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Orphan 01-02-2008 11:52 PM

Info on the 4.2L FSI
Hey guys,

Just after lots of info on the 4.2L FSI V8, everything from technical build info to dimensions of the full engine, weight etc as well as any performance knowledge about the engine.

Being FSI it should be able to run 12psi boost easy through an intercooler with the 11:1 compression right? Have a guy near my place that is running 17psi through a 10:1 toyota v8 from the early 90's so I'd hope the audi engine would be able to stand up to it. What is the stock bottom end like? How much power are they known to hold and how much abuse can these engines take?

Also interested in some info on the 4.2L TDI V8. Is it the same as the FSI just diesel with glow plugs rather than spark plugs? Are the blocks the same etc?

Would love tech drawings etc of the engines as well if anyone has some.

I have googled and haven't been able to come up with a whole lot so thought i'd check out an audi community.

Thanks for your time guys.

EDIT: also are there any 6 speed manual transmission that will bolt up to the 4.2L FSI? I mean FR transmissions not the quattro ones. Is there a way to turn a quattro transmission into just a straight FR?

Orphan 01-05-2008 01:39 AM

What a boring forum, feel free to delete my account I won't be coming back.

Badger61 01-05-2008 05:56 AM

Ok goodbye then

Orphan 01-05-2008 08:22 AM

lol i'm not being a **** head but what is the point of a forum if no one even replies or has anything useful to say.

Badger61 01-05-2008 08:36 AM

As this is a public forum I doubt very much if anybody has any in depth technical information on this relatively new engine and is not turbocharged in any of the current range.

If it helps the 4.2 diesel is a completely different engine that is turbocharged.

There is no current front wheel drive transmission that can handle the output of the 4.2 FSi and I don't know of anyone who convert a Quattro to run as such.

Good luck in your search.

Orphan 01-06-2008 12:49 AM

Thanks for your reply.

As for the transmission I meant rear wheel drive. FR as in a front engine rear drive car.

Hah was just wondering if the blocks and head ports for the TDI and FSI were the same as then it might be possible to bolt the turbos on from the TDI onto an FSI for a pretty easy power upgrade.

Is the FSI that different to the last model 4.2L V8? I thought it was just some minor refinements in the head + the injection and the block etc would be pretty much the same but beefed up for the RS4 etc versions.

Badger61 01-06-2008 07:08 AM

The main difference between the earlier V8 and the FSi is the use of chain drive for the cams at the rear of the engine enclosed by a casing between the engine and gearbox where as the earlier engine uses conventional belt driven cams at the front.Good old Audi

Orphan 01-07-2008 03:11 AM

I so don't get the thinking behind putting it at the rear of the engine. I mean sure since its a chain its not like you have to replace it every so often but what if you do need to... be a freaken fiddly job. Its not like they couldn't have just swapped the belt for a chain on the front of the engine haha.

Any ideas why they did that? Still love the sound either way :P Now they just need to get some sorta variable valve timing and lift going, seems to only be two stage systems unless you go into the big bucks of pnenumic (spelling?) valves, those ones like in formula 1.

Badger61 01-07-2008 01:12 PM

Main reason being that it is maintainence free, yes it is a real pain to strip as I found out on a V6 FSi. Another reason is that the engine can actually be shorter in the block, this helps with positioning of the engine in the car as legislation for pedestrian safety now requires a distance in the front crumble zone between front of car and engine. The new Audi Valve Lift System introduced on the later V6 is still two stage that uses two different cam profiles switching over via engine ECU controlled solenoids.

Orphan 01-08-2008 03:23 AM

The 4.2L FSI is 520mm long isn't it? Thats pretty short, any idea how tall the engine is?

How did you do it? do you have to unbolt it from the sub frame and crane it forward a bit or something?

Ok so its like vtec and nissans Neo VVL? two sets of lobes, oil lines controlled by soilenoids to engage the other lobe etc. Any idea when the VVL will be introduced on the V8? Far out that would be nice. With good springs it could probably rev up to 9-10k with ease. I know a lot of the SR20VET guys (a nissan engine with VVL) just put better springs in and they can safely rev up to 9-10k with weaker internals.

Any idea how much a front cut with ecu etc of a 4.2L FSI would be or are they hard to get?

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