2seater

I used one of those years ago to input a portable CD player in my stock '90 radio. Never gave a problem although the radio was eventually replaced with an aftermarket Pioneer.

You have to look at the pump to see about the ethanol content. In my area, and probably nationally, the fuel must be labeled that it contains ethanol. Some stations do offer non-ethanol premium in my area, but I was told the best pure gas octane available here is 91 and the ethanol blended premium would be 93. My experience has been a 3% mileage reduction with the 10% ethanol blend. In the past, before the widespread usage of ethanol blends, my cars experienced the best mileage with 87 octane. Excess octane usually slows down the ignition process somewhat to allow for higher compression and/or greater ignition lead, which usually makes the engine feel smoother, but it wasn't the best for fuel mileage. Now that ethanol blends are almost unavoidable, the experience has changed.

It won't hurt the car at all to drive with the cam sensor out. It may idle a little rougher if the ECM guesses wrong on the injector sequence every time the engine is started but overall performance will be just fine.

The overbore shouldn't change the fuel requirements dramatically. It did add a few cubic inches but only a small percentage of the engine size. Have you checked the fuel trim values and O2 sensor cross counts in diagnostics? If you had one vacuum leak, there may be others? The other possibility would be a leak in the exhaust in any of the piping ahead of, or close to, the O2 sensor. Raw air entering the system may fool the O2 sensor. The note about the engine still being in the process of running in probably has a bit of merit also. Lastly, having the injectors cleaned, or traded for rebuilts, can be done for a reasonable cost from several online vendors. A more expensive alternative is the new style Bosch injectors with a better spray pattern which seem to have a positive effect on mileage. There has been at least one thread about them. You can do a simple test of basic injector operation by cycling them on and off from diagnostic overrides. The engine should idle with the IAC unplugged and cycling the injectors individually will give a crude idea of the balance by watching the rpm drop.

Does the transaxle have the same final drive ratio to the original? My stock 2.97 1990 shows 2000 rpm @ 72 mph in lockup. A good active O2 sensor has a substantial affect on mileage.

I was pulling down my spare engine that I rebuilt some years ago. At that time it received the "new style" chain tensioner. It now has about 35k miles on it and I found the tensioner to be completely worn away on the lower third, just short of metal to metal contact. The shoe of the new tensioner has void areas on the back and once it wears into the void, it looks like it will wear very quickly. The photo shows the original style tensioner from my '90 engine with 92k miles on the left and the new style with apprx. 35k miles on the right. My unscientific test with a spring loaded center punch indicates the new style is softer material. I tried the old tensioner back in place and it looks like it would go another 92k miles with no problem. Has anyone else seen this sort of wear?

This sure sounds like what I went through this last summer. Car would start and run fine for various amounts of time, but would quit without warning. It would always restart after some period of time and run like nothing was wrong. I couldn't believe it was the crank sensor because they usually stay broken when they fail. All FSM tests came back negative but could never find anything else amiss. Replaced the crank sensor and ran flawlessly ever since.

Who knows if the fan calibration is off? Easy to check visually for damage also. I have had the front fan lose a blade and it vibrates, badly.

Is this possibly related to the odd "wobbles" of the crankshaft or has that been resolved? I would think rpm would have an effect if so. What condition are the mounts and exhaust hangers? Metal to metal contact will transmit all sorts of odd sounds or feelings. I tried a solid upper torque strut mount but it was intolerable.

I was going to stay out of this too, but I was dismayed by the tone of the retorts to Peter's message. Apparently there is a lack of understanding that we are guests here and what the moderators function is. A public admonishment seems the proper means to let everyone know without pointing fingers. I can't think of anything else to say without getting personal, but I do want to thank Peter for his past and present help.

How does the crank damper rubber look? It shouldn't affect the shutter wheel for the crank sensor but the outer ring could wobble if the rubber is deteriorating. Checking the thrust end play is a good point. Fore/aft movement could give the impression of wobble.

I have not done so but it does seem possible although it doesn't appear to be listed under in-car repair. The front cover with oil pump would have to be removed also. The pistons would have to be pushed up so the crank throws would clear. Since this a sort of "Y" block, I would think pulling the caps would be no fun either. Wasn't this crank ground or polished? If so, it seems odd that substantial runout wasn't noted at that time. Was the crank installed and spun without the rods/pistons attached? Was it smooth or tight/loose as it turned? Padgetts suggestion of a dial indicator on the snout is a good one, prior to all the disassembly work. A cracked flexplate is is a good possibility also. Even in a non-kicked situation, this does happen on occasion. I know you aren't afraid to go the extra mile, but I think you may be breaking new ground.

The bubble isn't actually mounted there. It was expedient to simply set it in place with the mounting tang towards the firewall and vacuum port to the bottom. It stays there quite securely and has been there for many years. The stock exhaust "headers" actually flow better than appearances indicate and are surprisingly even in flow. They can be ported and the rear outlet IS a mess that can be improved. The pipes at the ports are actually 1.375" i.d.. Conventional wisdom for a zero loss exhaust is 2.2 cfm required per horsepower and flow rating is 115 cfm per sq. in. Too big loses velocity, decreasing the draw, usually costing some torque output.

Do you have the black plastic cover for the area forward of the radiator? Without it, a small amount of the cooling air can go over the top of the radiator support, rather than through it. Dropping the lower black plastic air dam, a 1/2" or so, does also improve airflow slightly. I have experimented with this a bit with pressure probes ahead of and behind the radiator. Nice looking detail work.

Uh, the knock sensor works fine. I must have taken my stupid pills by mistake. The FSM says to check for knock signal with the engine idling. Some of the other tests, with the sensor disconnected, can't be done safely with the engine running, so, I ass-umed it could be tested with the ignition on, engine off. Not so appaently.

I agree completely. The chip is wrong for the application. Probably stupid to test without changing the chip or injectors, but snow is coming on and I wanted to see if it worked at all before winter closes in. The lack of knock sensor is the show stopper now.

I appreciate the encouragement. I do know of the MAF limitation but at this poiint, I don't believe the air flow is much, if any, above that level. I have recorded the entire run and have examined it closely. The indicator actually drops slightly just before the shift, assuming it is getting beyond the comfort zone of the mild cam. The piping is all ceramic coated and the pipe under the T/B is after the turbo so a fair amount of heat has been removed by the turbine. My biggest concern at this point is the lack of knock sensor response. I do not have any more stock chips but I do have a couple of turbo calibrated ones that fit the ZIF socket. It is the only variable that has not been changed.

Update on the turbo installation using only the front exhaust to power the turbocharger. The turbocharger is an essentially stock Garrett T3 from a 4-cyl. turbo Thunderbird. The only modification is a custom exhaust outlet to connect to the stock rear manifold. I am also using an external wastegate rather than the standard internal design, although tests indicate no wastegate is required. Installation shown in signature. The cruise control servo was relocated to the strut brace to make room for the wastegate but would not be necessary without a wastegate or use the stock internal one. The vacuum reservoir was relocated many years ago for the previous installation. Air filter shown is too small and may contribute to the low boost. More tests will be needed to determine. The short test run shows seamless power delivery, although boost is somewhat lower than targeted, hence the lack of need for the wastegate. Maximum observed boost was (4) psi just after the 2-3 shift. This was tested using the stock chip, injectors, 195* thermostat and 91 octane. A screen shot is shown below from near the 2-3 shift point. The air temperature F. shown is from a modified stock sensor located inside the MAF housing. This is with ambiant air temperature of 37*F. and this installation is intercooled. It shows the injectors are nearly static and the exhaust is lean, which is to be expected using the stock injectors and programming. I really need a wideband O2 to tune properly but funds don't allow at this time. The questions are these: The MAF reading equals approximate hp. of 220+, but that would only make sense if the normally aspirated level was closer to 180hp. or, the small 2.25" inlet pipe "fools" the MAF into thinking air flow is greater than it is. Perhaps it needs a short section of larger diameter to not bias the flow toward the center of the MAF? Note: the MAF/throttle body is from a TPI manifold and sensor reads in the same range as the stock LN3 MAF. The engine internals are bone stock with 93k miles. I do have a high flow cat. and 2.5" Dynomax ultraflo muffler. The second question is more involved: I cannot get any readings from the knock sensor (very important in a turbo install). I have tried two knock sensors which both show resistance values near the middle of the FSM range. The connection from the ECM to the sensor shows 4.95 volts, again near the center of the expected range. One of the knock sensors is more sensitive when tested for voltage output when istalled in the engine using a VOM from sensor to ground and tapping the engine block. I tried two different ECM's but only the stock chip has not been changed. Is there anything that can go wrong that could "take out" the replacement chip I received from J. Finn.

If it is the aluminum TPI manifold I don't remember there being a gasket either but there was residue of some sort of sealer as Recian suggested.

Nice looking work. I have not checked the water temperature with a mechanical gauge or IR gun but I don't get any indication the engine is hot even with an intercooler, oil cooler and trans. cooler directly behind the grill. These items get all of the air first and completely cover the grill area. I will have to check with a second means to see if there is indeed a discrepency between indicated and actual. I do have a new water pump installed but the drive is all stock. The ceramic coated exhaust system under the hood does reduce the "feel" of heat under the hood.

No, there is no calibration to the screen ahead of the sensor. It only cares about reasonably smooth, laminar flow, across the sensor. Some have had success with no screen at all, which reduces restriction, but that requires a fair amount of smooth straight pipe ahead of the sensor. Many of us have swapped sensors without incident, however, there is a different calibration from one engine series to another. Best to stick with vin code "C" sensors unless you have the ability to check the calibration. In a pinch, it looks like the sensor from a 3300 engine will work although the calibration is slightly different. Given time, the ECM may be able to adjust the fuel flow to the MAF reading even if slightly out of expected range. From the testing I have done, no two sensors read EXACTLY the same.

Yep, the roller trunnion rockers I looked at look like those, sans the polished finish. I am not quite sure what the extra bar is? A stud girdle over the top or a new support to bolt them down tight like the originals? In any case, the Aussies are very creative and have many models of Holden spec. variants of domestic GM models, generally higher performance. I looked over a new police car at a dealership. Labeled as a Caprice on the trunk with wide steel wheels and dog dish hubcaps. An LS engine under the hood (6.2 liter?). Mean looking car. I looked over the build sheet and it was over 60% Australian content with several percent more from Mexico and Canada leaving about 13% U.S. content. It looked like it meant business, (was going to a local small town police department), but it struck me as odd that it was essentially a foreign car. Maybe not so odd with worldwide sourcing of parts. Holden Commodore SS, maybe, for almost $50k.

The short answer would be yes, you should get slightly better mileage. Driveability will be unaffected. Do you have unadulterated 87 octane in MN?

I looked into retrofit of those roller trunnion rockers several years ago, but there are a couple of issues. The stud size is different (smaller) and the offset of the pivot point appears to be different also. The hole in the cross shaft can be made larger, after dissassembly, but I couldn't solve the rocker geometry issue. Can also make the rocker adjustable but the rest didn't work out. The '88 cam has more lift and duration, but nothing to write home about. Still pretty mild but it does feel somewhat stronger (very subjective, I know). Air flow indications through the MAF do seem to indicate greater airflow. Easy to check for anyone that has both models and compare.

I received mine on Wednesday in perfect shape. Thanks for the quick service.