2seater

Well stated. While the GN community had (and still has) a large performance following, the Reatta was never intended as such, so never generated the hackers to decode the system. The late models cars, particularly the supercharged ones again have a reasonable following, and a fair sized aftermarket. We are pinned right in between the two, and the operating system is out of date. Even for the GN's, there were only a few people that did the majority of the decoding, so one person can make a difference. I would be happy to contribute to some of this work that is beyond my knowledge. Padgett can certainly speak for himself, but I imagine the reality of his real life leaves little time for this project.

I'm with you on that one. Now finding someone with the time and expertise will be the hard part

The BLM is reading pretty low for cruise mode. It looks like it is pulling fuel for some reason. Did you read the integrator at the same time to see if it is bouncing around 128? If the system is somewhat out of balance, it may make it more knock sensitive. The knock retard seems a little high, but it isn't terribly unusual to see a little when the throttle is changed rapidly. It is possible to catch the ECM at a high timing number like used for cruising and then load the engine to where timing should be lower and it may knock momentarily before it can adjust. This will be especially true if the octane isn't what it should be. I know I had a fair amount of knock retard when I took the car to Kansas this past summer and the best gas I could find was 91 octane with ethanol in it as well. The car would hardly tolerate even moderate throttle input witout showing some retard. Of course mine is boosted, but the result is the same on any engine that wants more octane.

An expanded table would be a help, but I do not know enough about the programming to say if it would be a cure. Padgett's point is exactly right, it isn't as simple as it first appears. There are a lot of interelated tables, one modifies another when a lookup point is reached. For example, there is a table for timing modification based on air temperature vs engine load (LV8) When inlet air temperature is high it will roll back timing and actually add timing when cold. The table can be tweaked, and the GN guys used the IAT sensor input with a modified MAP sensor to tell the ECM a substitute for true boost sensing. Sort of a work around to get variable timing based on boost. This sounds sort of encouraging and given the time and expertise, maybe something could be worked out, BUT, if the engine load is maxed out at even a little boost, the table becomes almost irrelevant, since there is only a small portion that can be of use. Essentially, there are a bunch of tables to modify things, but they were designed to work in the expected range. When boost is added, it goes to the top of the table, so there is only one cell that is active. Engine load or LV8 is a key element in the programming, it determines a lot of what portion of a table to read, and in my case, the LV8 goes to maximum, a reading of 255, within a second or two of heavy throttle input. It isn't hopeless, but some bandaids will probably be needed, rather than pure programming, but that is a weak area for me

The GN's did not have boost sensing per se, but, they did have programming designed for boost from the start. Their MAF range went to 255 gm/sec, which by my calculation can measure air flow for over 300 hp. The programming can be used to modify fuel and timing over that entire range, which would be all of what a stock GN could produce. The programming also would start to pull boost at some programmed point, partially based on what gear they were in, of particular interest in a turbo application, where greater engine load actually produces more boost. When the GN pilots modified their engines for more boost, they too would push beyond the limits of the programming and they had to resort to the same sort of dead reckoning we are forced to do, ours will just occur sooner. Initially they used things like a seventh injector to add fuel at some point, alcohol injection systems, bigger injectors, MAF translators, or pushing the fuel pressure higher and of course reprogrammed chips. In this respect the supercharger offers some advantage in that the s/c is coupled directly to the engine where it will be more linear in the air flow capability relative to engine speed. If you load an engine hard at low rpm with a turbocharger, like against the brakes, the turbo will spool up independant of the engine speed. Essentially a turbo is sorta load based and a supercharger is rpm based. Internally, the GN's were somewhat different and similar at the same time. They used rolled fillet crank, similar to ours, but the rods are shorter and the pistons were a cast design with a steel insert. Very heavy by comparison to ours, which look like race pistons in comparison. The oiling system wasn't as good, and the heads are less efficient than ours too. The placement of the intake valves was also different, making the intake manifold have two side by side ports on each side, sorta like a Chebbie small block. If you look at our firing order, this isn't terrible since the two close together ports are not in sequence on each side, but I believe ours is somewhat better with even spacing. I know I digressed but the problems are the same, we just don't have the same broad ECM hacking and experimenting that has been done for the GN's. Even though our ECM has a bigger chip and more capacity, it wasn't designed from the start with boost in mind, so we need to take a best guess and modify from there. The whole system is probably more fragile, but can produce very noticeable gains, and should be used with discretion to make it live. A steady diet of drag racing and high boost would not be a good idea. Even if the engine behavior can be brought under control, the next weak link will be the transaxle. High speeds are not a problem and power for passing and such is relatively safe, where the trans can handle it better. It doesn't take much space for passing slower traffic, and I am sure Greg can attest to that. Oop's, almost forgot Don B.

The supercharger has a captive oil system, no external lube required. It is also a separate part that sits on top of a lower intake manifold, in other words, it is two pieces to get it to fit the engine. The first s/c engines were rated @ 205 hp, then 225 and 240 when Series II came along, as well as a larger s/c which required the injectors to be moved to the heads. The Series II engine is also slightly smaller externally. It has a lower deck height for the block which moves the heads somewhat closer together, so it is probable the upper parts of a Series II won't fit a Series I. I believe there are other differences as well. The Series I stuff "should" fit our engines. I know there has been much discussion of the engine internals and as far as I can find from other sites, the internals are the exact same, the only possible difference being some did use full floating piston pins. The materials are the same, but the part number on the rod and possibly the piston may be different due to the floating pins. The crank is definitely the same. No exotic parts were used, at least none that I can find. When I rebuit mine, I did use hypereutectic pistons, an upgrade over stock cast, but not as strong as forged. Many years ago a guy tested an LN3 engine to destruction to see what sort of power it could hold. He was looking for viable replacement blocks for the older GN style. According to his dyno data it blew the crank out the bottom @ 500 hp. It would seem some headroom is available for moderate upgrades and using the power with discretion. An oil cooler for the engine is a good idea in any case, I run a B&M stacked plate type as welll as one for the trans.

It may be fun to watch, or even do, but not a good idea.

Maybe? Old, rock hard tires would be easy on the transaxle, they will simply go up in smoke No offense meant on the original thread.

Is $500 for the whole package or just the injectors? New injectors in a decent upgrade size will cost about half of that. The whole project will take a while, swapping injectors should take less than an hour.

Good idea to keep them for judging purposes if that is your goal. If not, the stock tires are way behind the newer technology available. Even carefully stored tires gradually deteriorate just from atmospheric effects. The good thing is most of us don't stress them close to their design limits so they last longer in careful use than they should. Tire manufacturers are of course trying to sell tires, and minimize their liability, but 15 year old tires are well beyond their recommended lifespan.

The stock transaxle will last for a while if you do little drag racing. So far I have 25k miles on mine turbiocharged, 121k total, and still works well. The stock injectors can take you to maybe 200 hp or so, no matter what you do with the programming. For anything more, you will need more fuel through larger injectors, although they should come with the top end of the donor engine. GMTuners can help with getting the larger injectors to run well using the stock ECM.

I've done it two ways. One is with a die grinder and a long carbide burr. The other is with a good hole saw that just fits inside the opening (and lots of coolant). It doesn't hurt to take out the part of the O2 bung that hangs inside the hole as long as a couple of threads are left for the sensor to screw into. In both cases the manifold was off of the car.

RPM stay around 1500 in neutral coasting at 50 mph or so. Read the counts for the IAC and it will be elevated. I am not certain why it does this, possibly to keep the engine close to the rpm it would be in for the speed and gear for smooth transition when shifted back into gear? I don't believe it turns the injectors on an off like it does coasting down in gear.

Why? If at idle speed it shoudn't do any harm and I do just that if sitting a long time, like waiting for a train etc.. Beyond that, I don't see a purpose. The ignition timing drops back a few degrees if idling in park/neutral, and there will be a slight increase in trans. fluid temperature after a prolonged idle in gear. I doubt there is any significant difference in fuel mileage, plus I prefer to be able to move instantly in case the situation demands it in traffic. Just random thoughts.

I have a gauge under the hood connected at all times. This may not be for everyone, but I pulled the valve core from the test port. A #4 JIC 90* swivel screws right on the fitting. There is very little room for a hose that stands straight up with the hood closed and it will rub on the insulation, hence the 90 degree fitting. I used short length of fuel injection hose and hose barbs connected to the fuel rail fitting and to a 100 psi gauge from the hardware store. The gauge is zip tied to the front fender brace.

Likely the wrong pigtail, but it doesn't matter now. For whatever reason, GM used two different pin locations for similar MAF hookups, and I suspect you ran into bad information in the parts guys computer. I am very glad it is now fixed. After a bit of driving, everything else should settle down and the other readings will be happy too

I cannot read the number on the one that is on the engine in the car, but my original engine TPS is the same model, SERA 363-1 with a painted #9425 also Japanese (as is our MAF). Just so we are on the same page, as connected, my TPS has the black connected to the plug at the rear (firewall side), the blue is in the center. If I remember right, your IAC read something like 150 with the key on, meaning it should be open far enough to get air to start the engine. The Reatta does have a clear flood mode, and if the ECM sees the TPS at full throttle, it will shut off the fuel injectors, likely causing the no start. If your TPS is indeed working backwards, pressing on the throttle will bring the reading down closer to the idle position and it will start. Try starting the car with the TPS disconnected. It should start and run, but throttle response may be lousy. This is a very curious situation and if the TPS works as you indicate, the ECM will be very confused and is maybe why the O2 and such is stationary, it thinks it is at full throttle which locks the Integrator and BLM.

I hope Padgett can shed some more light on this one, but I do know there are two different TPS modules used on GM cars (in this approximate era) and the ground is in a different location between the two. It's a long shot I know. The other possibility is the ECM has a problem if the voltage readings were taken through diagnostics before starting the car.

When it comes to balance, I have no idea. Apparently there are different ways of skinning the same cat Greg, I am using an SMC alcohol injection system http://www.smcenterprises.com/ I have had several conversations with the maker of this system and I looked at several others. While originally developed for the GN's, they make a low boost system also, which I am using. The nice thing is there is a small control module for the cabin that allows changes in engagement point (boost pressure) and pump speed to vary the delivery. Mine is set to engage at 5 psi. They also make an upgrade system that varies pump speed with boost pressure, allowing a variable rate of alcohol delivery. This would likely work well with the supercharger. I am struggling a little with the need for more delivery at high load, (third gear), without drowning the engine in lower gears. I rarely do this, but for tuning purposes using a scanner, I have made several full throttle runs from a stop. I reach full 8 psi boost in less than two seconds from a standing start so the variable delivery won't help me. Hope this helps.

I agree. Rain-X or similar works well for rain, bugs, snow and ice. I use it on the side windows too and condesation will just roll off as speed increases. The blades themselves aren't any different but the rubber boot is supposed to shed ice buildup, and it does seem to help that, at least a little.

I know little about balancing. I never understood quite how the different bob weights and such were arrived at. Supposedly our engines are balanced @ 50% and the balance shaft takes care of the rest? I assume it has to do with the "V" configuration for the odd balancing figures? I know the stroker Chevies I have built for my son required additional external balancing in the flywheel and damper. My guess would be the counterweights on a stroker crank may be different or would require the services of a shop to balance it. It's a good idea to check the balance on a rebuild anyway, since the pistons may have a weight difference from stock.

The TPS is way off and it may have odd effects on other things. It looks like it is somehow jammed in the full throttle position or there is a wiring problem. You can remove it and have someone watch the reading while it is operated manually. You can also disconnect it and start the engine to see if the warm idle drops back (the check engine will likely illuminate). MAT temperature looks pretty high, it reads out in degrees C. It looks like the O2 isn't warm enough to get good activity, or it is dead. If the idle is 1700+ rpm, it should get the O2 hot enough that it should show some cross counts? Did you watch the O2 (ED07) for a little while to see if it is constantly changing? It should do so at that engine speed if the engine is warm, and it looks like it was plenty warm.

The lockup speed may vary a little, but around 50 mph for 4th gear is about right (at minimum throttle). It will drop the lockup if you release the throttle close to the idle position. The rpm may not change much when the throttle is released as the "coast" rpm in 4th gear is around 1500 rpm, even though the converter is unlocked. If you step on the throttle again, the rpm may flare a few hundred rpm until the converter relocks. When unlocked the rpm will change more rapidly that the speedo, when locked up, the two will be change pretty much together.

In many applications you can just get a new insert, not the whole wiper assembly. My biggest complaint on the stock system is the blade rubs over screw heads on the trim at the bottom of the windshield and eventually creates a worn spot or distortion of the edge.

Once you get good at it you can enter and exit while driving, pretty much by touch (no inattentive driving ). It is a very useful tool. The touchscreen guys have a small advantage in the availability of some readings at all times.