Hello everyone out there in rotary land. My name is Travis and I currently own a high end custom cycle business here in Texas called Iron Spade Cycles. I'm 40 years old with about 25 years experience building all kinds of race specific vehicles from rockets to race cars. I am a master fabricator with a BS in Mechanical Engineering and a BS in Industrial Design.

Although my business is motorcycle related in origin, I have been building some one-off custom cars as well in my spare time. My current auto related project is a radical design based on a Scott Robertson illustration I stumbled onto a couple years ago.



The body will be all hand formed 3003 aluminum with a 4130 space frame and suspension components. Suspension duties will be handled by a computer controlled active system similar to the Lotus Esprit of the 90's and 4130 twin A-Arms front and rear.

Wheels will comprise of a set of 19" center knock offs with 13" Baer Pro Plus brakes all around. Drive line will use a Corvette pumpkin in the rear and a 5speed box built for auto clutch and sequential shift paddle shifters.

I intend on building a 13B, or if I can find one a 20B, engine with a stand alone fuel management system and direct port injection. I will use a 50:1 Bel-Ray premixed, 105 octane, dedicated fuel source as this car will almost never see a fueling station. Ideally I would like to see around 300 HP as a peak and I'm not against Superchargers or Turbos but I would like to set it up as a natural intake.
I also plan to build this car as a Hybrid running a Hydrogen injection system as a co fuel to help extend fuel economy and increase HP output. This car will be very light (around 1500lbs. wet with 30+ gallons) with the CG riding very low in the chassis.

Back in 1990 to 95 I co-built and raced a Series 1 RX7 in SCCA GTS class here in Texas. Although Mazdatrix build our motors, I built the rest of the car and rebuilt the transmission for racing. We ran a spool in the rear end which was fast for the track but in hindsight I would run a limited slip in the future. On several occasions I had the engine apart inspecting the inner workings for damage and surprisingly it was always fine. Those motors could last through all but the most extreme conditions. Our car was fast turning top speeds in excess of 160 at Texas World Speedway, a track similar to Daytona International Speedway.

This project will consume most of the next couple of years to complete as it will require all of my spare time and spare cash. I will have questions, this I know!
Thanks in advance for all of your help and wish me luck. Updates to follow.

Later Travis.

 

Sounds like a great project.

300HP NA on a 13B is not too hard when you have a machine shop. A healthy full bridgeport will do it. Better yet, peripheral port the sucker and make more peak HP with a better torque curve.

A 20B for only 300HP seems like a waste, but it will have far better midrange and will do 300HP with only mild work (high compression rotors and a slight port job).

 

Now all I've read about Peripheral ports is that it puts all the power between 8000 and 10000 RPM, is this true? Would it then be like a two stroke race bike and make next to nothing for power off the bottom end?

This will be a street driven car so stop light to stop light torque and acceleration is still required. Could a 20B be built for say 450HP and then use the fuel management to effectively de-tune the engine allowing better drive ability? Also how much heavier is the extra third lobe? What can I expect to spend for a build-able donor 20B vs. a built and ported 20B?

I know I can find a 13B and build it myself and the only major cost involved will be the better apex seals and the high compression lobes. I've been porting all kinds of race engines over the years so as long as I can find or purchase the port schematics I can port these motors as well. But when I see pictures of Peripheral port motors the area of the block around the P Port look different than a stock block. It looks like it was purposely cast for P Ports. Is this a stocked item or are they custom made? If they are custom how much can I expect for a set of P Port blocks?


As long as we are talking about Peripheral Porting I've got a different question. If P Ports are designed for big top end power has anyone ever thought of utilizing both a P Port and side ports to effectively make more power across a broader RPM range?

I think the P Ports could be controlled by either a set of reeds as in a two stroke motocross bike or even a servo actuated power valve that would open and close based on the RPM the engine is turning.

So as the engine is started the RPMs are low and the P Port reeds or power valve would be closed only allowing air to follow the smaller more restrictive side ports which would create standard low end power and torque but as the engine rev's to say 6500 RPM the reeds or power valve begins to open allowing the intake to follow the direct P Port creating even more power from say 7000 to 9000 RPM.
Is this theoretically possible? Has anyone even thought to try it?

Thanks for you help. Talk soon. Travis