Need opinions on a S5 project

[Low Flyer]

Hey guys, I am new to the S5 boards as I have a B5 S4 and a B8 S4. My idea is to purchase a higher mileage v8 manual and swap a motor in it....my choices are a VR6-T, LSX and boost later, a 2.7t or even an older RS6 4.2 and still retain quattro. Any ideas suggestions or thoughts would be greatly appreciated!

[mozman68]

Hey guys, I am new to the S5 boards as I have a B5 S4 and a B8 S4. My idea is to purchase a higher mileage v8 manual and swap a motor in it....my choices are a VR6-T, LSX and boost later, a 2.7t or even an older RS6 4.2 and still retain quattro. Any ideas suggestions or thoughts would be greatly appreciated!

We're all a bunch of poseurs that buy our way into kewlness and wouldn't know the first thing about swapping engines.

Why not just rebuild the standard V8 and then supercharge it? I don't think you could do better than that and would be easier than a full swap considering all the crap you would have to match up.

[ParadigmTony]

Hey guys, I am new to the S5 boards as I have a B5 S4 and a B8 S4. My idea is to purchase a higher mileage v8 manual and swap a motor in it....my choices are a VR6-T, LSX and boost later, a 2.7t or even an older RS6 4.2 and still retain quattro. Any ideas suggestions or thoughts would be greatly appreciated!

Welcome to the party. You're not gonna find many techs around here.. But i do love everyone. Do it! But honestly if you're gonna swap it, you could just as easily and maybe even more affordably by an A5, as you're more than likely going to be sourcing a new trans anyway. The big standoff here is factory ECU control, on any trim its a fairly intricate ECU making rewiring impossible so you'd need to go stand alone. The downfall here being any of the Audi motors you mention will require absurd rewiring hours. Once accomplished you still have the hurdle of getting the stock ecu to think the motor is still in the car so its operational with countless other features. (Im trying to broad stroke and avoid talking too much)

Once the electronics are handled, drivetrain is the next consideration. A RWD conversion won't be that difficult, and something I've been looking into. The Electronic power steering will likely need to be addressed via coding. Rear end and final drive gearing will also be a consideration. Fueling on the more modern engines will be tough but will likely work better with the existing pumps and supply but will also need to be wired in.

In short dollars for dollars and LSX would likely be the cheapest, but expect to lose a lot of the "Audi" experience. Finding a good electronics guy is going to be priority 1. Transmission and driveline priority two.

[Low Flyer]

Thank you for the input so far, I figured on running PRO-efi or AEM for standalone. The S5 body has grown on me and I just want a different fun toy out of it. I Still have my B8 S4 for the refined ride. As you guys have stated the electronics will be tricky, but I want something a little, well unique. I found adapters for the LS motors and the VR6 to mount to the manual O1E.

[ParadigmTony]

Thank you for the input so far, I figured on running PRO-efi or AEM for standalone. The S5 body has grown on me and I just want a different fun toy out of it. I Still have my B8 S4 for the refined ride. As you guys have stated the electronics will be tricky, but I want something a little, well unique. I found adapters for the LS motors and the VR6 to mount to the manual O1E.

Are you just going to convert to RWD and eliminate the front diff? Im assuming yes, because I dont know what you'd do for front shafts on the LS, custom oil pan perhaps. I dont know much about the LS honestly so I have no idea where the sump etc is. The AEM infinity is the way to go in terms of Engine management. The VE tuning is far superior to pulse width monotony. Driveline is perhaps what interests me most.

[NaiveTurtle]

Unless you are going stand alone ECU for say an LSX, putting an Audi motor in the S5 will be a royal pain. Take the 2.7TT for example (since this was one of the motors I was contemplating swapping into my S5), the electronics will be the relatively straight forward part as you would use the harness and ECU from an early generation B5 S4 or C5 Allroad. Some connections will have to be modified, but it is all relatively doable. For reference go take a look at the 2.7TT swap guide in the B6 A4 section.

The rather difficult part is mounting the 2.7TT into the B8 subframe. This is not just a simple drop in and bolt up job, you will have to have custom engine mounts made since nothing off the shelf will likely work. The 2.7TT has mounts similar/identical to the B6/B7 which has the motor sitting on top of the motor mount which is supported by the sub frame. The B8 motor mount holds the motor horizontally where you bolt the motor mount to the sub frame and then to the motor horizontally (parallel to the ground). From there you will have to make sure the engine is in the right position which make require modifying the subframe to bring the motor forward/backwards or up/down.

I had an idea a while back to use a 3.0TDI motor out of a Q7 and drop it into the S5 as it will bolt right up to the B8 subframe and motor mounts. The issue here is the cost to do such a swap. It would be awesome to have a 400hp/700ft-lb diesel monster to roll coal on people but the cost to do the swap is the same if not a lot more than just supercharging the V8 already in the S5. After finding a TDI motor and ECU you would have to re-plumb all the fuel lines and replace the fuel pump, on top of the performance parts to make that kind of power/torque.

[ParadigmTony]

Unless you are going stand alone ECU for say an LSX, putting an Audi motor in the S5 will be a royal pain. Take the 2.7TT for example (since this was one of the motors I was contemplating swapping into my S5), the electronics will be the relatively straight forward part as you would use the harness and ECU from an early generation B5 S4 or C5 Allroad. Some connections will have to be modified, but it is all relatively doable. For reference go take a look at the 2.7TT swap guide in the B6 A4 section.

The rather difficult part is mounting the 2.7TT into the B8 subframe. This is not just a simple drop in and bolt up job, you will have to have custom engine mounts made since nothing off the shelf will likely work. The 2.7TT has mounts similar/identical to the B6/B7 which has the motor sitting on top of the motor mount which is supported by the sub frame. The B8 motor mount holds the motor horizontally where you bolt the motor mount to the sub frame and then to the motor horizontally (parallel to the ground). From there you will have to make sure the engine is in the right position which make require modifying the subframe to bring the motor forward/backwards or up/down.

I had an idea a while back to use a 3.0TDI motor out of a Q7 and drop it into the S5 as it will bolt right up to the B8 subframe and motor mounts. The issue here is the cost to do such a swap. It would be awesome to have a 400hp/700ft-lb diesel monster to roll coal on people but the cost to do the swap is the same if not a lot more than just supercharging the V8 already in the S5. After finding a TDI motor and ECU you would have to re-plumb all the fuel lines and replace the fuel pump, on top of the performance parts to make that kind of power/torque.

I just took the liberty of assuming he had the capability of fabricating motor mounts. The big problem is any motor that it is close to mounting is 3x as much as a more powerful crate lsx etc. For the differential in cost you can easily have the fab work done. As for ecu, the med9 is not going to do you any favors. At best retaining it to run comfort features and stand alone to run the motor. The problem being communication to the med9 and then of course obd2 for inspection etc. Wiring and ecu is the impasse, but can be if you work around it, not through it. Everything else can be fabricated. An LSX with AEM infinity 8, walbro fuel pumps, and new lines is basically all you need to fire. Trans and driveline can be custom fab'd. The stock rear is capable of holding some solid power. The biggest job is pulling the trigger and tearing the heart out a beautiful living creature.

[JoshDub]

If you're doing something like a VR6-t, wouldnt you be much better starting off with a 3.2 A5? Not to mention it'll be cheaper.

[jwr9152]

Ever think about the 2.5 5 cylinder? They are getting 600 HP and over 500 ft-lbs out of them and would take a lot of weight off the front end. And if you could get it to make the same noises the old trans am car did it would just be fantastic.

[Low Flyer]

I really appreciate all the input guys! I notice that rear wheel drive has been brought up. I eas assuming that the O1E in the manual cars were the same as like the b5 and could retain all wheel drive wit drives haft shop axles. I never really thought about the 5cyl...that does sound like an idea. I am actively looking for an S5 as of now, because of it having better brakes and being a little bit more beefier than an S5, is that assumption correct?

[doug97gxe]

some insight http://www.audizine.com/forum/showth...a-Quattro-home

[JoshDub]

I really appreciate all the input guys! I notice that rear wheel drive has been brought up. I eas assuming that the O1E in the manual cars were the same as like the b5 and could retain all wheel drive wit drives haft shop axles. I never really thought about the 5cyl...that does sound like an idea. I am actively looking for an S5 as of now, because of it having better brakes and being a little bit more beefier than an S5, is that assumption correct?

You're going to want to upgrade the brakes anyway. The a5 and S5 share the same body. Just get a sline 3.2 a5 since you already want to do a vr6 or 2.8 swap.