Porsche Boxster 986 - engine swap project
Discussion
Thought i'd start a build thread for my Boxster. I bought a 986 Boxster S with an engine swap in mind in Autumn last year. I like engine swaps, I enjoy the building of them and love the results. I've built a few MR2 Roadsters with 2ZZ engine swaps and they are great and have turned me onto the mid engine platform. I initially was looking into doing a VX220 with a Saab B204 engine swap but by the time i'd sold my AE86 (also engine swapped) i'd missed the boat a bit and the prices on the VX220 have started going up.
I turned my attention towards the Porsche Boxster. It's common for MR2's, Elise's and VX220's to be modified/engine swapped but it's strangely rare for the Boxster. I learned that the Boxster shares a common bell housing pattern with Audi which got me thinking. I had looked at Audi V8's, there are a couple knocking around in the USA but not much info on them. My friend has an Audi S4 B5 with the 2.7 bi-turbo which i'm impressed with. A donor car can be had cheap and they are manual from the factory unlike the V8's which would make things a bit easier. Also, the power potential on the V6 is fantastic and I felt if it's worth doing the project i'd want more power than the Audi V8 offers.
My plan at the start of the project was for about 400bhp running on some K04 turbos. As I started buying parts i'm now thinking more like 550bhp give or take.
I decided to go for the Boxster S as the base for the project over a 2.5 or 2.7 as it has an extra radiator in the front, better brakes, 6 speed gearbox, larger wheel bearings and i'd just rather have an S anyway. I picked up a nice example with the BBS GT3 split rims, hardtop and clear lights. The most important thing was it wasn't silver as they all seem to be and that's boring. I ran the car as it was for a month or so and I have to say I am impressed, they handle well and I could actually have lived with the standard 250bhp, it seemed plenty quick enough. I did actually re-consider my plans as I liked it more than I thought I would. My reasoning behind the swap in the 1st place is that Porsche engines are very unreliable and they seem to be ticking time bombs, various issues, IMS bearings, cracked cylinder heads, cracked liners, bore score, etc. I'd never have total confidence in the engine not letting me down in an expensive way, it seems a total lottery. The Audi engine on the other hand can be bought for 1/4 of the value and they are over engineered, plenty of 400+bhp S4's running around with 200k on them that have never been re-built.
These were taken on my way home from buying it.
I bought my donor car on ebay, bought it before I actually had the Porsche. It didn't matter if I had an A6 or S4 as the donor so I just waited for something suitable in manual to come along. Lot's seem to be high mileage badly maintained dogs so I avoided those. I like to take a punt and this was a total gamble, it had been sat for 3 years after the owner had passed away. The advert said it'll start on jump leads but that was pretty much it. The miles were pretty reasonable at 106k (the Boxster is on 93k). I won the auction and paid a bloke to collect it for me, I didn't even go and look at it. I'd spotted it had a lovely set of Recaro seats in it so it was worth a roll of the dice. Even though it was covered in filth and full of cobwebs I could tell it's a good car. It's only had one owner since 2001. The engine runs great and is whisper quiet and that's the only thing that I really cared about. The interior being in fantastic condition was a nice bonus as were Pirelli's all round with lots of tread. A signs it had been looked after. It also came with a free old man hat.
It didn't take long for things to start slipping on my 400bhp plan, I was initially going to just go for larger turbos on a standard engine. After reading up about the 2.7 bi-turbo I found that a nice upgrade is to fit cylinder heads from a naturally aspirated Audi V6, they have more aggressive inlet camshafts and much larger ports. I found a low mileage 2.4 V6 for pocket money so thought why not? So I bought it. This will change the characteristics of the engine which should suit the Porsche. The 2.7 is known as a bit of a torque monster, great on a 4x4 saloon that's heavy, not ideal for a lighter rwd sports car where the transaxle might be the weak link so it'll trade torque for more peak power.
I didn't strip many parts off the Audi as I couldn't be bothered so off it went for scrap
Part of my reasoning for this engine swap was that it would bolt to the transaxle but I knew if I used a Boxster S as my base, that wasn't actually the case. I picked up a spare 986 S transaxle (as I hadn't removed the Boxster engine but wanted to start planning things) and placed the Audi V6 spacer plate on it. Only half the holes lined up and the starter motor is in the wrong position. There is also no place to mount the crank sensor either. These issues could be worked around but I wanted a bolt on solution. A 5spd 986 trans is actually an Audi unit and bolts straight to the Audi V6 and has the right sensor locations, this was the easy option but they are weaker and replacing a 6spd with a 5spd felt a downgrade. I decided to buy a 987 S 3.2 transaxle, this has the starter in the right place and all the holes are the same. I had to drill and tap a couple of holes and open out the casting for the flywheel sensor. Fitting that gearbox into a 986 hasn't been done before so there are a few hurdles i've discovered, the driveshafts are unequal lengths unlike the originals so i've had to make up a hybrid set using the 986 ends on the 987 shafts, that was easier said than done as they outer CV's aren't designed to be serviced.
I put a fresh MOT on the Boxster before I pulled the engine to make testing and mapping easier at the other end.
I bolted the trans to the engine and offered it up inside the engine bay. It's a surprisingly good fit. I will need to reverse the inlet manifold, like in the picture and the trans will need to sit half an inch lower and an inch further forward. The distance between the 987 trans diff output flanges and the bellhousing are shorter than on the 986 trans, that's a good thing as it will improve on the driveshaft angles which plagues the standard 986 S but as i've had to move the trans an inch forward it's making the driveshafts foul the suspension arm carriers. So these will be getting modified for clearance. So far so good, the engine and box fit with only minor modifications to bolt on parts. I'll also need to modify the throttle body angle to have enough clearance for the engine cover. I'm currently in the process of making my engine subframe.
The standard location for the turbos is no good as it will foul the boot, i've decided it makes more sense to go for a large single (which I think i'll mount on the back of the transaxle). I bought a hybrid Holset, which is a combination of the HX35 and HX40. Should be capable of 650+bhp. Here is a picture of it next to a standard KO3 turbo.
This is pretty much where the project is, i'll be updating as I go, hopefully things will move along at a reasonable pace, i'm aiming to have it done before the summer.
I turned my attention towards the Porsche Boxster. It's common for MR2's, Elise's and VX220's to be modified/engine swapped but it's strangely rare for the Boxster. I learned that the Boxster shares a common bell housing pattern with Audi which got me thinking. I had looked at Audi V8's, there are a couple knocking around in the USA but not much info on them. My friend has an Audi S4 B5 with the 2.7 bi-turbo which i'm impressed with. A donor car can be had cheap and they are manual from the factory unlike the V8's which would make things a bit easier. Also, the power potential on the V6 is fantastic and I felt if it's worth doing the project i'd want more power than the Audi V8 offers.
My plan at the start of the project was for about 400bhp running on some K04 turbos. As I started buying parts i'm now thinking more like 550bhp give or take.
I decided to go for the Boxster S as the base for the project over a 2.5 or 2.7 as it has an extra radiator in the front, better brakes, 6 speed gearbox, larger wheel bearings and i'd just rather have an S anyway. I picked up a nice example with the BBS GT3 split rims, hardtop and clear lights. The most important thing was it wasn't silver as they all seem to be and that's boring. I ran the car as it was for a month or so and I have to say I am impressed, they handle well and I could actually have lived with the standard 250bhp, it seemed plenty quick enough. I did actually re-consider my plans as I liked it more than I thought I would. My reasoning behind the swap in the 1st place is that Porsche engines are very unreliable and they seem to be ticking time bombs, various issues, IMS bearings, cracked cylinder heads, cracked liners, bore score, etc. I'd never have total confidence in the engine not letting me down in an expensive way, it seems a total lottery. The Audi engine on the other hand can be bought for 1/4 of the value and they are over engineered, plenty of 400+bhp S4's running around with 200k on them that have never been re-built.
These were taken on my way home from buying it.
I bought my donor car on ebay, bought it before I actually had the Porsche. It didn't matter if I had an A6 or S4 as the donor so I just waited for something suitable in manual to come along. Lot's seem to be high mileage badly maintained dogs so I avoided those. I like to take a punt and this was a total gamble, it had been sat for 3 years after the owner had passed away. The advert said it'll start on jump leads but that was pretty much it. The miles were pretty reasonable at 106k (the Boxster is on 93k). I won the auction and paid a bloke to collect it for me, I didn't even go and look at it. I'd spotted it had a lovely set of Recaro seats in it so it was worth a roll of the dice. Even though it was covered in filth and full of cobwebs I could tell it's a good car. It's only had one owner since 2001. The engine runs great and is whisper quiet and that's the only thing that I really cared about. The interior being in fantastic condition was a nice bonus as were Pirelli's all round with lots of tread. A signs it had been looked after. It also came with a free old man hat.
It didn't take long for things to start slipping on my 400bhp plan, I was initially going to just go for larger turbos on a standard engine. After reading up about the 2.7 bi-turbo I found that a nice upgrade is to fit cylinder heads from a naturally aspirated Audi V6, they have more aggressive inlet camshafts and much larger ports. I found a low mileage 2.4 V6 for pocket money so thought why not? So I bought it. This will change the characteristics of the engine which should suit the Porsche. The 2.7 is known as a bit of a torque monster, great on a 4x4 saloon that's heavy, not ideal for a lighter rwd sports car where the transaxle might be the weak link so it'll trade torque for more peak power.
I didn't strip many parts off the Audi as I couldn't be bothered so off it went for scrap
Part of my reasoning for this engine swap was that it would bolt to the transaxle but I knew if I used a Boxster S as my base, that wasn't actually the case. I picked up a spare 986 S transaxle (as I hadn't removed the Boxster engine but wanted to start planning things) and placed the Audi V6 spacer plate on it. Only half the holes lined up and the starter motor is in the wrong position. There is also no place to mount the crank sensor either. These issues could be worked around but I wanted a bolt on solution. A 5spd 986 trans is actually an Audi unit and bolts straight to the Audi V6 and has the right sensor locations, this was the easy option but they are weaker and replacing a 6spd with a 5spd felt a downgrade. I decided to buy a 987 S 3.2 transaxle, this has the starter in the right place and all the holes are the same. I had to drill and tap a couple of holes and open out the casting for the flywheel sensor. Fitting that gearbox into a 986 hasn't been done before so there are a few hurdles i've discovered, the driveshafts are unequal lengths unlike the originals so i've had to make up a hybrid set using the 986 ends on the 987 shafts, that was easier said than done as they outer CV's aren't designed to be serviced.
I put a fresh MOT on the Boxster before I pulled the engine to make testing and mapping easier at the other end.
I bolted the trans to the engine and offered it up inside the engine bay. It's a surprisingly good fit. I will need to reverse the inlet manifold, like in the picture and the trans will need to sit half an inch lower and an inch further forward. The distance between the 987 trans diff output flanges and the bellhousing are shorter than on the 986 trans, that's a good thing as it will improve on the driveshaft angles which plagues the standard 986 S but as i've had to move the trans an inch forward it's making the driveshafts foul the suspension arm carriers. So these will be getting modified for clearance. So far so good, the engine and box fit with only minor modifications to bolt on parts. I'll also need to modify the throttle body angle to have enough clearance for the engine cover. I'm currently in the process of making my engine subframe.
The standard location for the turbos is no good as it will foul the boot, i've decided it makes more sense to go for a large single (which I think i'll mount on the back of the transaxle). I bought a hybrid Holset, which is a combination of the HX35 and HX40. Should be capable of 650+bhp. Here is a picture of it next to a standard KO3 turbo.
This is pretty much where the project is, i'll be updating as I go, hopefully things will move along at a reasonable pace, i'm aiming to have it done before the summer.
Thanks for the positive comments.
The engine mounts will be finished this weekend, then I can concentrate on mounting the turbo and making the exhaust. Once the exhaust is sorted, that's the major fabrication out of the way and the progress should speed up.
pidsy said:
have you got a timescale in mind OP?
I'd like it done by late spring so I can use it in the summer. It seems realistic to me but projects like this can sometimes eat up time.The engine mounts will be finished this weekend, then I can concentrate on mounting the turbo and making the exhaust. Once the exhaust is sorted, that's the major fabrication out of the way and the progress should speed up.
I'm aware of the TPC Racing turbo kit, and the Subaru engine conversions done by another company in the US, i'm going to take some ideas from their set-up.
I'm going to use a charge cooler.
I was planning on leaving the suspension standard and seeing how it handled and also how the project was looking budget wise but i've had my hand forced. The driveshafts are fouling the suspension upright that holds the rear arms, i've modified them for clearance but when the rear wheels are off the ground the suspension drops and the shafts sit on the suspension upright where the rear wishbone is, it's only slight contact but it would be a problem come MOT time. I've bought some coilovers, which should provide the extra clearance needed. I'm also going to run wider 997 wheels and they will hopefully improve the clearance so I don't need large spacers. I'll update the thread showing what I mean when they arrive.
I've not made any decisions on the fuel system yet other than running Bosch 750cc injectors which I bought a while back. I've been reading that the big power 996 Turbo guys add a Bosch 044 inline pump to supplement the standard pump so I may go a similar route.
I'm going to use a charge cooler.
I was planning on leaving the suspension standard and seeing how it handled and also how the project was looking budget wise but i've had my hand forced. The driveshafts are fouling the suspension upright that holds the rear arms, i've modified them for clearance but when the rear wheels are off the ground the suspension drops and the shafts sit on the suspension upright where the rear wishbone is, it's only slight contact but it would be a problem come MOT time. I've bought some coilovers, which should provide the extra clearance needed. I'm also going to run wider 997 wheels and they will hopefully improve the clearance so I don't need large spacers. I'll update the thread showing what I mean when they arrive.
I've not made any decisions on the fuel system yet other than running Bosch 750cc injectors which I bought a while back. I've been reading that the big power 996 Turbo guys add a Bosch 044 inline pump to supplement the standard pump so I may go a similar route.
Edited by Escy on Thursday 4th February 14:21
J4CKO said:
Watching with interest.
What kind of power will it have when its finished ?
I mentioned 550bhp in the 1st post as a rough target. What kind of power will it have when its finished ?
cb1965 said:
Excellent project, I always wondered why more people didn't tinker with the Boxster as they are cheap enough secondhand now and I suspect are capable of handling more power better than most. I had a 3.2S and to be honest it always felt a bit underwhelming, like it was able to do more but was constrained by the economy of its powertrain.
Good luck and I shall be reading this with interest.
I get the feeling it'll still feel composed with double the power. I hope so anyway!Good luck and I shall be reading this with interest.
Edited by Escy on Thursday 4th February 19:37
LankyLegoHead said:
This is a mammoth task, but awesome all the same!
I do enjoy the irony of calling the Porsche engine unreliable, and then getting what is a B5 S4 engine. I have a lot of friends who have 1, or 2 or even the RS4 of similar vintage. They are extremely expensive to run and nearly all over 100k require new turbos/rebuilt!
However, what with this being a complete build NONE of that should be a problem for you!
The engine itself is as bulletproof as they come but some of the bits bolted to it aren't (turbo's and EGT sensors seem to be common failures) but like you say, they won't be an issue for my build. I do enjoy the irony of calling the Porsche engine unreliable, and then getting what is a B5 S4 engine. I have a lot of friends who have 1, or 2 or even the RS4 of similar vintage. They are extremely expensive to run and nearly all over 100k require new turbos/rebuilt!
However, what with this being a complete build NONE of that should be a problem for you!
I guess that means this is a good idea.
Little update.
This weekend I finished up the engine mounts, the engine is now bolted into the chassis. I'm using the standard Boxster engine mount locations, i've cut and re-welded the gearbox mounts (as the gearbox has moved forward an inch) and made a cradle that bolts to the original V6 engine mount brackets and it ties into the front of the engine where the original snub mount was bolted. The standard Boxster mount then bolts to this cradle. The picture shows it mounted to my 2.4 block that I bought for the cylinder heads, it came in handy for mocking this up.
I was having some problems with driveshaft clearance, with the wheels off the ground the driveshafts were resting on the lower suspension arm mount. I knew coilovers would solve this as they have a shorter body so the hub wouldn't drop as much. I hadn't originally planned on coilovers, it was something i'd look at once it was up running so I was mindful about blowing the budget and leaving myself short in other areas. There aren't many options around for Boxsters that's reasonable money. You got the cheap and nasty £350 ones on ebay otherwise it's over £1000 for a set. After trawling the internet I came across some made by Yellow Speed Racing, i'm also into my Jap cars and knew their coilovers have a good reputation. They have adjustable top mounts and adjustable damping which will help me get it set-up nicely since i'm messing with the weight distribution. They seemed like very good value for £700 so that's what I went with.
I fitted a rear shock this evening to have a quick look, i've now got loads more space under the driveshaft which has solved the clearance issue and also given me tons more space for running the exhaust which is going to be very useful.
Little update.
This weekend I finished up the engine mounts, the engine is now bolted into the chassis. I'm using the standard Boxster engine mount locations, i've cut and re-welded the gearbox mounts (as the gearbox has moved forward an inch) and made a cradle that bolts to the original V6 engine mount brackets and it ties into the front of the engine where the original snub mount was bolted. The standard Boxster mount then bolts to this cradle. The picture shows it mounted to my 2.4 block that I bought for the cylinder heads, it came in handy for mocking this up.
I was having some problems with driveshaft clearance, with the wheels off the ground the driveshafts were resting on the lower suspension arm mount. I knew coilovers would solve this as they have a shorter body so the hub wouldn't drop as much. I hadn't originally planned on coilovers, it was something i'd look at once it was up running so I was mindful about blowing the budget and leaving myself short in other areas. There aren't many options around for Boxsters that's reasonable money. You got the cheap and nasty £350 ones on ebay otherwise it's over £1000 for a set. After trawling the internet I came across some made by Yellow Speed Racing, i'm also into my Jap cars and knew their coilovers have a good reputation. They have adjustable top mounts and adjustable damping which will help me get it set-up nicely since i'm messing with the weight distribution. They seemed like very good value for £700 so that's what I went with.
I fitted a rear shock this evening to have a quick look, i've now got loads more space under the driveshaft which has solved the clearance issue and also given me tons more space for running the exhaust which is going to be very useful.
This weekend I started the exhaust. I also made a bracket to mount the turbo off the back of the transaxle. My original plan was to have the car looking completely standard but it's not going to be easy to keep the center exit exhaust if I want to run a silencer, which I do. To be honest, I think the center exit on a Boxster looks crap anyway, i'm considering cutting the center of bumper away like has been done on this MX5. I'd then have a silencer from the back of the turbo with the pipe exiting at the driver's side of the bumper Opinions on this idea are welcome.
Thanks for the replies.
VerySideways said:
I think the stock appearance has appeal, and I'm not super keen on the rear bumper cut away...
Could you keep the centre exit pipes as dummies and hide the real pipe exit somewhere else, like with a diesel turn down pipe hidden behind the bumper (without setting the bumper on fire!))?
I hadn't actually thought of that. Fake exhausts are generally tragic but would be acceptable in this case. This seems like the best solution, think I might go this way. Could you keep the centre exit pipes as dummies and hide the real pipe exit somewhere else, like with a diesel turn down pipe hidden behind the bumper (without setting the bumper on fire!))?
chuntington101 said:
What's the reason for going single turbo over twins? I think it would be cool if you could see the turbos slightly beneath the bumper like some of the big turbo air cooled 911s.
I was in two minds which way to go regarding single turbo vs twins. In the US, everyone chasing big power goes single turbo on S4's as they perform better. Also, going single keeps the pipe work easier to fabricate. I test fitted the rear bumper and the compressor housing can still be seen poking out underneath.RB Will said:
Ace project. And being done with what looks like a Halfords tool kit, gives me hope for achieving something with mine lol
Thanks, my Halfords tool kit has had a hard life I made some good progress this weekend. I bought a load of exhaust parts and got started on the exhaust. I modified the exhaust manifolds with 90 degree bends (forgot to take pictures) and then made the downpipes. It was a bit of a challenge to fit two 2.25" pipes down one side of the car as space is limited, it took me a while working everything out. I'm happy with how it's turned out, especially considering all the cuts were made with 4.5" angle grinder so it was murder trying to get the angles right and the cuts straight so I had tight fits. I still need to add lambda bosses and the external wastegate pipe, then i'll heatwrap it. I think this section of the exhaust will prove to be the hardest fabrication of the whole build so I feel like it's all downhill now
Edited by Escy on Sunday 6th March 14:35
I picked up some 18" 997 Carrera alloys as they were really cheap. They are slightly wider 8" vs 7.5" at the front and 10" vs 9" at the rear but will require spacers to fit the rears so I might not be able to get much extra tyre width on them. I think the weight is about the same. Not sure which I prefer so i'm interested in opinions
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).
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. 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
The power steering pump on Boxster has the reservoir built in so i've had to add one. A mate was scrapping a Discovery so I took the reservoir off that. You can see how much space I have down the sides of the engine, makes working on it nice and easy compared to the flat 6.
Because the turbo is mounted low i'm going to use an oil scavenge pump. Made up a bracket and welded it onto a trans mount.
I was advised that the pre-turbo exhaust i'd made being 3" diameter was a mistake, slower spool up with no benefit anywhere else. I decided to re-do that section in 2.5". I also added in the external wastegate, using a Turbosmart Hypergate 45.
The turbo has a 4" diameter compressor inlet so I made up a 4" AFM housing and got a K&N filter for it. It's not clear in the pictures but it sits the other side of the chassis leg, behind the rear arch liner which happens to have some vents in it. I'll probably add a heat shield at a later date.
Because the turbo is mounted low i'm going to use an oil scavenge pump. Made up a bracket and welded it onto a trans mount.
I was advised that the pre-turbo exhaust i'd made being 3" diameter was a mistake, slower spool up with no benefit anywhere else. I decided to re-do that section in 2.5". I also added in the external wastegate, using a Turbosmart Hypergate 45.
The turbo has a 4" diameter compressor inlet so I made up a 4" AFM housing and got a K&N filter for it. It's not clear in the pictures but it sits the other side of the chassis leg, behind the rear arch liner which happens to have some vents in it. I'll probably add a heat shield at a later date.
Thanks, I'm pleased with how it's coming together. The turbo is a hybrid Holset. This was the spec in the advert.
Large alloy HX35 compressor housing, with 4inch anti-surge MWE ported inlet (VERY loud turbo spool!) and 2.5inch outlet.
HX40 60mm inducer (biggest of the HX40 compressor inducers) 8blade compressor wheel 650bhp+ and 40psi boost.
Rare and brand new water and oil cooled journal bearing core, with 4x water ports, 360deg thrust bearing, and heavy duty shaft.
New 70mm (GT3582R is 68mm) 12 blade high flow turbine wheel giving minimal pre-turbine backpressure for maximum performance.
12cm (Around A/R 0.85 in a turbo of this frame size) twin scroll turbine housing with divided T3 inlet flange and 2.5in V-band outlet.
Turbo suitable for 1.6ltr (ideally using twin scroll manifold) to 5ltr petrol engines (+ larger diesels) looking for 400-600bhp.
Large alloy HX35 compressor housing, with 4inch anti-surge MWE ported inlet (VERY loud turbo spool!) and 2.5inch outlet.
HX40 60mm inducer (biggest of the HX40 compressor inducers) 8blade compressor wheel 650bhp+ and 40psi boost.
Rare and brand new water and oil cooled journal bearing core, with 4x water ports, 360deg thrust bearing, and heavy duty shaft.
New 70mm (GT3582R is 68mm) 12 blade high flow turbine wheel giving minimal pre-turbine backpressure for maximum performance.
12cm (Around A/R 0.85 in a turbo of this frame size) twin scroll turbine housing with divided T3 inlet flange and 2.5in V-band outlet.
Turbo suitable for 1.6ltr (ideally using twin scroll manifold) to 5ltr petrol engines (+ larger diesels) looking for 400-600bhp.
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