Allroad 4.2 vs S4 4.2 and a question for JHM

[Capt. Obvious]

Sorry if this has already been covered ad nauseum, but the search function is not so functional at the moment.

I've been looking at some 4.2 allroads and I'm curious if the engine in those and the S4 are the same engine, with the allroad just being de-tuned 40hp?

If they are different, what are the differences?

And more important, do any of the JHM goodies for the S4 fit on the allroad 4.2 (headers, software, etc.)?

Thanks.

[beemercer]

Not sure on the headers, but the upcoming intake manifold and nitrous setups will. A modded intake manifold, catless (or at least pre-cat gutted piggies) downpipes, well designed 2.5" X-pipe catback, and tune (JHM should be able to do one for the A6) should net you around 380 CHP.

The headers and twin turbo setup may be iffy. I'd guess the Allroad would have more space seeing as its a larger chassis, but the manifolds for the turbo setup and headers are so tightly fit they may rub on other items in the engine bay. Not saying it won't happen, but you may need to relocate certain items.

[Capt. Obvious]

I'm not too worried about the forced induction stuff, I'd want to keep it N/A and just make it as mean as possible that way. I just want to know if their software will work with the allroad and if I would see the same gains vs. with the S4.

[Kookie]

Totally not trying to be a smart ass. But what does JHM have to say about it?

[beemercer]

I'm not too worried about the forced induction stuff, I'd want to keep it N/A and just make it as mean as possible that way. I just want to know if their software will work with the allroad and if I would see the same gains vs. with the S4.

Give 'em a call 209-968-0077, it's best if you call right around 9am PST.

[JohnnyAlQaeda]

Sorry if this has already been covered ad nauseum, but the search function is not so functional at the moment.

I've been looking at some 4.2 allroads and I'm curious if the engine in those and the S4 are the same engine, with the allroad just being de-tuned 40hp?

If they are different, what are the differences?

And more important, do any of the JHM goodies for the S4 fit on the allroad 4.2 (headers, software, etc.)?
Thanks.

i think TylerS has an article on the differences between the motors. main thing is size as they had to redesign it to fit in the S4 engine bay. other than that i recall seeing that its tuned different to have a lower torque band.

[djwimbo]

I was curious about this as well, but since I'm not in the market to buy, I figured I wouldn't ask.

4.2 AllRoads are fuckin sexy.

[Bpitz15]

Not sure on the headers, but the upcoming intake manifold and nitrous setups will. A modded intake manifold, catless (or at least pre-cat gutted piggies) downpipes, well designed 2.5" X-pipe catback, and tune (JHM should be able to do one for the A6) should net you around 380 CHP.

The headers and twin turbo setup may be iffy. I'd guess the Allroad would have more space seeing as its a larger chassis, but the manifolds for the turbo setup and headers are so tightly fit they may rub on other items in the engine bay. Not saying it won't happen, but you may need to relocate certain items.

are you sure about that? Through a "miscommunication" with a member on here, I purchased an Allroad/A6 4.2 Intake manifold from a member on here though the ad said S4 4.2, and the part numbers/fuel rail setups are different. I guess i'll let JHM chime in, but im pretty sure the intake mani will not work.

***Shameless Plug I do still have that intake for sale. =) ***

[SoCalS4Avant]

I was curious about this as well, but since I'm not in the market to buy, I figured I wouldn't ask.

4.2 AllRoads are fuckin sexy.

Agreed - sexy as all hell.

As for the engine. My understanding is that they are quite different. You can see Bpitz's experience above...something about different versions of the 4.2. Much like the old 4.2 from the A6, A8, S6, and S8. IIRC, the Allroad 4.2 is the same as those.

[tylerS]

i think TylerS has an article on the differences between the motors. main thing is size as they had to redesign it to fit in the S4 engine bay. other than that i recall seeing that its tuned different to have a lower torque band.

i can't take credit for this, it was speedetc who posted the s4 portion of the study guide in justin's teardown thread.

[Capt. Obvious]

Interesting. VERY interesting. I wonder if here are any other important differences between the BHF and BAS besides tuning?

[justinperkins]

It's a belt-driven engine vs. ours is chain driven. That's a pretty huge difference.

edit: this is a false statement ^

[tylerS]

It's a belt-driven engine vs. ours is chain driven. That's a pretty huge difference.

i'm not sure if that is correct

[Capt. Obvious]

Wrong. The 4.2 in the allroad is not based off of the belt-driven 4.2 in the C5 A6 4.2 or S6. It is chain driven, like the 4.2 in the S4. What I'm trying to determine is if the engines are the same with different tuning, or if there are any other differences between the two (different internals, cams, etc.).

[tylerS]

Wrong. The 4.2 in the allroad is not based off of the belt-driven 4.2 in A6 4.2 or C5 S6. It is chain driven, like the 4.2 in the S4. What I'm trying to determine is if the engines are the same with different tuning, or if there are any other differences between the two (different internals, cams, etc.).

i'll go through the bentley manual when i get home and see if i can find anything

[Capt. Obvious]

i'll go through the bentley manual when i get home and see if i can find anything

You sir, are a gentleman and scholar.

[JohnnyAlQaeda]

yeah Tylers a damn good guy EXTREMELY helpful

[beemercer]

are you sure about that? Through a "miscommunication" with a member on here, I purchased an Allroad/A6 4.2 Intake manifold from a member on here though the ad said S4 4.2, and the part numbers/fuel rail setups are different. I guess i'll let JHM chime in, but im pretty sure the intake mani will not work.

***Shameless Plug I do still have that intake for sale. =) ***

Was it an Allroad or an A6 intake manifold? I thought the A6's were belt driven and the Allroad were chain motors. Could be different considering the Allroad is tuned for lower end power.

[Bpitz15]

not entirely sure, i have the PN sitting on my desk back at the office. ill check it out tomorrow

[justinperkins]

Wrong. The 4.2 in the allroad is not based off of the belt-driven 4.2 in the C5 A6 4.2 or S6. .

Well shiver me timbers, I've always thought that 4.2 in the allroad was the same as the A6 4.2.

The more you know.

[jfunkey]

ok the allroad 4.2 04+ is the same motor *short block* So crank pulley will work. * Long block *. Different cams, different throttle body *little unsure*

The intake should be the same. The tune obviously will be different but JHM I don't see why they couldn't work the majic on that to make an even bigger difference then the S4.

[Papachristou]

one of the guys here just dyno'ed 24 awhp gain with straight piggies and catback FYI

[tylerS]

so my license is only good for bhf and bns for 4.2s. i think what jfunkey said is right. i found this and it looks like it has the same 2stage manifold. it's probably just detuned

[beemercer]

one of the guys here just dyno'ed 24 awhp gain with straight piggies and catback FYI

And 50 ft/lbs of torque to the wheels. And that is without a tune, on 91 octane, and at 6000ft of elevation.

[Capt. Obvious]

And 50 ft/lbs of torque to the wheels. And that is without a tune, on 91 octane, and at 6000ft of elevation.

Holy crap.

I wonder how the allroad tiptronic would like 400ish horsepower/ft lbs of torque?

[Capt. Obvious]

Oh, and where the hell is JHM in this thread? I want to know if their software will work with an allroad!

[beemercer]

Holy crap.

I wonder how the allroad tiptronic would like 400ish horsepower/ft lbs of torque?

If it's the same transmission as the S4's it won't be a problem. Are they a 5 or 6 speed?

[beemercer]

Oh, and where the hell is JHM in this thread? I want to know if their software will work with an allroad!

Best bet is to call, they are very busy recently.

[Capt. Obvious]

Best bet is to call, they are very busy recently.

I guess I'll have to do that. I was hoping they'd answer in here for future reference if someone were (*gasp*) using the search function. I'll just report back my findings.

[beemercer]

I guess I'll have to do that. I was hoping they'd answer in here for future reference if someone were (*gasp*) using the search function. I'll just report back my findings.

Good point, no one uses search though don't be silly

[Capt. Obvious]

so my license is only good for bhf and bns for 4.2s. i think what jfunkey said is right. i found this and it looks like it has the same 2stage manifold. it's probably just detuned

I haven't been able to find out anything else, what about you Tyler?

[jfunkey]

I haven't been able to find out anything else, what about you Tyler?

Your answer is here. [email protected]

And yah no one uses the search function anymore so maybe you can post the answer here for those that just might

[Capt. Obvious]

Sent JHM an email. I'll post their reply in here.

[c4racer]

Holy crap.

I wonder how the allroad tiptronic would like 400ish horsepower/ft lbs of torque?

oh sure. The only question is for how long?

[Bpitz15]

are you sure about that? Through a "miscommunication" with a member on here, I purchased an Allroad/A6 4.2 Intake manifold from a member on here though the ad said S4 4.2, and the part numbers/fuel rail setups are different. I guess i'll let JHM chime in, but im pretty sure the intake mani will not work.

***Shameless Plug I do still have that intake for sale. =) ***

Can someone grab the information on this part number?
PN 077 133 185 AM

[quattrojedi]

was there ever a response from the email? Am I totally missing a huge thread of 4.2 Allroad goodness??