ITB CGT FAQs

[JShadzi at aol.com]

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[ Picked text/plain from multipart/alternative ]
Scott, first off, congrats for making this decision, I am very excited for
you and glad that you will be racing such a fine car!

> <<2 - Since suspension seems to be the main area of
> modification, what brands of spring and shock are
> available for the CGT, and what kind of experience
> have listers had with them?  I know this car isn't
> quite as popular as a watercooled VW, where there are
> dozens of brands from scores of vendors, but BTDTs
> with specific vendors will be very much appreciated.>>

Scott, with a front drive nose heavy car like a CGT, most of your suspension
mods should be focused on the front suspension.  I would recommend 2Bennett
or Ground Control coil overs, this is a must for a race car as swapping
spring rates and corner balancing will be a breeze.  Off the top of my head
I'd start with 500lb front and 350 rear in a race car, but you can buy
different rates and experiment with what you like, a spec-Miata runs like
800/300.  I recommend Koni double adjust race struts in the front, this is a
very firm yet compliant strut with a lot of travel, and adjustability (the
best feature, rebound and compression).  They are not cheap, but I know
you'll be very happy with them, we've been racing 4kqt cars with these struts
at all 4 corners with very good results.  In the back I wouldn't be as
concerned there, a Boge turbo gas or Bilstein should suffice.

For the front sway bar I would probably leave the stock bar as is, maybe make
some metal/poly bushings for it, and I would install a 4kq front bar in the
back.   Running a bigger bar in the back is key to get the car to turn,
trailing throttle will be a breeze.  Use green strut bushings in the front,
I'd make some aluminum bushings for the rear top shock mounts, the stock ones
move up and down about 1/2" during normal driving.  I assume you'll have a
cage in the pass. compartment, put a solid strut bar in the front, I'd move
the battery to the trunk to the pass corner to shift some weight to the back
and clean up the engine compartment a little.  Don't know if its allowed in
the rules, but we've run alternators off the rear differential, it only
charges while you're moving but that's fine for a race car.

Delrin A-arm bushings, nuff said.

Get rid of the stock rad shroud and put in a smaller electric fan, the stock
radiator shroud is quite restrictive and you don't need it for racing
conditions, plus it saves about 10-15lbs off the front end.

For motor mounts fill all the voids in the rubber with epoxy putty, include
the tranny mounts to really firm things up.  I also mod the front snub mount,
see following link: <A HREF="http://www.80tq.com/images/snubmount.jpg">http://www.80tq.com/images/snubmount.jpg</A>


<<> 3 - I've got the manifold and downpipe from a later
> 4kq ready to be installed in the car for a modest
> improvement from the stock CGT manifold, but does
> anybody make tubular headers that might be more
> effective?  (Again, this is for a naturally-aspirated
> car with essentially no internal mods, accoring to the
> rules.)>>

Ahh, my 4kq manifold lives on!  =)  There are not any tube header's readily
available for this car that I know of, but the tri-header flows really well,
probably most of what you'd get in a header you'll have.

> <<4 - I've got Mintex Red Box brake pads in the garage
> waiting to be installed (they're on the shelf next to
> some new rotors and calipers).  What's the word on
> good brake pads for track use?>>

Red Box pads are _street pads_ , not even that agressive for that matter, it
is marketed to the enthusiast market, it brakes about as well as a stock pad,
its main attribute is "low dust", which it is very good with.  For a race pad
I gushingly recommend the Hawk Blue, this pad is unbelievable, it is very
hard on rotors, but it can transform a 9" brake and make it feel like a 13"
big red, fade is negligible in the hardest driving.  Its the pad used in most
NASA spec racing including Miata, Rabbit Cup, Pro-7, etc, etc.
Realistically, if you drive the car well you'll be using the brakes minimally
anyway, an ITB car is a momentum car, carrying speed thourgh every turn is
critical, for example in a Miata at Laguna Seca realistically a driver will
never lift the whole way around a lap.

> <<A lot of what I'll be going through will be standard
> rebuild stuff -- for example, in addition to replacing
> the brakes, the right-front wheel bearing is loose and
> I'll probably replace both at the same time (since
> Portland International Raceway has mostly right-hand
> corners, meaning the left one will come under most of
> the stress).>>

Yes, I'd go thorugh the entire car, repack CV's or replace, all wheel
bearings, every replacable bushing, rubber hoses, plastic components, get an
all metal radiator (I have a good rebuildable core if you need one), if you
think it could be replaced, do it, if it fails during a race it will cost you
much more (not just a position but the whole experience).  I'd put in a
removable front end to ease working on a car, get rid of or re-engineer
anything that's in the way within the rules, make the car easy and fast to
work on.

> <<I'll take lots of pictures and document everything I
> can think of as we undergo the process.  I hope it'll
> provide some amusement for the folks on the Q-list,
> and I'm really looking forward to it.>>

Great, please keep us/me posted, let me know how I can help or be of
encouragement.

Good racing,

Javad