Out with the old...in with the new...Britain's Racecar Development, Subaru Engine, Lotus Suspension! Time to go racing! Options

[Britain Smith]

For those who don't know me or the car, I have a '74 914 that is a dedicated AX car. It previously had a high compression 2.7 6-cylinder motor and made 205hp/205ft-lbs at the wheels. This set-up wasn't all that bad considering that it won the 2008 and 2009 914 Shootout events, however the quest for more speed continues.

Here is the car in the 2010 season trim.

(IMG:http://www.914world.com/bbs2/uploads_offsite/dragracevws.com-364-1291656786.1.jpg)

I have recently sold the 2.7L 6-cylinder engine and all the remaining 914/6 conversion parts. I have used the proceeds to fund the conversion to Subaru power. Now most would say that a Subaru conversion can be done on a budget, however I have found that the money goes flying out the window when doing something like this.

Regarding the engine...logical choice would be to go for a EJ257 2.5L USDM STi engine. However, all the SCCA rules for AX are built around displacement which in turn dictates the minimum weight. Therefore, I have gone with a JDM STi version8 Spec-C engine which is a 2.0L, twin-scroll, hand ported/polished, 8500rpm animal. I will get slightly less hp and torque numbers than the 2.5L, but save 150lbs of weight.

[Britain Smith]

Being out of town for a week got me out of the groove for a couple of days, but I started back in it last night.

The first thing that I tackled was the routing of the coolant lines for the turbo. The stock routing simply would not clear the firewall, here is how it originally looked.

(IMG:http://www.914world.com/bbs2/uploads_offsite/l17.sphotos.l3.fbcdn.net-364-1294082547.1.jpg)

After a little cutting and welding, they are now routed properly.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082547.2.jpg)

And here they are with the coolant hoses attached. The feed line comes from the reservoir tank and the return goes to the stock location at the back of the head.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082548.3.jpg)

In a previous image, you may have noticed that rubber coolant line ran very close to the exhaust downpipe...a little too close for comfort. I therefore constructed an aluminum coolant line that routes farther from the exhaust.

Here is the original rubber coolant line in place.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082550.4.jpg)

And here is the aluminum coolant line.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082550.5.jpg)

Another item that I had some comment on was regarding the structural integrity of the square tubing engine mount bar. I had plans to reinforce this from the beginning, but I needed to finish the mounting of a few other items before constructing this plate. It is 3/16" mild steel cut out on a waterjet and stitch welded across the entire length.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082551.6.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082551.7.jpg)

The aluminum coolant pipe will be supported with a bracket hanging off this plate.

The last thing I started work on was the mounting of the pedal assembly. I explored the option of bolting it to an aluminum plate then securing that plate to the floorboard, but the entire thing was going to raise the pedal assembly an additional 1/2" off the floor. I have now decided that I am going to weld in a steel plate in-between the floor ribs to reinforce the floor pan and provide a flat surface to bolt the pedal assembly in.

Here is the floor pan in the pedal cluster area, you can see the multiple ribs and recesses. (Ignore the brake master assembly in there, I haven't lifted the car off the lift to pull this out yet)

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082551.8.jpg)

Here is the steel plate that cut out to fit, there will be some vertical plates welded to the bottom of this to account for the variation in floor thickness.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082551.9.jpg)

And here is Tilton pedal assembly in its final resting place. The new pedals will take some getting used to, but at first pass I like them.

(IMG:http://www.914world.com/bbs2/uploads_offsite/sphotos.ak.fbcdn.net-364-1294082551.10.jpg)

More to come soon,
Britain