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Hi guys,
beeing disappointed with power/weight ratio of my RS4 i decided to boost power with supercharger (intercooled 0.5-0.7 bar) . Anyone here has experience with it? I wanted PES (quite OK price) but I read some terrible experience with this firm and I cannot afford buy $hit. MTM is out of my budget. APR doesn't have final version or do they?

Benefits
+power boost.
+quite rare car

Cons
-problem with selling (not original car)
-price
-reliability

Any idea? Which brand? Price? Risks?

Im curious: Why is everyone from PES banned on several forums? Are they evil boys?

BR

Garry

I've heard nothing but bad things about PES. A guy from the A8/S8 forum is fitting a Jaguar supercharger to his 4.3 V8 S8 though. Just waiting for him to unveil the details soon!

AMAR wrote:I've heard nothing but bad things about PES. A guy from the A8/S8 forum is fitting a Jaguar supercharger to his 4.3 V8 S8 though. Just waiting for him to unveil the details soon!

Hi Amar, thank you for post.

Read complete thread if you like

http://www.audizine.com/forum/showthrea ... deleted...

That's a really interesting thread. It's by no means black and white and I'm left thinking that PES aren't really the bad guys in this story.

the PES M90 sc is too small for this engine...it runs on the high end of the curve, low efficiency...
wait a bit for the APR kit, I've put the curves into an excel spreadsheet and the eff are much better:
PES M90 vs APR R1320
overall rpm range avg 52% vs 63%, 20%+ more efficient, meaning less heat and less parasitic loss
at 7000 42% vs 50%, 20%
at 5000 52% vs 67% almost 30% morre efficient!
at 3000 58% vs 70% 20%

I never mod, but this has got my interest

Blimey I think you need A level 'Math' to understand what all those percentages mean.

NIKKIrsSIXX wrote:Blimey I think you need A level 'Math' to understand what all those percentages mean.

what they mean, let's use the avg of 30% eff delta at 5000 rpm, 52% vs 67%
assume a sc makes a theroretical 140 HP worth of extra air/power
~5 psi of boost (5/14.7 x 414 ~ 140 HP)

at 52% eff 72 HP gets to the wheels
the rest, 68 HP, is lost due to heat of compression (maybe 20 HP) and power to drive the SC itself ~48HP...

for the 67%, 94 HP gets to the wheels
the balance, 46 HP, heat of compression (maybe 15 HP) and power to drive the SC ~30HP...

what this means?
94/72 ~ 30% or 22 more HP to the ground and 5 HP (3.7 KW) less heat the intercooler has to deal with...

these are 'round' numbers, but you get the idea...

I understand the maths. I know nothing about the specifics of superchargers, though, so I'll take your word for it, Arthur.

I was more interested by the flaming of PES that was going on, and the rather dignified response of PES. I thought they hold their own quite well.

Arthur: Do you know how much will APR kit cost? Isn't better save money and buy better car (GTR? )

BR

Garry

Did you mean better or faster?

Shoppinit wrote:Did you mean better or faster?

Only thing Im interested in is speed and Im afraid IMHO GTR is better. But I would like to know opinions of others. I heard that GTR is too perfect to enjoy driving.

Garry

cz.Garry wrote:Arthur: Do you know how much will APR kit cost? Isn't better save money and buy better car (GTR? )

BR
Garry

that's a question only you can answer
price, only APR can answer, lol

I myself am happy with the RS4, the overall package, the build quality, the usable nature of the power...plus it looks good...

+80-100HP and -100 lbs wouldn't hurt...

but honestly, the biggest issue imho is not power (rating, deposits, etc.), it's balance...60/40 plus 4000 lbs is pretty unwieldy...
2400/1600, 50% more on the front!
it's my only real criticism of the car, but the 40/60 awd set-up does a great job of mitigating it...
I'm sure this is accented coming from M3's, perfect balance, and my 944 Turbo, actually a bit more on the rear...

Im in love with my rs. Seats are great (having sporter one), steering wheel has some feed back, traction is perfect, sound of engine is good (i can imagine better).

BUT...
take a ride in civil remapped 335i and feeling of accelaration is much better (i know its not NA).

I do have 2 options:

1st - invest another $15k or $20k and take risk that it won't working (i know 350z twin turbo which after 1 year of servising still not working as promised by ...cant rememaber name of company (i think they are from australia but it doesnt matter)

2nd - try another car -> GTR personaly i dont like interior and exterior but the way which this car goes fast on road is incredible. Performance/price you won't find better rate.

Remapping ECUs or milltek full system or smt doens't make sense (+10 HP on 400 HP car isn't performace progres)

BR

Garry

that's a question only you can answer
price, only APR can answer, lol

I myself am happy with the RS4, the overall package, the build quality, the usable nature of the power...plus it looks good...

+80-100HP and -100 lbs wouldn't hurt...

but honestly, the biggest issue imho is not power (rating, deposits, etc.), it's balance...60/40 plus 4000 lbs is pretty unwieldy...
2400/1600, 50% more on the front!
it's my only real criticism of the car, but the 40/60 awd set-up does a great job of mitigating it...
I'm sure this is accented coming from M3's, perfect balance, and my 944 Turbo, actually a bit more on the rear...

Couple of alternative options to a supercharger? There is a twin turbo system that caldy was talking about where the turbos site next to the exhaust back boxes; can't remember what the company name is but once he's off the golf course I'm sure he'll tell you.

Also, for the money involved with a supercharger conversion, why not go after the primary principle and increase the power to weight ratio by adjusting the latter. CF, lighter wheel, lighter transmission / exhaust, interior etc etc. For that sort of money you could do a lot to improve th feel and performance of your car.

P_G wrote:Couple of alternative options to a supercharger? There is a twin turbo system that caldy was talking about where the turbos site next to the exhaust back boxes; can't remember what the company name is but once he's off the golf course I'm sure he'll tell you.

Also, for the money involved with a supercharger conversion, why not go after the primary principle and increase the power to weight ratio by adjusting the latter. CF, lighter wheel, lighter transmission / exhaust, interior etc etc. For that sort of money you could do a lot to improve th feel and performance of your car.

This will cost a lot of money and I'm afraid I won't go 0-200 -3.5s or smt. (how many kgs shall you save? 50, 60, 100? Still not enough!)

I don't understand how can audi 4seris weights 1723 kgs (mine)

Garry