Porsche Boxster 986 - engine swap project
Discussion
I've gone with the 5 spokes, I like them, they are easier to keep clean and the majority of people seem to prefer them. I had to get some tyres, have decided to try out Federal 595 RS-R. I've gone 285/30's on the rear, they are the widest I could fit.
I'm running the inlet manifold the opposite way with it facing backwards as it makes running the charge pipes much shorter and easier to route. The problem is, the throttle body is angled upwards as standard to clear the power steering pump. This was giving me a clearance problem with the engine cover, it drops down quite sharply so the roof can fit in. With the power i'm wanting, it makes sense to fit a larger throttle body. I initially bought a V8 RS6 one but it was just too big to fit so I've picked up a B5 RS4 one (I try and avoid RS4 bits as the RS tax on everything is mental money). I've mounted it upside down and it's still a pretty tight fit.
I'm running the inlet manifold the opposite way with it facing backwards as it makes running the charge pipes much shorter and easier to route. The problem is, the throttle body is angled upwards as standard to clear the power steering pump. This was giving me a clearance problem with the engine cover, it drops down quite sharply so the roof can fit in. With the power i'm wanting, it makes sense to fit a larger throttle body. I initially bought a V8 RS6 one but it was just too big to fit so I've picked up a B5 RS4 one (I try and avoid RS4 bits as the RS tax on everything is mental money). I've mounted it upside down and it's still a pretty tight fit.
I can't wait to see it finished either 
I've not made any decisions on the post turbo exhaust yet, i've put it to the back of the list of things to be done. I might see how it sounds with no silencer at all, the turbo itself might be enough to keep it reasonable (although I doubt it).
I've not made any decisions on the post turbo exhaust yet, i've put it to the back of the list of things to be done. I might see how it sounds with no silencer at all, the turbo itself might be enough to keep it reasonable (although I doubt it).
Fantastic idea for a swap!
I had a B5 RS4 with 440 bhp and with all that low down torque when the turbos kicked in around 2.8k it was an absolute rocketship. I fitted a Bosch 044 pump and just needed injectors and another map in order to get 500+ bhp, but sold it at that point.
I hope those rear Federals can handle it when that huge single turbo kicks in!
I had a B5 RS4 with 440 bhp and with all that low down torque when the turbos kicked in around 2.8k it was an absolute rocketship. I fitted a Bosch 044 pump and just needed injectors and another map in order to get 500+ bhp, but sold it at that point.
I hope those rear Federals can handle it when that huge single turbo kicks in!
Ozzie Osmond said:
dom9 said:
How do you mean rear-engine?
Escy said:
Ozzie Osmond said:
dom9 said:
How do you mean rear-engine?
Escy said:
The engine should be in pretty much the same place.
So, flat-6 out, Audi V6 in!
JS1500 said:
Fantastic idea for a swap!
I had a B5 RS4 with 440 bhp and with all that low down torque when the turbos kicked in around 2.8k it was an absolute rocketship. I fitted a Bosch 044 pump and just needed injectors and another map in order to get 500+ bhp, but sold it at that point.
I hope those rear Federals can handle it when that huge single turbo kicks in!
I've got some Bosch 750cc injectors and an 044 pump to go on mine. I haven't been in a K04'd B5 but my mate has and he was suitably impressed so I can't wait to see how the engine performs in a Boxster. I also hope the tyres are up to it, I haven't tried them before but from reading the reviews the grip on offer is very good. That probably means they'll wear out in a couple of thousand miles. They are definately soft, they have picked up loads of grit just rolling them about on the garage floor. I had a B5 RS4 with 440 bhp and with all that low down torque when the turbos kicked in around 2.8k it was an absolute rocketship. I fitted a Bosch 044 pump and just needed injectors and another map in order to get 500+ bhp, but sold it at that point.
I hope those rear Federals can handle it when that huge single turbo kicks in!
dlockhart said:
I really hope that you get the cooling to work well
this is my new favorite thread
I think this is my biggest issue. Time will tell if I get it right 1st try but i've got a very big charge cooler and i'll try and get a decent size radiator up front. The pipes will run front to back and i'm looking at fitting a decent sized tank into the system so the water capacity should be quite large. The turbo being mounted behind the gearbox will help keep the engine bay temperatures down.this is my new favorite thread
dom9 said:
I see what you mean - it looks like pavement or road to the left in that picture but it's actually a shiny deck lid!
I was surprised by the shine on the boot, the car is covered in a layer of filth as can be seen in the other photos. Escy said:
I think this is my biggest issue. Time will tell if I get it right 1st try but i've got a very big charge cooler and i'll try and get a decent size radiator up front. The pipes will run front to back and i'm looking at fitting a decent sized tank into the system so the water capacity should be quite large. The turbo being mounted behind the gearbox will help keep the engine bay temperatures down.
Any pics of the Charge cooler you plan on using? key thing will be to get enough low temperature radiator. I know AMS did rear mounted rads on their twin turbo Audi R8 car. They have ducts and fans that pull air from under the car. Could be another option to try and get some more low temp radiator core volume as well as the front mounted rad.
Here it is. The boost pipes are 2.5" from the turbo into the core and 3" from there to the throttle body. It's a very short pipe run, especially compared to how the Audi S4 is. My charge cooler is quite big, I decided the best place to mount it was in the boot. I've had to cut a hole in the boot floor above the turbo for the boost pipe to come through and i'm using the original hole where the engine wiring loom came through for the other boost pipe. The 1st picture shows how it is as standard (the holes are from a tracker that was fitted), the second shows where i've opened up the small hole to join the larger one so the wiring loom can fit. The wiring loom is longer on the Audi engine so i've had to coil it up inside the boot, the hole section that's coiled up was originally a straight bit that was encased in a rubber that was poured over it as a liquid in a mould. This was a total nightmare to strip back, between myself and my brother who helped, there was probably about 10 hours that went into just doing that. The 3rd photo is the charge cooler fitted and the Audi ECU bolted in. It's a minor miracle that the 3" boost pipe from the charge cooler to the throttle body fits, especially with the wiring loom running next to it. There is hardly any space there, to get it in and out the engine needs to be lowered off it's mount. The one hole in the boot floor and the opening up of the hole where the original wiring loom was are literally the only cutting of the bodyshell i've had to do and both are minor. I'm pretty proud of that considering the scale of the modifications i'm doing.
The 997 wheels required spacers to get the fitment right (rears were hitting the coilovers and the fronts are set too far inside the arch). Spacers and wheel bolts tend to be a pain in the arse when fitting the wheels and I expect the wheels will probably be coming off quite regularly so I've gone for a stud and nut conversion
The 997 wheels required spacers to get the fitment right (rears were hitting the coilovers and the fronts are set too far inside the arch). Spacers and wheel bolts tend to be a pain in the arse when fitting the wheels and I expect the wheels will probably be coming off quite regularly so I've gone for a stud and nut conversion
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