s6 engine vs a6 4.2. what is the difference?

**golonaus** · 05-25-2007 10:03 AM

s6 is making 340hp 40 over regular 4.2
what is the difference??
I guess exhaust making no more than 10 extra hp's.

**Kievskiy** · 05-25-2007 11:05 AM

tunning.....

**Alpinevelo** · 05-25-2007 12:06 PM

Also some 4.2 engines have 32 valves and the S6 has a 40 valve 4.2L engine. Some of the newer 4.2 A6s have the same amount of valves but are software governed to make them fuel efficient.
So that's where you see some people adding performance fuel injectors to some cars looking to get additional horse power. I know a buddy who owns a project S4 V8 and added Bosch fuel injectors, but I am not sure about the results...
Something to ponder for sure...

**TheBlueMartin** · 05-25-2007 12:34 PM

Im sorry to say this, but this place is always good for a laugh.
The true answer is:

Intake manifold (standard is a 2 vane, S6 is a 3)
Camshafts (all 4; 2 intake, 2exhaust).
ECU

They both have the same stroke, bore, and valve configuration.
Otherwise the engines are the same, and yes, the parts in interchangable.
IIRC, wholesale cost on the cams are $1100 each (x4), and in intake is around $2000. Total install time is around 18 hours.

Its not worth it for 40hp.

**Alpinevelo** · 05-25-2007 01:55 PM

Originally Posted by TheBlueMartin

Im sorry to say this, but this place is always good for a laugh.
The true answer is:

Intake manifold (standard is a 2 vane, S6 is a 3)
Camshafts (all 4; 2 intake, 2exhaust).
ECU

They both have the same stroke, bore, and valve configuration.
Otherwise the engines are the same, and yes, the parts in interchangable.
IIRC, wholesale cost on the cams are $1100 each (x4), and in intake is around $2000. Total install time is around 18 hours.

Its not worth it for 40hp.

Kiev, at least we had the ECU part correct LOL. Blue I am glad you didn't jump to the Lexus side, we need someone has to keep us honest here...

Damn Wikipedia...sucks!!!

**Kievskiy** · 05-25-2007 02:37 PM

i actually came back to say it can be intake, hahaha, Blue you got the correct answer, cool you kept a6:)

**TheBlueMartin** · 05-25-2007 02:38 PM

The only reason I know about this is I looked into doing a swap 3 years ago. Its not worth the money IMO, because the extra 40hp only comes in over 4000rpm, which I rarely use that range anyways. The stock 4.2 has a little more power down low, but I cant find the graph.

Ill still be going to the Lexus side someday, I just cant justify 4 years of payments to get rid of a car I love...

yet

**Kievskiy** · 05-25-2007 02:47 PM

at least get an gs or ls hybrid:)

**TheBlueMartin** · 05-25-2007 03:35 PM

Originally Posted by kievskiy

at least get an gs or ls hybrid:)

Piss on that. Ill have my hands on a 600h next month, but none of the Lexus hybrids are worth the money.

I want a 01-04 GS430, and then let the modding begin!

**Alpinevelo** · 05-25-2007 03:40 PM

So realistically, was my buddy with the S4 wasting his money adding a "performance fuel injection system?" I think it was a CNC machined pump and the actual injectors...

**Kievskiy** · 05-25-2007 04:30 PM

so u planning to do JDM VIP style huh?

toyota aristo ftw

Originally Posted by TheBlueMartin

Piss on that. Ill have my hands on a 600h next month, but none of the Lexus hybrids are worth the money.

I want a 01-04 GS430, and then let the modding begin!

**TheBlueMartin** · 05-25-2007 06:19 PM

Originally Posted by Alpinevelo

So realistically, was my buddy with the S4 wasting his money adding a "performance fuel injection system?" I think it was a CNC machined pump and the actual injectors...

Is it a 4.2 S4? If so, its a very different motor than a C5 4.2

Originally Posted by kievskiy

so u planning to do JDM VIP style huh?

toyota aristo ftw

hell yeah, thats what Im talkin about. JDM badging would be just the start. TRD everything....

**2Quick** · 05-28-2007 11:55 AM

So, whats the major difference between the S6 4.2 and the S4 4.2? Is the difference major or minor tweaks? Just wondering...

**TheBlueMartin** · 05-28-2007 08:26 PM

Originally Posted by 2Quick

So, whats the major difference between the S6 4.2 and the S4 4.2? Is the difference major or minor tweaks? Just wondering...

Very different motors. The B6/7 S4 has the new timing chain style motor, while you have the older timing belt style motor. There are more differences than I can list...

**Bobcat77** · 08-27-2018 09:52 AM

Originally Posted by TheBlueMartin

Im sorry to say this, but this place is always good for a laugh.
The true answer is:

Intake manifold (standard is a 2 vane, S6 is a 3)
Camshafts (all 4; 2 intake, 2exhaust).
ECU

They both have the same stroke, bore, and valve configuration.
Otherwise the engines are the same, and yes, the parts in interchangable.
IIRC, wholesale cost on the cams are $1100 each (x4), and in intake is around $2000. Total install time is around 18 hours.

Its not worth it for 40hp.

Hi
I have a 2001 S6 bought it 2 months ago. Everything was fine till 2 days agothere was a sound in the engine, showed it to a mechanic and he said the engine is gone!!!! So he suggested buying a new engine. It's not easy to find an S6 engine so He said maybe the lower engine of the regular A6 4.2 is the same as the S6 !! Is that true? So if i buy a half A6 4.2 will fit my S6 ??
Thanks