Before reading this thread please read my thread titled, "Badger Midget Engine Program Success."

Due to the number of messages and questions I have received regarding the Badger Midget engine program, I thought I would start another thread and show you in pictures how we build Honda engines for the Badger Midget series. Keep in mind we do this in a small two car garage!!

I will not show any proprietary information or trade secrets so please don't ask about those things. Serious questions are more than welcome.

I am also going to point out the areas that differentiate the Badger engine program and cause the cost to be so much lower. This way everyone can see factual information on how these things cost half to 1/4 that of the other engines.

Below are some key points to remember about the Badger Midget engine program as well as some suggestions.

1. There is no titanium allowed except for valve spring retainers. Since the DOHC 4 valve provides a much smaller and lighter weight valve we DO NOT need TI valves!! Just eliminating ti valves alone more than doubles the time between valve jobs because ti valves are nowhere near as durable as stainless steel. It also reduces the cost of the engine by approximately $1600!! Also, the life of the valve is drastically increased as well. Many engine builders today won't even do a valve job on a ti valve and simply throw them away instead. Stainless steel valves are much easier to do a valve job on so we save some cost just by being able to reuse them multiple seasons.

2. The maximum limit in Badger is just over 146 cubic inches. Due to the architecture/design of these engines, going too much larger than that causes the sleeves to be too thin for a racing application. Yes, USAC allows these engines to be 153 CID. Realistically, the biggest you can go is just over 151 CID without causing reliability concerns. The stroke of the Honda engine is 99mm or 3.89764 inches. Therefore, to give us a little room for rebuilds we are going to start with a 87mm (stock size) or 87.5mm piston.

3. The Badger Midget engine program does not allow porting. You must run a cylinder head that is stock as cast by the manufacturer. No epoxy inside the port to change the size or shape either. Stock as cast means stock as cast. The best CNC ported heads on the market will cost you around $2500 plus the cost of the cylinder head core. Therefore, staying with the stock port saves us another $2500 on our build. Badger officials scope the intake at every event to check this for legality.

4. You must run a production crankshaft. This means it must be made by Honda. You cannot lighten the crankshaft counterweights whatsoever!! The crankshaft can be balanced. The Badger officials reserve the right to pull a pan or scope your engine to look and check this. The Honda crankshaft is made from a forging and is very very strong. The cost on a new crankshaft is under $300!! Last time I bought a new W9 Mopar crank it cost me $2800 by comparison.

5. You must run a production block! No aftermarket blocks allowed. You will notice that many of these production engines use an "open deck" design (except the Ford Duratec). This is because car manufacturers try to make them as cheap (less material less cost) and light as possible.

So far just on what we mentioned above we have reduced our cost by approximately $6,600.00.

The first thing we need to do is come up with an engine. You can do this two ways. One is to buy a brand new cylinder head and block from a parts supplier or we can buy a used engine from a salvage yard. Its entirely your choice. Just know that buying new will eat up some of our cost savings. I recommend buying used. Two reason for this. 1. We are throwing away most of the internals anyway and 2. Blocks that have been heat cycled thousands of times are going to be more durable.

So, now we want to pick the engine of our choice whether that be a Ford Duratec, Toyota, Chevy, Mopar, or whatever. We are going to pick a Honda. The engine we want is a K24 out of a Honda CRV manufactured between 2002 and 2006. The reason for this is because the cylinder head has the water exit from the side of the head not out of the back. If it were to come out of the back it would hit the motorplate or cross tube at the top of the motorplate in the chassis!! The cylinder head we will use is a PPA. You will find PPA cast right into it.

To give ourselves the best chance of finding an engine quickly and easily we are going to use http://www.car-part.com. This site searches thousands of salvage yards nationwide. Here is a pic of our search.

Now we found our engine!! Here is what our engine looked like from the salvage yard. You will have noticed in your search for this engine that it asks you if you want the Japan or England built engine. The engines are the same the only difference is where the castings were made. So pick either one during your search. This engine cost us $650 total. Last time I bought a new block for a Mopar W9 engine it cost me $6500!! Currently, you can buy a brand new W9 Mopar cyl head for between $1100.00 and $1300.00 but those are NOT machined!! We just saved another $8,000 on the cost of our engine! Total we are now up to almost a $15,000 reduction from a purpose built engine!

We will use the block and cylinder head for sure. One could use the crankshaft as well. Just be sure to have it magnafluxed and check to be sure its straight. If you can't do that yourselves someone most certainly can help you.

Now we need to take this engine apart. Valve cover, pan and front cover come off first. Make sure to drain the left over oil out of it first or you will have a mess.



Now we have the pan off. You can't see it here because it has already been removed but there will be an oil pump and balance shaft assembly on this. This can be removed and thrown away because we will dry sump this engine!



Now we have the valve cover off and we can begin taking the camshaft assembly off of the top of the engine. Make sure you have plenty of metric sockets including impact sockets.



Now our front cover is off. To move forward we need to remove our chain tensioners and chains that we will replace.

Now we pulled the cylinder head off. You can see that this engine had an excess amount of blow by on one cylinder. Everything else looks to be in great shape. How would you like to have just bolted this in and race? Not me!!



Here you can see the engine with the cylinder head off. Again, its worth noting how wet number one cylinder is because of the oil blow by issue. Nothing to be concerned about because we are going to rebuild this engine from the ground up. But could you see have running this engine? No way!



Here is one of the pistons out of the engine showing the oil blow by even better. Look at the wear on the pistons as well and this was a low mileage engine. Not a race engine as it sits, but once we rebuild it, this engine will rock!



Now we can see the block with the rotating assembly removed. Looks good and clean with no issues. Just needs to be degreased.



Now we have all our parts disassembled and laid out. We want to keep the cam towers for sure and maybe some of the bolts to be reused. Here you can also see the girdle! Yes thats right, no main caps! The bottom end of these Hondas are strong. If you look closely Honda even puts steel inserts at the main bearings for durability.

We have taken everything apart. We had someone degrease everything and look how nice everything cleaned up!







Now you need to decide what direction you want to go in and how much you want to spend. Before I mentioned that these engines typically are an "open deck" design. This is NOT suitable for a racing application. If we don't do something to our block it will crack a sleeve or blow head gaskets. You have two options. 1. You can purchase and install a "block guard" from a reputable company such as SuperTech or 2. You can send your block out and have it machined and have new sleeves installed. We recommend Darton Sleeves if you go that direction. This process is actually going to eat into the money we saved a bit. A block guard will cost around $100 and installing Darton Sleeves will cost around $1,000. We recommend sleeving the block (we have raced the Honda both ways) which will give you the most longevity out of your investment.

Block Guard


Darton Sleeved Block

If you have made it this far with your engine, you have already done more than most people do on their own engines today! The next step is to decide whether you have the tools and the ability to go further. Can you bore or hone your block to the correct size and make sure the cylinders are round? Can you deck a block or head? Can you check bearing clearances (without using plastigage)? Can you file piston rings? Can you time cams and then check valve to piston clearance? Can you design and mount the items needed to hold your ignition system components on the engine? If you can't do these things and a lot more) you are going to require some help. However, if you did everything to this point you have already cut a lot of labor cost from your engine!

I will post more pictures soon showing more machining and final assembly!

Nice looking crank. Any idea of the material?
How is the Block Guard held in place?
How deep it the Darton sleeve? How is it held in place?
Thanks for the information.

The Honda K24 crankshaft is a forged steel crank. I do not know the alloy. I can try to find out for you and let you know. Our crankshaft has two seasons on it thus far with no issues. We purchased it brand new for $284.00.

The block guard can be installed multiple ways. Some just press it in, others press it and then weld it in place, and some press it in and use red loctite or epoxy.

The Darton Sleeves are the full length of the original sleeves. They are a press fit and sealed with o-rings.
Here is a video of a Darton Sleeve install on a Honda K20 block. This is NOT my block but it's the same install process.

https://youtu.be/rVPCAdhcN3w

Thank you for your questions and interest in the Badger engine program.

Anyone besides me that can't go to page two?

Even though it shows one, I don't think there is a page 2 yet. Must be an error.