Cayman/Boxster S 3.4 987.1 - 200 cel headers - Page 3 - Boxster/Cayman - PistonHeads UK

Hi. Has anybody got first hand experience of the options that are out there. I haven't got loads to spend so was looking at, - Carnewal OEM converted/exchange at about £750. The pro's being fit should be perfect as OEM and they are cheap..Cons are they weren't a great design from Porsche with unequal length headers so not great for optimum performance, prob mild steel, prob heavy.. - Topgear 200 cel sport headers at about £1000. Look good but hear varying reports. The pros being they are stainless, equal length headers, poss lighter than OEM, ( not sure on the last point? ). The cons are that design911 website states "not an exact fit for 3.4 model due to slight difference vs 3.2 and may need slight modification to avoid blowing " Not sure which option to go with but would welcome any feedback from people who've fitted Topgear option to a 3.4ltr or any alternatives that seem to fit well but don't cost much more than £1250 ish.. Anyone tried Design Tek option? Cheers, Ed

Anyone? Might go for it whilst the lockdown is on if I can get delivered as if ever there was a time to do it it's now..If bolts look too corroded I may bottle it and wait to take them to an indi with ramps/gas/skill but no harm in having them ready.. Only other concern is world meltdown and wishing I hadn't spent the cash but then I guess going down in noisey blazing cayman is a decent way out..!?

On those cars the best mod is a cat back exhaust as that section has 2x 400 cel cats in it, which can be totally removed.

Thanks guys and fyi car already has Csrnewal GT which I believe is cat back mod. Agree cmoose the stock design looks shocking and as if it was deliberately designed to stifle. Gert at Carnewal advised 3.2 is equal length and much better but I would need to track down a set and send to him which seems a bit pointless if for not a lot more I could buy stainless..I might call Topgear tomorrow if the are open to see why they blow on 3.4?

I run "race headers" on my 3.4 981 S.

Yep good 3.2 manifolds would be good if I could find them. Watching the "induction mid myths" vid and pouring over forums fries my brain to be honest...So much conflicting info out there.. Not sure if Cayman was more restricted to avoid stealing thunder from 911 and therefore would offer better gains from better breathing, ( or whether that's well told folklore best on a nice plausable theory ) I know any gains will not be huge but as mentioned I really wanted better throttle response, removed flat spot, a bit more noise predominantly. If I could find 25hp along the way then great but there seems to be very few "proven" videos etc out there. I would say the remap prob required to optimise any mods but even then theres plenty of folk saying the stock ECU will adjust...

Edmundo2 said: Yep good 3.2 manifolds would be good if I could find them. Watching the "induction mid myths" vid and pouring over forums fries my brain to be honest...So much conflicting info out there.. Not sure if Cayman was more restricted to avoid stealing thunder from 911 and therefore would offer better gains from better breathing, ( or whether that's well told folklore best on a nice plausable theory ) I know any gains will not be huge but as mentioned I really wanted better throttle response, removed flat spot, a bit more noise predominantly. If I could find 25hp along the way then great but there seems to be very few "proven" videos etc out there. I would say the remap prob required to optimise any mods but even then theres plenty of folk saying the stock ECU will adjust... My 3.4 987.1 ended up with 345bhp and no flat spots. Was a great drive. My 987.2 has 350bhp. The 981 3.4 will goto 380bhp.

Thanks for info. Do you mind me asking what mods lead to 345bhp with no flat spot? My car currently just Csrnewal GT which I believe is just rear silencer mod.. Thanks, Ed Porsche911R said: Edmundo2 said: Yep good 3.2 manifolds would be good if I could find them. Watching the "induction mid myths" vid and pouring over forums fries my brain to be honest...So much conflicting info out there.. Not sure if Cayman was more restricted to avoid stealing thunder from 911 and therefore would offer better gains from better breathing, ( or whether that's well told folklore best on a nice plausable theory ) I know any gains will not be huge but as mentioned I really wanted better throttle response, removed flat spot, a bit more noise predominantly. If I could find 25hp along the way then great but there seems to be very few "proven" videos etc out there. I would say the remap prob required to optimise any mods but even then theres plenty of folk saying the stock ECU will adjust... My 3.4 987.1 ended up with 345bhp and no flat spots. Was a great drive. My 987.2 has 350bhp. The 981 3.4 will goto 380bhp.

Well I've gone ahead and ordered IPD plenum, 82mm TB and Design Tek filter/intake system. Call it retail therapy..? Already have Carnewal GT rear silencer so hope better induction will compliment this and yield a bit more power. Some say stock ECU will alter/learn and adjust fuelling to suit with some driving, others say it will need a remap... Hard to know but will take a view once the lockdown is lifted and ponder 200 cel manifolds and remap then.. Should certainly sound a bit better from the cabin if nothing else..

Had an enjoyable time tinkering today, ( a welcome release from boredom ). IPD plenum, 82mm TB and BMC filter all fitted. All went to plan and fitted nicely. IPD/TB is a bit of a PITA to fit but if you take your time it all goes together ok..BMC is straight forward and a good fit.. On start up it seems all is good with nice steady idle and no lights on the dash. IPD instructions advise that it may take 5 - 50 mile drive for things to really settle down as ECU re-calibrates to accomodate the increased airflow and starts to fuel at correct level. Unfortunately I can't drive it currently but once it was up to temperature I gave it a few blips of 3/4 throttle and it sounded glorious....Unfortunately I then realised that the rear hatch was open hence I was getting full unfiltered theatre but it certainly seemed tuneful..! It's amazing how much conflicting info there is out there re how much or little these mods make so I'll have to wait and see.. Can't wait to get out on the road but will wait until it's sensible to do so. Hopefully it will seem improved and the components all go together with the exhaust to provide some extra poke/responsiveness.. .

Edmundo2 said: Unfortunately I can't drive it currently but once it was up to temperature I gave it a few blips of 3/4 throttle and it sounded glorious....Unfortunately I then realised that the rear hatch was open hence I was getting full unfiltered theatre but it certainly seemed tuneful..! It's amazing how much conflicting info there is out there re how much or little these mods make so I'll have to wait and see . Get a Boxster ..... Did you do a before and after Dyno? Yes there are lots of claims for different mods. Most suppliers and users cannot substantiate the claims. I did Dyno my car standard and at each stage of mods. I stuck to the same Dyno. When I was done, unasked for the Dyno to pull all my individual graphs onto one graph overlaid.

I like the noise and I like an open top but trying to arrive at a real drivers car and I like the Cayman and the chassis/taughtness thanks..Could just remove the rear hatch I guess?? No before dynos unfortunately. I figure mods either do or don't improve things and I'll only find out they don't when I've done them so it is what it is...The air filter/ bigger TB/ smoother flow plenum make sense on paper if exhaust also freer and can clear more gasses..I may get it dyno'd at some point but prob only at time of mapping if I go there as they go hand in hand...My gut instinct is 200 cel headers, ( wait for covid to clear before getting it on ramps to look at bolts ), and lightweight flywheel would be worth getting in place before spending money on a dyno/remap...What I'd really like to understand is how OEM ecu adjusts to such mods and whether it's enough or whether a remap brings much more? How did yours end up? Better or worse than expected? What spec did you arrive at? Ed edc said: Get a Boxster ..... Did you do a before and after Dyno? Yes there are lots of claims for different mods. Most suppliers and users cannot substantiate the claims. I did Dyno my car standard and at each stage of mods. I stuck to the same Dyno. When I was done, unasked for the Dyno to pull all my individual graphs onto one graph overlaid.

anonymous said: [redacted] I don't quite agree. I think the thing that matters most is whether you achieve what you want. If that is enjoyment of the mod process itself that's great. If you want pub bragging rights or are genuinely interested to see if the mods make a measured difference then some sort of Dyno or measurement is needed otherwise it's all just guesswork. It could be a 30-70, a 1/4 mile or whatever. Bum Dyno is ok if you can't be bothered with any of the above but just want some comfort and feel good factor that you haven't wasted your money 😁

Indeed. Can't feel s t right now! Not expecting loads from any bolt on bits... I've not had the car long and still have a lot of aquainting to do to appreciate the car as is before any changes... I've not looked into real mods in terms of bigger displacement/cc, cams, cranks, pistons, etc but I assume it's all crazy money and more than the value of the car to the point it's cheaper to go buy a GT3...? On the basis I can't afford that and the car is really nice already I think maxxing the breathing + improving throttle response for a couple of grand is a reasonsble approach..The chassis/suspension are mega too so perhaps just a few brake improvements to complete the picture.. Exciting and visceral is the aim and if some of it comes in the form of noisey placebo then that's ok...If its quicker as well then great

Edmundo2 said: I reposted my Dyno and mods in this other thread https://www.pistonheads.com/gassing/topic.asp?h=0&... This was over 6 years ago now. I've only tried different cats since 2013 trying a pair of second hand 100 cell then some new 200 cell. In between was a few months back to the standard ones but all the time with the eBay manifolds.

I'm not sure what other mods are on your maybe list but I would research in no particular order: DIY or aftermarket poly gearbox mounts. Rear adjustable toe links GT3 brake ducts, very cheap to do. Fresh engine mount Underdrive pulley Needle bearing shifter. These are all cheap to do.

Yes some of those on the list..GT3 brake master cylinder and giro disc possibly...Also rennline throttle pedal to improve feel..Will wait to get more familiar with it before doing much more.. These are on the way too which can make quite a difference !

Best off with a straight through pipe with these as you don't need them. No MOT problems and less restriction/cost than anything else Dunc.

With already having Carnewal GT rear section would that not mean it was completely without cats? I would assume this would be an MOT fail if so? dunc_sx said: Best off with a straight through pipe with these as you don't need them. No MOT problems and less restriction/cost than anything else Dunc.

My 3.7L 987.1 Cayman S had a Miltek de-catted rear section when I bought it. I started to get a blow from the headers, and when they were removed I discovered that the primary cats had been emptied, so I had been running with no cats at all. I subsequently replaced the headers with new Top Gear straight through pipes and the car has been through three MOTs since. Apparently it does need a "sympathetic" tester It also still manages to pass 101db trackday noise tests. In short it does seem you can get through an MOT with no cats.....

Quick update to say I took the cayman on a short sensible run to buy shopping this evening which gave opportunity to sample the newly IPD plenum, GT3 throttle, BMC filter. My initial thoughts.........undewhelmed. As mentioned before I wasn't expecting much and I was aware of conflicting reports re any gains. My hope was the throttle response might have been a bit better, there may have been slightly better power and the noise may poss have been a tad louder, ( induction at least ). To be honest I can't detect any of these currently. I probably only drove 15 miles and nothing hard. Some say it takes a while ( up to 50 miles hard driving ), for the ECU to adjust to the new increased air supply and start fuelling accordingly. I'd love to find this is the case but I can't see why this would be or why it wouldn't adapt quite quickly? We will see... Still tempted to go for 200 cel headers , lightweight flywheel, remap in the future to see if they help create the desired effect and help bring it all together but will see how Covid19 winds up first. ( Incidentally the new Puma Sparco Speedcats are superb and the most noticeable improvement on the drive! ) Edited by Edmundo2 on Thursday 9th April 23:10

Headers and map will make the most difference.

The throttle is now about 15 inches closer to the heads as it fits at plenum end not MAF end like stock. Either way what I need to fathom is whether they are worthwhile and will yield better results than stock parts if I go on to get headers and remap? If not then ???? Any advice appreciated. Ed

Yep the more I dig the more I find poor results being reported. Headers it is..

Edmundo2 said: With already having Carnewal GT rear section would that not mean it was completely without cats? I would assume this would be an MOT fail if so? Hi Edmundo, My 2007 Cayman S didn't have any CATs and I didn't have any MOT problems, couldn't promise that would be the case for all cars though. It went much better however

Ok, I have x1 manifold off and I suspect they've been off before so hoping the other side comes away as easily. I've bought Topgear 200cel headers and I have to say the quality looks great. I hope they fit as well as they look but will see. One question to anyone that's done similar - Did you use the gaskets provided with the aftermarket exhaust or did you go OEM?

AJB88 said: Headers and map will make the most difference. this.

Yep car will likely go to Chipwizards

Well thats them all fitted. Topgear stainless 200 cel manifolds + decided whilst it was in bits to add new AWE twin chrome tips. Just been out to do the grocery shop and I can confirm the car is louder and feels more responsive. As others have said it just feels freer and less strangled. I still find I need both windows open to really enjoy it, ( may try desnork to see I'm can improve things further on that front ), and wasn't giving it the absolute beans but its deffo worthwhile. I poss have a very slight ticking so I may need to tighten the bolts further but there's a couple that are a pig to get to + I did air on the side of caution and didn't reach the 17ft lbs torque setting as it seemed bloody tight and I was conscious I was bolting stainless steel into alloy and the thought of stripping the head when I got so lucky removing the old studs didn't bare thinking about. I should trust the setting but better safe than sorry so will give them another go now been through a heat cycle.. I have to say I'm really impressed with both parts fit/finish/service so hats off to both companies..

Glad to hear you like them, I guess a remap will bring out the best in them. Think I will get a set at some point for mine.

Good job. Once you get a good run in you will hopefully find a similar effect as the 986 in that it just revs a lot cleaner and more freely especially at the top end.

edc said: Good job. Once you get a good run in you will hopefully find a similar effect as the 986 in that it just revs a lot cleaner and more freely especially at the top end. Yes I can sense that already and it feels much nicer in the top end. I'm still going to work on the lower rev range as this is where I want the gains. Hopefully a dyno/remap will help this. I'd really like the lightweight flywheel at some point too....

Congrats, on doing this. Great thread... enjoy it.

I can't quite believe I'm saying this but upon getting the car back on the stands to re torque the manifold bolts one of them has sheared!! I'm properly gutted and confused. At no point has the torque wrench clicked and the thing is set as close to 204 lbs in/2.35 k m as I can get on my torque wrench which equates to 17ft lbs recomended? Either it's not close enough, the torque wrench is crap or not calibrated correctly, I've done something wrong, or the bolts are crap...? The first time around I aired on the side of caution but when I heard a very faint ticking I thought a re torque was worthwhile just to finish the job. Indeed all the bolts on first bank did feel loose second time around so I think it was worthwhile and the right thing to do but cant believe I've snapped one... I asume it will now blow therefore it will have to come of and be extracted? It looks like there's some material proud of the head so can only hope with the manifold off it can be turned out as it's new and there's copper slip on the threads? It was going far too well....Definately time for a beer now...

Too bad. Was the thread clean?

Yep. Nothing crossed. All went in perfectly with fingers to start with and nipped up no problem. The torque wrench is not really the right range for such a job I dont think but I think the conversions were right and I worked slightly on the low side when rounding up etc..?

Not sure what force you would expect would be required to shear a brand new stainless bolt like that? I would have thought you'd strip the threads in the alloy head before a brand new bolt would shear? Edited by Edmundo2 on Thursday 30th April 22:58

That's what I thought. Yes I seemed to have to put a bit of effort in but I thought that was perhaps just me struggling with the lack of room/leverage space. I should've trusted myself that it seemed too much..I assume the issue is with the torque wrench setting or its calibration? Really annoying but I'm just going to have to put it behind me and get on with it...Tempted to take it to my local garage to get it on ramps and whip it off and hopefully, hopefully get grips or sn extractor on what's left...Will then use his wrench to torque them.. Edited by Edmundo2 on Thursday 30th April 23:25

Thanks for the sympathy cmoose. Yes f**ing stupid me! Last year I was using a different torque wrench in our race kit. We used it before every run on the centre lock wheels on the race car we were running.. Since selling up and buying the croc my old man and I split back our tools out of our joint race kit. As a result I only had mine when it came to doing this job. I've never really had much use for it and the scale is far to broad to get highly accurate settings but I should have been close enough...Therefore I think it's either massively out of calibration or its knackered. I would've just gone on feel but because the Top Gear gaskets looked quite thick I thought they may crush a bit hence kept going with the torque wrench when the bolts seemed to br getting tight. Just have to remind myself how much I like the car, how lucky I was the old bolts didn't all shear , and that vs the current global catastrophe it aint that bad...

Just to update here. I got the car to race engineer who got it on ramps and removed the new snapped stud easily by drilling a small hole in it and then just turned out with a screwdriver... Saved a lot of hassle and didn't remove a thing. On checking the remaining bolts they were all over the 17ft lbs torque setting so clearly my wrench is way out or buggered.. Anyhow before getting it off the ramps we listened, ( whilst social distancing i might add ), for the ticking I thought I could initislly hear on first test run but all seemed good so we dropped it down and away I went.. As soon as I set off I noticed the ticking again. Nothing at idle and disappears or gets drowned out at higher revs but when crawling about on a bit of throttle its there..So my question is , what's causing it..? The one thing I noticed when fitting the AWE tips was a very small crack where one of the top connecting pipes links into the near side back box. It's at the edge of a weld which I think is poss re welded from Carnewal GT mod? About 10mm long and 1mm wide crack. I assume it poss cracked when being pushed or pulled apart? If so it could have happened whilst I was fitting these bits hence the ticking wasn't there when the OEM headers were on.. I assume that's the sort of thing that would cause a "tick" noise rather than a breathy blowing? So I'm hoping that's it and will try a little bit of JB weld to see. If so will get it TIG'd up properly. If not then I'm not sure. I'm hoping the TopGear gaskets are all ok and as we know the bolts are all done up plenty tight enough! Not sure if anyone has past experience of similar or stories of non OEM gaskets bring the issue/more likely culprit? Cheers, Ed

Hi @Edmundo2. Appreciate this thread is rather old now but am I thinking of some exhaust mods for my 987.1 CS and it looks like the optimum route is a cat back exhaust and new headers as well, like the Top Gear 200 Cel ones. Just wondering how loud the exhaust is with Gerts cat back mod and the Top Gear 200 Cel headers. Is it significantly louder than stock? Also, have you had any problems getting it through the MOT? Thanks

Hi Westy. Its hard to say how much louder it is than stock as my car had the Carnewal on it when I bought it so whilst I couldn't compare back to back it did have a lovely noise to it on first aquintance.. I wanted a real ripper so added the Top Gear 200 cel manifolds + desnorked and BMC filter..This made quite a difference both in terms of the level and pitch of the noise but also in terms of the way the engine feels..The first time I took it out with the manifolds fitted it just seemed a lot freer and sort of unlocked as if the old stock bits had been strangling it...Coming off throttle it seemed to coast much better/more easily as if there was previously some back pressure/engine braking going on..I'm not sure if that was the case as I'm not an engineer but that was the sensation.. I love it now...It's reasonably loud stood outside the car at tick over but a nice level in the cabin...On the move it's noticabley gruff under light load but as soon as you settle to a cruise it's very civilised really and not droney in anyway and you can hold conversation no problem..It's on 718 wheels so a bit bigger than standard which probably adds a bit of extra road noise which most Porsches do.. However if you drop a cog and wind it up it absolutely screams. It's a fabulous noise....a properly 70's sports racer type tearing noise that is reminiscent of on-board shots you see from flat engine cars back in the day.. It depends what you want it for I guess...I've tried running without the engine cover to get even more noise but that's probably doesnt appeal to everyone.. Ref the MOT it was no problem. The only issue I have is I get an engine warning light ever now and again. I tried to sort it by getting pedestal/extenders put on the lambda sensors..It hasn't seems to resolve it so I just cancel it with OBD plug in when it happens and I think I'll be able to get it switched off for good when next in at my Indy... To sum up it's great and really brings the car alive but it remains useable..Also I was really impressed with the fit and finish of the Top Gear product..Amazing quality for the money..If doing it make sure you replace all bolts with Stainless or go for titanium studs etc..In addition buy OEM gaskets and use those instead of the Top Gear ones as the seal better.. I've since gone further with LWFW, LSD, 964RS mounts etc which only add to the sensation but I'd deffo start with the exhaust. Hope this helps and good luck if you go with it.. PS. If ever your in Leeds I'll gladly let you here it etc..

The above sounds ace. Hoping to pick mine up in next couple of days with 200 cell and full exhaust. Waiting patiently in anticipation of some nice weather this summer!!

Thanks for the detailed reply @Edmundo2. Seems you have done some fairly extensive mods - not sure I will go that far but it is interesting to hear about. It would be great to hear your setup & thanks for the offer but I am too far south really - based just north of Cheltenham. How did you get on fitting the Top Gear header tube - you mentioned it wasn't good fit on the 3.4 and might need some modification? @jayxx83 which exhaust have you gone for? Cheers

Westy65 said: Thanks for the detailed reply @Edmundo2. Seems you have done some fairly extensive mods - not sure I will go that far but it is interesting to hear about. It would be great to hear your setup & thanks for the offer but I am too far south really - based just north of Cheltenham. How did you get on fitting the Top Gear header tube - you mentioned it wasn't good fit on the 3.4 and might need some modification? @jayxx83 which exhaust have you gone for? Cheers Hi. The TopGear fit was pretty much faultless. I showed them to a race engineer who was amazed that you could buy a pair for £1k... The only point of note is that if you are using flange head bolts the flange may foul against the edge of the outer pipe. Not a big deal but just check so that you don't think you've tightened it down to find you haven't. Just needs the flange grinding down or would be ok with cap head bolts and smaller washers instead..Consensus is that Titanium studs with flange nuts is a better option as avoids them getting rusted into heads in years to come but I couldn't source quickly at the time so figure stainless bolts would be perfectly good.. Edited by Edmundo2 on Tuesday 9th March 20:00

Westy65 said: Thanks for the detailed reply @Edmundo2. Seems you have done some fairly extensive mods - not sure I will go that far but it is interesting to hear about. It would be great to hear your setup & thanks for the offer but I am too far south really - based just north of Cheltenham. How did you get on fitting the Top Gear header tube - you mentioned it wasn't good fit on the 3.4 and might need some modification? @jayxx83 which exhaust have you gone for? Cheers i went for an M&M one from Germany https://thumbsnap.com/sc/vxRTutrG.jpg https://thumbsnap.com/sc/BRz6swPe.jpg i believe they make the exhausts for techart, manthey and a load of endurance racing teams. it was second hand but an absolute bargain. Got it for £750 delivered to the UK. They are over £5k new. Hoping it unplugs the factory corkage and Edmundos comments above certainly suggest that will be the case. Hopefully picking up on Thursday all being well!

Decided in the end to go for the single most cost effective upgrade in my mind which was a remap. Just had this done by DMS Automotive and managed to get an extra 25 bhp for £600. Any more money I would have spent on upgrading I will save towards the next car.

Westy65 said: Decided in the end to go for the single most cost effective upgrade in my mind which was a remap. Just had this done by DMS Automotive and managed to get an extra 25 bhp for £600. Any more money I would have spent on upgrading I will save towards the next car. Blimey. That sounds like a massive increase? I went to Wayne Schofield at chip wizards who is very highly regarded and he warned me I met only see a few bhp. This was the case so for you to see 25bhp is baffling/encouraging..

Apparently they have created their own tuning remaps specifically for different cars which is why they can get these results. I was quoted a 10 bhp increase from a “standard” remap garage but didn’t think that was worth it.

Hi Westy65, How does the car feel after the remap?

To be honest I haven’t driven it much since. The roads were busy on the way back so no real chance to test it out. I did see a small increase in mpg but I’m putting that down to a slow cruising speed rather than the remap. Since then I’ve been working from home and have hardly left the house! I’m not expecting to feel much of a difference really, given we are only talking about an 8% approx increase in power but I will let you know when I have more to report.

Remap on my 981 S made a big difference as gained the GTS power. Stage 2 with headers was fun.

Edmundo2 said: Westy65 said: Decided in the end to go for the single most cost effective upgrade in my mind which was a remap. Just had this done by DMS Automotive and managed to get an extra 25 bhp for £600. Any more money I would have spent on upgrading I will save towards the next car. Blimey. That sounds like a massive increase? I went to Wayne Schofield at chip wizards who is very highly regarded and he warned me I met only see a few bhp. This was the case so for you to see 25bhp is baffling/encouraging.. I would trust Wayne Schofield to know ... I am guessing that he has plotted a lot of promises ...

AJB88 said: Remap on my 981 S made a big difference as gained the GTS power. Stage 2 with headers was fun. AJB88 who did you go with for the remap/stage 2?

pec996 said: AJB88 who did you go with for the remap/stage 2? Mine was the off the shelf COBB Stage 1 and 2 software. I did speak to Unicorn Developments as they offer custom tune using the COBB device but never got up there.