|Technical Frequently Asked Questions|
|The focus of this is for cost effective upgrades for primarily street driven cars, so some of the recommendations might be on the conservative side. This is a "work in progress" and will be changing as products evolve, we learn about new things, and people contribute knowledge. To have something added to this FAQ, please email Ken Mosher at: firstname.lastname@example.org
I know I'm biased towards fast street car setups (I'm a big Red Armstrong fan), so I know that my own biases show thru in places, so if it isn't appropriate, let me know. As far as disclaimers go I have no connection with Red Armstrong or Quad Air, other than an admirer and believer in his approach I have no connection with Bowling Green Customs, Dennis Kirban, Torque Technologies or Kenne-Bell. I have a connection with ATR as an occasional small time distributor of their products ... although, I think I'm fairly unbiased. I produce TurboLink(tm).
|What kind of slicks should I use at the track?|
|Depending on the power level of the car and the way the car launches, this can vary. Generally speaking, you should try to get slicks that are smaller so that you don't have to pull so much rolling resistance.
I have experience with the 26"x10"x15" and their 26"x8.5"x15" slicks. The 8.5" (baby) Mickeys work very well on a high 12 car, since you can run a little more air pressure. The 10" slicks are necessary when you start making more power and start shocking the tires a little harder on the launch. The 10" slicks should be mounted on 8" rims, while you can use a 7" rim with the baby Mickeys. I find that you need to heat them pretty good to get consistent sixty foot results, especially on a track that is not well prepped. Eventually, you may start needing the 28" tall M/Ts to keep from running out of RPMs in 3rd gear through the traps. The 28"x9" slick will work well on 8" rims without notching the frame. The killer setup is 28"x10.5" M/Ts, but it requires notching the frame or rolling the fenderlip (depending on wheel offset). The 28"x9" tire will fit on an 8" rim and fit inthe wheelwell without frame notching.
Many people report good results with their DOT compound tires that are available in a various sizes and a couple of rubber compounds. They won't work as well as a slick (expect mid 1.7 short times), but are a good street/strip tire. The Hoosier slicks come in various sizes and seem to provide a little rounder sidewall profile and a tiny bit more tread area on the ground than the M/Ts of similar sizes.
Firestone makes a 26"x9"x15" slick that seems to work pretty well. They don't seem to need as much of a burnout as the Mickeys and as a consequence may last a bit longer. I have not seen these used on anything other than a mid 12 car that is going 1.67-1.70 60 foot times.
|What About Sticky Street Tires?|
|There are several good street tires out there now. Everything from recaps to very good radials. Be aware though, the tires discussed below will not have great wear characteristics, due to their sticky consistency.
B.F. Goodrich Drag Radials
These tires are available in several sizes, including P275/50-15s and P245/50-16s. They look like a normal Comp T/A radial, but they have a wrinkle wall side construction that makes them hook very well. They also have a tendancy to keep grabbing, even when spinning (as opposed to just going up in smoke). I personally saw Red's wife's car rip of some low 1.6 sixty foot times (and a 1.58) with these tires at Bowling Green. The track was hooking pretty well, but still very impressive for a street tire. Very sneaky.
These are bias ply tires that are almost slicks. They have little grooves cut in them (tread), and are D.O.T. rated. They seem to work pretty well, but like a lot of heat in them to really get them to work on the street. They are about the same price as the Drag Radials. They are available in a variety of sizes.
Hoosier Quick Times
Scott Keller, the list moderator, used these tires to good advantage on his car. They were good for mid/high 1.7s on his Recipe T-Type. Other people use these tires to good advantage. They have a rounded shoulder, like a radial and dirt track type tread that sometimes can "howl" a bit on concrete surfaces. They wear very quickly, but are cheaper than most any other D.O.T. rated tire.
Nitto Drag Radials
These tires are available in several sizes, including P275/50-15s and P245/50-16s. They are in use by many people and provide excellent street/strip traction. Their primary advantage may lie in the fact that they are of radial construction and offer superior wear compared to the BFG Drag Radials.
|My car has now reached the mid/low 13s and indications point to needing an upgrade to my fuel delivery system. What should I go with?|
|As with all other items, how much fuel do you need? Are you planning on just going 12s and no further? 11s? 10s? Based on your needs the following are recommended:
Often times it will become necessary to replace the stock pump due to a collapsed sock or just plain wear. Even if the car is going to remain relatively stock, it can benefit from a pump upgrade.
Red Armstrong's XP Pump
This pump is highly recommended and can be effective well into the 11s with Red's Fuel Enhancer or Volt Booster. Chuck Strader is successfully using this pump to go 10.90s@123+ thru the full exhaust system. This pump is modified by Red to provide greater pressure and flow than the stock pump and replaces the in-tank pump.
An adjustable regulator is recommended to compensate for the increased fuel delivery and to aid in tuning.
Red Armstrong's Double XP Pumper
This system can be effective well into the 10s and should be considered if your car is in the low 11s. This setup incorporates two XP pumps on your stock hanger. The second pump is staged with a Hobbs switch to turn on at about 10 psi of boost. This arrangement results in a very high volume setup.
The volume can make tuning difficult, especially in lower HP cars. Small adjustments can result in big changes. Needs additional wiring. If the staging isn't set up right, you may end up with a staggered fuel curve. Possibilty of "flooding the regulator", exceeding it's capacity to adjust without using enlarged fuel lines. An adjustable regulator is absolutely required to compensate for the increased fuel delivery and to aid in tuning.
Modern Muscle's in-tank pumps
Modern Muscle sells a line of inline pumps that are similar in performance and price to the XP pump. They offer several solutions that have the same benefits as the XP pump.
An adjustable regulator is recommended to compensate for the increased fuel delivery and to aid in tuning.
Syclone/Turbo T/A or Supercharged Park Avenue pump
This is an upgraded pump used in the Syclone/Typhoons and Turbo T/A. It provides more pressure and flow than the stock pump.
This is an intank pump that dramatically increases fuel capacity. These pumps will supply plenty of fuel for a 10 second full weight car.
An adjustable regulator is recommended to compensate for the increased fuel delivery and to aid in tuning.
External Bosch 287 Puller Pump
This alternative involves mounting an external pump and pulling the fuel thru the stock in-tank pump. It delivers higher pressure and lots of volume.
ATR Double Pumper System
This alternative involves replaces the in-tank pump with dual pumps feeding through a billet "Y" into the fuel line. It delivers higher pressure and lots of volume. It is available with a "staged" setup to run just one pump until extra fuel is needed.
Adjustable regulators are highly recommended for tuning purposes. Several adjustable regulators are available. ATR and CPP both sell a similar style black regulator that consists of a stock bottom with a billet top and an adjustment screw. Kenne-Bell sells a nonstock billet replacement that is blue anodized. Bowling Green Customs sells a very sneaky stock appearing regulator that is adjusted via a set screw hidden in the vacuum port. The Accufab unit (same as the Kenne-Bell, Modern Muscle unit) is a billet piece.
The old standby is the "237" regulator from the Sommerset Regal. This is essentially a squeezed "233" (stock) regulator to provide a few more pounds of fuel pressure.
|There are so many chips out there... which one should I use?|
|This can depend on lots of variables. Chips that are great for racing with leaded racing gas might be totally unsuited to street driving. The combination you are using can affect the type of chip you should use as well.
ATR's PitBull and Strip Chip
These chips seem to have good temperature control and the PitBull seems to be very driveable on the street. It is aggressive with the boost and timing, so you may have to adjust your wastegate to compensate if the car doesn't like the boost. The Strip Chip is a good race chip and fairly conservative. It tends to run a bit on the rich side and locks the TCC in 3rd gear. Both chips are good for stock injector cars with enhanced fuel systems and adjustable pressure regulators. They both drop the boost about a pound in top gear to avoid overboosting. The Strip Chip used to be available with minor tweaks for injectors/regulators/etc by asking for a special chip. They may not do this any longer.
Red Armstrong's 93, 100, 107,108 chips
Red's chips have evolved as he has learned different things about his combination. The 93 is a nice mild street chip with good temperature control and very little timing. The 100 is a little more aggressive and requires 100 octane gas. The 108 requires 108 octane gas (at least) and is his full out race chip. Each chip can be had with different parameters. Red has customized versions depending on the types of injectors you are running and your fuel system. Works best on cars running combinations similar to Red's (XP pump etc.) Chuck has successfully used several versions of Red's chips in all his cars and swears by them. I often get to use his "hand me downs" and I like them. I'm currently running his 107 chips for 009 injectors and the double pumper.
Conley Performance Plus mini-Mag and Magnum
Any feedback is appreciated here ... the last chip I tried was several years ago (Mag IV). It was pretty aggressive for the time. It also didn't lock the TCC. How 'bout an update?
Jay Carter's Chips
I like a lot of the things he is trying, since the car idles nicer and has improved the cold start performance. His approach of reducing the total timing and running more boost seems to be effective. I haven't had a chance to try one of his chips at the track yet. He seems to really have a handle on blue top and 009 injector fuel characteristics. Many list members are very happy with his efforts.
MMC makes a series of street oriented chips, called the Street Plus 11 and a set of race oriented chips, called the Terminator series. MMC is very good about tailoring a chip to your combination, based on their standard chips. Prices are very reasonable. Modern Muscle has pioneered some unique features in some of their chips, including extended range MAF values for use with their MAF Translator, and custom ALDL data streams for use with their ScanMaster.
Kenne-Bell HotFlash chips
Feedback needed here. I know several people are running them with good results . From what they tell me, they seem to like lots of boost and add very little timing.
Check out their Web Page for complete information on these unique chips. I've run one at the track and although I really didn't see any major increase in performance, I did notice very nice driveability characteristics off the track.
Several versions of thumbwheel chips are available with a variety of programming. Some are used for open loop programs for use with a gutted MAF and others offer a variety of more standard programs. The basic advantage of these chips are the fact that you can choose different settings with a thumbwheel. This is accomplished by burning several chips into one larger capacity chip. The thumbwheel then selects the chip program to be used. Most of the aftermarket vendors offer a version of the thumbwheel chip with their own design chip programming burned in.
|I like the idea of a bigger/better downpipe. What should I use?|
|There are basically three types of downpipe available:
Kenne-Bell 3" Downpipe
This downpipe is in category 1 and replaces the stock downpipe and uses a (modified) stock housing. It fits under the stock turbo shield and is made of mild steel. A 3" cat. converter or test pipe is needed to mate to the exhaust system.
This downpipe is in category 2. It is a mild steel unit that replaces the stock housing, but has an integral wastegate flapper. It was used on the 1993 GS Nationals Project car and worked well. The turbo shield must be cut to retain the shield. A 3" cat. converter or test pipe is needed to mate to the exhaust system.
This downpipe is in category 1-2. I say this because they replace the stock housing with a new cast iron housing with an integral flapper. The bigger downpipe bolts to this. Everything fits under the stock turbo shield. A 3" cat. converter or test pipe is needed to mate to the exhaust system. Early versions didn't work with headers, but later versions are said to be made to fit with headers.
ATR Stainless Steel 2 3/4" downpipe.
This pipe is in category 1. It is a simple replacement for the stock downpipe. It is slightly larger than the stock pipe and should be used with a bigger lead ring seal.
ATR Stainless Steel 3" downpipe
This pipe is in category 3. It requires the turbo shield to be notched for the wastegate and the pipe. It is designed to use a single wastegate and dumps the wastegate output back into the exhaust system. If the ATR wastegate is used, only 1 wastegate is required, although the turbo wastegate hole should be enlarged and matched to the downpipe flange. A Delta Gate adapter is available. A 3" cat converter or test pipe is required.
This pipe is also in category 3. It is a thermal coated 2 3/4" pipe that requires an external wastegate. Delta Gates are commonly used in conjunction with this pipe. It requires notching the turbo shield for the pipe, and sometimes for the wastegate, depending on which wastegate is used. The wastegate output is piped back into the exhaust. A second wastegate in the crossover pipe is sometimes required to get good boost control.
Terry Houston Downpipe
This pipe is an overwhelming favorite with most people running a street combination (although versions of this pipe have been deep into the 10s). It retains the stock wastegate actuator setup and replaces the stock elbox. It is mandrel bent, stainless steel and has a nice smooth set of curves to allow for maximum flow.
|I'm ready to upgrade my exhaust system. What's out there?|
|Many exhaust systems are available now. You have to decide on your price range, whether you think stainless steel is necessary, noise level, performance level, etc.
Kirban sells a variety of exhaust systems. Some require the "Y" pipe from your old system to be reused. He has a GNX replica system. Prices range in the $300-500 range. He is working on a new stainless steel system that will be in the $700 range.
ATR makes several exhaust systems. Two of the best are 2 1/2" and stainless mandrel bent tubing. One uses the Walker Ultra Flow mufflers (or their equivalent PitBull mufflers) and is their top of the line. The mufflers are very free flowing, yet provide excellent sound control. They have a throaty rumble, but don't resonate like the Dynomaxs. The price is around $700. The other system is also mandrel bent, but uses the Dynomax SuperTurbo mufflers. These mufflers sometimes tend to resonate at certain frequencies at cruise, but some people like that. They work very well and were considered state of the art a year or two ago. System price is around $500. They also make a single 3" exhaust system that uses a 3" UltraFlow style muffler in place of where the catalytic converter. This is a light system, stainless steel, and has a unique sound (I personally prefer the sound of the duals).
This mild steel system is a 2 3/4"-3" system that uses the Dynomax Super Turbo mufflers. They system is complete, including the "Y" pipe. It runs about $400.
Kenne-Bell 3" single system
The advantage of this system is the weight savings. The single pipe system is easier to route and is lighter. The system uses a single Walker Ultra Flow muffler (round). The system is mild steel and design to be used with the K-B 3" downpipe. Price is in the $400 range.
ATR 3" Single Shot system
The advantage of this system is (again) the weight savings. The single pipe system is easier to route and is lighter. The system uses a single PitBull muffler in front of the axle. The system is Stainless Steel and mandrel bent. These types of exhausts are typically louder and have a more "raspy" tone than the dual systems. Price is in the $400 range.
Hooker Super Flow system
This system is a mild steel system that is a complete cat back dual muffler system for a very reasonable price (About $300 from mail order sources like Jeg's or Summit). Early systems were prone to corrosion and the infamous drone at 2000 RPM, but the later version seems to be better quality.
|When do I need to start upgrading my injectors?|
|This is a controversial subject. If your stock injectors are worn or leaking, it is smart to replace them with injectors that will prepare you for the "next step". As a rule of thumb, you can go low 12s without replacing injectors. High 11s are not uncommon with stock injectors.... however, it is often desirable to change injectors at this point just from a tunability stand point, since you can turn the fuel pressure down with bigger injectors.
Blue Top Injectors
Several vendors sell these pintle style injectors in the $250-$300 range. These injectors provide a nice linear response to fuel pressure and can be used without a special chip. A chip tuned for these injectors can be even more effective. Red Armstrong has flowed these and likes the spray pattern and response to fuel pressure according to a recent article in the GS X-tra (See the GSCA Club). These are the new hot ticket for high flow injectors and should be good for well into the 11s.
Several vendors also offer these injectors in the $300 range. These are also referred to as 40# injectors and are the disc type. They work well if you have a special chip tuned for their characteristics ... they have a tendancy to be rich on the bottom end when fuel pressures are tuned to allow for enough fuel delivery on the top end. They are tough to get to lean out on the bottom end, but can be made to work. These were the hot ticket up until the Blue Tops. They work into the 10s and work best on mid 11 tuned cars.
Green Stripe Injectors
These are relatives of the Red Stripes and flow slightly more than stock (30# vs. 28#). They are also disc type injectors and can result in a smoother idle than stock. No real performance increase can be expected, but they make nice stock replacements.
Lucas "009" Injectors
These injectors are more linear than the Red Stripes and actually seem to result in a smoother idle than the Red Stripes. They are rated at ~43lbs/hr and are good for high 10/mid 11 cars. They work best with bigger turbos, such as the TA/TE62 and TE63. These require a chip with the injector constant set correctly for these injectors. Jay Carter seems to be very successful with specially modified chips to exploit the characteristics of these injectors.
|How do I tune one of these cars? Do I need a scan tool? What scan tools are popular?|
|There are several alternatives for this. The only way to get a clear idea of what the car is doing is to have one of these tools.
This is a package that runs on most laptop/desktop PCs and hooks up to the ALDL port with the supplied cables and displays the ECM data stream in real time. There is a growing user base for this tool, and the file format is easy to exchange with others who have the tool. Data can also be exchanged using the common CSV file format and viewed in spreadsheets and word processors. You have the choice of displaying the data in real time in either a numeric fashion, which shows all the parameters and flags simultaneously, or a graphical format, which shows key performance indicators and flags in bar graph style display with round guages for RPM and Vehicle Speed. V2.0+ supports display and recording of boost with an optional boost sensing kit. TurboLink(tm) allows you to save data to disk, export it to CSV or ASCII files, and print the data. You can review the data in either display mode. V2.0+ supports '84-87 Turbo Regals, '89 Turbo T/As, VIN 3 Buick, Olds, Pontiacs, and '84-8 Turbo Rivieras. Cost is $149.95 and is available from email@example.com. Click here for the TurboLink(tm) Web Page.
The OTC 2000 is a small box (approx 10"x 5" wide by 2" deep) with a single line LED display and a keypad that plugs into the under dash ALDL plug and reads the ECM data stream. You plug a cartridge in the bottom that is compatible with the '87 cars (some work with Ford/GM/Chrysler and some add recording capabilities). Different data items can be displayed on the display by scrolling one set of two items at a time. The 4000 is similar, except it is a little bigger and has an LED screen with 4 lines of display and can display more than 2 parameters at a time (unlike the 2000). These are sometimes sold locally from different places like body shops and repair places for $175-$300 for a 2000 and $300-800 for a 4000. The GSCA is able to occaisonally get the 4000s for a deeply discounted price (~$500). Pretty hard to find any more, but persistance can pay off.
This program also runs on a PC and hooks up to the ALDL connector to display the ECM data stream. It supports disk saves, several models and years of GM cars, and printing the data. The Diacom has a few bugs in the data for the Turbo Regals, but works very well as a overall diagnostic device that supports several models of GM cars. Price is around $300 for the basic package and around $600 for professional package.
|I need to replace my turbocharger, or I want to replace my turbocharger with an upgraded unit. What should I consider?|
|Again, this depends. Stock rebuilt turbos are available from GM for around $500, so if you are just looking to replace a dead stock unit and don't think you want to someday try to go very fast, this may be the right avenue. As far replacement turbos go, the following are commonly used:
These are turbos that replace the stock center section with one using bigger compressor and turbine wheels and generally designated with a "TA" prefix. The stock compressor and turbine housings are machined to accept these larger wheels, which results in much greater flow capacity and less exhaust back pressure. These are sold as Stage IIIA, TA49, Cheetah Stage IIIA, etc. and cost around $800.
These are turbos that replace the stock center section with one using bigger compressor and turbine wheels and also use a slightly bigger compressor housing. These have a slightly greater flow than the stock appearing variety. They can be had with either the 0.63 or the 0.82 turbine housing.
These turbos are still stock appearing, but have stuffed the wheels from a 60-1 in them. These can be worth 20-25 HP over the other stock appearing variations.The TA62 has a cut down P trim exhaust wheel, and the TA60 has the same wheel as the TA49.
These turbos are hybrid turbos much like the TA series, but they are stock appearing. These have a slightly different compressor design that can contribute a few more HP than the stock appearing style. These can be worth 25-30 HP over the stock turbo.
Advantages: These turbos generally much greater performance at the top end. They also provide a basis for performance well into the the 10s.
These are the biggest 3 bolt turbos available at the time of this writing. They benefit from a 9" high stall converter and need plenty of fuel and head work to make them work to the best advantage. These are best left to mid 10 and quicker cars with pretty heavy modifications.
Stage II Turbos
These turbos used to be the first step of upgrade for stock cars. No longer really used. Required a converter to work. Used the stock turbine, but upgraded the compressor side. The stock appearing are about the same price and perform better overall. Basically, these are considered "old technology" and the newer units all outperform it in price and performance.
|I think I want to upgrade my intercooler. What should I consider?|
|As with anything, cost vs. gain is a consideration. If you have a totally stock car, the intercooler isn't going to be a very effective way to spend money. When the car starts going low 12s, you probably want to consider your next step. Keep in mind that my car has gone 11.50s with a totally stock intercooler.
Modified intercooler neck
This is a recent innovation that removes the restriction from the intercooler inlet tube by replacing it with a smooth radius, bigger neck. It is a fairly subtle modification and will definitely help a car that is flowing alot of air. It seems to complement modified turbo, ported head cars very nicely. It won't hurt a stock/mild car, but it may not provide much performance increase.
Extended Stock intercooler
This is basically a stock intercooler with half of another intercooler welded to the bottom and new side tanks. These seem to work nicely and can be worth 0.1 on an 11 second car. They tend to be sneaky, since they look stock from above, but require the front sway bar to be removed if you don't want to make a hole in the scoop to accomodate the sway bar.
Front mounted intercooler
There are several brands/types of these available. All tend to increase flow and provide a denser charge. Some have alot of plumbing that can lead to increased turbo lag. They are fairly expensive (usually $1000 or more) and benefit the more modfied cars. They definitely go away from the stock appearing theme and may contribute to hotter coolant temperatures on the street (depending on mounting and design) due to blockage of the radiator.
The liquid intercooler seems to be a nice modification that is very docile and streetable. It has the advantage of being able to use a very cool mixture of ice and water/alcohol at the track to gain extra efficiency. It is fairly pricey, however.
Chareged Air Systems front mount intercooler
List member Tony DeQuick has come up with a very efficient and well engineered front mount intercooler that seems to be a very popular alternative front mount. Several people have reported a tenth of more gain over their previous front mount.
|What should I do to make my car launch better at the track?|
|Several simple and cheap techniques are used to achieve a car that launches straight and hard, but doesn't affect ride quality on the street. They are listed below:
A very cheap and simple first step. You can get by with installing just one air bag in the right rear spring, but dual bags allow you to adjust things easier. The air bag plants the right rear and helps reduce squat. They are available from all the aftermarket places and J.C. Whitney occaisonally has sales where you can pick up a pair for around $50.
The stock snubber is worthless. The modified snubbers extend the rubber "bumper" to control axle rotation when you accelerate hard. Easy to install and necessary.
The stock bushings work very well, but if they are worn or deteriorated, you may want to consdier urethane or graphite impregnated bushings. They can make the ride a bit harsher, but will make the car handle better.
For the race track, it is often the practice to disconnect or drop the front sway bar. This allows the chassis to lift one wheel harder and to plant the rear better. This can be worth a tenth.
Southside Bars/ATR Traction Shackles
These devices relocate the rear control arm to change the car's instant center. The devices seem to work well on converter equipped cars that really shock the tires on a launch. They actually hurt my car's 60 foot times when the car was in 12.50 trim. The 60 foot times went from 1.65-1.67 to 1.68-1.73s. When I removed them, it immediately picked back up and went 1.63-1.67. I don't use them on my mid 11 car and it has turned 1.52 short times.