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PES (QST) SuperCharger - too much of a risk on B8??

Posted: Thu Sep 08, 2016 10:38 pm
by max_b
With the gearbox issues B8 owners are having and the 'unknown' reliability of the PES charger is this combination too much of a 'risk'?
I appreciate both the engine and drivetrain/gearbox will loose any warranty with Audi, so am I asking for trouble as I don't have bottomless pockets?

The car in question is the Red SC B8 on eBay at the moment. I've had a conversation with the owner who has been open enough to say he has already got through 1 flywheel at his own cost and QST who say they are no longer doing new SC work.

From what i can work out the charger on the RS5/B8 RS4 is based on the PES item, who as I understand are no longer around. Kim says he had the same system on his RS5 without any issues. The SC for the B7 had a different set up.

Any of you chaps any thoughts?

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 12:17 am
by RIV
I went out in Kim's rs5 the power and torque was impressive!!!
I was thinking about doing it to mine but as you say I think your going to have G box problems.
Personally I don't think it's worth the hassle, b7 with a charger would be a whole lot more fun, better steering feel with a nice Stick shift.

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 8:55 am
by Graeme4130
RIV wrote:I went out in Kim's rs5 the power and torque was impressive!!!
I was thinking about doing it to mine but as you say I think your going to have G box problems.
Personally I don't think it's worth the hassle, b7 with a charger would be a whole lot more fun, better steering feel with a nice Stick shift.
Like Riv, I was mega impressed with Kim's RS5. The power is mental and the delivery was really smooth
When I went out in it, it was detuned from what it was previously delivering as I thin Kim was aware that the drivetrain etc was at it's limit
Not perhaps exactly a like for like suggestion, but for the value of that SC car, isn't it worth putting a little bit more in and getting a used C7 RS6 ? At least then you keep some form of warranty, and the power is similar

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 12:21 pm
by Surrey Sam
I like the idea of a supercharged B8. For me it would be the best RS4 and perhaps even a better proposition than a SC B7 but the risk element scares me. I've just heard that Audi are now going to replace Gearbox number 2 for me and at a cost of near £15k fitted, it's just too expensive. Don't know why my gearboxes fail, as the car is standard and not abused. I do use the performance but only when oil temps are up to operational levels?

I wonder what Gearbox is fitted to the new R8 V10 Plus/Lamborghini Huracán? As that still utilises an in house Audi DCT one I believe and that car has 610PS with 560Nm, which is a lot more than the RS4 and probably similar level to what a SC B8 RS4 would deliver.

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 12:41 pm
by rspj
Is that 15 k per box or both ? Sam. I don't get time for oil to warm up as near A3 don't get time to warm up

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 12:57 pm
by Surrey Sam
That's per gearbox.

I'm sure that if you just cruise along at 50 to get the temps up, you'll be fine.

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 1:40 pm
by bam_bam
Surrey Sam wrote:I wonder what Gearbox is fitted to the new R8 V10 Plus/Lamborghini Huracán? As that still utilises an in house Audi DCT one I believe and that car has 610PS with 560Nm, which is a lot more than the RS4 and probably similar level to what a SC B8 RS4 would deliver.
Extra power is one thing but the weight is the killer. We've seen this with Audi pairing gearboxes/clutches before, oddly, I think Tiff Needell summed it up best for me, he said [not verbatim] an AWD car with great power is fine but when trying overwhelm the AWD grip with power it costs the drivetrain, add more weight to the car and the clutch will become the weakest point as grip increases (due to weight). Also, the R8 doesn't really run quattro, has a better chassis and it's lighter, thus it might have a better slip dynamic. It will scratch at the road surface picking up acceleration, whereas the B8 bogs, grips and goes, having the drivetrain take on the heavy lifting. All summation of course but worth discussion, ne?
I see it with my car, the B5s run similar (if not more) power and the same drivetrain but their clutch holds the torque, in the heavier/softer C5 the power has to be lower for the clutch holding threshold. Simple physics, really.

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 10:21 pm
by max_b
Thanks for the opinions and views chaps, all very valid and noted. Let's see what happens :thumbs:

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Fri Sep 09, 2016 10:39 pm
by Surrey Sam
bam_bam wrote: Extra power is one thing but the weight is the killer. We've seen this with Audi pairing gearboxes/clutches before, oddly, I think Tiff Needell summed it up best for me, he said [not verbatim] an AWD car with great power is fine but when trying overwhelm the AWD grip with power it costs the drivetrain, add more weight to the car and the clutch will become the weakest point as grip increases (due to weight). Also, the R8 doesn't really run quattro, has a better chassis and it's lighter, thus it might have a better slip dynamic. It will scratch at the road surface picking up acceleration, whereas the B8 bogs, grips and goes, having the drivetrain take on the heavy lifting. All summation of course but worth discussion, ne?
I see it with my car, the B5s run similar (if not more) power and the same drivetrain but their clutch holds the torque, in the heavier/softer C5 the power has to be lower for the clutch holding threshold. Simple physics, really.
Intresting thoughts Bam, I shall certainly ponder over those.

My issues are more mechanical rather than clutch and I certainly don't deploy full power in mine until at least 2nd gear, so probably 35+mph at the lowest? I consider myself very sympathetic to the tranny and use lube before giving it the full fist. Can't believe the DCT box is that chocolate; the car hasn't ever been launched according to the VCDS counter either.

Re: PES (QST) SuperCharger - too much of a risk on B8??

Posted: Tue Sep 13, 2016 7:57 pm
by RS6chris!
Get a C7

Simples