Phoenix from the flames - Porsche Boxster with an Audi 2.7T
Discussion
Hopefully it won't be long before I can fire it up. I tried my best to find a way to get air to air intercoolers in but as it's a twin turbo the pipe work is a pain. I've made the decision to go for a water to air charge cooler like I did last time. This time, i'm taking a different approach, hopefully it'll perform ok, if not, I can always make changes at a later date. I bought a radiator, water pump and expansion tank from a Lexus CT200h, they are used to cool the inverter on the hybrid system. The plan is to fit the radiator under the engine rather than at the front of the car.
I finished up the exhaust this weekend. Happy with how it's turned out.
I made a start on the water to air charge cooler setup. The radiator is mounted under the engine, it's angled so it doesn't sit too low. I might add a shroud for it to help channel air through it. Expansion tank mounted in the engine bay this time. The water pump bolted straight into some existing holes from the air pump that was used for the old engine which was a nice surprise. I'm making a fair few compromises on this charge cooler setup compared to what I did last time around. I'll keep a close eye on the inlet air temperatures and make changes if required.
I made a start on the water to air charge cooler setup. The radiator is mounted under the engine, it's angled so it doesn't sit too low. I might add a shroud for it to help channel air through it. Expansion tank mounted in the engine bay this time. The water pump bolted straight into some existing holes from the air pump that was used for the old engine which was a nice surprise. I'm making a fair few compromises on this charge cooler setup compared to what I did last time around. I'll keep a close eye on the inlet air temperatures and make changes if required.
Coming together.
With regards to the cc setup. I imagine the booster setup is similar to the MR2 in that air is channelled up and through the engine cover vents?
You may be okay keeping everything in the rear but you'll have a smaller reservoir of coolant and may get heat soak when in stop start traffic. Hopefully nothing worse than keeping an eye on inlet temps and waiting for it to cool once on the move before giving it any WOT.
Good luck with the conversion, I love the practicalities of a either a bigger or more powerful engine as a way of getting more reliable horsepower.
With regards to the cc setup. I imagine the booster setup is similar to the MR2 in that air is channelled up and through the engine cover vents?
You may be okay keeping everything in the rear but you'll have a smaller reservoir of coolant and may get heat soak when in stop start traffic. Hopefully nothing worse than keeping an eye on inlet temps and waiting for it to cool once on the move before giving it any WOT.
Good luck with the conversion, I love the practicalities of a either a bigger or more powerful engine as a way of getting more reliable horsepower.
There are no vents above the engine compartment. There are just the vents on the side and they aren't very big. I wish there was an easy way improve things, most mid engine cars don't have a rear boot but the Boxster does.
The coolant heat soaking is one of the compromises I'm aware of, low capacity and the expansion tank is in a hot place, not ideal but I'll see how it performs before making changes.
The radiator under the car could be exposed to any debris I run over, I might add a shroud to protect it and help channel air.
The coolant heat soaking is one of the compromises I'm aware of, low capacity and the expansion tank is in a hot place, not ideal but I'll see how it performs before making changes.
The radiator under the car could be exposed to any debris I run over, I might add a shroud to protect it and help channel air.
I'm with James here, soft aluminium radiator being blasted by muck is not going to do it a world of favours - when I had my AC condenser replaced I made a grill of fine mesh that I glued onto the inside of the bumper, just to slow down the stones etc. I have pulled a large chunk of rubber (!) out of this, and it has taken a pummelling from stones, and this is on the very front of the car. The condenser is more pitted above this, so one can only imagine how bad the bottom would be now.
Maybe some form of wire mesh across the front to stop stones hitting it? - some type of fine expanded metal mesh, I bought mine from B&Q, holes are about 3mm by 5mm.
Maybe some form of wire mesh across the front to stop stones hitting it? - some type of fine expanded metal mesh, I bought mine from B&Q, holes are about 3mm by 5mm.
B'stard Child said:
Why ddn’t you use the AC rad as the chargecooler rad, it’s in a good place and surely the pipework runs are already there.
I attempted that on the last car but it didn't work out. One of the AC lines is really narrow so I think it would restrict flow too much, I tried to change the size of the pipes but I can't weld aluminium and so tried to use some brazing solder but it wasn't very strong. I'm going to get myself a tig welder in the future, being able to weld aluminium will make things easier. Also, there was no gas in the A/C system so that probably means i've got a rotten A/C rad (a contributing factor to me deciding to ditch the A/C). I may well end up switching to charge cooler radiators up front in the future if this setup isn't up to it but i've gone this way because the outlay was low (the radiator, pump and expansion tank cost £100) and it's not going to take me long to get it all installed and plumbed in.
Escy said:
There are no vents above the engine compartment. There are just the vents on the side and they aren't very big. I wish there was an easy way improve things, most mid engine cars don't have a rear boot but the Boxster does.
The coolant heat soaking is one of the compromises I'm aware of, low capacity and the expansion tank is in a hot place, not ideal but I'll see how it performs before making changes.
The radiator under the car could be exposed to any debris I run over, I might add a shroud to protect it and help channel air.
Just a thought (and you might laugh!) but could you buy a couple of PC fans and use them to try to cool or push air around the expansion tank?The coolant heat soaking is one of the compromises I'm aware of, low capacity and the expansion tank is in a hot place, not ideal but I'll see how it performs before making changes.
The radiator under the car could be exposed to any debris I run over, I might add a shroud to protect it and help channel air.
Might help perhaps? And they wont draw a huge amount of electricity either.
Just thought I'd throw the idea into the mix.
Escy said:
B'stard Child said:
Why ddn’t you use the AC rad as the chargecooler rad, it’s in a good place and surely the pipework runs are already there.
I attempted that on the last car but it didn't work out. One of the AC lines is really narrow so I think it would restrict flow too much, I tried to change the size of the pipes but I can't weld aluminium and so tried to use some brazing solder but it wasn't very strong. I'm going to get myself a tig welder in the future, being able to weld aluminium will make things easier. Also, there was no gas in the A/C system so that probably means i've got a rotten A/C rad (a contributing factor to me deciding to ditch the A/C). I may well end up switching to charge cooler radiators up front in the future if this setup isn't up to it but i've gone this way because the outlay was low (the radiator, pump and expansion tank cost £100) and it's not going to take me long to get it all installed and plumbed in.
Oi_Oi_Savaloy said:
Just a thought (and you might laugh!) but could you buy a couple of PC fans and use them to try to cool or push air around the expansion tank?
Might help perhaps? And they wont draw a huge amount of electricity either.
Just thought I'd throw the idea into the mix.
There is a fan that fits over the drivers side intake as standard. It's bulky so I've had to remove it for clearance. I'm going to fit a slimmer fan into it's housing.Might help perhaps? And they wont draw a huge amount of electricity either.
Just thought I'd throw the idea into the mix.
Venari said:
Escy: It's not clear from the thread... although you have moved the gearbox down (and thus the back of the engine at least) did you carve the Porsche's chassis to get clearance for the turbos? (like you trial-cut for research on the Mk 1 - R.I.P.)
Yes, I had to modify the body to clear the turbos. It wasn't very invasive, nothing like the trial cut on the old shell. I didn't cut anything out, just a slice, re-shaped the metal, trimmed the excess off and welded it up. One of the biggest hurdles I had left to sort out was an inlet pipe, the Audi has a Y pipe that goes from the MAF to the turbos, it sits on the top of the engine but I have no space for it. I decided to put it on the drivers side of the engine with one of the inlet pipes running across the front of the engine to the other turbo. It wouldn't fit in the space I had as it was so i've cut it up and used JB Weld epoxy to put it back together.
I needed to remove the standard engine compartment fan as it was too bulky. I've bought a slimmer fan which I wanted to fit inside the original housing. A little bit of trimming had it fitting nicely and I used some cable ties to hold it in place
I've pretty much finished all the engine pipe work now and have run all the charge cooler pipes also. I've just got one breather pipe left to connect up. There is hardly any free space in the engine bay, it's all been taken up by one thing or another. It's been a lot of effort working out where to put things, the more jobs I complete, the harder the remaining ones become.
I've made a start on the wiring, this is the last big thing left to do. There are a few things missing off the left hand drive wiring loom i'm using so I'm going to have to add them in. I find wiring really time consuming but if things go well this weekend I should be able to get it running.
I needed to remove the standard engine compartment fan as it was too bulky. I've bought a slimmer fan which I wanted to fit inside the original housing. A little bit of trimming had it fitting nicely and I used some cable ties to hold it in place
I've pretty much finished all the engine pipe work now and have run all the charge cooler pipes also. I've just got one breather pipe left to connect up. There is hardly any free space in the engine bay, it's all been taken up by one thing or another. It's been a lot of effort working out where to put things, the more jobs I complete, the harder the remaining ones become.
I've made a start on the wiring, this is the last big thing left to do. There are a few things missing off the left hand drive wiring loom i'm using so I'm going to have to add them in. I find wiring really time consuming but if things go well this weekend I should be able to get it running.
A picture of what's involved in removing the immobiliser from the Audi ECU. You need to short out a pin on one of the chips when you power it up so you can get it into boot mode, once it's in boot mode you can flash a different file on that doesn't have the immobiliser.
I had to move the pump for the air to water intercooler, I had it mounted up high next to the expansion tank, I knew it wasn't an ideal place but the fact it bolted straight up the Boxster was too tempting to ignore. I spent ages trying to get the system bled but had no joy, ended up having to move the pump lower down like I knew I should have done anyway. With that sorted i've spent most of the last few weeks doing wiring. I initially thought it was going to be easy as i'd done it before but there are a few differences on both the engine loom and the car from last time so I've had to go through it all again. Also, last time, I worked things out as I went but didn't make many notes and my memory failed me.
So the good news is, it's fired up!!!
https://youtu.be/i1tKTbom4x8
The whine in the video, is the power steering pump, it just needs the fluid topping up. I've got the engine management light on, have read the codes, it's all related to missing signals for the automatic transmission, it just needs to be re-coded. I've got another ECU that's from a manual (that's got the 300bhp re-map on it), that's still got the immobiliser on it so I need to go through the process above again. Either way, it's looking good, i'm not expecting any teething issues this time as it's all standard, it should just be a case of bleed all the fluids and it's ready to be driven. The exhaust seems pretty quiet also which i'm happy about.
I had to move the pump for the air to water intercooler, I had it mounted up high next to the expansion tank, I knew it wasn't an ideal place but the fact it bolted straight up the Boxster was too tempting to ignore. I spent ages trying to get the system bled but had no joy, ended up having to move the pump lower down like I knew I should have done anyway. With that sorted i've spent most of the last few weeks doing wiring. I initially thought it was going to be easy as i'd done it before but there are a few differences on both the engine loom and the car from last time so I've had to go through it all again. Also, last time, I worked things out as I went but didn't make many notes and my memory failed me.
So the good news is, it's fired up!!!
https://youtu.be/i1tKTbom4x8
The whine in the video, is the power steering pump, it just needs the fluid topping up. I've got the engine management light on, have read the codes, it's all related to missing signals for the automatic transmission, it just needs to be re-coded. I've got another ECU that's from a manual (that's got the 300bhp re-map on it), that's still got the immobiliser on it so I need to go through the process above again. Either way, it's looking good, i'm not expecting any teething issues this time as it's all standard, it should just be a case of bleed all the fluids and it's ready to be driven. The exhaust seems pretty quiet also which i'm happy about.
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