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C. Ludwig 06-13-03 09:14 AM

Bench racing...
 
Throwing around ideas for a new car. I got that tub that's asking for something. Wanting to do something with more power. Not really concerned about it being really competitive at first. Just want to drive something that is a bit more challenging than my ITS car. So.... I'm thinking ITE/SP/Super Unlimited type stuff. Basically just wanting some feedback on a couple ideas I got going through my head. They are:

1)Turbo 2-rotor.
Can make serious power, fairly easy, lots of good info and parts available. Apex seals don't like boost being the only down side.

2)3-rotor, injected, NA.
It'd be different and that's worth alot to me.:) Probably more expensive at first. What kind of power can be made with a good port job? More reliable than a turbo motor? If ITE rules require the car be built to some pre-existing set of rules, any rules, where can I find a series that allowed a 3-rotor? GT-2? GT-1?

Just dreaming.:D

Chris

wakeech 06-13-03 12:42 PM

the NA 3-rotor would be a more Renaissance, artful approach to power making, IMHO. if it was me, and i could afford it, i'd go all-motor ('cause that's what i know the most about, tuning-wise).
boosting is wicked cool, but supremely complex, much more Baroque in flavour... ;) not to mention i've still got lots to learn about the "perfection" of comprimise in high-performance turbo tuning.

Mld>7 06-13-03 01:03 PM


I got that tub that's asking for something.
A tub for what? Depending on what it is will make a difference!

If your talking ITE then those cars don't need a tub. You can just use a standard cage like any ITS car. If your gonna be running an ITE car then I would run a ported turbo 2 rotor if your good with that sort of thing. Prolly a bridge port and never go above 15lbs of boost. That should make aprox. a little over 350hp. But if your not confident in tuning a turbo rotery then id stick with N/A because things can get really messy if you don't know what your doing. With all the shit that your gonna take outta the car to lighten it up it will prolly feel like about 500hp. If you do it right that will be more then enough to make a little rocket and the 2 rotor will help with that 50/50 weight distribution that you wanna go for. Btw, could someone correct me if I am wrong, but I don't think that there are any classes for road racing that allow 3 rotors in them. If there is though, just screw it all and go N/A 3 rotor.

If you have a tub for an open wheel car then a ported N/A 2 rotor will be more then enough. But there are gonna have to be some major mods that you will have to do to make any rotery fit on a tub made for a piston engine. Unless you went out and bought the brand new Van Deimen Formula Mazda car. They are made to fit the new Renisis. Actually I don't think that either the engine nor chassis are even for sale yet though?..

Either way good luck and let us know what you choose. ;)

Btw what car are you using for ITS?..

C. Ludwig 06-13-03 01:30 PM

By tub I mean an extra FC unibody. The ITS car is an FC. Hmmm, what happened to my sig?

Jerk_Racer 06-13-03 04:05 PM

I've seen N/A 20B's put anywhere from around 450ps to 480ps IIRC. But these were stripped down blocks with just a stand-alone ECU and sports injection (ITB feul injection). I've just seen them in Japanese magazines over the years. If that's the case then I don't see any problems trying to squeeze out 350hp or so and still maintain a decent amount of piece of mind at the track.

C. Ludwig 06-13-03 05:02 PM

Whether it's turbo or NA it'll get a quality stand alone unit.

I know I've seen a car advertised in Sports Car as a GT-1 or 2 that had a 3-rotor. I haven't checked the Cen-Div rules for ITE but I'm pretty sure they're structured so that the car must be built according to some pre-existing rules. You just can't "run what ya brung". So if a 3-rotor is allowed in a GT class (why don't I get my GCR out?) then I should be able to build a wanna-be, uni-body, GT car and just run it in ITE for fun.

Ah, it's all conjecture at this point.:D Keep the info coming.

Silkworm 06-13-03 07:34 PM

Mines either getting a T2 motor for ITE, or a V8 eventually (read 3-4 years from now)

(oh the horror)

LOL

PaulC

C. Ludwig 06-13-03 07:48 PM

Hadn't thought of a V8. That'd be interesting. A 500hp LS1 woul be easy enough to whip up.

C. Ludwig 06-15-03 09:23 AM

Guess I might lean toward an NA 3-rotor. Just looked at the Cen-Div SP rules and an under 2-liter, NA motor falls into SPU. Sounds like it would make a decently competitive package and be hecka fun....and LOUD!:D

Now I just have to wait for the money tree to bloom.;)

maxpesce 06-16-03 09:59 AM


Originally posted by C. Ludwig
... Just looked at the Cen-Div SP rules and an under 2-liter, NA motor falls into SPU.

Check your rule book again I have NEVER heard of ANY sanctioning body that classifies a 20b as UNDER 2 liters, they are usually clasified as 3.6l (imsa) or 4l (fia) the LeMans winning 26b ran at the same weight as a 5.2l piston car under fia rules. IMSA settled on a 1.8x equvilancy formula for side port 13b's so they could run in the under 2.5l class (GTU). and 2x for PP 13b's forcing them into GTO, the 20b's were rated at 2.6l side port or 4l PP for min weight purposes (iirc).
Even SCCA clasifies a stock ported 20b as a 3l (1.5x eq).

tims 06-16-03 10:11 AM

a three rotor peripheral port engine with proper porting and exhaust tuning should be approaching 480hp. a fellow racer has a 13b PP that is making 320hp to the rear wheels. engine builder thinks 480 is a realistic goal. could be run in GT1 but would be killed by the ex tans am cars that regularly run. a 13b PP in GT2 could do some damage in regional races.

C. Ludwig 06-16-03 11:54 AM


Originally posted by maxpesce
Check your rule book again I have NEVER heard of ANY sanctioning body that classifies a 20b as UNDER 2 liters, they are usually clasified as 3.6l (imsa) or 4l (fia) the LeMans winning 26b ran at the same weight as a 5.2l piston car under fia rules. IMSA settled on a 1.8x equvilancy formula for side port 13b's so they could run in the under 2.5l class (GTU). and 2x for PP 13b's forcing them into GTO, the 20b's were rated at 2.6l side port or 4l PP for min weight purposes (iirc).
Even SCCA clasifies a stock ported 20b as a 3l (1.5x eq).


Good point. Never thought of a conversion factor. I just went by what the 13B was listed at in the ITCS (13xx cc). At any rate it appears it would be next to impossible to find a region that will hold specific U/O classes. From what I've seen most will only offer SP (U and O together) as a catch all. So.....


Chris


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