Club GP
FAQ
By Jason Penneman
Q. How can I join a local chapter of ClubGP?
A. To join your local
chapter or find one nearest to you, visit: http://www.clubgp.com/clubgp/
Q. Where can I purchase performance and factory replacement parts for my Grand Prix or other W-body vehicle?
A. There are many vendors who sale performance parts and accessories for the Grand Prix and other W-body vehicles. Some of these vendors are:
www.americansportscardesigns.com
Also, the standard performance parts manufacturers such as Jeg’s and Summit Racing carry parts and accessories that many of us use.
Q. What does “GTP” stand for?
A. The short answer: Grand Touring Prototype. It was an American road racing class at the
time the GTP model was introduced.
Q. What are the differences between the model years on
the Grand Prix GTP?
A. ZZPerformance has compiled a very good list of the changes between model years on the Grand Prix GTP here:
http://www.zzperformance.com/zzp/info/info_model_changes.htm
Q. I am new and my car is in stock form, what should my
first mods be?
A. This answer all depends on what you are looking for... handling, or horsepower. Typically the first few mods for a GTP that will yield noticeable gains are:
-3.4” SC Pulley
-180 degree thermostat
-Cold air intake
All of the above can be had for less than $200 altogether and will yield about a 20hp gain at the wheels. Exhaust mods usually follow and are recommended to minimize Knock Retard, or KR (mentioned later in this document).
The usual first mods for a GT or other NA 3.8 Liter are:
-High Velocity Throttle Body
-Cold air intake
-High ratio rockers
Q. Can I put a supercharger from a GTP on my GT?
A. Simply put, No. The GTP engine is lower compression than
that of the GT and contains a few other “tweaks” to run the supercharger effectively
and reliably. This includes a different throttle body, fuel rails, PCM
(computer), transmission, etc.
Q. Are the 2004+ models available in a coupe (2-door)
version?
A. At the time of this writing, no. GM decided to do away with the coupe for the 2003+ model years because more people were buying 4 doors (sedans) and they wanted to take advantage of this market. To satisfy customers who wanted a 2-door version, GM directed them to the new Chevy Monte Carlo SS (supercharged 3.8L engine) and Pontiac GTO.
Q. What are the various engine designations/codes?
A. L67 – Series II GTP (‘97-’03 Grand Prix GTP, 2004
Monte Carlo SS/Impala SS, Regal GS, Bonneville SSEi)
L36 –
Series II GT (’97-’03
Grand Prix GT, 2002-’03 Monte Carlo SS/Impala, Regal LS, Oldsmobile Intrigue,
Bonneville)
L32 –
Series III GTP (2004+
Grand Prix GTP and GTP Comp G)
L26 – Series III GT (2004+ Grand Prix GT1 and GT2)
Q. What mods do I need to run a 13.9x in the ¼ mile in my
GTP?
A. To run a 13.9x at a ¼ mile drag strip assuming ideal weather conditions (30-50 degrees, low humidity, low altitude, etc), you would typically need at least the following:
-3.4” Supercharger Pulley
-Cold air intake
-Light exhaust mods (3” downpipe and u-bend removal)
-1 heat range cooler spark plugs than stock
-A sub 2.2 60 foot time, ie., a good launch
Some cars do it with less, and some take more. You can also substitute some mods for others, such as rockers instead of exhaust work. Every car runs different so these mods represent what is required for the majority of us to run sub 14’s.
Q. Should I use a Transmission Cooler? Will it prolong the life of my transmission?
A. This topic has been debated at great length over the past few years. A general consensus is that if nothing else, the cooler helps prolong the life of the fluid. At high temperatures (above about 220 F), most transmission fluid begins to break down and does not do its job properly. This fact alone can save you hundreds of dollars in frequent fluid changes. Also, if the fluid avoids breakdown, the life of certain components of the transmission will be extended. For some in cooler climates, the transmission never reaches these temperatures so the fluid will do its job longer, but for those in warmer climates, keeping the transmission fluid from breaking down is a valid reason to install a cooler.
Q. What do I need to do to make my car run a xx.xx in the
¼ mile?
A. Probably one of the most sought-after questions. Luckily, INTENSE™ racing has provided a general list of what mods will get you the times you want:
http://www.intense-racing.com/recipes.html
Q. How do I calculate my ¼ mile time from 1/8 mile and
vice-versa?
A. To convert your 1/8 mile time to ¼ mile, multiply your 1/8 mile time by approximately 1.553. This will give you a very close estimate of what you would run in the ¼ mile.
Q. How do I update my ¼ mile time on the ClubGP website?
A. http://www.clubgp.com/cgi-asp/qtrmilefaq.asp
Q. Can I use 87 octane in my GTP?
A. As the owner’s manual states, you should not use less than premium fuel in a GTP or other supercharged 3.8L engine. Higher octane fuel prevents Knock Retard and loss of power.
Q. What is “Auto-Tap”?
A. Auto Tap is a diagnostic scan tool for ODBII compliant vehicles such as the Grand Prix and other GM vehicles since 1996. Connecting an Auto-Tap to your vehicle will allow you to view most of the car’s recorded parameters (Knock, misfires, RPMs, speed, air/fuel ratio, etc.). This allows you to determine how well your car is running and is especially useful after performing modifications to the engine. More information can be found at: www.autotap.com
Q. I have a Service Engine Soon (SES) light. What do I do?
A. Find someone in your area with a
Scan tool (Auto-Tap, LS1 tool, etc.) that they can hook up to read the codes
from the cars computer. This can be done for free at most parts stores as well.
Q. What are all of the abbreviations and acronyms on the
message forum?
A. We use lots of different abbreviations on the message forum to save time typing commonly used phrases and names. Some of these are…
Conversation:
DIY – Do-it-yourself (such as DIY car wash)
FWIW – For what its worth
FYI – For your information
IIRC – If I recall correctly
LOL – Laugh out loud
N/A – Not applicable (sometimes also used for Naturally Aspirated)
ROTFL – Rolling on the floor laughing
ROTFLMAO – Rolling on the floor laughing my a$$ off
TIA – Thanks in advance
WTF – What the ****?
Car parts:
CAI – Cold Air Intake
DIC – Driver’s information center (The readout above the center AC vents)
DP – Downpipe
FWI – Fenderwell Intake
KR – Knock Retard
NA or N/A– Naturally Aspirated (no supercharger or turbocharger)
PCM – Powertrain Control Module (The car’s computer)
SC – Supercharger
SS IC - ZZP's Short Stack Intercooler
TB - Throttle Body
HVTB - High Velocity Throttle Body
T-stat - Thermostat
A more extensive list of acronyms is available at: http://www.clubgp.com/newforum/tm.asp?m=194709
Q. Can I reset the range (miles left before running out
of gas) when it reads “LOW” on the Driver’s Info. Center?
A. Yes. To reset the Range, hold the “Reset” button down until the range resets.
Q. What is a QTEC or exhaust cutout?
A. An exhaust cutout is a short Y-pipe that is welded into the stock exhaust. There is a cap on one end that is usually held in place with 3 wing nuts. This makes for easy removal at the track or any time you would want to bypass a section of your exhaust, such as the mufflers or catalytic converter. A QTEC takes further advantage of this by adding an electric motor to open a valve to let the exhaust out of the cutout, which is controlled through a switch mounted somewhere inside the car. There are a few different makers of these electric exhaust cutouts and are available through some of the vendors noted above.
Q. Can a GTP run without the supercharger belt?
A. Yes. Since the supercharger belt doesn’t run anything else other than the supercharger, a GTP will run without the supercharger belt.
Q. Is a larger oil filter beneficial? What is the part number for a larger oil filter?
A. Yes, most people would agree that a larger oil filter would be more effective at filtering the oil and most of us run larger filters. There are a few options when choosing a brand of oil filter. The AC Delco filter part number for a longer filter is PF-52. The Mobil 1* brand of oil filter for the same length is M1-201.
*When purchasing the Mobil M1-201 filter, be sure and verify the contents of the box first. Some people will swap the filters into a different box before buying to get the Mobil 1 filter at a better price, so it’s always a good idea to check.
Q. Is there a parts list for all of the parts on my car?
A. There is a searchable parts list available on the ClubGP home page at:
http://www.clubgp.com/cgi-asp/partslist.asp
There is also a scanned copy of a Grand Prix parts list in .pdf format (~6MB) at:
http://www.clubgp.com/97-02_GP_Parts_List.pdf
Q. What is KR, or Knock Retard?
A. Simply put, Knock Retard is the retarding of timing by the PCM as a result of the PCM detecting the early stages of detonation in the engine. For more in-depth information on KR, refer to this article by Bill Hooper:
http://www.zzperformance.com/zzp/info/knock_retard/kr_about.htm
Q. What is “resetting” the PCM and how do I do it?
A. Resetting the PCM is a process that takes the PCM into learning mode. This is usually recommended any time you make a modification to the engine or add race gas. Resetting the PCM also resets all of the Driver’s Info. Center numbers, except Oil Life.
To reset the PCM:
1. Disconnect (unscrew) the negative terminal on the car’s battery
2. Wait 30 minutes
3. Reconnect the negative terminal
4. Start car (usually won’t start the first try after a reset)
Q. What gains can I expect from ______ modification?
A. One of the Michigan chapters of ClubGP has compiled a great website describing the gains of the most common performance modifications:
http://www.migpc.com/Modifications/modifications.html
Q. Where can I go for more technical information and
How-To’s?
A. The ClubGP home page, many club chapter websites across the country, and vendors, have compiled some great information and instructions for almost every mod that is out there. Here are links to some great sources of information:
ClubGP Upgrades Page – A page on the ClubGP site dedicated to write-ups and instructions on upgrades and maintenance:
http://www.clubgp.com/cgi-asp/mods.asp
ClubGP FAQs – FAQs put together by members and posted on the message forum. These include most of the torque specs for the L67 and L36 and other useful knowledge:
http://www.clubgp.com/newforum/tt.asp?appid=14
TACGP “How-To” page – A detailed list of links for how to perform almost every modification that is out there: http://tacgp.clubgp.com/custom_mods/index.html
MIGPC Modifications page – Describes common mods and expected gains:
http://www.migpc.com/Modifications/modifications.html