301 Pontiac Web site and Q & A Subthread.

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jjr:
This article was submitted by a fellow 301T guy and with his permission
I'm posting it here.
 
 Turbo 301 Improvements
 by Bert Rennels

 The following modifications can significantly improve both torque and horsepower for the 301T, while maintaining the vehicles original drivetrain components and therefore its' value. Before making any changes to the vehicle, check with your local laws regarding emissions testing and regulations so you'll know if it's against the law to remove the stuff. You wouldn't want to be in violation of any laws. My state, which uses the Federal emissions testing system, no longer emissions tests cars that were built before 1984. Back when emissions testing for these cars was still required, my vehicle was always very clean burning and easily passed, even without emissions controls on it. That certainly is a credit to the design of the 301 Turbo engine.

  To get more power out of your 301T, you can start by removing heat sources like the EGR (Exhaust Gas Recirculation) Valve and its very hot feed tube. A block off plate can be make from a 1/4" to 3/8" piece of aluminum, by tracing an EGR gasket onto it, then having it neatly cut out at a machine shop. (To avoid warping, don't use anything thinner than 1/4"). The feed tube will not just slip out from under the turbo, unless you happen to have the turbo off the motor, you'll need to cut the feed tube with a cutting disc on a drill, or a short hack saw. Then you can remove the brass elbow from the intake manifold and match up a brass pipe plug to replace it. Torque both the plug and the block off plate (with a new gasket) to 15 lb.ft. Also remember to plug the exposed vacuum line that activated the EGR. In addition to a much cooler intake charge, you will get more efficient fuel burning without the EGR there to dilute your mixture with hot exhaust gas. Don't let anyone ever tell you that EGR helps prevent pinging. It's not true. If an engine pings, it's not because it needs some hot, carbon filled exhaust gas to ruin the air/fuel mixture. If it pings, something else is wrong. Cars were made without EGR Valves for a long time, and many newer vehicles don't use them anymore. There's no such thing as an engine being designed to "need" EGR.

 The heat to the air cleaner (THERMAC), which is the flexible hot air tube that comes up from the exhaust manifold, should also be removed. Along with it, you must remove and plug the vacuum line that activates it, otherwise the butterfly valve in the air cleaner snorkel will not remain open to fresh, cool, outside air.


 The 195 degree stock thermostat must also go. Replace it with a 160 degree thermostat. A 160 degree thermostat will still produce plenty of heat, yes even in the cold winter months. Some mistakenly believe that you need a higher temperature thermostat to get heat in the winter. If you don't think 160 degrees is hot enough, just try sticking your finger into some 160 degree water, and see how fast you pull it out!

  Although it doesn't create nearly as much heat as the EGR valve, the plenum coolant can also be bypassed if desired. You'll need to maintain the proper coolant flow out of BOTH of the 5/8" water outlets from the top of the engine, (the one that's tucked away at the rear of the engine, behind the air cleaner and the one that's next to the thermostat.) There are several ways to re-route the hoses, but whichever way you choose, you'll either need a 5/8" "T" fitting (if you're tapping into the line from the 5/8" rear outlet) or a 3/4" "T" fitting along with a 3/4" to 5/8" adapter (if you tap into the 3/4" heater outlet hose where the stock metal "Y" tube that feeds to the rear of the plenum would be.) These plastic fittings can usually be ordered at most auto suppliers if they don't stock them.

  If  you've got a 1981 model, there's a SLIGHT CHANCE that you may have an EFE (Early Fuel Evaporation) heater underneath the primary bores of the carburetor. I say "SLIGHT CHANCE" because this device shows up in the 1981 Pontiac Service Manual and in the Chilton Manual, in the form of a drawing of the EFE with the 301T's carburetor and plenum. It does not however, show up on the emissions label for the car, nor does it show up on anyones' 1981 Turbo 301 engine, as far as I know to this point. It may be that GM had intended to use it on these engines, then possibly decided against the idea before production. I am including this information just for the SLIGHT POSSIBILITY that the devise may have been installed on a limited number of 1981 production vehicles. This type of EFE is a ceramic heater grid that is built into the carburetors' base gasket. Its' function is similar to the THERMAC, to heat up the intake mixture. You can tell if you have one by looking for a pair of electrical wires going to the front of the carburetor base gasket (one wire should be a ground, the other would probably go to a relay). If the wires are there, disconnecting it will allow the mixture to be cooler, denser, more efficient and more powerful. As with any electric leads that have been disconnected, make sure you tie up and wrap the exposed connector to prevent any possible shorting out. At some point you should also remove the carburetor and replace the EFE gasket with a regular carburetor base gasket. This is because an EFE gasket has a grid underneath the primary bores that partially restricts air flow, kind of like having a carburetor with less CFM than it should have.

  For some reason the 1981 version of this engine was rated at 200 HP, instead of the 210 HP rating for 1980. I've heard some people speculate that the 10 HP loss was due to a "compression drop" from 7.6:1 in the 1980 model, to 7.5:1 in the 1981 model. If you check the Original Factory Service Manuals and the Owners Manuals, you will see that the compression ratio is the SAME FOR BOTH YEARS, at 7.5:1. Also, the part numbers for the pistons are the same for both years, further indicating that no drop ever occurred. The sometimes incorrect Chiltons' Manual listed the 1980 version at 7.6:1, but this information appears to be in error, along with the incorrect HP and torque ratings that the Chilton Manual published for this engine. Interestingly, Chilton used the actual, correct HP of the 1980 model, for the 1981's specifications. Chilton's are useful manuals, but they do make mistakes. The most likely reason for the 10 HP reduction in 1981 is probably just a matter of stricter emissions requirements. This is just a guess...but, it may even be that GM got the lower HP rating after testing a 301T with an EFE heater grid installed on it, then possibly decided that the EFE wasn't necessary on the engine. IF that were the case, an EFE would reduce CFM a bit, and that could easily cause a 10 HP reduction. This is just a theory, it may have never happened.

  If you ever take the carburetor off, you should carefully drill out the plugs that cover the idle mixture screws. If you aren't familiar with these, read up on some Rochester Quadrajet Carburetor literature first, or have someone who's experienced with them do the job. That way you won't damage anything on your delicate carburetor. If the mixture ever requires an adjustment someday, they'll now be easily accessable with the factory plug seals removed. Don't ever swap out your specially designed 800 CFM Rochester Q-Jet for anything other than a genuine factory replacement. It's the perfect carburetor for the 301 Turbo!

  Removing heat sources will result in a denser intake charge, improving power and efficiency. Famous engineer and turbo expert GALE BANKS, says that EVERY 10 DEGREE DROP IN INTAKE TEMPERATURE WILL PRODUCE A 1% INCREASE IN POWER. We all know how hot exhaust is, so imagine how many tens of degrees you're cooling your intake by getting rid of the EGR, THERMAC,etc.

  Some like to open up the hood scoop, at the expense of the highly admired Turbo Hood Monitor. This would be most effective if a custom air box was made to mate up to the hood with a rubber seal to allow ONLY cold air from the open scoop to enter the carburetor. Using an open element air cleaner will allow hot underhood air into the carb. along with the cooler air, and some of the performance gain may be lost. This is why I recommend keeping the stock, ram air ducting in place from the nice, wide air-scoop duct which should be under the front bumper, (if yours is missing, you should find a replacement) to the stock air cleaner, but defeating the THERMAC part of it, (which functions to heat your intake air to 100 degrees at all times, yes even after the engine has warmed up).

  The Air Pump, which is belt driven and therefore robbing power from the engine, can also be removed, and its' metal feed tube in the front of the engine can be capped with a brass pipe cap. If you ever happen to have the power steering pump off, you can remove that metal tube entirely and plug the holes to the cylinder heads with metal freeze plugs. You may want to spot weld them in place to prevent them from popping out. You'll need to get a two groove pulley for the water pump, since removing the Air Pump requires a shorter alternator belt, which will now need to go around the water pump instead of the Air Pump. These 2 groove pulleys are available from some of the aftermarket Firebird and Pontiac parts suppliers. I got mine from a V8 Pontiac Ventura in a junk yard, but that was many moons ago. The vacuum line to the Air Pump should also be plugged. Many don't realize that the design of Air Pumps is such that they actually drain more power from the engine as your RPMs increase, kind of like a parachute in the wind...very little effect when standing still, but more and more resistance as speed increases.

  If it hasn't already been removed, get rid of the Converter. It is literally fighting the effort of your turbo to spool up. Next, straight-thru mufflers are the only way to go since the turbo naturally quiets the noise very well. In fact, you're adding unnecessary restriction with ANY other mufflers, including chamber types or turbo mufflers. 2.25" piping is just fine so long as the mufflers are straight thru. You should have a new, custom bent "Y" pipe made up. It should start out at 2.5" right off the downpipe, (since the Converter is gone), then immediately branch out to dual 2.25" pipes from the 2.5" junction. Make sure you find someone who knows how to make a good flowing "Y" pipe junction. Some actually run no mufflers, just straight pipe. Surprisingly, it's not much different in sound from a normally aspirated (non-turbo) V8 with Flowmaster style mufflers, since the turbine really does quiet things. If you just want a mild performance tone, still with great flow, use straight-thru mufflers that are no longer than 12" to 14" case length. You can get cheap, glass packed ones that'll quickly burn out internally and become just as loud as having no mufflers, or you can opt for the more expensive ones, that retain good sound control. Just make sure they maintain the full 2.25" diameter all the way thru the muffler. If you do use a new, custom made "Y" pipe, you can have it lined up for center in/center out straight thru mufflers for slightly better flow, instead of offset in/center out straight thru mufflers, which would line up with a stock-configured "Y" pipe. Stock tailpipes are fine as long as the inlet is put in a pipe expander to bring it from 2" to a full 2.25", which is the diameter of the rest of the tailpipe. Another bonus to straight thru mufflers is that, upon deceleration, you can sometimes hear a light whirling sound coming out of the tailpipe, it's the turbine wheel spooling down, and it sounds great.


  A good boost gauge, either a testing-type, or permanently installed, will tell you if you're reaching the factory 9 psi boost pressure. Even with all 3 Turbo Hood Lights working, you may be as low as 6 psi., missing out on lots of HP, and never know it. I strongly suspect that inaccurate boost settings, possibly right from the factory, may have been the reason why some people who either owned or test drove one of these Turbo 301's, felt that the car was really lacking in power, while others drove one and raved about the performance. My car, ever since I bought it (back in the 80's), would never light up the 3rd Turbo Hood Monitor Light. I tried replacing the pressure switches, the bulbs, etc. Then I hooked up a boost pressure gauge, and found that I was only hitting 5 psi. boost! That's why the car seemed to have power, but not quite satifying power. You can carefully tailor an aftermarket gauge in where one of your center A/C vents are, (right next to your Voltage gauge). Just be sure to trim your valuable engine-turned aluminum faceplate carefully, by gently filing the opening if it needs to be a little wider. You can use the front of the inner black plastic A/C vent hole to brace the rear mount of the gauge (if you cut it in half and trim it to fit your gauge, leaving the other side of it intact for the remaining A/C vent). If you don't use something firm behind the thin aluminum face plate, it will bend when you tighten in the bracket for the new gauge. If you choose one wisely, the new gauge can look like it belongs there. I used an Autometer Gauge # 2601. The inside of the A/C duct, which will need to be cut to make room for the gauge, can be reshaped with either some new plastic glued into place, or just some duct tape, to keep the duct flowing thru the remaining center outlet.

  Once you've got a gauge accurately hooked up (follow the installation instructions carefully, or you won't get an accurate reading), if you're not hitting 9 psi boost, and if your turbo and its' wastegate actuator aren't in need of repair, you should check to see if your actuator mounting bracket is straight. If it leans a little toward your turbine, you can carefully lean on it to bend it to a nice, straight, vertical position. This solved the problem with mine, and gave the car the performance that I always thought it should have, (all 3 Turbo Lights worked now too). Just don't bend the bracket beyond the point of being straight. That should properly align the actuator, so that it doesn't open the wastegate before 9 psi is reached. If that's not the problem, and you've got one of the threaded actuator rods, you can adjust it. Before you do, get a good book on turbochargers and read up on how to properly, and safely adjust it. At the very least, consult someone with some good knowledge on turbos first. Don't ever play with a turbo if your not 100% sure of what you're doing.

  Once you know you're hitting the proper 9 psi., and you've covered all the other steps listed, you'll probably be quite happy with the power of your vehicle. But if MORE POWER is STILL desired, boost can be adjusted up a bit, to maybe 9.5 or 10 psi., since the cooler intake charge will offset pre-ignition and detonation. Just make sure to use 93 octane gas if you're going to be doing any hard acceleration. If you do decide to increase boost at all, educate yourself about turbos first, get a good book about them, and talk to several experts, that way you'll know what your doing BEFORE you do it. There are inexpensive boost adjusters available if you don't have a threaded actuator rod, or you can get your actuator rod fitted with the adjustable end and proper threading instead. Be careful of some of the many aftermarket suppliers who will SELL YOU ANYTHING that they can. Most of them have NEVER EVEN SEEN A 301 TURBO, and really don't know ANYTHING ABOUT THEM. Most of the time it's just a telephone sales rep. giving you poor and often incorrect advise, to try to get you to buy their products. Once you've studied up, you'll be able to tell who knows what, and who is full of baloney!

  At some point, if your turbo needs a rebuild, you'll want it done by a good, reputable, original equipment GARRETT dealer. Not someone who'll try to sell you their less valuable, aftermarket brand. A good Garrett dealer can retrofit yours with a WATER COOLED CENTER HOUSING which fits right into your original end housings, and prevents premature bearing wear. It would have been nice if Garrett had these available to GM when they built the cars. If you need a rebuild now, or a replacement Center Cartridge, it's the only way to go! Don't let anyone talk you into ceramic ball bearings for your turbo. They don't hold up well. A true expert in the field will tell you that the bronze bearings, along with the proper professional balancing is best. Also, don't let anyone try to tell you that the TB0305 (or T3) Turbocharger on your 301 is not big enough for your 4.9L engine. Many don't realize that there are lots of different size T3 Series Garrett Turbos, and the one on the 301 is MUCH DIFFERENT than the ones used on 4 or 6 cylinder engines. If you look on your turbine housing, you should see the number 82 cast into it. I'm told by a knowledgeable turbo rebuilder that signifies an A/R (area-to-radius) ratio of .82, which is about as large as many T04 Series Garrett Turbos. The 301T also has a 2.75" compressor wheel, and a 2.5" turbine wheel, again about the size of many of the T04 series turbos. Incidentally, I was also informed that the T04 series turbos were originally designed for use in TRACTORS!

  The truth is that the 301T comes with a very well matched turbocharger. It does exactly what the engineers at Pontiac intended...to give you the smooth acceleration and power of a larger displacement engine. If yours doesn't feel that way, it's very possible that the factory 9 psi boost setting is not being reached, and should be tested as previously mentioned. I've heard some people say that they believed that these turbos couldn't actually reach 9 psi due to backpressure from a "too small" turbine housing. As I pointed out before, that is also incorrect. The boost pressure is ONLY limited by an improperly adjusted wastegate actuator. Some think that the exhaust exit port in the turbine housing is too small and accounted for this "backpressure" issue. Well, as you might have guessed by now, it's actually the perfect size for a LARGE 2.5" turbine wheel. The turbine wheel, just like a compressor wheel, has a large end which tapers down to a smaller end to enhance flow, this smaller end is called the turbine wheel "exducer diameter," and this is where the exhaust exits the turbine housing. It's a little under 2", and this "exducer" fits into an exit hole in the turbine housing that is just big enough for it to fit without scraping the sides of the hole. If the exit hole were made bigger, the exhaust would escape around it just like an open wastegate and PREVENT YOUR TURBO FROM SPOOLING UP! It doesn't lower boost capability, it does JUST THE OPPOSITE, IT ALLOWS BOOST TO PROPERLY BUILD UP.

  If you need a new actuator, there are actually some places out there that will split open and rebuild your original one. This eliminates the need to drill out the mounting bracket from your original actuator, to use with a new, universal actuator, (the new, universal brackets aren't angled to fit the 301T).


  If you want to produce an even COOLER INTAKE CHARGE to make EVEN MORE POWER, a good quality, properly installed BOOST PRESSURE ACTIVATED, WATER INJECTION kit, will do an excellent job of further cooling the intake, allowing for a bit more upward boost adjustment. Some feel that the water injection is even better than having an intercooler, since intercoolers produce more lag due to the length of plumbing. I mounted my water reservoir in the right front of the engine compartment, next to the charcoal canister. It tucks in there quite neatly. You can use ordinary windshield washer fluid for your "TURBO ROCKET FLUID," (as Oldsmobile called it when a water injection system was original factory equipment on their turbocharged 1962-63 Jetfire Engine. I won't get into the whole story about the Olds, but it was a similar draw-thru, Garrett AiResearch Turbocharger setup. It had ridiculously high compression pistons for a turbocharged engine, and therefore needed the water injection to allow even a mere 5 psi boost. Even still, it was impressive in its' day). The washer fluid is a mix of water and methanol, which is what's recommended for water injection use. Just make sure your washer fluid is the type without soap in it. You can test it by shaking the bottle, if it suds up, it's got soap in it, so use a different brand. If you do raise the boost after installing the water injection, don't get crazy with it or you'll ruin your engine. I wouldn't recommend any higher than 12 psi., and even with that, be careful, every engine, and every climate, is different. If it's hot outside, the air intake may be too hot for more boost. At first sign of pre-ignition (a popping out of the carb.) or detonation (engine knocking or pinging), get your foot off the gas, and let the engine cool down. Retest it later, and at a LOWER boost setting. Once it gets hot, you are in danger of engine damage, so don't keep going, wait until later. That's why so many have ruined their engines, they got "boost greedy" and wanted more, but got a blown engine instead. These 301's are made to withstand power increases, they don't have a weak bottom end as some have incorrectly suggested, but NO ENGINE can withstand being OVERBOOSTED! That's where the stories of blown head gaskets, melted pistons, holes blasted through exhaust manifolds, etc. come from. It's not that the engine is poorly designed, but rather that the driver pushed the boost too high. Some people think that being able to add more boost has to mean more power, but that's not always true. The extra heat generated by compressing the boosted air further, can actually result in a power reduction, and the engines' ESC (Electronic Spark Control), which works to offset detonation, may need to ~ the timing so much that the extra boost, along with it's extra heat, becomes a waste of effort, and can also destroy an engine. According to GALE BANKS, who has designed some amazing turbocharged engines, every psi. of boost that can be SAFELY increased, will produce a 7% power increase. Some other turbo experts have said that the power increase per each additional pound of boost is actually in the 7 to 10% range, since the 1st additional pound of boost is much cooler than the 3rd. In other words, you may get a 10% increase on 1 additional psi, 8 or 9% on the 2nd, and maybe 7% on the 3rd. This is another reason not to keep trying for higher boost. Even if it doesn't destroy your engine, the efficiency of the extra boost continues to decline because the higher boost makes the intake heat climb.

  The most effective, and safest modifications for your Turbo engine involve cooler intake temperatures and freer flowing exhaust. The goal here isn't to make the 301T the fastest car in the world. The fastest car only exists for a short time, until someone builds the next car with a little more power. However, The Turbo Trans Am and Turbo Formula can be VERY POWERFUL SPORTS-MUSCLECARS, with some of the most HEAD TURNING STYLING OF ANY VEHICLE EVER PRODUCED!

  I don't recommend camshaft changes, cam upgrades are generally unnecessary for turbos, and many turbo experts who really know their stuff have told me that stock type cams are better than larger, high rev. cams in a turbo motor. This is probably why Pontiac did not install the higher output camshaft of the W72 version of the non-turbo 301, into the 301T. After all, if you can bring in your peak torque at a lower rpm, then your boost will spool up faster than it would with a cam that operates in a higher rpm range. Larger cams do sacrifice some low end torque, and usually require higher rpms to reach their peak torque, in order to achieve their higher rpm horsepower. You could actually end up slowing your car down with a bigger camshaft. That's not to say that you can't possibly improve things with a cam upgrade, it's just that you may try it, and not actually get the results that you were looking for.

  As for rear axle gear changes, they reduce gas mileage, so I don't recommend them either, especially with the way gas prices are now. Higher ratio rear axle gears will certainly get a vehicle "off the line" faster, but once your cruising down the highway you'll always be at a higher rpm at any given speed, than you would with the stock 3.08:1 gear ratio. This wastes fuel and actually creates more wear on your engine. The 1980 Turbo Trans Am Indy Pace Car was fitted with LOWER, 2.56:1 rear axle gears to give it the higher speed capability to pace the race, since longer duration speed was the goal, rather than a drag strip race. By the way, the PACE CAR REPLICAS that were sold to the public came with the standard 3.08:1 rear end gears. The original 3.08:1 gears are a good compromise between good mileage and performance, since no overdrive transmissions were available at the time.

  I also don't think any aftermarket ignition systems are needed for the 301T. Though some like to have it for higher boost applications, to get a hotter spark, and there's certainly nothing wrong with that. Without the EGR valve however, you will get a better, hotter spark and more thorough fuel burning. Some of the cars running high boost levels are using ultra high octane racing fuel, instead of 93 octane pump gas, to control detonation. Racing fuel would probably require the ignition system to be upgraded, since the racing fuel is so high in octane that it's harder to actually ignite it. Some believe that the higher output aftermarket ignitions are needed to prevent the stock ignitions' spark from being "blown out" from the high boost. Well, there are a couple of things they might not realize...1st, we're not talking about blowing out a candle, it's an arc of electrical current, not a flame... Have you ever seen a hurricane wind "blow out" a bolt of lightning? No? Me either. 2nd, even if you could "blow out" the spark with boost pressure, you'd need the intake valve to remain open when the spark plug fires, instead of properly closing. If the valve did remain open, the explosion would travel up your intake manifold and come blasting out of your carburetor. It's possible that increased compression generated by high boost could require more voltage to burn the larger amount of fuel/air mixure, but the more likely cause for needing an aftermarket ignition is the use of racing fuel. Not only is a good quality, boost activated water injection system a much cheaper alternative to filling up with expensive racing fuel, it also does something that the racing fuel can't, IT COOLS THE INTAKE CHARGE, instead of just using more octane to prevent detonation.

  All of the above modifications will IMPROVE MILEAGE, EXTEND ENGINE LIFE (so long as you don't abuse your classic/antique Turbo Trans Am or Turbo Formula by racing it), and increase BOTH TORQUE and HORSEPOWER. I know some people do like to go to the track with these machines, and I commend their very successful results, but I'd rather keep my engine from needing a rebuild, or worse, a replacement! The last time I checked, Pontiac wasn't making them anymore! Once you damage your engine to a point where it's not rebuildable, even if you can get a replacement motor, the cars' value will never be the same as it would with the original engine and transmission intact. If you check the NADA Book Values you'll see that the value of these cars has been skyrocketting. If I were going to the track, I'd rather put my precious 301T in a safe corner of the garage, then drop in a small block Chevy engine since they run great, are easy to hot rod, and MOST IMPORTANTLY, easy to replace. Better yet, maybe I'd use the Chevys' body too, I don't want to nick my beautiful "Screaming Chicken" Hood Bird! Lastly, if you do want to race it, do it at the track, and ONLY AT THE TRACK! Nobody wants to get hit by some fool, driving like an idiot on public roadways. Remember, we're 301T guys, we KNOW BETTER than the average gearhead.

 Written by Bert Rennels

bodisnatcher:
Is there a difference between the 80 and 81 turbo air cleaners?  The reason I ask is that I can still get an air filter for my 80 but the local auto parts stores don't carry one for an 81.  The books they have cover Fram, STP, and Purolator.  The Purolator book still has a number but there was a footnote that stated *until inventory was depleted.  Of course, it was already depleted.  Thanks,

Dewayne

jjr:
Yes, 1980 and 1981 air cleaners are different.

 The biggest thing is the second charcoal ring that traps
fuel vapors.

 I've never looked at the paper elements to see how close
they are though.

 Try Oreillys or anyone that carries WIX filters, Have them
look it up and order it for ya.

 I know I got a correct '81 one just this past spring...

 Then let us know where you got it in case someone else asks.

 Joe R

jjr:
They speak Turbo!

 One aspect of posting here and having a 301 website is the mail you
get. In addition to the many thanks and parts sourcing requests are
the pleas for help.

 Often today's young auto techs were in diapers when these cars ruled
the roads and so finding competent service can be complicated. Don't
get me wrong, there are some very sharp young folks who can get the
correct info and do it right... It's just not the majority of techs
unfortunately. In fact, if it's got a carb - you might be out of luck
anyway.

 Recently I had the pleasure of working with a man and his shop in
helping them complete the repairs on a '81 Turbo Trans Am.

 I'd like to introduce Mr. Bo Woody of Automotive Performance Specialists
in Oklahoma City, OK. (405)424-7223

 Apon completion of his work, I asked him for an account of his work. The
following was his responce.

 And no, he did NOT pay me to do this, it was my idea to show TA fans
that there are in fact shops that: "Speak Turbo"! Any shop that does
the right work, espically on Turbo cars deserves due credit.

>

 Dear Mr. Richter,

  Mr. Olsen contacted me by phone in referrence to his 1981 Turbo Trans Am. He was concerned that some work performed at another local garage may have been incorrect. I made Mr. Olsen an appointment and on 10-22-07 he brought the vehicle in for inspection and repairs. His concerns were a coolant leak and a power steering leak. He also voiced a concern on whether or not the other repair shop had correctly adjusted the ignition timing, and the fast idle speed was extremely high.

  Upon initial inspection we discovered the upper radiator hose was leaking at the thermostat housing. The repair was to remove the upper radiator hose and look at the connection. We found some corrosion on the thermostat housing that we cleaned up with some Scotch-Brite tm. We then removed the corrosion stuck to the inside of the upper radiator hose and reassembled everything and retested for leaks.

  On to the power steering leak. Initially the power steering leak appeared to be the pressure hose and on further inspection we also discovered the power steering reservoir leaking from being distorted by someone prying on the side of it to tighten the belt. We replaced the P/S pump and reservoir, and the power steering pressure hose. We then retested the system for leaks and concluded our power steering repair.

  Now to the timing. Upon initial inspection I realized the bypass connector being grounded made no difference whatsoever in the timing or the timing curve. So I refer to a manual I have and it seems to try to lump the 301 NA, 301 Turbo, and 265 engines into one diagnostic procedure. Anytime you find this and you are dealing with lowest production vehicle of the three, chances are your diagnostic procedure will only vaguely touch on your specific problem or not at all. Sure enough this was the case. At this point I have to fall back on experience and a solid working knowledge of the ESC system. First things first the vehicle was 27 years old and time takes it's toll on wiring harnesses and connector integrity. I decided at this time to take a look inside the distributor cap and see how it all looked. I found the 3-pin plastic connector on the 5-pin side of the ignition module broken and the wire closest to the stator completely unplugged from the module, and grounding to the inside of the distributor housing. I breathed a sigh of relief feeling sure I had found the problem and would be finished soon. I replaced the connector with one out of another large base ESC distributor, and reassembled everything just knowing that would solve the ESC bypass problem. It did not and it didn't make any difference in the symptom either. ONWARD! I began troubleshooting the harness to verify all circuits had good continuity between the ESC controller, ESC ignition module, and the ECM.

This is where it started to get tricky. Even though I had an original GM wiring diagram it was almost impossible to follow for the turbo cars, and the turbo cars are completely different in relationship of where each wire is connected. Some models will run one of the four wires from the distributor mounted ignition control module directly to the ESC module where the same wire goes directly to the ECM on a turbo car. At this point I had to clean the wires at the distributor connector, verify the correct color code on each wire was in the correct connector socket. All that checked OK. Next I ohmed out every wire from the distributor four wire connector to the ESC and ECM, and all the wires from the ESC to the ECM. During ohming the harness I found 2 wires that were over 5ohms resistance. I found the bad connections in the crimps at the ESC module connector. Upon repairing these crimps I retested the ESC system and now the bypass circuit worked normally. I set the ignition timing, tested the knock sensor with the hammer test, and all was functioning normally.
 
 I found while working on these other systems a few vacuum hoses that looked sorta out of whack. I decided next to spend a couple of minutes just in general overview when I realized the vacuum hose to the EGR control solenoid was just dangling down in the intake manifold lying on the valley cover. I thought Hmm and looked at the core support vacuum diagram and sure enough it goes right where it goes on the carburetor on every other early to mid eighties Q-jet (baseplate right hand corner). Well the carb port for the EGR had a hose on it running to the AIR management valve. The carb port "B" for the AIR management valve had a brand-new appearing vacuum cap on it plugging it off, so I removed it and connected the proper AIR management hose. FIXED RIGHT?-----------WRONG! I start checking the routing of every other vacuum hose. The Thermal vacuum switch in the side of the air cleaner single port side was conneted to the canister purge valve instead of the thermac sensor on the bottom of the air cleaner. The Baro sensor was connected to the rear intake manifold tree (manifold vacuum instead of being vented). The MAP sensor was connected to carb port "D", and the proper point of connection in the wastegate hose had a fresh new looking vacuum cap on it as well.
Charcoal canister purge control port was connected to the cruise control dump valve instead of the canister control solenoid. By the way all these vacuum repairs corrected the cold fast idle speed as well.

  Needless to say now the car runs just fine, and 90 percent of the time spent on these repairs was caused by someones incompetence, inability, or lack of pride in their quality of workmanship.

Sincerely,
Luther B(Bo) Woody

>

 So, if you live in or near Oklahoma City, OK... AND need your Turbo TA worked on, go talk to Bo and his folks... They speak "Turbo!"

 Joe R

jjr:
11/10/07

 Folks,

 Jim Puehl

 jpuehl@charter.net

 wrote me with a clearance list of 301, 301T and Pontiac parts to sell.

 I am posting this for him, please contact him if you are interested...

>>>

So here is a list of stuff I have that I would like to find a new home for.
Some of it is 301 specific and some is Pontiac specific and some of it is
general parts I used on a Pontiac. I'd really like to find a new home for
this soon as I'm cleaning out my garage and I've had this stuff for a while,
but just haven't had the heart to throw it out.

301 turbo parts:
Hood - in very good condition, complete with scoop insert, wiring harness
and turbo heat shield.
Intake manifolds - 2 ea
Engine gaskets, including 5 301 intake mani, 2 regular Pontiac intake mani
Auto flywheel
Carb Plenum - 2 ea
Carb plenum bracket - 2 ea
Exhaust mani outlet flanges
turbo turbine outlet pipe flange
1 pair valve covers
factory exhaust cross-over - 2 ea with flanges
factory exhaust mani to turbo pipe with flange
throttle cable bracket (?)

301 parts:
New 301 4bbl N/A replacement cam (or so I've been told) Wolverine CS-682
Crane Cams Rockers, stock replacements 28800-16
L & R mount mount bracket (bolts to block)
3 timing chain covers; 2 for 301 (doesn't have timing pointer/indicator
rebuilt starter

Generic parts:
Accell HEI coil
'68 AC/Delco shocks - all 4
Deep turbo 350 tranny crome pan
B&M racheting shifter
Holley Red fuel pump - used once to test a fuel system problem
Moroso fornt drag springs (2nd gen firebird), cut to get correct ride height
K&N X-Stream air cleaner top - 14"

Let me know if someone you know are interested in any of these parts.
I don't want to throw them away, but if there's no interest in any of them,
there's no point in keeping them

Jim

>>>

 Joe R

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