9m11RS-R - creation of a modern icon - '74 3.0RSR on 9m64RS platform
12-02-2012, 03:06 PM
#871
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The end of day came all too quickly, leaving a very favourable impression from the lessons learned.
The chassis is absolutely awesome. You can really feel the benefit of the combination of a stiff bodyshell with the wide track and phenomenal grip from the wide R888's. Even with no heat in the tyres I would say that the car is already puling nearly 1.5g in the slower corners. Try as I did at Foulston's chicane, even when delierately throwing the car over the left entry kerb (to unsettle the rear suspension) and nailing the throttle to the floor at the apex, at no time would it unstick the back end. The car is simply crying out for another 150hp. The same is true about the other end of the car. The power steering is turn-in is almost telepathic with a GT3RS-like response to steering input, so considering that we are running a 993GT2 evo set up (of which I am more than familiar with as it is the same as my 993RS CS) I can only conclude that the additional bodyshell stiffness from the cage modifications are having a positive effect.
The GT3 gearbox, gearchange and ABS are a hit. The gear ratios from the GT3RS are pretty much perfect even for the temporary 7000rpm limit 964RS engine and the Cup cable equipped gearchange is certainly a benefit to the 993RS rod change as there is no movement of the gate when changing gear under high lateral G. Shame that the same could not have been said about our 964 gearknob which flexed under load, so that will definitely have to be reviewed. My subjective view of the GT3 ABS system is that it has a faster response than the 933RS system. It is almost imperceptible in use, you cannot feel anything through the brake pedal even when hard trail braking up to the apex of a chicane, so that's also allayed any concern over the front suspension scrub radius change from the radically wider track (scrub radius is the offset of the pivot centreline of the front strut with the contact centre of the tyre).
The braking performance was impressive from the carbon pad & 964RS disc/caliper combination. In the morning we had a lot of trouble getting the pads to bed in on a wet track but in the dry it was a completely different story. To be fair I'm not one to be the last of the brakers in a customer's car, so let's just say that there was enough braking effort available to easily exceed the limit of grip braking from high speed at Shell, Knickerbrook chicane and Lodge which are the critical braking zones at Oulton.
Mentioning tyres, I dropped the pressures all day until we stabilised the warm pressure to 33psi front and 36psi rear, at which point the car really started to grab a hold of the dry line of the track. I say warm because even when driving the car like you stole it we could not get more than nominal heat into the treads. The wear surface of the tyres was pretty even so the ballpark geo settings can't be too far out. The M72 nuts were regularly re-torqued but did not move from our pre-day alignment marks.
So I guess that's it for the winter. We've got a hit list of details to deal with before we can sign it off, apart of course from the small matter of the new 9m Race engine....
The chassis is absolutely awesome. You can really feel the benefit of the combination of a stiff bodyshell with the wide track and phenomenal grip from the wide R888's. Even with no heat in the tyres I would say that the car is already puling nearly 1.5g in the slower corners. Try as I did at Foulston's chicane, even when delierately throwing the car over the left entry kerb (to unsettle the rear suspension) and nailing the throttle to the floor at the apex, at no time would it unstick the back end. The car is simply crying out for another 150hp. The same is true about the other end of the car. The power steering is turn-in is almost telepathic with a GT3RS-like response to steering input, so considering that we are running a 993GT2 evo set up (of which I am more than familiar with as it is the same as my 993RS CS) I can only conclude that the additional bodyshell stiffness from the cage modifications are having a positive effect.
The GT3 gearbox, gearchange and ABS are a hit. The gear ratios from the GT3RS are pretty much perfect even for the temporary 7000rpm limit 964RS engine and the Cup cable equipped gearchange is certainly a benefit to the 993RS rod change as there is no movement of the gate when changing gear under high lateral G. Shame that the same could not have been said about our 964 gearknob which flexed under load, so that will definitely have to be reviewed. My subjective view of the GT3 ABS system is that it has a faster response than the 933RS system. It is almost imperceptible in use, you cannot feel anything through the brake pedal even when hard trail braking up to the apex of a chicane, so that's also allayed any concern over the front suspension scrub radius change from the radically wider track (scrub radius is the offset of the pivot centreline of the front strut with the contact centre of the tyre).
The braking performance was impressive from the carbon pad & 964RS disc/caliper combination. In the morning we had a lot of trouble getting the pads to bed in on a wet track but in the dry it was a completely different story. To be fair I'm not one to be the last of the brakers in a customer's car, so let's just say that there was enough braking effort available to easily exceed the limit of grip braking from high speed at Shell, Knickerbrook chicane and Lodge which are the critical braking zones at Oulton.
Mentioning tyres, I dropped the pressures all day until we stabilised the warm pressure to 33psi front and 36psi rear, at which point the car really started to grab a hold of the dry line of the track. I say warm because even when driving the car like you stole it we could not get more than nominal heat into the treads. The wear surface of the tyres was pretty even so the ballpark geo settings can't be too far out. The M72 nuts were regularly re-torqued but did not move from our pre-day alignment marks.
So I guess that's it for the winter. We've got a hit list of details to deal with before we can sign it off, apart of course from the small matter of the new 9m Race engine....
12-02-2012, 03:15 PM
#872
Burning Brakes
Nice write-up Colin, and some pretty good pics too 
It'll be interesting to read what you feel about the chassis once the new engine is installed
It'll be interesting to read what you feel about the chassis once the new engine is installed
12-02-2012, 04:33 PM
#875
What an absolute stonkin machine!! Nice right up of the first rundown of this unique car..well done all at 9m
Ps..we have that top secret engine to go yet,can't wait...
Ps..we have that top secret engine to go yet,can't wait...
12-02-2012, 05:05 PM
#877
what happens from here? erik lives in malaysia, right? is the car being shipped over, or waiting in the UK for the new engine?
12-02-2012, 09:01 PM
#879
Formerly turbotwoshoes
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Incredible!
Colin, thank you for sharing. What a car! It looks so right..and with custom loom work and no problems.... you have quite a shop! You are to be congratulated on a job well done! It is so good to see the restrained smiles of the owner and his son...especially when they are mounting the Go-Pro on the window... I patiently await the footage!
Even my wife commented that the car is too quiet... so that is a really good sign!
As always, waiting on more... Jack
Even my wife commented that the car is too quiet... so that is a really good sign!
As always, waiting on more... Jack
12-03-2012, 08:25 AM
#882
Professor of Pending Projects
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What an amazing build! The level of detail, the amount of hours pour into finishing the car to this level. Just amazing! And we got to see it via the updates provided and the photos. Thank you so much for taking the time to share the progress and final product.
12-03-2012, 12:59 PM
#883
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12-03-2012, 01:23 PM
#884
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I must say a quick thank you to Bookatrack for organising the trackday on Saturday. As usual it was well organised and even though it was attended by a wide performance spread of cars & drivers (including novices) the driving standards were impecable Aside from an unfortunate incident between a VX220 and the tyre barrier at Old Hall (the first righthander at the end of the start/finish straight) we had very few stoppages and the day went very smoothly. As part of Bookatrack's sevice they organise professional photographers around the circuit, here are a few shots from Erik's collection.
Just in case you are wondering why there is an Audi S4 Avant out there, that's my everday motor being pressed into service on the familiarisation laps at the start of the day. Given the conditions at that time I think it could have been the ideal weapon of choice! I must also apologise that most of the photos have me in the driver's seat during the early sessions when I was trying to show Erik the correct racing lines for the bends. Given that Oulton Park is notoriously an unforgiving track should you get it wrong we must have done something right because not a lot passed us and Erik pretty much had the lines nailed by the end of the day. Nice one.
Just in case you are wondering why there is an Audi S4 Avant out there, that's my everday motor being pressed into service on the familiarisation laps at the start of the day. Given the conditions at that time I think it could have been the ideal weapon of choice! I must also apologise that most of the photos have me in the driver's seat during the early sessions when I was trying to show Erik the correct racing lines for the bends. Given that Oulton Park is notoriously an unforgiving track should you get it wrong we must have done something right because not a lot passed us and Erik pretty much had the lines nailed by the end of the day. Nice one.
