Knackered old Porsche with loads of natural light - Boxster!
Discussion
poppopbangbang said:
IAT's on the road are just about acceptable, at a bar they're high 40's/low 50's, at 1.4bar mid 50's. Pretty amazing given the charge cooler core is only 150mm long! It's pretty clear that I need to improve this for higher boost levels but package space is pretty tight, I only have about 400mm total length to fit something into but I'm not that limited on width so could do something short and wide.
Not sure if it makes much difference with the configuration you currently have, but interested to know how much higher the IATs were compared to ambient on the day.
Congrats on the successful dyno! Given the turbo and engine spec it's rude to leave it at 340hp 
What are your thoughts for the exhaust? Might a valved bypass system work so as to keep idle/low rev noise reasonable and then a bit straight-pipey above about 4k-5k rpm?
Something that always surprises me at track days is how forced induction cars have virtually no engine noise coming out the exhaust - just the hair dryer noise and that seems to be even for cars with minimal silencing.
What are your thoughts for the exhaust? Might a valved bypass system work so as to keep idle/low rev noise reasonable and then a bit straight-pipey above about 4k-5k rpm?
Something that always surprises me at track days is how forced induction cars have virtually no engine noise coming out the exhaust - just the hair dryer noise and that seems to be even for cars with minimal silencing.
braddo said:
Congrats on the successful dyno! Given the turbo and engine spec it's rude to leave it at 340hp
I agree, I'm going to turn it up to 400 beans as that was the original plan with 500 to follow from there. braddo said:
What are your thoughts for the exhaust? Might a valved bypass system work so as to keep idle/low rev noise reasonable and then a bit straight-pipey above about 4k-5k rpm?
Something that always surprises me at track days is how forced induction cars have virtually no engine noise coming out the exhaust - just the hair dryer noise and that seems to be even for cars with minimal silencing.
Generally turbo cars are quite as the turbo should be pulling a whole load of energy out of the exhaut flow to drive it. I'm considering doing a straight pipe with just a Cat in it but with room for a silencer to be fitted at a later date. This way on the dyno we can measure the Cat flow capacity etc. and make sure we don't have a significant restriction there. Something that always surprises me at track days is how forced induction cars have virtually no engine noise coming out the exhaust - just the hair dryer noise and that seems to be even for cars with minimal silencing.
I really wanted to keep the standard Boxster silencer as it's very obvious under the rear bumper so with that missing it gives the game away that it's somewhat modified, however needs must.
I've also ordered a P13 chargecooler so we'll see where that gets us. Those two things and back to the dyno to see if we can make 400 on standard cams without needing too much boost/torque to do it within the limits of the cams, I could easily make 400bhp at 6000RPM but with the torque to do that I'm over the top of the gearbox limit then by quite some margin.
It is lovely to be into development on this already as it's essentially bypassed the usual problem solving and making it work properly stage which is a lot less fun!
poppopbangbang said:
I really wanted to keep the standard Boxster silencer as it's very obvious under the rear bumper so with that missing it gives the game away that it's somewhat modified, however needs must.
Yeah, that's why I was wondering about a valved system or even just a straight pipe going through the middle of the box (and out through the existing exit or a downpipe through the bottom of the 'silencer').
braddo said:
Yeah, that's why I was wondering about a valved system or even just a straight pipe going through the middle of the box (and out through the existing exit or a downpipe through the bottom of the 'silencer').
I could chop the box back in half and just keep the lower section for looks..... that might work rather well thinking about it 
It's a Creality Ferret so very similar in spec to yours I think? The trick I have found is to use markers on any large parts and it scans flawlessly (albeit within the resolution limits present in the hardware), never looses track even when making sharp turns around stuff. Without markers everything is much, much more difficult.
Escy said:
I was making 400ft/lb on a 5 speed. I haven't got a power and torque figure on my current setup but based on previous dyno time and 100-200 times I'm high 500's at the moment. The 2.7t makes similar torque to bhp typically so I'd say around 550ft/lb.
What clutch were you on with this Escy? I know you've got something fairly fancy now but was that on an RS4 one? I was running a TTV flywheel which took a B7 RS4 clutch. I think the main difference in fitment is the size of the dowels, it's the same size as the B5 RS4 but has a higher torque rating.
I had OEM spec LUK Repset, think it was about £150 from Euro Car Parts (so probably not as good as a genuine Audi clutch?).
That held up fine, even at my current power level until the day I changed gear (flat foot shift) at slightly lower RPM and landed right in the phattest part of the torque curve. It had put up with a lot up until that point.
It was a very nice pedal on that clutch, better than most standard Boxsters I've driven. My current one it a bit stiffer but I only notice it in traffic.
I had OEM spec LUK Repset, think it was about £150 from Euro Car Parts (so probably not as good as a genuine Audi clutch?).
That held up fine, even at my current power level until the day I changed gear (flat foot shift) at slightly lower RPM and landed right in the phattest part of the torque curve. It had put up with a lot up until that point.
It was a very nice pedal on that clutch, better than most standard Boxsters I've driven. My current one it a bit stiffer but I only notice it in traffic.
Nothing says "tightly packaged" like a blister
These will keep the 3D printer busy for a while and once done I'll bond them into place with some 330 as that's good for 100 degrees and has a little bit of gap fill and flex to it. I'll gold foil the lower section of the cover and that should box off the engine cover
These will keep the 3D printer busy for a while and once done I'll bond them into place with some 330 as that's good for 100 degrees and has a little bit of gap fill and flex to it. I'll gold foil the lower section of the cover and that should box off the engine cover
Spare box has arrived from Spain:
Looks to be in great condition and clearly has lived in the dry for it's life to date. Plan is to get this off for a strip and checkover along with ATB fit and then swap it into the car in due course once we've finished all the dyno work etc.
I'll use the flanges from the current gearbox and will either source some really good used (rare) or new selector parts as the ones on my gearbox are in a bit of a manky state!
Looks to be in great condition and clearly has lived in the dry for it's life to date. Plan is to get this off for a strip and checkover along with ATB fit and then swap it into the car in due course once we've finished all the dyno work etc.
I'll use the flanges from the current gearbox and will either source some really good used (rare) or new selector parts as the ones on my gearbox are in a bit of a manky state!
Mclaren charge cooler is here:
A little battered as it's off a crashed one but I'll be modifying the brackets anyway and the core holds pressure..... plus it was a very reasonable price as a result!
P13 is 570S.
Core looks very nice!
On the 570S these support about 325bhp a side on tuned cars without too much issue, however that is also via sharing coolant with the engine. Whilst it's a seperate low temperature circuit that goes through the CC rad first it's still going to be considerably hotter than a seperate system would be - the US tuner guys seem keen on seperating the circuits for greater performance. I'm hoping giving it a greater delta between coolant and charge will help these do a little more.
There is also a convenient TMAP boss on the exit tank which will be perfect for a WI injector
I'm going to get this on ASAP and see what it does to charge tempeatures with exhaust to follow at some point in the not too distant future.
A little battered as it's off a crashed one but I'll be modifying the brackets anyway and the core holds pressure..... plus it was a very reasonable price as a result!
P13 is 570S.
Core looks very nice!
On the 570S these support about 325bhp a side on tuned cars without too much issue, however that is also via sharing coolant with the engine. Whilst it's a seperate low temperature circuit that goes through the CC rad first it's still going to be considerably hotter than a seperate system would be - the US tuner guys seem keen on seperating the circuits for greater performance. I'm hoping giving it a greater delta between coolant and charge will help these do a little more.
There is also a convenient TMAP boss on the exit tank which will be perfect for a WI injector
I'm going to get this on ASAP and see what it does to charge tempeatures with exhaust to follow at some point in the not too distant future.
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