Ontario Race Fabrication specializes in head porting, as well as custom roll cages and roll bars.
Roll Bar & Roll Cages
ORF builds and installs custom roll bars and roll cages to CASC specifications.
Car weighing & Corner weightingORF has a fully digital corner weighing scale system that allows us to corner weigh your coilover suspension, this system gives exact weights at each wheel, the cost is $50 per hour.
| Basic and Installed | Cost |
|---|---|
|
4-point roll bar |
$900 |
|
6-point roll cage |
$1700 |
|
These two pictures show the instalation of a basic rollbar custom made for a Honda Civic. Click each thumbnail to view a larget version of the image. This rollbar is designed to be built into a cage with a ladder door bars. |
We can make any design you desire. Contact Ontario Race Fabrications for a quotation.
See Ontario Race Fabrication projects for additional examples of roll cages and roll bars.
Head Porting
An engine needs air to burn the gasoline: the more air that is available to the engine, the more gasoline that it can burn. When you allow the engine to have more air per cycle the result is more power.
If you look at other performance items, such as exhaust, headers, air intakes, and larger throttle bodies, they are all doing what head porting doesallow more air into the enginebut to a lesser degree.
In most cases, head porting realizes more power than other "bolt ons," however, that is not to say that the other modifications are not important. In conjunction, the modifications allow even more air flow and greater performance.
The biggest bang for your buck in engine power is adding a camshaft coupled with a good head porting.
Head porting is important because is OEM manufacturers often looking for the cheapest solution to increase their profits. When they do head casting, the port surface and casting lines left in the ports are not highly desirable.
In most cases, OEM head design focuses on fuel economy and low to mid RPM operation. This is fine for day to day use, but in racing we concern ourselves with higher RPM range, which is where the engine operates and generates power.
As you can see in our example (a Nissan KA24DE enginecourtesy of Asad from Freshalloy), the casting lines are very rough and the valve seats are not blended into the port.
These imperfections restrict the incoming air charge, and the exhaust, reducing the overall engine volumetric efficiency (VE).
In a naturally aspirated engine, our goal is to get as close to 100% volumetric efficiency as possible, meaning that we want the combustion chamber 100% full with an air charge so that we can apply 100% of the fuel burnable with the air charge. Forced induction requires a slightly different philosophy.
Pricing
Ontario Race Fabrications head porting pricing is very affordable. We offer a number of head porting, and connected, options.
Note: the average flow improvements vary, depending on the OEM head.
Prices are based on an aluminum 4 cylinder head. For exact pricing, or for more details, contact us.
You must deliver the head stripped down (no valve train or cams installed) and bring the intake and exhaust values, along with a new intake and exhaust gasket (ORF returns these unharmed)
Delivery is 1.5-2 weeks, for a 4 cylinder head.
Street Port$300 + tax
- Prepare intake and exhaust mating surfaces
- Port matching intake and exhaust
- Clean up intake and exhaust casting lines
- Polish exhaust and intake ports
Average flow improvement: 2-4%
Full Port$400 + tax
The Street Port, plus:
- Blending valve bowls into the intake and exhaust ports
- Minor work to the short side and roof of intake and exhaust ports
Average flow improvement: 4-6%
Race Port$500 + tax
The Full Port, plus:
- Reshaping port dividers, if any
- Reshaping intake and exhaust short side and roof
- Clean up combustion chamber hot points and casting lines
Average flow improvement: 6-15%
Intake Manifold Porting$80 + tax
- Matching head to intake manifold
- Porting runners ~6" into runner
Throttle Body Porting$50 + tax
- Cleaning casting lines
- Porting throttle body
Spark Plug Indexing$80 + tax
Indexing spark plugs faces the open side of the spark plugs' electrodes towards the incoming fuel injector spray.
Indexing the spark plugs is good for a few HP.
Head Flowing Services$150 + tax
Consists of printed head flow data in CFM at 28" and 500 thousands lift.

