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Lightweight flywheel and clutch

Well, Chrs and Ash at Pie Performance have the engine and box out of the car now.


The cause of the vibration I spoke of appears to have been caused by poor fitting of the replacement clutch just before I bought the car last September.(which cooked the release bearing and clutch fork)

We have got a complete OEM Porsche 4.0 GT3RS flywhel and clutch set up to retrofit and go single mass with an EVOMS underdrive auxiliary pulley.

https://www.facebook.com/2453365354...254911062572/1156254734395923/?type=3&theater

https://www.facebook.com/2453365354...254911062572/1156254701062593/?type=3&theater

Whilst the motor is out, we are replacing water pump and fitting low temp stat, welding the cooling pipes an fiting titanium exhaust studs. As a further precautionary measure, the header tank and main coolant pipes to rads are being replaced.
We are refilling with Evans waterless coolant to negate any corrosion issues in the future.
 
Duplicate post
 
2 comments / questions:

Why the LTT? Are you in Dubai or something? I've never seen the GT3 waiver from just over 80 even on a hot day on track after a solid hour of running. Actually, thinking about it, I have. I once got stuck in a traffic jam in one of the long tunnels in Brussels in the summer. Eventually the temp gauge went past 120 but the car still ran perfectly & when I did get outside again, returned to normal with a few minutes.

Evans? Corrosion is non-existent if the correct coolant is used in the correct ratio with water. Evans has a heat conduction coefficient worse than water so you are actually more likely to experience cooling problems, particularly localised ones in the water jacket where the heat is actually generated. The thing is, your temp gauge won't register it as it's a) too far away & b) smoothed so you never see peaks. Therefore you risk a ring or piston failure & you'll never even know what caused it.

Evans is a fix for old British stuff like Jags, MGBs & Stags, not a modern highly tuned race engine. If it was so fantastic, all the race teams would use it. Hint: they don't. It's certainly a nice little earner for the dealers who champion it though...
 
Thanks Nick for your absolutely relevant questions.

LTT, probably an overkill, but have had good results on my 996 C4, which has had one fitted for 15000 miles and including a 2000 miles around a very hot 34 C South Germany last August, where the gauge always sits just below the 80C when travelling under normal conditions, probably a piece of mind thing, I guess which allows the coolant to start flowing to the rads at a few degrees lower temp than a 80C stat. I understood, higher temp stats were to keep emissions down, but may be mistaken.

Evans, I had one of the quick release hoses (near side rear) blow off the GT3 at Snett on a Trackday, now whether this was caused by the previous owner's clutch change and the mechanic not seating the connector properly during the reassembly, or excesive pressure build up in the cooling system, I can only surmise.

Now this all happened, luckily, on the start finish straight , so did not experience the heart stopping experience of the rear tyres getting soaked in a turn and watching the world rotate, but nevertheless, stopped track proceedings for a good half an hour, and left me with a lengthy fix in one of the pit garages, before we got out on track again.

My good friend Bob Dance, from Classic Team Lotus was with me, and we both agreed, being able to wire lock these quick release couplings in place would be a good idea, but were unsure how to go about it, short of replacing them with the aerospace type of couplings that Lotus use on their F1 cars.

Notwithstanding this, I feel that reducing the pressure build up in the cooling system of the Mezger engine cooling system is not a bad thing, recognising the known issues of the motor to hose connections, and of course the faff required to replace virtually any of the myriad number of hoses and connections on our cars which are subject to cyclic expansion and contraction due to coolant system pressure changes

I must admit, that I havent had any concern with the overall cooling efficiency of the GT3 system, but want to increase the reliability, by a degree of preventive maintenance to the power unit, whilst it is out and everything is accessible/ replaceable.

I understand and agree with what you say regarding lower thermal conductivity of Evans versus water/glycol, but feel it is a worthwhile experiment; furthermore, if my piece of mind is increased, (knowing that the coolant pressure is not increasing dramatically) and the likelihood of a hose blowing off is reduced when at the top of a mountain pass in Europe in August, then it is something I am willing to have a go at.

I appreciate your cautioning words of technical wisdom, and, as an engineer, it certainly has had me pondering the decision, and if it doesnt work, then, I also will be eating these words and accept the "told you so's", if it all goes horribly wrong. :worship:
 
I hear you but still feel you are trying to cure a problem which doesn't really exist in the way you think it does.



As you can see in the above video, I had a hose pop off at the junction of the two hard pipes under the car at the rear a while back at Donington, in the chicane. After that I decided to replace all the hoses everywhere on the car. That's a lot of hoses & a lot of work to get to some of them. It emerged from that exercise that many of the hoses had shrunk in length significantly, including the one that failed; some were found to be just hanging on via their clips.

Given that 80% of them are hidden, to my mind that is the real danger as these cars get older. The lowish pressure in the cooling system isn't a real problem, you can squeeze the hoses easily when the car is up to temperature.

Assuming the cooling problems of the M96 engine are applicable to the Mezger is a mistake; they bear no resemblance in the liner & water jacket design. Running the engine too cold will result in more fuel being burnt, it's an efficiency thing rather than pollution per se.
 
Hi Nick, have been pondering this all day and have decided to follow your well thought out advice and stick with standard stat and water/glycol as coolant medium.

Thanks again for the time and effort putting forward your experience and makes me appreciate the benefit of being part of a forum with guys like you !

Chris at Pie is already planning to replace the two quick release hoses, feed and return, which I understand caused both you and I moments on track in the past.
:thumbs:

Is it worth worrying about the two plastic angle tubes that bolt to block ( I believe Sharkwerks offer a stainless replacement)? Are there any UK suppliers for these or is it order from States only?
 
Stuart Mackay said:
Is it worth worrying about the two plastic angle tubes that bolt to block ( I believe Sharkwerks offer a stainless replacement)? Are there any UK suppliers for these or is it order from States only?

Hi Stuart

The only pipes you need to worry about are the glued water pipes that fit into the castings. While the engine is out, it's worth doing the RSR breather mod (996.107.491.91 - releases a further 8BHP) & replace the fuel filter, both of which are dead easy to do with the engine out but a pig / impossible with it in.
 
Thanks Nick, Breather upgrade added to job list, the RMS was found to be weeping slightly, so that will be replaced, are there any part number recommendations for upgrades on RMS?
 
The one from the 964 has always been fitted on my car & is my engine guru's preferred seal.
 
Nick, the guys at Pie tell me that the 997 engine is different to the 996 and that the 996 breather isnt available from Porsche at the moment any other suggestions?
Thanks
Stuart
 
Yup, I'd forgotten that it's a 996 only mod.

My suggestion is to get it built & back in the car. Then enjoy "summer" in it!
 
Thanks for your help, just waiting on Porsche to suppy replacement header tank and then we are ready for take off :thumbs: :worship: :thumbs: :thumb:
 
Car is back on the road and the throttle response is amazing with the lightweight RS4.0 flywheel/ clutch and RS auxilliary pulley set up. The clutch action is very smooth and no heavier than the standard set up, there is a bit more transmission noise transmitted to the car, but you have to listen out for it and it is nothing that Radio 2 would not hide. :eek:

Whilst the engine was out, we fitted a new 964 Rear Main Seal, fuel filter, new water pump, replaced all rubber and aluminium water hoses, the expansion tank, as well as TIG welding all the bonded water pipe connections to the engine.

Pie Performance near Lavenham in Suffolk did all the work and a super job they made of it all too, see below:

https://www.facebook.com/search/top/?q=pie performance
:thumbs: :thumbs:http://www.pieperformance.co.uk/
 

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