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I am preparing a Super for time trial use and eventually full race. I have a prepared 2 liter motor (thank you Chris) ready to go. The Super has (had) a 1600.

I would appreciate any and all advice, but would like to start with a few basic questions.

1. To mate the 2 liter to the 1600 gear box, what is the best approach? Or should I say, which is better, to use the 1600 box or 1750, or a 2 liter? Aren't they all the same, just different bell housings?

2. I need a flywheel and a clutch. Any suggestions?

3. I need a radiator. Go with stock or is there an aluminum one available?

4. Ignition. Open to hear suggestions.

5. Fuel system. I have dual 40's on the time trial motor, but will have 45's on the race motor. Best fuel cell? Best fuel pump? Any tips?

6. Brakes. I have heard to go with ATE dual piston style. What is the next step up? Which is the limiting factor for late braking? Is it the limited tire size or the rotor size and pad overheating?

7. More brake questions. The car has floor pedals. Any benefit to converting to hanging pedals? Later model or Tilton?

8. Roll cage reccomendations. I imagine that there is quite a bit to be gained in chassis stiffness with a well designed cage. What are the best points to pick up? cross braces? door braces? penetrate the firewall?

Let's get those experts out there to respond. This thread could become a great resource for all of us
 

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Hmmm, interesting project:

1. If the ratios of the any box are closer use that box. This will keep the engine spinning harder. I do not know if there are differences but assume that the 1600 might be closer ratios than a 2000 due to less torque.

2. Use a race clutch, ie. ceramic, without springs. The changes will be much quicker as the power is instantly transferred, ie. you do not have to wait for the springs to aborb the power. Harder to drive with but fantastic on the track.

3. Not sure about Rad.

4. Electronic to save maintainence ... you will be busy elsewhere :)

5. Go with the 45's as you can run better sized venturis ... I used to run 45's on a 1600cc Sud motor, so 2000 Nord motor probably could go as big as 48's. Do not know the best fuel cell, and cannot remember the pump I used ... but the standard mechanical pump can do the job for most Nord engines.

6. Forget late braking (except for passes) the braking point is determined by the maximum speed through the corner and best excit speed ... that is what matters not being the last of the late brakers. BUT saying that yep go for the biggest vented disc and 4 pot caliper you can fit inside your wheel.

The limit is complicated but design the brake so that it beats the wheel and then you can change pads and master cylinder sizes until you get great bite and feel ... and thus the driver can control the brake locking. You do not want to beat the wheel by too much, but better to design the rotor and caliper so that it will, and then back off the braking effort by changing master cylinder sizes. Obviously if the rotor and caliper combination are never good enough to beat the wheel you will never be able to optimise your brakes.

7. Floor hinge is the way to go because it keeps the weight down low ... but you MUST install a tandem brake master cylinder, ie. a race brake tandem master cylinder, so you can vary the braking effort between front and rear. Don't skimp on this ... You do not need one that is adjustable while racing, just must be adjustable so you can set it during testing.

8. Rollcage must connect the suspension load points to stiffen the car. Best to think of the rollcage as a space frame and triangulate as much as possible. While safety comes first, remember that the tubes add weight so design it, don't just keep adding tubes.

Have fun. Motor racing cost a bunch, so be prepared and my advice would be to start with close to standard mechanicals, so you can learn the art of race driving while the car is relatively slow and easy drive.

Once you have the car dancing on the limit everywhere and are beating much more modified cars with your humble standard machine ... then it is time to start the improvement came. Expect to go slower at first because modifications make the car harder to drive and less tolerant ... but ultimately faster once mastered.

Have fun.
Pete
 

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jeff,

your super already has hydraulic pedal. it has the same tranny as a 2 liter would. there you can leave the tranny that in it, in the car. all 5 speeds are the same ratios.

paul spruell in georgia has all the good racing bits you will need. if its a track only car, go with the KBR pressure (early 911 S type) plate and AP Racing clutches...I stock these

radiator...use the original one and have a couple rows added to it. we did that on mine and fabrizio's race cars and they don't run hot. also, throw some aluminum around the radiator to push air to the radiator.

fuel cell, go with fuel safe (bend, oregon) they have many cells that work. make sure it has a metal or aluminum box around the plastic bladder if you want to vintage race it, it's required. fuel pump, i use the good ol bendex electric pump.

brakes... vw bus brakes up front with hawk blue pads and porterfields in the rear. the big calipers use the same pads. the brake pad set up i mentioned works best, got rid of all my brake fade.

fabrizio and i still run the florr pedals. one day we will move to the tilton set up. you have your own master cyl for front and rear brakes with it and it makes heel toe a lot easier.

sparco makes a roll cage for the car. its the one fabrizio and the chris kattchee have. its a full 6 point cage and they added bars to it; door, rear cross, and a couple additional ones. it's a great cage.

lemme know if you need to know anything else.
 

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****, Anthony, you've just cookbooked a hell of a recipe for a successful 2.5 Challenge car, great response!

I kinda like my bottom feed pedals, I find it pretty easy to heal/toe with them. I think they're easier than a stock hanging pedal setup.

He didn't ask about diffs, but I think you run a 90% lockup 4.56lsd, no?

Regards,

Steve Schaeffer
 

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i still have a 5.12 locked rear end. fabrizio and richard are running the 4.56's with 90% lock up. fabrizio will have a locked 5.12 for buttinwillow in september.
 

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I just got off the phone with Jim Steck, and he has a new light weight clutch/flywheel system. Sounded like a real nice system.

Also, I've talked with a few other racers (Mike Besic), and heard a few stories- you might not want to use a solid clutch (non spring)... They are there to also dampen out vibrations between the engine and trans (as well as making engagements smoother), as I've heard a few transmissions that have been eaten by the NVH it takes from the solid connection.

Jim and Paul Spruell work together on quite a bit- the windage tray that Paul sells is made by Jim.

http://ourworld.compuserve.com/homepages/4sfed/

Eric
 

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disks

A good difference or a bad difference? Please elaborate!

I'm running a custom Rugh flywheel, with the old 105 tooth starter ring on it to clear my 1600 bellhousing, a '69 911S pressure plate, and a Spruell ferodo-lined Sachs disk. I looked for a lighter disk but could not find anything. I was warned to stay away from a solid disk for the aforementioned reasons.

Regards,

Steve Schaeffer
 

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Borrani,

A solid clutch disc (ie. no springs) is a huge difference to drive compared to a normal road clutch. BUT there is too things that make this difference, they are:

Clutch disc lining.
Springs or not, or even rating of springs.

I have raced a car with a solid clutch and ceramic linings and it was amazing ... but you CANNOT slip it and the gear change is instant, and this means that the drive train is NOT treated nicely by the arrival of power but very suddenly.

The springs are in a clutch disc to take this shock out ... but in doing so make the gear change slow, ie. power takes that little longer to be put to the rear wheels.

Now if you had a solid clutch with more normal linings you might be able to slip it a bit and still have some advantage of quicker changes ... A ceramic lined sprung clutch would not work well as it would kill the springs I think.

Anyway the conclusion is:

A ceramic solid clutch would be a big pain in the arse for driving through city traffic ... in fact with my race car I used to just pop the clutch and bang and use the rear wheels as the clutch.

You can actually chug away with practise with out spinning the rear wheels but it take practise.

Thus for track racing get a solid clutch ... got to be worth close to a second a lap, but for everything else just get a higher performance road clutch. Thus ignore my original recommendation (previous post) if this car is not a track only beast :)

Pete
 

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Pete,
Jim mentioned to me once that Jack Beck destroyed one of his transmissions in one track session with a solid clutch. This is on his GT5 race car... I'm not sure what his solution was. And I know Mike Besic has seen accelerated trans wear with the same.

Its not the engagements that are the problem, its the vibrations from the firing.

YMMV....

Eric
 

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no springs on the clutch beat up the rest of the driveline. more vibrations and its either on or off the clutch. i seen it mess up tranny's driveshafts, and rear ends. also, the center portion of the clutch disc that has the opening and the grooves for the spines on the input shaft wears out. the **** clutch disc was always loose when i pulled my tranny out. ap racing clutches are good and everyone uses them out here. after all of us switched to them, we did not notice a change in lap times. now, all our stuff lasts longer because the springs are helping out the driveline. in the end, it's all personal preference. seems like the current set up to go with is the alumium flywheel with ap racing clutch and 911S pressure plate.
 

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Excellent info, Anthony. What is the thickness of the AP disk? I believe Alfa uses a bit thicker disks, 0.383" if memory serves. Paul Spruell sold me a disk that was 0.045" thinner, and I remember him saying that was more of an industry standard. I therefore cut my new flywheel down 0.045" so the geometry was hopefully more correct, meaning the clutch fingers were as flat as possible. My clutch disk was around 0.340" thick I believe. Do you have a weight of the AP disk? I believe my disk was 2.70lbs, which, incidentally, is the weight of the starter ring gear.

Have UPS scale, will weigh!

Steve S.
Weight weenie
 

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Its not the engagements that are the problem, its the vibrations from the firing.
Hmmm, that is very interesting and something I had never thought of. Guess you would be right, but I never had any driveline problems with my use of such a clutch. Then again my gearbox was rated for 100 hp more than the motor produced (yes I know not the ultimate in F1 design ... but atleast reliable :)).

When you are racing the engine is spinning very fast so I guess that the firing vibrations would be some what smoothed ... and this is another reason why they would be stupid for road use, ie. cruising at low revs and thus big vibrations.

Pete
 
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