Engine Building

Rotary Engine Building is our Specialty

Rotaryengine.com has been serving customers around the world by offering the best quality engine rebuilds and rotary engine services for the past 19 years. Many people have not become aware of who we are or what we do because in the past we have been providing our engines and services mainly to shops and other engine builders. Due to some of the unique and proprietary parts and services we offer, much of what we do is considered to be quite unique and uncommon within the industry. In short, we have remained to be extremely busy and therefore have not had the need to advertise or solicit for new work. At the same time, we have always gladly accepted new referrals, but found that a larger portion of our business was still doing work for other rotary shops. Notwithstanding, a large portion of our clientele are private rotary vehicle owners and rotary enthusiasts. We always have and will continue to allow rotary car enthusiasts to deal directly with us.

What we have been told by all of our previous customers, both shops and personal, is how amazed they were to see such high quality services at low prices. REC thrives on using the best quality parts and at the same time keeping the cost of our products lower than our competitors. Most of our inventory is purchased directly from Japan and imported in quantity to keep costs to a minimum. With the buying power we have on all engine parts along with our in-house machining services, we avoid the middleman which in return saves our customers substantial amounts of money.

REC has recently expanded our engine building division enabling us to give you a wider variety of services, OME and customized parts. With our new wholesale direct program and “rotary points” system, our customers stand to save more money than ever before. Much like the rest of our packages, customers simply select a list of products that they wish to order, we then attach the lowest wholesale price we can offer to each of those individual products, then we simply add them all together.
(Some further discounts will apply. Please inquire for more information.)

Custom Aluminum rotary engine

Whenever purchasing one of our engines, we will always start with a base engine price and any added products or services become upgrades using a “add on” pricing system. We will explain below which items are included as a standard in all of our engines starting with our “base engine” configuration. You can then view an example of how the “add on” pricing system works.

All of our short blocks are engines which we refer to as “the Keg…” and at a minimum , is a fully assembled engine assembly with completely refurbished reused hard parts, and a brand-new internal rebuild kit. “The Keg” is delivered as a sealed unit with front cover and everything behind the cover installed. The eccentric shaft end play it set, the front hub is installed and the front main bolt is torqued. It is also common to ship the engine with the flywheel or rear counterweight installed and fastened with the rear nut. Depending on the year and model of the engine, and oil pan may be supplied and installed also.

In all of our engines, including base rebuilds, we will tear down a good usable core to perform the build with, then we will clean, measure, inspect, machine/refurbish, prep and install the new parts, then reassemble the engine. Any engines which will have the side housings reused will receive mandatory machining and lapping of the side housing faces. The special sonic cleaning procedure to remove the lapping compound is also included within this process.
Any rotor bearings or main bearings which are determined to need replacing will also be installed as a standard. The eccentric shaft is power polished with a special crankshaft polisher. All base engines will be fitted with two good usable rotors and rotor housings. The stationary gears will also be good reused parts. Any of these hard parts can be upgraded to brand-new or performance/customized components.
All of the internal seals, springs and O-rings are replaced with brand-new parts as a standard package. Base engines are fitted with new factory apex seals. Upgrade apex seals are optional as an upgrade.
Once the final assembly of the engine is complete, we will perform a compression test and a cooling system pressure test before the engine is released or fitted into a vehicle.

The below example is designed to help demonstrate how our “add on” pricing system works when ordering a custom built engine.


Lets say you want to order a customized race engine and the needs are a four-port turbo block with non-turbo internals. You also wish to have new rotor housings and a street port, and finally, you requires all of the necessary gaskets to install the external components.

To make it simple we will use some round numbers and choose a random model year for the engine.

So if the base price of a 1990 turbo engine was listed at $2000.00, this base price would represent the cost of a complete short block on a core exchange, meaning your old engine needs to be returned as a core to obtain this price.

Many of  REC’s upgrades are actually sold to the customer well below our cost. Rather than just tacking on the price of two brand-new rotor housings to the base price of the engine, we have a different philosophy.

The base price of the engine includes two good usable rotor housings. Although the cost of brand-new rotor housings can exceed $800.00 each, you as the customer will only pay a trade in proportionate cost for the housings. This will determine what the “add on ” price would be within this example.

REC guarantee’s the lowest price on all rotary engine parts, so the $800.00 (approx) list price of the housing automatically drops to $565.00 ea. after your wholesale direct discount. Then it you will receive a credit for the used housings which were already factored into the price of the base engine.

In summary, once you receive the credit of $250.00 for each reused housing (total $500.00) you’re net price to upgrade to the new housings becomes $315.00 each. A total of $630.00 to upgrade to two brand-new rotor housings. Something that is part of our exclusive program which is not normally seen within this industry.

Within this same engine example, we have demonstrated that you require high compression non-turbo rotors for naturally aspirated use. Again, you would receive a credit of $195.00 for each rotor, the cost of a brand-new 9.7:1 rotors through REC would be $471.00 ea (List is approx $700.00ea) so you’re net price to upgrade to 2 brand-new rotors is $276.00 ea, which is a total of $552.00 for the engine.

This actual cost of the rotors is well below the price which REC pays for these components.

REC also applies another benefit to the customer which falls into our engine rebuilding policies, every time a customer opts to purchase two upgrades, the third upgrade is discounted by an additional 20%. So if the customer chooses a total of six upgrades, two of these six upgrades will be eligible for the 20% discount. This discount only applies to service upgrades and not parts.

The street porting for the above mentioned motor which is normally charged out at $475.00 would now be discounted to $380.00.

The last “add on” which factors into this example is something that we recommend that all of our customers take advantage of when purchasing an engine from REC.
Every engine we build will require an engine O-ring kit to assemble the engine. But this kit does not automatically include all the necessary external gaskets to dress your engine before it is installed into the vehicle . These install gasket kits can be purchased from us two different ways.

1) in the first option consider that all of the rebuild O-rings are already installed and included in the price of the assembled engine. So all of the external gaskets you will need can simply be sold separately and purchased from REC at any time.
2) the second option, which is what we always recommend, is where we offer you a master O-ring/gasket kit which enables you to obtain all the necessary external gaskets at a much lower cost. A master kit includes all the O-rings necessary to rebuild the engine along with all of the external gaskets.

In most cases, when you receive your engine you will require all the necessary gaskets, washers and O-rings to install all your external components to the engine before it is installed. Purchasing the balance of the master kit separately is substantially more expensive.

REC can offer you a master gasket kit at a wholesale direct price which we have learned can save you up to 40%. When REC charges out the master kit to you, we then give you a credit for the O-rings which were necessary to rebuild the engine and the costs are already factored into your base engine rebuild price. In most cases, you will receive a credit of $170.00 and all you pay for is the balance of the costs of the master kit.

In the example of the 1990 turbo engine, REC will sell this kit to you for $316.00 (List approx $435.00) and after we remove the credit for the all rings you pay only $140.00. If you add up the costs of all the individual gaskets, washers and all O-rings the cost would be close to $260.00. Again, your costs from REC is only $140.00.

Our goal is to save you money but give you the best quality parts and service when providing our engine building services.


Please feel free to visit the store or contact us directly so you can get a good idea of total costs to customize the rotary engine you are looking for.



*All prices above area example and subject to change*