set fast time on a heavy 1/2 mile track?
2. When starting on the front row of a race or a restart, do I feel that I have a competitive advantage?
3. When the track gets slick, will my engine have a more driveable power curve than my competition?

These are all questions that I have dealt with for years. Due to these questions, I have worked on my product and refined it. So with all this being said, the question is "WHY 23 DEGREE HEADS?" I can say with 100% confidence, the 23 degree head is the way to go in dirt modified racing!! The question has always been "Can we make the big power?" It is very common to see horsepower numbers in the 750 hp range with our 23 degree head packages. We pride ourselves in setting fast time at Volusia County Speedway during Florida Speedweeks by making this type of power. We know that when our customers are starting on the front row of a heat race that we have the advantage with the air speed of a smaller intake runner that a 23 degree head provides. When the track slicks off, this 23 degree head drives better across the slick. This is due to the fact that it does not suffer from that soft throttle peddle feel of the big cylinder head. I have dynoed some of our engine competitors 15 and 18 degree modified engines. I have found that the engines are down on peak power compared to our 23 degree packages. I claim this due to our very refined combination.

Speaking of a soft throttle peddle---can anyone relate to this problem? The track is slick with some bite on the bottom of the track, and you roll off into the corner with your left side tires in the bite. You pick up the gas, but the peddle is a little too soft to hold the car from pushing. Then your nose slides a bit, and now you're getting off the corner with your rear tires out in the slick. At this point, you are looking at the guy's left side that was behind you going into that corner. Your brain will naturally react to make a change before you enter the next corner. When you get there, you realize to step on the gas harder so the motor will try to pull you through the push. What happens next is that the motor will bog for a split second, and then it will come on like a light switch! This is right when you are trying to keep traction in your car! When this occurs you will naturally start backing out of the gas. I have never heard of any type of suspension that wants you to be on and off the gas.

In a perfect world, you should be able to go into that corner, give the car enough gas to load the suspension and keep the nose from pushing. Then as you come off the corner barely pushing the throttle forward to the point of breaking traction---THIS IS FAST! Going into the corner and jumping up and down on the throttle due to a soft motor (where the cylinder head is too big) only causes problems that you cannot fix with suspension changes. My theory is that the 23 degree head is the best of all worlds in dirt modified racing! We are making over 125 hp more than we were five years ago. I also like the fact that 23 degree parts are less expensive than 18 or 15 degree parts. These parts include the head castings, intake manifolds, pistons, and valves.

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