SCCA G-Production 914, Anyone runnig one? Options

[don9146]

We have people on the board that road-race their 914s in F-Production and E-Production, but does anyone race their car in G-Production (on the board or know of someone that does)? A quick glance through the rulebook makes me curious about a few things with the 914 in that class:

1. How fast are the G-Production cars compared to ITA, ITS, and F-Productions cars?

2. How can you modify the 914 engine for this class and still use the "original type fuel-injection only" (from page 272 of the 2006 GCR)? Obviously, 10.5 to 1 compression pistons and a 0.420" lift cam would cause the stock F.I. system to go nuts. So what "original type" can be substituted?

3. What type of reliability can you get from a 10.5 to 1 compression type 4?

4. Is the 914 competitive in G-Production?

5. Is the popularity of the Production Category cars waning across the U.S., or are there just few of them around where go to amateur races (Road Atlanta, Barber Motorsports Park, St. Louis)?

6. Would racing a 914 in G-Production be any cheaper than running a 914 in F-Production?

I am looking at a 944S that has been built for the ITS Category this week. I would like to road race a 914, but ITB would be too slow for the money and time, and an F-Production car seems too expensive and time consuming. Would a G-Production car be a good fit?

Thanks,
Don

[Thorshammer]

So lets look at this as best we can.

G prod Interesting:
I doubt this combination will make competitive HP. @2000lbs making 150 or so HP which is what it will take.

My ideas:
Engine:

Intake system:

So you can have a 1.8 liter, so the intake must remain stock, So start with an L Jet intake, and you will want to use a stand alone fuel managment system, that way you can remove the air flow meter. It will be very important to have a cool air box above the throttle body that is sufficient in air volume, and the addition of a very large velocity stack will be needed on top of the TB. Remember that you will be fighting the length of the intake tract, so the cam grinder and exhaust maker will have to be very sharp.

Cylinders will be Nickies, of course, the 94mm pistons will need to be the very lightest things you can get your hands on. 20mm pins I would suggest , because the intake will be the RPM limiting factor, JUST THINK RESTRICTOR PLATE RACING. I would also use a very very low tension ring pack, like an XC or the like. I personally would run a two ring piston with a vacuum pump, but then again I am a whack.

Con rods will prove to be a big problem, I have a real problem with this one, THERE IS NO COST REDUCTION IN RETIANING STANDARD CON RODS. But the time you prep them, you have just as much in rods as you would to buy some carillos, and they will last longer than the car. The stock rods we used to throw away after 40 hours, then shot peen,rod bolt and polish the beams after magnafluxing them, what a pain in the ass.

Good on you with the crank, I would turn it .040 Ion nitride it after REM process the entire crank, then a couple small oiling mods.

Straight cut cams gears, REM finished

Cases, After getting a real good set, I would port and polish the entire case paying special attention to airflow underneath the pistons and how oil is going to drain off of everything, then maybe a crankshaft scraper of some sort, maybe Jake has an idea or something on this already.

Oiling system. most of what I would do will push the rules envelope, but I would instal a 3 quart accusump, a oil trap at the bottom of the crankcase and a belt driven vacuum pump to draw the crankcase down.

5.5 Tilton Clutch with one tiny little itty bitty flywheel.

Jake can build this, but not sure of his available time, Len Hoffman can do the heads and manifolds. With the lack of compression and camlift, this engien will have to burn the available mixture very well.

Keep the oil as low in the crankcases as possible, while still getting good oil flow?? gonna be tough.

The stand alone injection will be a density system like: Motec, DTA, Electromotive (not recommended). This will give precise control of timing and fueling events, and you will need this.

Coatings: Anything that moves gets something, True thermal barrier on the exhaust ports, DLC on the valve stems, Thermal dispersant on the heads.

DTM cooling shroud, ribbed belt drive for fan and vacuum pump, Remember you may use any crankcase evac system but it must not connect to the exhaust system.

Ceramic lifters, REM the cam, which must be very special, this will take a real grinder and alot of R&D

"Thats all I got to say about that"

Chassis:

Think as small adn as sleek as you can. How will it go through the air, If you want to build a closed car, don't do this project, if you want a high hoop cage, don't do this project.

Front should'nt need any flares at that track, rear should only need a very small flare, which I would suggest stretching the stock fenders.

You will need air from the front to the engine fan, by means of a front to rear duct, I would pick up the air via the small holes at the front header panel of the front trunk. You can't cut this out, but you can build an air dam that funnels all the air in the center of the car through these holes, on the trunk side build a small plenum, and have two three inch tubes throught he car and should provide excellent cooling for the engine, and some free HP (due to not having to drive th cooling fan as hard)

The front hood needs to fit perfectlyto the front fenders, as should the front bumper and front airdam. This is a must

Use Aircooled racings fiberglass windscreen, the standard Ginther screen is too low. and will not guide the air over the cockpit very well.

Fill the rear fiberglass bumper with house insulation foam, so it does'nt act as a parachute, it will also add a little protection in case of a rear end hit,

The air box should fit perfectly to the bottom of the engine grill and seal, so that all of the air that is cool goes in, not the hot air around the engine. Remeber it is getting fed by the front ducting.

Install the air deflectors at the bottom of the pan, it does make a big difference.

Headers, I would consider building a set of headers that will take the exhaust tubes foward, not rearward, I think there is something to gain there, and have the Final tube to exit in front of the wheel, out of the rocker panel. i would make it so that the collector could be changed and it could go out either way.

make sure the roll cage is built right in front of the targa bar, and that the vertical roll cage element allows you to tuck your head close to under the main roll hoop.
The front low hoop should be back from the inner dashpanel, so that the line from the main hoop to the front hoop will pas over your helmet, I would start by buying the seat,pedals and the windscreen and then going from there.

The chassis needs to be of adequate stiffness, Brett W and Kevin Groot have studied this I think.

Front mounted 8 gallon fuel cellshould be plenty,and use an in tank pump, I have run FI racecars on a single optima battery without an alternator, but it's up to you, gotta charge all the time.

Suspension:

Torsion bars, 22, 225 lbs rears, 1 1/8 front bar.110 wall, Konis 8610, call Roger Kraus, HPH etc, watch the ride height, as too low will screw up the front RC.
Again see Kevin or Brett.
Aways look to make the suspension as friction fre as possible, such as the rear inner pickup point relys on the flexibility of the inner point to adjust the alignment, I woudl suggest roller bearings and a spherical bearing in the inner point to keep it out of a bind. the outer is not a problem.

Limited slip in the trans.

All I can think of sorry to be so long winded.

Erik Madsen

Post Script: I would love to see someone with a max effort for one of these cars.