upping(removing) the 155mph limiter

[Eatpies99]

Morning chaps.
Anyone know if the 174mph upgrade can be retrofitted to the rs4? I'd rather do that then have some company delimit it and lose my warranty.

Cheers

[Brooner]

Not heard of this
But to keep your warranty you would probably have to go through Audi and they will charge you a hefty premium for it if they will do it at all
Its £1300 on the configuration tool so be prepared to pay much more for Audi to do this

[Eatpies99]

Unfortunately that's what I thought. Gonna call in at some point and ask. No harm I guess.

[HYFR]

Why?

You'd need the worlds longest run way and a good headwind to reach 174mph

[Eatpies99]

hyfr, is the 174 another limiter? Or the cars actual top speed?? I just fancy going faster then 155. The car seems to hit that fairly easily.

[doodlebug]

I agree with HYFR, i'd not bother, won't get much passed 155, 174 is optimistic.

If you want speed then it was RS6 you're after.

[nwk00]

Official word is if your car is derestricted, it just means the speed restricter will kick in at 174mph instead of 155mph.

However, many owners have gone to 169mph on 155mph restricted car. Not sure why, but the restricter just doesn't kick in till then.

By that count, I guess on a 174mph restricted car, the top speed might be even higher, which is a good thing. But in reality, the car struggles past 165mph. Hence some owners think it's not necessary to spend the money to derestrict it because the car doesn't have the grunt for it.

If you are going to supercharge your car, I would say go for it otherwise spend the money elsewhere.

[PetrolDave]

I agree with HYFR, i'd not bother, won't get much passed 155, 174 is optimistic.

I'd be surprised if that were true - the B7 RS4 (with "only" 420PS) has been GPS measured by quite a few owners on German autobahns at 168mph or more - when fitted with the standard "155mph" limiter...

So surely the B8 with 30PS more and a slipperier shape should be able to beat that?

[RIV]

Why do you think Audi give you the option of lifting the limiter, if it's not going to go past 155????

[Graeme4130]

At Vmax last June, mine did repeated runs to an indicated 169, which gps registered at 163
Admittedly, the car was only 1200miles old, but it genuinely didn't have much left to give, and as Dave said, you'd need a blimmin long straight and a tailwind to hit 174
It did loosen up as the mikes went up, but still not by a massive amount and my car was making the full 450ps at the 246 RR Day
IMHO, the £1500 they want to up the limit is a massive rip off

[RIV]

IMHO, the £1500 they want to up the limit is a massive rip off

This!! Mines got the limiter lifted, but I didn't spec it, waste of money' as it will go over the stated 155 standard, as did my b7

[smudge]

At Vmax last June, mine did repeated runs to an indicated 169, which gps registered at 163
Admittedly, the car was only 1200miles old, but it genuinely didn't have much left to give, and as Dave said, you'd need a blimmin long straight and a tailwind to hit 174
It did loosen up as the mikes went up, but still not by a massive amount and my car was making the full 450ps at the 246 RR Day
IMHO, the £1500 they want to up the limit is a massive rip off

I would concur. My spec mentions nothing of removal of the 155 limit, but I have also managed at run of circa 165+ in mine under similar conditions to Graeme mentions (all be it I didn't have a GPS device running at the time), although my mileage was a higher than 1200. I don't see the point / need to remove it unless you own a strip of tarmac the length of the M275....?

[HYFR]

I agree with HYFR, i'd not bother, won't get much passed 155, 174 is optimistic.

I'd be surprised if that were true - the B7 RS4 (with "only" 420PS) has been GPS measured by quite a few owners on German autobahns at 168mph or more - when fitted with the standard "155mph" limiter...

So surely the B8 with 30PS more and a slipperier shape should be able to beat that?

More weight

My RS 5 had the factory derestriction and would struggle to hit 170

[Graeme4130]

My old b7 made 409bhp after carbon clean, and it struggled on to a gps measured 164, which the speedo though was nearer 175

[adsgreen]

I agree with HYFR, i'd not bother, won't get much passed 155, 174 is optimistic.

I'd be surprised if that were true - the B7 RS4 (with "only" 420PS) has been GPS measured by quite a few owners on German autobahns at 168mph or more - when fitted with the standard "155mph" limiter...

So surely the B8 with 30PS more and a slipperier shape should be able to beat that?

More weight

My RS 5 had the factory derestriction and would struggle to hit 170

Weight has a tiny tiny almost negligible effect on top speed.