JFP in PA

A lot of people use the Optima AGM battery, myself included; the Oddessy has been a bit more problematic due to low CCA output, particularly in colder weather (most of the so-called "racing bettery' manufacturers use a cobbled up cranking amp test designed to hide the battery's lower output). Some have also noted lights dimming when the audio amp kicks in, another sign of the unit's lower capacity.

Optima does not suffer from any of these draw backs.

Clean engine oil is fine, dielectric grease would be better.

There is a fair amount of truth to your proposition; there is actually a methodology that claims to have identified the harmonic frequency trace of an IMS bearing going bad using an external sensor and a recording oscilloscope device. This concept was written up in a publication some time back.

Unfortunately, there are flaws in this approach. The measurement technology requires some pretty sophisticated equipment (read expensive and not very portable), and it generates a fairly complicated data set that requires technical interpretation to determine the bearing is bad. Add to that the simple fact that by the time the bearing is either making bad noises, or harmonic frequency traces, it probably has already filled the engine with the typical fine metallic grit that a dying IMS creates, eliminating any chance of saving the engine without a complete tear down and rebuild.

Raby’s “Guardian” system would probably have picked up the IMS decay earlier, before it had done enough damage to be detected by either sound or harmonics, and more critically before in rendered the engine in need of a total tear down…………..

Did you refill the system while it was under vacuum (preferred OEM method), or pull a vacuum after filling the system at atmospheric pressure? If it was the latter, you may still have some air in the system.............

Hi Everyone, Looking for a reputable engine rebuilder for my 99 c2 3.4, I believe engine has a cracked cylinder or sleeve , was actually ready to pull the trigger and have Motor Meister do the rebuild and big bore to 3.8 but checked into their past and found alot of complaints and unsatisfied customers. Im located on east coast (NY). was also looking for some performance upgrades. Engine is out of car and ready ! Thanks

Without a doubt, you want to talk to Jake Raby at Flat Six Innovations; Jake is probably the preeminent M96/97 engine builder and a real stickler for detail and quality.

http://www.flat6innovations.com/

And be happy you bailed on the other guys, their reputation is well earned………..

Works every time.............

We have looked that this a couple of times, and while we never ended up doing one (too costly) I have talked to a couple of shop owners that have done them. They are time consuming, expensive, and simply not worth the effort. You either have to source most of the hardware from Porsche or a wrecking yard, you end up with only a few items that are resell able, and the value of the car becomes diminished because of the transplant. In the end, the owners of the cars swapped over came to the conclusion they should have just sold the existing car and bought one the way they wanted it...............

Can it be done? Sure; but the question becomes “should it be done” as seems it ends up with “the view not being worth the climb".

Hi all. Currently working on a 2.5L engine. The engine was making a clicking noise but ran. Pretty sure we've nipped an IMS failure in the bud. Gonna replace the IMS. Found metal flecks in the oil filter. Going to open the engine, clean it up and replace anything that's damaged.

Need the proper tools for locking the cams in place. I think its tool 253 but I'm not sure where to find it. Any ideas what tools are needed?

Several firms sell these, LN Engineering (they make them, Flat Six Innovations (Jake Raby's firm), and Pelican Parts. Do a search...........

The best stuff for lubricating the noisy rubber bits on the top used to be a now discontinued BMW product named “Gummi-Pflege”, which is really just a type of thin silicone grease. You can probably do just as well with spray silicone and rub it in.

Look at it as a long term insurance policy and it won't feel so bad...................... :thumbup:

Mike is spot on, the coolant tank sometime starts leaking only when hot because that is when the system pressure is at its maximum. You can hook up a pressure tester and run it while the engine is hot, even taking the system over the 18 PSIG normal running level to trip the leak. You can also add some UV coolant dye to the tank and run the engine until hot before looking for the leak with a black light source which usually very quickly points out the problem areas.

Mike is also correct on being very careful about using the car in this condition, if the tank or another component suddenly completely fails, it will strand you and could overheat and take the engine with it; caution should be your focus at this juncture.....

JFP...can you say ~650HP... The only part of the fuel system to fail is the rubber U-shaped hose...it has been designed out by Porsche, so I'm guessing I'm not the only one with issues. In any case we have modified the hose length and installed a high pressure fuel submersible hose....should do the trick.

Pardon my repeated questions, but why do you need so much pressure? I've seen these non-DFI engines go big HP the dyno with lots of fuel volume (larger lines, bigger injectors, etc.), but without increasing the pressure. If you can find DFI lines that are the correct size and shape, they would work as the DFI operate north of 1,000 PSIG........

You can lead a horse to water, but if you hold his head under until the bubbles stop coming up........................ :eek:

As we have already had this conversation, I will repeat what I said earlier:

$9K+ is a lot to risk on reconditioned rods with 100K on them, and I personally would not re use quality aftermarket rods with that kind of miles on them.......................

Why are you trying to run such a high fuel pressure? Everything in the fuel system is rated for the factory 3.3-3.8 bar pressures, so I am not surprised things are not holding up when the pressures are nearly 46% higher.........

Basically take everything apart just like you were going to pull the IMS, but because it won't come through the case, use a small pick to pull the rear seal off of the bearing, then reassemble everything..............

I don't think so - it doesn't seem to be coming from the tires - more centrally located. Tires/wheels shouldn't cause vibration issues at idle.

Nor would anything in the drive line; sounds more like a mount issue.

How about a tire or wheel bearing issue?

In order to correct the journal size, you would significantly alter the journal end weighting, which could become difficult to dial into the crank counter weights. The overall rod and piston combined weight is critical, as again it plays into the crank counter weights as well.

Having raced various Chevy engines myself, I can honestly say there are some rods that were pretty good, and others that were total rubbish, so a lot depends upon what the rods were for.

The stock Porsche rods are "adequate", but not great; any time rebuilding and upgrading a Porsche engine, we went with after market stuff; R&R and Carillo makes some very nice forged steel units, or you could jump for the big bucks and go titanium.

Battery maintainers are designed to keep good batteries at an optimum charge state, they are not designed to recharge fully discharged batteries; they simply lack the amperage out put to do it. That will require a more substantial unit.

Suggest getting the battery fully charged and test (load test) to be sure it is OK. If it passes, the new maintainer will keep it in good condition.

Depends upon many factors, realistically about 4-6 years is typical.

All Porsche's have a slow (40-60 mA) current drain due all of the electronics; over time, it runs the battery down. Try recharging the battery, but then have it load tested as this condition is sometimes fatal to the battery. Then go out and buy a good battery maintainer (not a trickle charger) such as the Ctek units, and when the vehicle is going to sit, plug it into the cigarette lighter and it will keep the battery(s) fully charged.

JFP thanks for the response, If only it were that easy ..... not sure if you've removed the alt before or not but I followed the instructions as posted. I also went a step further and went to the local Porsche dealer here in Toronto, as luck would have it a tech was taking an alt off a 996. He walked me through the process and explained how seized the bushing can become and to be carefull not to break the alt housing pounding on it with a hammer. The bushing on my car was seized solid after 11 years and 125,000 km including Canadain winter driving. The point I was making, and why I was sharing my experience is to make it easier for others attempting this job. Heating up the aluminum housing allows you to easily push the bushing back instead of pounding on it with a hammer and potentially breaking the housing ......

I own an independent shop, and we pull out a fair number of M96/97 Porsche alternators just about every day; we have never had to heat up an alternator case, or pound on it with anything. Loosening the bolt and giving it a tap or two is all that was necessary in all the years we have been doing it; the bushing only needs to move a thousandth or two for the alternator to come right out. I have no idea why you had such a problem, but we never have seen the need to risk heating up an alloy housing or beating on it.

By going earlier, you get to correct the IMS issue, versus a few HP for considerable potential G&A (grief and aggravation)……….. All depends upon where your head and wallet are at.

Unknowns: Are the journal and pin bores the correct diameter and width? Is the the length correct? Do the journal ends clear the crank carrier and cases? Is the weight the same or less than the OEM rods?

If the answers to the above are mostly "No", it would be cheaper to go with quality aftermarket stuff. Not cheap, but well made and they at least fit..............