Couple of GT4 owner questions if you can help - Page 1 - Boxster/Cayman - PistonHeads UK

Hi, Just had my first run out in the car. The PSE sports exhaust - I cannot hear any difference when on or off, at any rev range, and with the window open or close - normal? I can hear the value/or something move when pressing on the button on the drive. Buckets - does the middle sections pull out - are they velcro'd? Dip in power around 5K normal? Thanks!

There should be a noticeable difference both at idle and when the valves open at 4000 revs with PSE. Yes the seat centres are Velcro’d in and come out, recently did this to install a bolster protector…. Definitely no power dip at 5000 revs, that’s weird, need a return trip to OPC I’m afraid!

johnycarrera said: There should be a noticeable difference both at idle and when the valves open at 4000 revs with PSE. Yes the seat centres are Velcro’d in and come out, recently did this to install a bolster protector…. Definitely no power dip at 5000 revs, that’s weird, need a return trip to OPC I’m afraid! Not a good start then! Thanks

There is a power dip at around 5k on the stock car when you look at the dyno charts… Some people can perceive it… other not so much. Here is a comparison of stock 981 GT4 (red) to stock 718 GT4 (blue) Can easily be tuned out with just an off the shelf map or other options if you have an appetite for light modifications. As for your PSE valves… you’ll just need to make sure they are operating correctly on both sides… as it might be that only one is working. With the car off.. turn the key in the ignition just to power on but not start the car. Open window or door. Press the PSE button and you should hear the valves open. If you’re not sure you can have a look under the car and manually move the valve actuator to make sure it’s not stuck… alternatively just go back to OPC and ask then to check it over. Edited by TDT on Wednesday 23 February 18:36

TDT said: There is a power dip at around 5k on the stock car when you look at the dyno charts… Some people can perceive it… other not so much. Here is a comparison of stock 981 GT4 (red) to stock 718 GT4 (blue) Can easily be tuned out with just an off the shelf map or other options if you have an appetite for light modifications. As for your PSE valves… you’ll just need to make sure they are operating correctly on both sides… as it might be that only one is working. With the car off.. turn the key in the ignition just to power on but not start the car. Open window or door. Press the PSE button and you should hear the valves open. If you’re not sure you can have a look under the car and manually move the valve actuator to make sure it’s not stuck… alternatively just go back to OPC and ask then to check it over. Edited by TDT on Wednesday 23 February 18:36 Thanks. So I wasn’t going mad then. I got one my kids to press the PSE button while I stood outside. I could notice it getting somewhat more bassy/loud. Couldn’t tell the difference when driving though - perhaps I will tell the difference over time once I get used to all the noises the car makes. Am I right in thinking the ESC off just increases the amount of slip but doesn’t actually disable any of the stability components? Thanks !

ESC Off is exactly that, stability control off… TC Off is traction control.. GT4 has very good electronic systems, and not intrusive unless you are actually doing something wrong. The car will let you get some angle even with it all left on in default. Edited by TDT on Wednesday 23 February 19:11

TDT said: ESC Off is exactly that, stability control off… TC Off is traction control.. GT4 has very good electronic systems, and not intrusive unless you are actually doing something wrong. The car will let you get some angle even with it all left on in default. Edited by TDT on Wednesday 23 February 19:11 Brilliant thanks

TDT said: ESC Off is exactly that, stability control off… TC Off is traction control.. <snip> GT4 has very good electronic systems, and not intrusive unless you are actually doing something wrong. The car will let you get some angle even with it all left on in default. Have to say the first time I discovered how loose my 981 GT4 let me get everything on slippery roads I was slightly taken aback - even with everything left on. But like TDT says, very quickly got used to it, and unless I do anything silly it very smoothly steps in and keeps me out of harm's way (so far). Similar to other comments, the noisy exhaust switch does less than I had expected, but definitely does something at idle, and a little more when the revs and throttle opening are greater than can be exploited very often on public roads. It's less than subtle, but definitely not "night and day". Liam

Should’ve asked if it was a 981 or a 718 as I don’t know much about the 981 and it’s power dip at 5000

Sticking valves on the PSE is a common complaint and a warranty item. You can check manually if they are operating by getting underneath and either seeing them 'switch' or operating the rod by hand to see if they're free. If it's a 981 bucket then yes the central pads do velcro out and from memory there is a 'butterfly' piece of veclro that goes through the harness slot and you may be able to release it from underneath to tease it out. Not noticed any issues at 5k other than the glorious engine/exhaust sound!