Finally picked up my late teens dream car last week - come from the Audi world so the GN is a massive change but loving the car as much as I knew i would.
Your fine , ask away .regrettably I ordered the original style fillers from gbodyparts.com, my bumpers need to be shot as well so my body man will do those when the fillers are being painted. The scan master I'll need for sure, I have diagnostic and logging tools for my OBDII cars but nothing currently for the older. Although I want to keep the car stock what discreet things would you suggest I do to enhance the performance of the car some- I'm not expecting it to run with my other car but a low 13 to high 12 sec capable car would be ideal. Thanks in advance... and sorry for the likely rudimentary questions.
That's very helpful, thanks a lot Patrick. Agreed, modding is addictive so I hope I can resist the temptation for a whileNothing wrong with the stock filler panels, just make sure the body shop adds the flexible agent to the paint. If they skip that step, the paint is setup to fail and will crack. Those ATR stage mods were and are still used today, but, you gotta get rid of that ATR Pitbull chip if you're just running pump gas. Eric at TurboTweak is the go too for a current chip. With regards to stealthy upgrades, if your plans are to keep it as stock as possible, then I would start with doing the Spring Cleaning stuff to get it running 100%.
Next I would do these small mods as a bare minimum.
- Scanmaster (either the v2.1 or the G)
- A quality boost gauge and A-pillar mount.
- A bottle of ZDDPlus oil additive in the oil asap.
- Fuel pump hot wire kit.
- Walbro 340 255lph fuel pump kit.
- Replace the fuel filter (Maintenance item in the Spring Cleaning article)
- Adjustable fuel pressure regulator and a fuel pressure gauge to set it with.
- TurboTweak v5.7 chip, burned for the mods your car has, or will have when you install the chip.
- As a bare minimum, get a drop in replacement K&N filter, if the car has the stock air filter canister setup. If not, you can simply run a 3x9 K&N filter bolted directly to the MAF sensor. It's also a good idea to replace the flexible accordion tube with a MAF pipe. But as a bare minimum, take it off and inspect it for any holes. Especially around the alternators lower mounting stud. A hole typically develops from that exposed stud.
- If the car has the stock catalytic converter on it and you must run one for emissions, I highly recommend having it replaced with a high flow cat, as the stockers tend to fail/break appart and clog the system.
- Valve cover breathers, both driver side and passengers side. If the car has the stock turbo with the valve cover breather tube still attached from turbo inlet bell to valve cover, it is highly advised to install the K&N breather and cap the turbo inlet bell neck with the rubber cap and clamp. This stock valve cover breather tube lets the turbo suck oil in. This oil then puddles in the intercooler and slowly over time, gets blown into the upper half of the engine. This leads to detonation and is not good. If your hoses, throttle body, and upper plenum show signs of oil leakage, the intercooler needs to be removed and cleaned out. Especially if the engine is 100% stock. Even low mileage cars suffer from this design defect.
- I would plan on replacing the valve springs, as if they are 100% original, they are way past their shelf life.
- If the engine is low miles, IE: below 60k miles, chances are the timing chain is in good shape. However, just know that the factory cam gear used a nylon ring of teeth that over time, will crack and or break. With that said, it is highly recommended to replace the timing chain with a double roller and a torrington roller bearing cam button as preventive maintenance. And most say, don't run the timing chain tensioner when it goes back together. Some have with no issues, but, the chain will wear the bumper over time and eventually clog the oil pickup screen. I never ran one on any of my cars after swapping the timing chain.
- I also recommend a turbo oil filtration kit, like Precision's Oil filtration kit, or like the kits that Mark at TR Custom Parts and the one that Cruz Performance sell. The factory turbo oil feed line supplies unfiltered oil to the turbo. As you can imagine, this will eventually lead to excessive wear and tear on the turbos' bearings and thrust bearing. Leading to turbo failure.
- Exhaust preference is subjective, but there is power to be had with a 3" smooth bend Terry Houston style downpipe, a Test pipe and a free'er flowing cat back exhaust system. However, I highly advise staying away from any chambered style mufflers like Flowmasters. You want free flow, straight through mufflers like Dynomax Ultraflow, Magnaflow, Borla, ect, ect. Eventually, even a low mileage exhaust system will start to fall apart.
- If the drivers side header is leaking, typically between cylinder # 3 & 5, it needs to be welded and gusseted up. Have a reputable shop weld it and gusset it up. But be aware that the factory headers, even though they are 409SS, will continue to crack and degrade over time. When the time comes, I recommend either Kirbans stock replacement, TA Performance's complete set, or Gee M's complete set of stock replacement headers.
- Even if you plan on keeping the car as close to stock as possible, I highly recommend RJC Racings' ADD Power Plate for the stock upper plenum. This will help keep from leaning out the back two cylinders, which is a common problem with the factory intake and upper plenum.
- And lastly, if you plan on making more power in the future, upgrade the injectors. As a bare minimum on a low mileage car, I would recommend running some Techron fuel injector cleaner through the system, or having them flushed and cleaned. If the car is a high mileage car, most definitely replace them.
These are the bare minimum things I would do to any 86-87 Turbo Buick that I wanted to have fun with. Always run 91-93 octane with these cars. And always remember to run a bottle of ZDDPlus with every oil change. Most all of the supporting vendors on here sell the parts listed above. Typically, you will be able to run 15-17psi of boost with quality 91-93 octane fuel and all of the above taken care of. Without fear of detonation. Hope some of this helps and congrats on picking up that sweet looking GN. But just be aware, these cars are very addictive and easy to hot rod. And with your Audi experience, I'm sure you already know this. When it comes time for upgrades and making more power, we are here to help. You can post a few underhood shots and we can better tell what's done to it.
I think that ATR document was just promotional, I’m not sure the car has any of those items on it currently - so now I need to figure out where so start - prob the stat and chip?Take a few closeup pictures of your engine. From those mods listed, are they still on? The only thing on the list that I would get rid of is the chip. I'ld stick with a Turbo Tweak chip. While there I'ld go straight to 60lb injectors. They would give you headroom for the future and they work great. The fuel pump is barely enough for a stock car. Upping the pump is good maintenance and gives you future headroom. A hotwire kit is very useful since the stock wiring to the pump is weak. Adding boost just hurts the voltage to it and cause even more issues. Free flowing exhaust with the cat removed is a great mod. Those mods should get you to mid 13s.
I've heard just having a Duttweiler catalog in the glove box cuts 2/10ths off the 1/4 mile time.......I think that ATR document was just promotional, I’m not sure the car has any of those items on it currently - so now I need to figure out where so start - prob the stat and chip?