3.0 16V engine mods, etc

[Thom]

Just got back from a 600 mile drive, 90% of which on the highway, and can confirm the initial obervations that the larger compressor provides more instant torque at throttle tip-in, which makes the car a friendlier and smoother drive under low loads/vacuum than with the previous turbo and this results in better fuel efficiency as cruising at 150kph / 95mph in 6th has returned a respectable 29.5 mpg (imperial) or 24.5 mpg (US) or 9.6L / 100km. The engine picks up in 6th down low a little better than with the previous turbo. There is just more meat everywhere down low, though fat-free meat obviously as it is still not a large NA V8. These small gains are very appreciable in real world driving conditions though.

[333pg333]

Sounds like a worthwhile change then Thom. Is this with the new clutch?

[Thom]

This is still with the 4 spring 930 clutch disc.

Yes, so far I think the larger turbo was a worthwhile change. Honestly on the first drive I was disappointed with the loss of "response" and thought I would move back to the previous turbo sooner than later but the more I drive it the more it grows on me and how smoother the engine runs and how some relevant figures such as EGT have evolved in the right direction now prevail over the loss of response. It just took me a little while to adjust to the larger turbo and how it performs. Even if I cannot run the engine with "high" boost yet I think it is still a very good balance between response, torque and power, although in a different way than with the previous turbo, suggesting planets can align in different manners after all!
I took another car to its periodic technical visit this morning and although it makes a comfortable 500 bhp with a very responsive and high revving NA engine, my immediate thought at the wheel after the long drive with the 944T last week was how deceivingly fast, partly due to the low-ish compression ratio, the 944T felt in comparison. Effortless is perhaps at this stage the term that defines it best.

[Thom]

Pleased to say my car has brand new sills. The rust dated back from before I bought the car but I found an officially retired professional body worker who agreed to help me replace them so this is done at very long last. Had the sills repainted in Grand Prix white to match the CS seats so that means there are now 3 different shades of white on the car but nevermind. The plan is to have it fully repainted in Grand Prix white "one day". In between drying sessions between primer, gravel protection layer and final paint we found the time to fit the new clutch disc from South Bend. I can't say if it holds the torque yet as the first and only full load acceleration on the way back home caused an intercooler hose to pop out and since the roads were wet anyway I didn't take any more risk. Crashing a car that just went through significant body work repair would have been a little embarrassing.

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I also helped my friend who provided the room for the work on my car replace the clutch on a customer's 997 turbo. He found a good spot to answer phone calls.

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[ROB III]

Nice Office!
Kudos to the decorator.

[Tom]

Paint work is looking good! How is the engagement on the South Bend clutch? Smooth as stock? I worry a bit about my recommendation because it looks like a more aggressive disk than the one I had.

And, at the risk of annoying you....

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[Thom]

Engagement is nearly as good as stock as long it's not asked to work for too long in stop start traffic as it begins to be a little juddery when hot. What is not so good though is that the biting point is way higher on the pedal even after lowering it to the maximum possible. This is a PITA on a car where the biting point was at the same height in the 19 years I've had it and I've been struggling to adapt to it. Could the supposedly less progressive nature of the new disc give a false impression that the biting point is at a different height?

No room for one of these rods as the sleeve at the IC inlet is too short. This is the first time this happens since fitting the custom intercooler and I suspect that's because ambient damp goes through rubber on long periods of letting the car sit unused. It should be fine again after degreasing the connection.

[Boostfeen]

New Grand Prix white is looking clean let us know how she looks on first drive after put back together Thom

[Thom]

New Grand Prix white is looking clean let us know how she looks on first drive after put back together Thom

Well, there is a picture here, which @Tom made me the honour of using for the latest banner - I bow to you Sir but the car is not worth it!

The car has been out only 3 times since picking it up with the fresh sills from my buddy 3 months ago, each time in poor/wet weather (to pick up stuff for other cars that have been taking way too much of my spare time lately ). The new clutch is still difficult to adjust to, very on/off, and the car has definitely lost its easy-going, drive around/shopping trolley abilities but trying to see the glass half full in that the clutch now demands a level of focus in line with the straight-line performance. Jumping back into this car after enjoying others with far less punch is always a surprise and opening the throttle to run at only atmospheric pressure whilst casually cruising in 5th brings the speed from 60 to 100 mph in the effortless and comfortable manner of a jet about to take off, suggesting the larger turbo flows just what the head needed to show its true colours even at the lightest loads, making the car not only a rear tyre executioner but the ultimate long distance cruiser. It may sound like a hyperbole but it really creates its owner weather and you better be on it when you open the tap.
Upgrading the fuel delivery is on the back burner though I may upgrade from the 044 to the new pump when I have a few days off at the end of the month, as it really is an easy job.
Thanks to all who still have an interest and sorry for not spending as much time on this car as it deserves and post interesting updates, but sorting the fuel delivery may be mostly needed for a clean glory run on the dyno and I have a feeling bottom end bits may kiss the shop floor if pushing the turbo above 26 psi where it seems to perform best.

[ROB III]

@Thom
SIR, with all the work you have done and shared with photos along with trials and tribulations, you clearly belong on the banner.
Clean, fast, well-engineered, being used as it should be without the restrictions in the US, its a great example of what the platform can become with time.