“Your first SM” - To build or to buy?
This is the question most people grapple with when thinking
about getting involved in the SpecMiata race series. In this article we
will outline some of the areas to consider when trying to decide which model
year car to purchase and whether to purchase an already completed race car or
building your own.
First of all lets identify the eligible cars, there are
currently 3 basic versions (see chart below) of Miata available for competition
in the Spec Miata series. Early 1.6L cars, early body style 1.8L cars, and the
newer body style 1.8L cars up to model year 2005.
Year
|
Weight
|
Restrictor
|
Size/Comp
|
Notes
|
|
1990-1993
|
2325
|
None
|
1.6L / 9.4
|
Intake design is
free with cone style filter.
|
|
1994-1995
|
2350
|
47mm
|
1.8L / 9.0
|
|
|
1996-1997
|
2350
|
45mm
|
1.8L / 9.0
|
No car was
officially made in 1998.
|
|
1999-2000
|
2425
|
41mm
|
1.8L / 10.0
|
|
|
2001-2005
|
2425
|
41mm
|
1.8L / 9.5
|
|
Choosing a car to build or purchase
Which Car should I get? I would say that depends on several
things, your weight being one of them. The early 1.6L cars represent 85%
to 90% of the cars in the class due primarily to the low cost of the donor car.
If you weigh over 210lbs then you may want to think about the later model cars
so that you can get the car down below the race weight so you can add back
weight as ballast to help with the overall balance and corner weights of the
car.
Some cars will work better at different tracks. The
1.8L cars have better torque numbers, so they can get off the corners a little
better, but the 1.6’s have a little better top end. 1.8’s use a Torsen
limited slip, and the 1.6’s use a clutch pack style limited slip, or the
recently approved 1.8 style Torsen as long as you keep the correct final drive
ratio. The 1.6’s have adjustable sway bars front and back, the 1.8 cars
do not. Of the top 5 finishers at the runoffs, 3 were 1.6’s, and 2 were
1999-2005 cars.
Buying
Buying is ALWAYS cheaper. If this is your first race
car and you are not sure how much you will enjoy the sport then I would suggest
buying an existing proven race car. You can get great deals on existing
cars and can pretty much hit the track right away. Prior to looking at
any used race car make sure you understand the rules (GCR) in depth.
Bring a GCR with you and if you are not sure of something the owner is telling
you, ask them show you in the GCR where it is legal. This goes not only
for the Spec Miata specific ruleset, but also the cage design rules and rules
regarding graphic size and placement.
When you are looking at buying a used car remember, there is
always a reason why a person is selling their race car, and you should know why
the seller is selling theirs. SM is the fastest growing class in SCCA and
is one of the most economical classes to run. Are they getting out of
racing? Are they changing classes? Are they building themselves a
new car?
Generally speaking, you should never buy a race car sight
unseen. Buy something within driving distance so that you can go look at
the car multiple times if need be. Try to see at least 2 cars so that you
have something to compare against. History on an existing race car is
very important. The owner should be able to provide you with race results
for the previous season or sometimes they can be found online for each
region. DNS and DNF’s are very rare in these cars so make sure and
investigate the history of the car. Look to the more experienced racers
in your region, as they can probably tell you about the car from having raced
with it. The vehicles’ log book will also tell you about significant
damage, so make sure to look at it along with the vehicle.
When you are buying a used car make sure to look at several
of the key components and the maintenance schedule the current owner is on for
replacement or rebuilding. Hubs, brake calipers, transmission,
differential, and drive shaft are all items that MUST be rebuilt on a timely
schedule. They can and will all produce drag and friction and if not
properly serviced or replaced, they will cause your car to be slower than ones
that are serviced. The current owner should be able to provide you with a
maintenance listing of what parts are in the car and when they were last
serviced or rebuilt either by the odometer reading, or off of an hour
meter.
Utilize your more experienced racers in the region.
They are great resources and will be happy to help. There is nothing
wrong with buying a used race car as long as you know what you are
buying. No matter what level or preparation or quality of car, as long as
it is safe you will always have somewhere to run and plenty of people to race
with.
Current market value on a used “regional” Spec Miata is
anywhere from $10,000 to $18,000.00. Nationally prepared cars with a
significant spares package can go much higher.
What tools should I take with me when going to look at a Spec Miata?
- Helmet. – So you can see how you fit in the car with the
cage.
- Magnifying Glass – To inspect welds.
- Towel or rubber mat – So you can get down on the ground to
get a good look under the car.
- Jack – So you can jack up the car to look underneath.
- Flashlight
- GCR
- Digital Camera – Take pictures so you can review the car
later during your decision making process.
What should I look for when buying a used Spec Miata?
- Chassis
- Frame Rails – Get under the car and look at the frame
rails. Look for signs of a significant impact, or severe damage.
The frame rails should be as straight as possible. Most of these
cars that have been turned into race cars will have collapsed frame rails
from someone trying to jack up the car on them. Don’t worry too
much about this as it doesn’t really hurt the car too much. At some
of the rougher tracks around these cars will bottom out off of the FIA
curbing and turn exit, so there can be slight damage to the frame rails
from this as well.
- Front Sub Frame – Investigate the front sub frame and
look for signs of it being bottomed out. The sub frame is what all
your front suspension settings are driven off of, so a sub frame with
damage will impact your ability to set up the car appropriately.
- Camber bolts – Look at the camber bolts and make a mental
note of where they are. Are both sides set the same, or are they in
out of phase with one another? Typically if the bolts are not in
the same place on each side, it is a sign that something is bent.
It could just be the aluminum control arm bolts (very cheap) or it could
be the control arms.
- Log Book – Look at the logbook as it should have
notations from an SCCA steward about any significant damage that occurred
during a race weekend. Its important to note that damage can occur
on test days and other non SCCA sanctioned race weekends.
- Body
- Engine Bay – Look at all the sheet metal in the front of
the car. Look around under the headlight assembly to see signs of
impact. Also look at the where the upper chassis meets the
firewall. If the car had significant front end damage, it is hard
to hide it at the firewall area especially under the brake master
cylinder. Most of these cars by now have had some contact either as
a street car or in their racing life. Minor damage in the front is
ok, you just need to know that the repairs were done properly and what
you are actually buying.
- Trunk – Look in the trunk for signs of a big
impact. If the car has had a substantial rear impact, the rear
bumper support will show signs of the impact.
- Motor/Running Gear
- Differential – What diff is in it? Now that 1.6’s
can use the 1.8 Torsen, you need to correctly identify which diff is in
the car. If the car has an open diff, then you will be looking at
roughly $1,000.00 to convert to the Mazda Comp differential.
- Compression test – A Compression test will give you a
good idea of the general condition of the engine. You want to look
for compression numbers with a minimum of roughly 180 with a consistent
reading across the board. Compression lower than 180 is probably ok
if it is consistent from cylinder to cylinder, but you may be down on
horsepower compared to the front running cars. Front running cars
will be around 200 as a reference point (but compression gauges don’t all
read the same). The key here is a consistent reading and using the
gauge correctly. When performing the compression test
you will want to first bring the motor up to operating temperature. Once
up to operating temperature you will want to disconnect the coil pack
remove all 4 spark plugs. Then crank over the motor until the gauge
stops raising with throttle wide open.
- Leak Down – The leak down test is a little more accurate
assessment of the condition of the motor that will require special
tools. What you should be looking for is a number that is ideally
5% or less. A high mileage street car may come in around 10% which
isn’t necessarily something to be afraid of, it just isn’t at its peak
performance. Any leak down issues with these motors are easily fixable
in the rebuilding process.
- Transmission – Make sure the transmission shifts easily
into each gear. You can jack the car up and shift through the gears
with the motor running to test it. These transmissions are rock
solid and usually last a long time. Replacement or spare
transmissions can be found at junk yards across the country for not much
money.
- Roll Cage
- Design - Look at the roll cage design. Take
your helmet with you when you go to look at a used race car. Is it
updated to the latest (Dual Nascar Bars) rules? Do you comfortably
fit in the car? Is your elbow away from the upper Nascar bar?
Is your head far enough below the main hoop? Where does the forward
down tube land? Can you use the stock dead pedal, and how will that
tube play a part in an accident?
- Welds – Investigate the welds with a magnifying
glass to look for cracks. Painted roll cages make it easy to
identify cracks if the car has been in a big accident. Also make
sure that the welds are 360 degrees around the tubes. Run your
finger around those tight weld joints and use a flashlight to look at all
weld joints to ensure they go all the way around the tube.
- Legality/Material construction - Make sure that
there are inspection holes in each one of the primary tubes in the car so
you can check for appropriate wall thickness and material. Refer to
section 9.4.2 in your GCR, or go online and you can view the roll cage
requirements @ http://www.scca.org/_FileLibrary/File/GCR2007.pdf.
There are some builders using obscure sized tubing and some of the early
cars are using .120 wall cages which can weigh as much as 25lbs more than
the allowed 1 ½ x .095 DOM. Keep resale in mind here as well.
How will your cage help or hurt your cars resale value? What if a
tall or big person wants to buy your car, will the design and weight be
an issue for them?
Building a car
If you have race experience and are moving into the class, or
are particular about your car then building a car has a lot of benefit.
Primarily you know what is in the car and will more than likely avoid
repair/replacement work at the track on race weekends.
Roll cages are part of our business and I can not stress
enough the importance of a good safe cage made out of the appropriate size and
material that fits you and gives you the maximum amount of room in the
car. By building a car you can ensure that the proper cage for your car
and body type will happen. This will not only make you safer in the car,
but will also help the resale value should you ever to decide to sell the car.
The beauty of building a car is that there are no
surprises. You know what is in the vehicle and have a blank slate to
start your maintenance and replacement schedule. In most regions the
championship is a tightly contested battle that will come down to the last race
of the year. Missing one race and having a DNF from a “surprise” is
enough to cost you a championship.
You can expect at least $15,000.00 to build a new car, if
you are doing a lot of the work. A very nicely built “regional” car can
be done for under $20,000.00.
Preparation
Whether you build of buy, preparation plays a large part in
how fast you will go. These cars are low horsepower cars and every little
bit helps. 3 Horsepower in the class is huge! Rebuilt hubs, brakes
new drive shaft, all of these things can add friction and rolling resistance to
the car and add up, so be realistic with your goals based on the car you buy or
build.
Some guys align their car every race, and some do it once a
year. Ask around and watch, and by the end of the season with the right
tools you can be doing your own alignments and preparation.
More on this topic later…..
Summary
The best part about this class if the people that make it
up. Go to one of the races in your region and you will find very
knowledgeable friendly people who are willing to help and welcome you into the
sport. No matter what level of car you buy or build and no matter how
fast or slow you may be, you will always have a fun and safe environment and
other like minded people to race with.
Look for more articles soon on the following topics:
- Spares and Tools – What spares and tools should I take to the
track to make my life easier?
- Race Budget – What type of costs should I expect to race
my car.
- First Race – What gear will I need and what can I expect
for my first race weekend?
Sean Hedrick
www.miatacage.com
Oregion Region SCCA