Porsche Boxster 986 - engine swap project
Discussion
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.
I got Pirtek to make me the high pressure power steering line, re-using the original Porsche and Audi ends. That's the power steering finished and another job ticked off the list, not many things left to do now before i'm ready to drop the engine back out and start stripping it down.
I also test fitted the fuel rail, It's a stroke of luck how the fuel lines nicely curve around the oil cap, that's not something Audi designed as the manifold is facing the wrong way on my engine.
I also test fitted the fuel rail, It's a stroke of luck how the fuel lines nicely curve around the oil cap, that's not something Audi designed as the manifold is facing the wrong way on my engine.
I made up the fuel lines with the proper fittings.
The turbine housing on the Holset is a twin scroll design, I can't make use of that on my build so i've knife edged the divider and smoothed the edges of the flange. I also welded the internal wastegate shut and hacked off the actuator mounting tabs as the way it's clocked they were in the way of my oil feed,
The turbine housing on the Holset is a twin scroll design, I can't make use of that on my build so i've knife edged the divider and smoothed the edges of the flange. I also welded the internal wastegate shut and hacked off the actuator mounting tabs as the way it's clocked they were in the way of my oil feed,
I've finished the majority of the mocking up so i've pulled the engine back out ready to stripping it down
Cylinder heads removed
Here are the 2.7t (left) and 2.4 (right) cylinder heads, the 2.4's are like new compared to the 2.7's which is a result. The guy I bought the engine off (for peanuts) said it was low mileage and to be fair it does look it, no wear on the cams.
This pic shows how much larger the inlet ports are on the 2.4. The inlet cam also has a more aggressive profile than the 2.7. A good upgrade for a small outlay.
The 2.7 exhaust valves (left) have the collet slightly further down the stem than on the 2.4. I bought a set of spare valves from an Audi S4 so I didn't have to take the time to strip them out of my old heads. Glad I did as it's fiddly and i'm working on the floor, my knees are shot to bits now.
Fitting the valves and lapping them in.
Cylinder heads removed
Here are the 2.7t (left) and 2.4 (right) cylinder heads, the 2.4's are like new compared to the 2.7's which is a result. The guy I bought the engine off (for peanuts) said it was low mileage and to be fair it does look it, no wear on the cams.
This pic shows how much larger the inlet ports are on the 2.4. The inlet cam also has a more aggressive profile than the 2.7. A good upgrade for a small outlay.
The 2.7 exhaust valves (left) have the collet slightly further down the stem than on the 2.4. I bought a set of spare valves from an Audi S4 so I didn't have to take the time to strip them out of my old heads. Glad I did as it's fiddly and i'm working on the floor, my knees are shot to bits now.
Fitting the valves and lapping them in.
Standard conrods seem to be borderline at the power level i'm wanting so while the heads are off anyway I thought it best to put a set of forged ones in.
Dropped the sump and made a mess
Fitted the rods
I got a TTV Racing lightweight flywheel that's designed to take an Audi RS4 B7 clutch. I decided on a standard clutch as it'll be less harsh on the gearbox which I worry could be the weak link, also the Mrs can drive it easily. Hopefully it's up to the job, if not, i'll put a paddle clutch in it.
Fitted it.
Dropped the sump and made a mess
Fitted the rods
I got a TTV Racing lightweight flywheel that's designed to take an Audi RS4 B7 clutch. I decided on a standard clutch as it'll be less harsh on the gearbox which I worry could be the weak link, also the Mrs can drive it easily. Hopefully it's up to the job, if not, i'll put a paddle clutch in it.
Fitted it.
Cylinder heads are back on, along with a new water pump, thermostat and cambelt kit. When the old belt was removed, the tensioner had seized and there was loads of slack, got lucky with that. The bar is to lock the cams when doing the cambelt.
There is an auxiliary water pump that's designed to run when the engine is switched off. The purpose is to stop water boiling in the turbos and help cool them. I've decided i'm not going to run water lines on my turbo and I'm not using the fan controller that runs this pump so i've removed it.
Gave the cam covers a lick of textured paint.
The power steering pumps on the Audi and Porsche engines are pretty much the same so i've swapped over the smaller diameter pulley from the Boxster engine
There is an auxiliary water pump that's designed to run when the engine is switched off. The purpose is to stop water boiling in the turbos and help cool them. I've decided i'm not going to run water lines on my turbo and I'm not using the fan controller that runs this pump so i've removed it.
Gave the cam covers a lick of textured paint.
The power steering pumps on the Audi and Porsche engines are pretty much the same so i've swapped over the smaller diameter pulley from the Boxster engine
I knew it'd be needing a decent differential to help put the power down. Over the last few months i've had a stressful time trying to sort one out.
1st I stripped down my old diff. My hydraulic puller is my favourite toy.
The gearbox in my car is a 987 Boxster S 3.2, the 3.2 was made for a short period and there isn't much information about on it. A look on the Quaife website showed they listed the 986 S and 987 S (3.2 only) as the same part number. With that in mind, I started looking at the options for the 986 S. Ideally I wanted a plated diff. I saw on Facebook that EMC Motorsport had fitted a Kaaz LSD in a 986 S. Kaaz don't list it for that gearbox but it turned out it'll fit with some modification to the stub axles. I bought one.
The Kaaz didn't fit, it was completely different. EMC told me to bring them the box and they'd take a look. They did and it was totally different, Kaaz don't do one for my gearbox. Two days off work to take my box and collect it and a waste of both mine and EMC's time. It turns out Quaife have incorrectly listed the diffs on their website, not something i'd expect from a company like that. A call to my local Porsche parts dept. had them confirm the differential in my gearbox was the same part number as the one in a 3.4 Cayman S. There are LSD options for that.
A bit of googling found a company called Prestige Performance Centre GB that were doing a Wavetrac for £980, the next cheapest I had found was £1150. When I enquired about availability the return email was from Design 911 so the companies are linked. I ordered it and the next day I have a phone call from Design 911 telling me the price was wrong, it's £1300 so either I pay that or they'll cancel the order. Pretty poor form considering i'd enquired about it before hand and they didn't even bother to check the price. I personally think they should have honoured the price. I've bought something from them in the past that was in stock, it ended up coming from Germany, took about 3 weeks to arrive and they didn't let me know. s
t company, won't use them for anything in the future.
Then I found a company called Gripper, never heard of them before but I believe they are used in motorsport so thought i'd give them a go. They are a plated LSD like the Kaaz was and are set-up for my requirements. I ordered it from Corby Motorsport, told them I need an LSD for a Cayman S, it arrives and the box says "Cayman non S" on the label. A quick comparison, the height of the ring gear is wrong, the bolt holes are the wrong size and it'd need a huge shim on one of the bearings. They offered for me to send it back along with my original diff and they'll modify it. They seem nice enough but after my previous troubles i'm pissed off they've sent me a diff that's clearly going to be wrong. If they'd told me to send mine in 1st for comparison I would have. So that's getting sent back for a refund.
Someone reasonably local was selling a Cayman S gearbox that had a Quaife ATB fitted. The gearbox has 2nd gear synchro shot so it was a good price. I went and picked it up last night. At least I know for sure it'll fit my box and I won't waste any more time messing about with company's, the project is stalling over this. If I can fix the synchro i'll be able to keep the box as a spare (there is a reasonably high chance i'll be needing one at some point).
I'll be honest, a Quaife wasn't top of my list but it's better than an open diff, maintenance free unlike a plated diff and the car is mainly going to be used on the road so probably nicer to live with.
1st I stripped down my old diff. My hydraulic puller is my favourite toy.
The gearbox in my car is a 987 Boxster S 3.2, the 3.2 was made for a short period and there isn't much information about on it. A look on the Quaife website showed they listed the 986 S and 987 S (3.2 only) as the same part number. With that in mind, I started looking at the options for the 986 S. Ideally I wanted a plated diff. I saw on Facebook that EMC Motorsport had fitted a Kaaz LSD in a 986 S. Kaaz don't list it for that gearbox but it turned out it'll fit with some modification to the stub axles. I bought one.
The Kaaz didn't fit, it was completely different. EMC told me to bring them the box and they'd take a look. They did and it was totally different, Kaaz don't do one for my gearbox. Two days off work to take my box and collect it and a waste of both mine and EMC's time. It turns out Quaife have incorrectly listed the diffs on their website, not something i'd expect from a company like that. A call to my local Porsche parts dept. had them confirm the differential in my gearbox was the same part number as the one in a 3.4 Cayman S. There are LSD options for that.
A bit of googling found a company called Prestige Performance Centre GB that were doing a Wavetrac for £980, the next cheapest I had found was £1150. When I enquired about availability the return email was from Design 911 so the companies are linked. I ordered it and the next day I have a phone call from Design 911 telling me the price was wrong, it's £1300 so either I pay that or they'll cancel the order. Pretty poor form considering i'd enquired about it before hand and they didn't even bother to check the price. I personally think they should have honoured the price. I've bought something from them in the past that was in stock, it ended up coming from Germany, took about 3 weeks to arrive and they didn't let me know. s
t company, won't use them for anything in the future. Then I found a company called Gripper, never heard of them before but I believe they are used in motorsport so thought i'd give them a go. They are a plated LSD like the Kaaz was and are set-up for my requirements. I ordered it from Corby Motorsport, told them I need an LSD for a Cayman S, it arrives and the box says "Cayman non S" on the label. A quick comparison, the height of the ring gear is wrong, the bolt holes are the wrong size and it'd need a huge shim on one of the bearings. They offered for me to send it back along with my original diff and they'll modify it. They seem nice enough but after my previous troubles i'm pissed off they've sent me a diff that's clearly going to be wrong. If they'd told me to send mine in 1st for comparison I would have. So that's getting sent back for a refund.
Someone reasonably local was selling a Cayman S gearbox that had a Quaife ATB fitted. The gearbox has 2nd gear synchro shot so it was a good price. I went and picked it up last night. At least I know for sure it'll fit my box and I won't waste any more time messing about with company's, the project is stalling over this. If I can fix the synchro i'll be able to keep the box as a spare (there is a reasonably high chance i'll be needing one at some point).
I'll be honest, a Quaife wasn't top of my list but it's better than an open diff, maintenance free unlike a plated diff and the car is mainly going to be used on the road so probably nicer to live with.
Thanks, it'll probably be me that goes insane when it comes to the wiring.
I picked up some bits I had powder coated. I've got some modified suspension subframes (for driveshaft clearance) that aren't in these pictures, otherwise, these bits are all that i've needed to fabricate or modify to get the engine in the car. Just bolt on parts and nothing on the chassis modified. I didn't dare imagine it'd be this easy when I thought the idea up. The LS V8 converted ones in the USA require a fair amount of chassis hacking.
I picked up some bits I had powder coated. I've got some modified suspension subframes (for driveshaft clearance) that aren't in these pictures, otherwise, these bits are all that i've needed to fabricate or modify to get the engine in the car. Just bolt on parts and nothing on the chassis modified. I didn't dare imagine it'd be this easy when I thought the idea up. The LS V8 converted ones in the USA require a fair amount of chassis hacking.
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