Barry wrote:I took the view that many of the early issues with the M96 engine (porous heads being an example) would have long since manifested themselves and been dealt with. By time a car approaches 100k miles, anything that was particularly bad from the factory would have likely already failed. The remaining cars are likely to be the better ones in terms of original build and how they've been looked after.
Normally that would be the case but with the M96 engine, there is no guarantee at all – an engine is as likely to fail at 10,000 miles as 100,000, or go on for ever whether treated with loving care or relative contempt. It is a lottery but having said that the odds are not as bad as some sources might suggest. What's really bad is that Porsche should never have allowed this engine to gain the reputation it has – and should never have walked away from the problems when they first began to arise.
What Keith meant to say was "I'm sure you're right in your assumptions Barry and I hope you enjoy your new car"
You beat me to it
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
Being reduced to an occasional lurker I have to chip and say. Nice car Barry and why the hell not? Good on you for being objective.
I can see the 996 the entry level 911 for a younger generation. I remember when I was that enthusiastic generation when buying my unloved C3.0 as a 20 something when it wasn't the right car in Porsche circles.
Perhaps soon we will see 996 outlaws appearing shaking up the establishment. I am all for it.
If I can get through my motorcycle track addiction I may join you in 996 or 997 ownership.
Alam
77' 911 Carerra 3.0 'The Beast'
58' 356-A Coupe
55' Chevy
51' AP17
Even to my eyes, they seem ludicrously cheap, and as ever, the driver of prices is the closest alternative. What would that be? A rolling project SC? The days of cheap 964's have long gone. If you bought a cheap SC, odds are high you'd still have to dump a lump of cash in to get it good.
997's now have all the same potential issues as a 996 (heads, linings, IMSB's etc plus later ones need engine strip to replace IMS bearings), plus you've got bore scoring as well, and they are 40% more and upwards.
Cayman? Tempting, but same engine issues again, and if you want a 911, you probably want a 911.
Seems to me that every car already has a full Hartech engine build pretty much priced in before you start.
Of course what I haven't done yet is driven this one on the road. I might have very different thoughts then. Judging by my experience at Brands though, I suspect it'll be pretty decent.
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
Even to my eyes, they seem ludicrously cheap, and as ever, the driver of prices is the closest alternative. What would that be? A rolling project SC? The days of cheap 964's have long gone. If you bought a cheap SC, odds are high you'd still have to dump a lump of cash in to get it good.
997's now have all the same potential issues as a 996 (heads, linings, IMSB's etc plus later ones need engine strip to replace IMS bearings), plus you've got bore scoring as well, and they are 40% more and upwards.
Cayman? Tempting, but same engine issues again, and if you want a 911, you probably want a 911.
Seems to me that every car already has a full Hartech engine build pretty much priced in before you start.
Of course what I haven't done yet is driven this one on the road. I might have very different thoughts then. Judging by my experience at Brands though, I suspect it'll be pretty decent.
Likewise Barry good to hear from you also.
Well I never knew the 997 seemed to also be prone to these same issues.
How much does it cost to have Hartech rebuild a 996 unit? I think its quite wise to plan to have rebuild undertaken. We don't seem to blink when having to have a top end rebuild of air-cooled motor...?
Alam
77' 911 Carerra 3.0 'The Beast'
58' 356-A Coupe
55' Chevy
51' AP17
From what I can gather, £6k plus VAT would get you at the top end of what they offer, and cracked head potential aside (and no doubt they crack test before fitting anyway), would pretty much bomb-proof the engine from there on in.
£6k plus vat would barely buy you enough panels for a moderate early car resto these days, let alone labour paint etc etc. That's before you touch a mechanical component.
That's not to say for a minute they are like for like cars, but if you really enjoy the drive of a 996/7 then to write off that money over, say, four years isn't too bad. Well-rebuilt engined cars carry a premium, plus it seems quite fair to assume these are at the bottom of the curve now, so you might have a bit of price rise to come as well. In all, the maths and the solutions out there are probably now combining to make some people take a second look.
For me, I don't know how it'll work out. I've only driven my 996 at Brands Hatch, and it really, really impressed me. It was so very '911' it surprised me. It was much better than popular forum opinion often suggests. I haven't driven this one on the road, so there might be a let down on the way, but I sort of doubt it. I drove a 997 C2 manual (mines a C2 manual as well) on the road briefly, and really enjoyed it. Again, much more than I expected.
As a naturally risk-adverse person, whether that back-of-mind niggle on longevity will overpower any driving experience is something I'll only know after a few miles.
Mine has suspected IMS bearing issue, which is why the gearbox is out of the car now. I'm mitigating all of the known risks, and will detail the process when I launch a mini-thread on the thing. Before I do that though, I want to take a look inside the engine and make sure my diagnoses is on the right lines and I'm heading the right way.
As for 997, yes, looks like many of the '996' issues have been carried over. I know Paragon (just up the road from me) have two 997 engines with Hartech now, and another two heading up there soon. Ironically, they have had no real problems with the 3.4 996, which at the time was seen as the weakest engine. With the benefit of hindsight though, it seems it wasn't so bad in comparison with the later engines. It produces much less torque low down, and low down torque kills plain bearings, liners and piston coatings. It has full duplex chains throughout I believe, which the later cars don't. The liners are a fraction thicker, and the IMS bearings are a decent sized twin race. Also it has a different liner coating (can't remember which!), which is less prone to scoring than the later cars.
What is very hard to get a handle on though is numbers. There were a lot of these things produced, but how many have given problems seems to be hard to pin down.
Hartech reckon to build an engine a day, week in, week out. If you said they had, what, 1/3rd of the market (probably reasonable to assume, they are 'the' name for these), that's 1000 engines a year being rebuilt in the country. That would include 911's of two flavours (996/7), Boxsters and Caymans. On the other hand, many 996's, many (most?) older Boxters and some Caymans won't even get to be rebuilt and will just be broken. Therefore it's quite feasible that the number of failures nationwide could be, what, 2000-3000? Then you'd have to look at the overall fleet and see where you end up.
Of those of course, many will have been neglected or treated badly. Some will have been mis-diagnosed as needing a rebuild when it was merely a dual mass or engine management problem or whatever. A few might have been O.K. engines but with owners looking for a refresh and upgrade rather than an outright failure.
Finally, you'd have to consider, if a car had done 100k all alright, what are the odds of it failing on your watch. These days, they'll probably only do 4-6000 miles a year, so assuming you do an annual oil change and keep it maintained well, odds are fair you'll be O.K. anyway. The absolute backstop is that £6k+V rebuild.
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
I loved the driving experience of the 996 GT3 (with that fantastic chuckability), so I have often wondered how to get it 'on the cheap' that being the kind of person I am! So if you started with a 3.4 996, what would you need to do to get it to drive like a GT3? I suspect but have no idea, that you might get quite a lot of it with suspension changes. It doesn't need to look like a GT3 (for me), but drive like one even if it is slower. It would need proper seats, that's the other thing that makes an amazing difference.
The cost that would ruin it is if you needed a Hartech type rebuild with their funky liners (or whatever they do).
Any ideas on what to do to the suspension of a 996 3.4 to make it as close to a GT3 as poss?
I wouldn't know how to get a stock C2 closer to a GT3, but I'm sure between Martin and JohnM's 996GT3s, and my bone stock C2 I'm sure we could find a financially pragmatic amalgam! I would suspect coil-overs might be involved. Having not driven a GT3 yet (yet, please note!), I would assume the steering will be different. If that is the case, I'd be very interested to see the differences.
As for the Hartech rebuild, and this is from memory having trawled the net for the last four weeks:
Usual rebuild stuff, good clean of bits, big ends, mains, inspect chains, ramps, oil pump etc etc. All the usual in other words.
They give you the choice of either putting a collar over your existing (bendy) liners, somewhat pulling them back into round (they can be six thou out, hence the eventual cracking to some). Alternatively they make their own liners with the better coating (might be Nikasil?, whatever, a very scuff resistant one), these liners convert the engine from open deck to closed deck, and also are externally ribbed to increase surface area, and therefore thermal transfer. You can also choose to do some and some, as one bank is much more prone to scuffing and cracking than the other. Some people might get collars fitted all round, but perhaps have one already damaged liner replaced.
They modify the block to go to full cooling to both heads and block. Existing design only gives 15% coolant flow to the block / liners, the rest to the heads.
They recommend a lower temperature thermostat, as the thermostat is on the inlet, not outlet of the engine (what happened to German engineering? Accountants, that's what). Therefore by time the standard thermostat has opened, the engine's internal temperature has already reached very high levels.
They fit a stronger IMS bearing, still ball raced, but I believe they leave it open (would need to check this), to eliminate the grease-flush problem. Basically, the IMS bearings fail in part because it's a sealed bearing (with encapsulated grease) running in either an oil mist, trickle or bath depending on conditions. This oil might be near 100dC, and over time hardens the bearing seals, leaving them part open to oil ingress. As this isn't an actual flow, it merely part-displaces the grease, leaving a oily greasy mess inside. It neither gets the protection of grease, or the regular cooling and flushing of fresh oil. The five main solutions are 1) Fit a stronger bearing with stronger seals, 2) Fit a stronger bearing with no seals, to allow constant oil wash, 3) Fit stronger bearing with additional oil feed taken either pre or post oil filter, 4) Fit additional oil feed to existing bearing having removed external (reachable) dust seal, and 5) Simply remove external (reachable) dust shield from existing bearing, having given IMS shaft a wiggle to ensure it's not already falling out.
In addition to above, all of the new IMS bearing kits / solutions include a new bearing-holding spigot / bolt. The early ones had an O-ring groove cut into them, which then acts as a stress-raiser (if that's the right term), which can snap. It's O.K. though, as the all that happens is the intermediate shaft falls off one end of the engine case, allowing all of the timing chains to jump, writing the engine off. I'd guess that if a failing bearing is known for not giving much warning, a failed bearing spigot will give absolutely zero warning. Hence the upgrade.
What else, Hartech have a long-standing relationship with Millers oils, and use those plus Millers coolants with apparently good results on road and race cars.
I'm sure Barry Hart (Baz on the forums, and he's an avid poster), could add tons more, and I'm sure I've not got all of the above 100% right, but the gist is probably more or less there.
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
I'm just trying to verify my comment about the thermostat being on the inlet to the engine, not the outlet. I may have got that wrong, but there are some 'different' ways that these engines are cooled, and the way the thermostats 'read' and react to these temperatures. The conclusion is the same though, dropping the thermostat from 186d F standard reaction time, to 160d F faster reaction time is the recommended route and fit.
Also, Hartech's stabilising rings are designed to pull the liners pretty much back to being round (if not perfect), act as reinforcers to prevent future cracking and finally, drop piston temperatures. They do this in two ways, first the ring has a larger (coolant-exposed) surface area than the liner-only, and secondly, a distorted liner has poorer heat transfer between piston and liner. The rings / collars or whatever you want to call them, help to correct this.
As Hartech say, all of the above doesn't give you an engine that will last forever, just one where many of the original design and quality deficiencies are mitigated (my words, their sentiments).
I forgot to say yesteday, Martin I'm loving your GT3, but one question, what's the road sign to the left say?
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
Well, I Googled Hartech problems, issues, failures, trouble, breakdown, complaints etc, and couldn't find anything. They seem to be solid, and if Paragon use them, they must be good.
I'm sure there are other credible firms out there doing good work, but effectively Hartech seem to have the market pretty much buttoned up. There doesn't seem much to be gained by going elsewhere TBH.
I've not seen their place, or their work, but they've been very helpful on the phone and seem pretty pleasant.
As for the mods in general, the most common one is that IMS bearing, and every man and his dog supply and / or fit solutions.
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
