2seater

I'll be there, but not until Thursday. Haven't tried Norwalk yet, and that would actually be closer.

Are we talking 3.8's or the later 3800? There 3.8's which were used as fwd in '86 look like a hybrid of Grand National and 3800 parts. The intake is clearly different than the Series I which came out in '88. Two intakes on each side are side by side, like a small block Chevy, where the 3800 are all evenly spaced, so the intake stuff will not interchange. The exhaust is a little murky. I have a set of old cast iron manifolds from a Riviera, and I believe the bolt pattern may be the same, I would have to check to be sure. The exhaust port design of the 3.8 is not as good as the 3800. I have seen data on head flow and the stock Series I 3800 head flows almost as well as the Stage 1 heads for the GN's and better than stock 3.8's which have been ported. I do believe all the Series I intakes and exhaust will interchange, through whatever year the were made, '95? The electronics to run some of the items, like the EGR are different though. I agree with Padgetts assessment that the rear manifold was done as a compromise for space consideration, although if the engine is indeed installed from the bottom, installation at the factory would not be a problem . Removing it afterwards may not be possible. It really needs to be longer at the outlet to make a nice smooth transition and join the front and rear pipes near the outlet. This could be done and I have seen some fine looking aftermarket headers for the Series II. I do not know if they would fit as the heads are closer together due to a lower deck height on the block. The crossover pipe may be the only thing that needs to be modified? For a naturally aspirated engine, I am not sure it would be worth the cost unless other changes are made, such as a cam to extend the rpm range where high flow headers would be more worthwhile.

I checked the coil and the secondary is between 11.66 and 11.76 k ohms. The primary is 6-7 ohms. The manual only lists the secondary and I am almost dead center of the 10-13 k ohms listed. The ICM looks perfect on the inside. I may take the coil along to the GS Nationals next week to see if the guy with the coil load tester will have it there (Caspers Electronics). I should be able to pickup a stock coil for $50 or so or maybe they will have the later model Delco ICM and coil packs for a reasonable price. Maybe my "chuggle" is just a symptom of the reduced .048" plug gap I am running in defference to the boosted condition? Sensor readings all look good, timing is stable, fuel integrator bounces around 128, O2 crosscounts are in the high teens to low 20's, injector pulse width is pretty stable too. Plugs, wires and 24# injectors are all relatively new, maybe 2-3k miles on them. I just had the intake off to fix an oil leak and the injectors are dead clean on the business end. It feels like ignition. Thanks for the help.

Thanks Padgett, I will look at the coil pack resistance. I have heard many stories of coil packs that test okay but it requires some sort of dynamic testing equipment to actually simulate them under load. Did your VOM testing turn up the bad ones?

I agree, it would be better to change to the more modern system if repairs are in order. It's sorta like the R12 vs 134 debate. Changing for the sake of changing probably won't pay for itself, but if it needs to be repaired, the equation changes. Reading GM Ross's description of the "chuggle" at some speeds does sound similar to a phenomenon I encounter also. The engine acts like it is on again, off again at low rpm in high gear, like 50 mph in fourth and locked up. I cannot find any sensor readings that are out of whack while this happens, but more spark or a wider gap may help this. Don't know yet.

I have watched the discussion of plugs and coils with some interest. There is no doubt technology does get better over time, but there are false steps along the way. Just look at the change in the Rapid Fire plugs. I have used platinum and plain old standard style plugs with what seems to be equal success. I have observed the spark from both types of plugs and have always felt the platinums look thinner and "colder" than a conventional style plug. Either one seems to work fine in the engine. The amount of voltage potential of the coil is only relevant if the fuel/air mix cannot be fired with the standard system. If it only requires 15-20k volts to fire the plug, that's all the coil is required to produce, and a higher potential only gives more headroom if the system deteriorates. The much maligned Magnavox does a pretty good job in stock form. If you have ever observed the distance that spark can jump, you will know it has a lot more potential than the old single coil systems. Even though each coil fires every revolution, it still has triple the dwell/recharge time of a six cylinder with a conventional single coil ignition, and four times a V8. I do watch every year at the GS Nationals what the GN guys are running and I rarely see add on ignitions or other than the stock Magnovox until the cars get into the 10's or faster. I haven't observed any misfire issues with my system, which is the stock Magnovox and plain old $0.89 Autolite plugs gapped @ .048". I do index my plugs when installed to expose the open side of the electrode to the combustion chamber, but that's about it. I can't say more isn't better, but so far I have not found a need for it.

I agree the total power potential of the turbo is greater, and the increased backpressure seems to be overcome pretty easily. There are definitely plumbing issues to deal with and heat radiation has to be considered carefully. The one thing I do like about mine is that it is sorta self-propagating. Boost equals more exhaust flow which in turn spins the turbine and compressor faster, which gives more boost etc.. I also agree with Padgett that the maximum the stock system can handle can be achieved with either system. I also believe the supercharger has better air distribution inside the intake, whereas the increased air flow from the turbo inside the stock intake accentuates an unbalanced situation. I watch with interest one of the IHRA drag classes that allows nitrous, s/c or turbo's. One year one system will be faster, the next another will dominate. It seems boost in any form can give you the thrill you are looking for, but they can always be improved through careful testing and modifying.

Greg,(plus others), and I have discussed the pros and cons of turbochargers or superchargers, and each has it's strengths and weaknesses. The S/C would seem to have the advantage of quicker response time, particularly at low speed, and that is somewhat true. I found my turbo setup spooled up more quickly than I wanted, so I turned the boost down to slow the power delivery. I always looked at this as a bit of an advantage with a relatively low traction fwd and a transaxle which is probably marginal if hot rodded too hard. The turbo is still responsive enough to hit full boost during the time it takes to downshift at highway speed. The s/c also has the advantage of being somewhat simpler to install, since GM has already done the work for you, you just have to buy the parts. It should be possible to retrofit the Series I supercharger to the stock 3800 in the car now, but there would be additional parts to be relocated besides the 'charger itself. The advantage of changing the whole engine, would be the possible greater strength of the engine it was designed for, although I do not know of any evidence this is true, on the Series I that is. The Series II is a different animal and does have several improvements. The turbocharger requires a lot of hand fabricated piping to make it work, and both the S/C and turbo have issues with ECM control of the timing and fuel flow, since both will produce more air flow than the stock MAF and ECM are programmed to read, plus the ECM has no boost sensing ability. A lot of what you want to do has to be done through "cut and try", since there is only a small pool of people that have done either one. I seem to be the only turbocharged Reatta, which does work well, but there are still issues to deal with, particularly engine knock and spark retard. As for driving fast, the car actually does seem to like running at speed around the engine torque peak rpm, or in the 70-75 mph range in the '90's and earlier engines. It will run a lot faster, it just isn't a rocket getting there.

You do not have to remove the starter, but you will need to remove the plastic cover from the bottom of the flex plate area. The oil filter adapter is partially in the way to pull the pan straight down, if your filter adapter hangs straight down, but it will come off, although you will need to remove the filter. The one piece Fel-Pro gasket came with four long plastic "studs" which are split in the middle which are installed on the four corners of the block. Th gasket can be installed over the studs so it hangs from them and then the oil pan will hang from them also. This will allow make sure the gasket is lined up and then lift the pan straight up.

I don't know about your '90 but mine is turning less than 1500 rpm @ 50. Tire size wouldn't matter as the VSS signal and engine rpm are linked before the actual rubber meets the road. As for the 3.33 gear ratio vs the 2.97 in the earlier cars: the '91 used a slightly larger diameter tire as standard so to compare the two, the '91 actually performs like a 3.25 ratio would in an earlier car, with smaller tires. Small potatoes, but it is not quite a direct relationship.

They probably actually spin more when getting worn or dry. I have had sucess taking the seals out of the sides of the bearings and repacking it with a small amount of bearing grease. If it is not sloppy you can remove and reinstall the seals after adding a small amount, not packed full. I know I am a cheapskate, but I have done this on more that one make of vehicle.

Although I am not a fan of nitrous, it is probably the quickest way to add a little horsepower. Greg Ross's S/C engine and my turbo install do work, but neither is simple and I still have a knock issue to get under complete control. The other downside to nitrous is the bottle will need to be filled at regular intervals. You can do the cold air intake and open up the rear exhaust manifold to gain maybe 2-3%, which will be noticeable. Optimize the existing system as much as possible, plugs, wires etc.... If it has 100k miles on it, a new timing chain may help sharpen it up too. Plus, run plain old 87 octane for the snappiest performance with the stock chip.

You're not a nut, just obsessed Too much track time has gotten into your blood, but I agree with you nonetheless. Conventional tire to rim matching has allowed up to a 235 tire on a 6" rim. I imagine this is to promote a softer ride due to sidewall flex and running with a somewhat lower pressure to get a flat contact patch. I suspect this is what got Ford/Firestone in trouble. The closer the rim width is to the tread width, the better the handling.

A common place for a rattle at idle is also the vibration damper at the front of the engine. The rubber deteriorates and it rattles. The modulator is at the top front of the transaxle, and the vacuum end faces straight at the front of the engine. If you trace the two small steel vacuum tubes from the vacuum block on top of the manifold, they run down by the upper front "dogbone" mount and turn to the the drivers side. One goes to the modulator and the other goes to the charcoal canister for the fuel tank. The transaxle does have a pretty firm downshift when coasting down at around 14 mph. It should be smooth otherwise.

Usually the fuel pressure goes high when the regulator fails, but, it would certainly be worth a try restricting the return line for a test. If there is indeed trash in the fuel system, it may be possible that it could block the regulator open and pressure would be low. 20 psi will hardly run the car, if at all.

Oddly enough, I saw a post recently on the LeSabre.net that mentioned his fuel lines had clogged with crud. If this the case in your situation with the stalling, it would be worth looking into. The system is under 40 psi or more of pressure, and any sort of perforation of the lines should show up as a definite leak or at least a strong fuel smell. You really don't need the large 1/2" hoses to supply enough fuel to your engine, the stock size is plenty adequate, as long as they are clean inside. The simplest way to check for the problem would be to disconnect the lines at each end and try a compressed air blower through the line in the normal direction of flow. Be carefull as it will spray residual fuel from the tube. There should be three lines, pressure, return and one to the charcoal canister.

Higher octane is a waste of money, unless you have knock problems. The engine will be more responsive with plain old 87 octane, and it "may" start better too. I experienced hard starting several years ago and the first thing the Buick garage suggested was changing back to standard octane. At that time, it did seem to help. Since that time I had a premium fuel chip and added a turbocharger now, so 93 octane is required. The hard starting problem never came back, and it always ran well once started. Regarding the performance question as it relates to octane. Try this simple test, with whatever fuel you are using, try a couple of full throttle starts from a dead stop.When you refuel, try the other grade, and try the test again, preferably in the same place and at about the same atmospheric conditions. I would bet you will find more engine response, (and wheelspin), with the lower octane. If you didn't get a big stream of fuel when you prime the system by turning the key on, that is no doubt the problem. 40+ psi of pressure has the power to send a stream many feet in the air and you have to be very carefull if the engine is hot or running.

I agree with Padgett that the engine only has so-so breathing ability unless internally modified, however, reduction of restrictions on the intake and exhaust will help to a certain extent. I have looked at the exhaust and have thought about what could be done. JC Whitney has nice mandrel bent elbows in mild steel or stainless, and I have used them before. The project would be pretty straighforward, especially if you can weld stainless steel, otherwise you end up with a bunch of clamps. If I remember correctly, the 2.5" '91 Reatta exhaust is still available. The elbows are not mandrel bent, but are probably acceptable for our use. The 2.5" exhaust size will allow a 250hp. engine to breath adequately. If you go larger than this, there will probably be a reduction in low speed torque as the exhaust velocity drops too far for effective scavenging. I am still using the stock 2.25" exhaust with my turbo, but I would like to go larger. The 2.5" exhaust should have 23% greater flow capacity. I have seen modified headers like Padgett describes on late model 3800's and it would certainly be possible to make a different rear manifold that will separate the front and the rear completely and join them a little further down than at present. The front manifold isn't terribly bad, at least the little head pipes are pretty much aimed in the right direction, the rear could stand a lot of improvement, more than just opening up the outlet. Regarding that rear restriction, I discovered a 2" hole saw is an almost perfect fit to remove the restriction and the portion of the O2 sensor weld boss that hangs in the stream. It definitely speeds up the process, and only requires minor finishing. A sharp hole saw, slow speed and a lot of coolant is required.

The cam sensor is still needed for the proper sequential fuel injection. The crank sensor must be different when they went to the 3800 style engine. It generates two different signals, one has 18 evenly spaced and the other has 3 unevenly spaced and sized slots, which generates the proper signal for the ignition module to determine which coil to fire. It cannot determine which cylinder is on compression, so something more is needed to correctly sequence the injectors. Without the cam sensor, it still has sequential injection, but the sequence could be wrong, it doesn't switch to batch fire.

Maybe on an '86, but it should not do so on an '88 and later. The cam sensor isn't needed to determine the correct firing for #1 at TDC as it fires the plug on exhaust also. The Riv and Reatta share the same manual, and the general operating system. I suppose anything is possible, but it shouldn't have any effect on starting on this engine. I will be very interested to see what turns out to be the problem.

The cam sensor will not affect the way the car starts. The timing of the injectors pulse may be incorrect, but you can disconnect the cam sensor and the car will start and run. The cam sensor cannot slip on this engine, it his held by a single bolt and is o-ringed into the front cover. The sensor can be bad, or the magnet in the cam sprocket can fall out, but it does not have any effect on spark or timing of the spark. While the crank and cam sensor do use common power and ground wiring, they do not interact.

It sounds like whatever the problem is has reached the point where you will be able to find it. The '88's had a bit of a problem with the cold start priming shot was not enough to start the car. If you turn the key on, can you hear the fuel pump runs for 2-3 seconds? If not, either the pump is bad, or the fuel pump relay has died. If the pump does run, try turning the key off, wait 20 seconds or so and turn it on again to give it a second priming shot then try starting the car. No start is either no fuel or no spark. No spark could be the crank sensor, ignition module, possibly coil pack or the ECM itself. The odds of all the injectors dying at the same time are slim, but they are all run by the ECM.

That is a much larger bar than mine. It should be a good deal, and I wish I could change to that bar, but the end links are completely different.

You didn't mention the year, but the 1.25" size sounds a little large. I do seem to remember the 88's had a larger bar than my '90, so maybe that is correct. The only other thing I can say is it is straightforward to change them, but you will need the correct bushing shape to fit in the stock location. The bushing sits against a "step" in the crossmember and the clamp has unequal length arms, and the bushing itself is not symetrical either. A conventional style bushing and clamp could probably be used if you fabricate a spacer to fill in the step in the crossmember to give a flat surface. The bushing may be a different style than I described if it is other than a '90.

I have never known of a K&N filter to cause any problem with the MAF, I've had one for years, and the GN guys use them all the time, although the MAF is a different style, also goes for many other makes that use a MAF sensor? The first thing to check is the fuel pressure. The "electrical problem detected" could be many things, even poor charging or battery connections. Can you read trouble codes through your touch screen? A failing coil pack or ignition module will usually not set a code but will give symptoms like described. The last item which is showing up more and more, apparently due to age more than mileage, is the ECM itself, which doesn't self diagnose either. Essentially, there are many things that can cause a loss of power, if the air stream is open and clean, the next thing is fuel, then spark and finally controls for the above. The engine will run with almost all sensors disconnected, as the computer will revert to stored values, so the suggestion of disconnecting various sensors to see if it changes the way it runs is a valid one. Also, disconnect the battery and check the connections, particularly the + for corrosion. This is a common problem that is well hidden by the side terminal connectors. Also check the main stud on the alternator is clean and tight. Disconnecting the battery will also reset the ECM to default values so the engine should run differently, maybe better, and the sensors will come on line when the temperature is high enough to go into closed loop operation, and it relearns operating parameters. The O2 sensor usually shows up as poor mileage, and usually doesn't have the magnitude of effect on driveability you describe.