A new pair of ser­pen­tine three-branch­man­i­folds now adorn the ex­haust ports of Johnny Ti­pler’s 986 Boxster S, treat­ing the world to an acous­tic ca­coph­ony of the rau­cous kind

911 Porsche World - - Practical Porsche -

Mo­tor­ing to Le Mans Clas­sic last month, I wanted to make as much noise as pos­si­ble. Not con­tent with merely hav­ing the Boxster look­ing good in its new Etna Blue colour scheme, I wanted it to sound the part as well. New man­i­folds and a cat­by­pass were the ob­vi­ous way for­ward.

A Car­graphic si­lencer fit­ted at the firm’s Cul­lomp­ton fac­tory last au­tumn high­lighted the sadly cor­roded con­di­tion of the rest of the 986 S’s ex­haust sys­tem. Now 15 years old, I shouldn’t have been overly sur­prised. But the pris­tine ovoid cylin­der showed up the rest of the sys­tem for the crum­bling an­tique con­coc­tion it had be­come. While it was still ser­vice­able, I vowed to get it re­placed with new man­i­folds – and, while we were about it, cat-by­pass pipes, too. A call to Ian He­ward at The Porscheshop sourced a pair of three- branch man­i­folds, as well as the cat-by­pass tubes. It seemed cheap­skate not to match the ex­haust head­ers with a 986 S in­duc­tion kit, so Ian in­cluded the mak­ings for that in his Eurocupgt pack­age, too, plus all the ap­pro­pri­ate gas­kets, studs and bolts.

We’re blessed with one or two good Porsche spe­cial­ists in Nor­folk, but one I hadn’t tried pre­vi­ously was Holt-based high-end spe­cial­ist Tro­feo, whose techies Mike Roberts and Gra­ham Heels are steeped in the finer points of Porsche en­gi­neer­ing. The Boxster was duly booked in, dis­plac­ing a Cay­man up on one of the two hoists.

The first task was re­mov­ing the old man­i­folds. I wasn’t sur­prised that Mike had to re­sort to the dark arts to undo the re­tain­ing nuts. ‘They just break,’ he re­ported. ‘And the ones that wrung off didn’t break dead flat, so we have to take them back with the (Black and Decker) Wiz­ard wheel, then we have to

cen­tre-punch them, and we do that free­hand rather than use a clamp, be­cause you end up hav­ing all kinds of is­sues with those.’ Seven out of 12 broke. ‘We did try first with stud ex­trac­tors, but you still can’t get them out, be­cause the heat gen­er­ated in that area just locks the threads, so we ended up drilling yours all out. We’re not al­lowed to use a torch th­ese days; most work­shops have to be flame­less, so we use an in­duc­tive coil heater, and they heat up the metal rather than us­ing a flame; we put them on the studs for about 45 min­utes and then, ba­si­cally, we drill them out. Start­ing with a small drill-bit, you drill through, then you go again with a big­ger one. There’s a lit­tle ridge on the bit that al­lows that ridge to go flush into the alu­minium, and then you put this driver through and it snaps it into place so they can’t fall out. So, ba­si­cally, we re-tapped the threads.’

Orig­i­nally the man­i­folds are shiny, and then af­ter run­ning the en­gine, when they’ve had a lit­tle bit of tem­per­a­ture through them, it tem­pers the colour with a hint of bronze, which looks really nice, and it’s a shame you can’t see them ex­cept when the car’s on a hoist and the un­der­tray’s re­moved. The new man­i­folds are quite sim­ply works of art in their own right, rem­i­nis­cent of the en­twined snakes de­vour­ing myth­i­cal Tro­jan pri­est Lao­coön and his sons in the Vat­i­can’s mon­u­men­tal clas­si­cal tableau of the same name.

The stan­dard fac­tory head­ers come off the ports and head to­wards the rear of the car in more or less a straight line. The new ones per­form sen­sual curves and curl back on them­selves be­fore head­ing rear­wards and con­nect­ing up with the new cat-by­pass pipes. Th­ese by­pass pipes lack the in­stal­la­tion point for the oxy­gen sen­sors: ‘the sen­sors were seized solid but we man­aged to get them out,’ Mike tells us. The new pipework fi­nally joins up with the Car­graphic si­lencer, in­stalled last Au­tumn.

Be­cause the head­ers spread out into a larger con­fig­u­ra­tion than the stan­dard pipework it was nec­es­sary to trim the cor­ners off the un­der­tray in or­der to re­in­stall it. As Mike ex­plains, ‘Your man­i­folds are banana bunches so they come out from the heads and then curl around, whereas the stan­dard ones just run par­al­lel. If we hadn’t done that the man­i­folds would be vi­brat­ing against the un­der­tray, but more sig­nif­i­cantly, they would also melt it.’ Will they pass scrutiny come the next MOT, or will the cat-by­pass pipes mean a fail? Mike is qui­etly op­ti­mistic all will be well.

Down­side, if there be one, is that the oxy­gen sen­sors al­lied to the cats are now ab­sent, so that the warn­ing light is a con­stant pres­ence on the dash and the “go straight to jail” – well, to the garage, any­way – mes­sage pops up when the en­gine fires up from cold starts and the oxy­gen sen­sors are at their most ac­tive. One cau­tion is dis­pensed with by a click of the com­puter arm, the other hid­den with a black sticker. Ever the op­ti­mist, I trust that th­ese un­heeded warn­ings won’t ever re­fer me to a prob­lem of a dif­fer­ent na­ture. Mike Roberts is re­as­sur­ing: ‘That won’t af­fect the per­for­mance,’ he says; ‘in fact it’s go­ing to make it bet­ter: the per­for­mance will be in­creased.’ Amore prac­ti­cal route is to see some­body like Wayne Schofield at Chip Wizards who would doubt­less be able to pro­gramme it off. Could be a run to Manch­ester is on the cards. ‘You might be able to get a soft­ware pack­age from the States to turn it off,’ says Mike, ‘but you’re go­ing to have the warn­ing light come on all the time be­cause the cat’s been taken off, but also if Wayne does it he’ll prob­a­bly be able to give you some more power as well.’ Oooh!

In any case, the new man­i­folds and in­duc­tion kit have cer­tainly made a sig­nif­i­cant dif­fer­ence to the driv­ing ex­pe­ri­ence, both in terms of noise and per­for­mance. ‘They’re tuned lengths so you’re def­i­nitely go­ing to have a few more horse­power,’ pre­dicts Mike. He’s right, no ques­tion. Driv­ing home, there’s an in­stant surge, and it’s as if the hand­brake has been on all this time and now it’s not on any­more, a re­mark­able trans­for­ma­tion. The sound is at first kind of like a bunch of peb­bles rat­tling in a can, but it quickly set­tles down to a six-pot throb – till the need arises for more throt­tle, and then we’re treated to a full­blooded gnarly flat-six roar. Mu­sic (of a kind) to the ears.

I no­tice peo­ple turn to look more now – sort of like be­ing a suc­cess­ful con­tes­tant on The Voice – though that could still be down to Spray ’n’ Peel’s gor­geous Etna Blue colour change. Ar­riv­ing back at Le Mans’ Mai­son Blanche camp­site late Satur­day evening would have been em­bar­rass­ing, had it not been for the hard­core racket of the Plateau 6 RSRS and 935s tear­ing up the night air. Any­way, the Boxster’s pre­vi­ously boom­ing ex­haust note has dis­ap­peared, which I’m rather glad of as it was a tin­ni­tus trig­ger espe­cially dur­ing ac­cel­er­a­tion. So, say good­bye to Mr Boomer, and hi to Mr Raaaasspurrrr!

Phew, what a scorcher – as the fa­mous but prob­a­bly apoc­ryphal head­line has it. It doesn’t seem very long at all since my en­thu­si­asm for work­ing on any of the cars was de­ci­sively damp­ened by first the win­ter rain and then the so-called Beast from the East (a few cen­time­tres of snow in mid-march, ba­si­cally), but we have now ‘en­joyed’ many weeks of blaz­ing sun­shine that in prac­ti­cal terms have much the same de­ter­rent ef­fect. I know you guys in, say, the south­ern USA or the Gulf states will be all too fa­mil­iar with that sce­nario, but for we Brits it’s rare to have two con­sec­u­tive days above 75 de­grees Fahren­heit, never mind two months. But I have man­aged to get quite a lot more done on the 924S, be­fore it all be­came a bit too haz­ardous to health, and luck­ily my drive­way is in any case shaded by the house un­til about mid­day. Si­esta time af­ter that...

My first achieve­ment, af­ter my previous wide-rang­ing re­port, was to fit the new rear-win­dow perime­ter seal that I have had in stock for ages, and then, prompted by the fresh rub­ber’s nat­u­ral ‘bounce’, to ad­just and ul­ti­mately to re­place the two lock­ing pins that project down into the latch mech­a­nisms in the body. (Just re­mem­bered: I had re­moved both of the latches in or­der to clean, lu­bri­cate and ad­just them one sunny and un­usu­ally warm af­ter­noon in Fe­bru­ary, be­fore the ar­rival of the afore­men­tioned Beast, also tak­ing the op­por­tu­nity to fit new rub­ber seals that sit in the re­cesses di­rectly above the mech­a­nisms. More on both of th­ese items in a mo­ment.)

The pri­mary stim­u­lus to my re­plac­ing the tail­gate seal was suc­cess­fully do­ing much the same with the boot-lid seal on our daily-driver VW Pas­sat a few weeks ear­lier, and that also high­lighted some in­ter­est­ing but at the same time rather frus­trat­ing com­par­isons be­tween the two cars. The VW seal, priced to­day at just £31.98 plus VAT, is a con­tin­u­ous loop, ob­vi­ously made to ex­actly the right length. The Porsche item (£58.13 plus VAT in 2015) comes as a sim­ple strip cut off a long roll that has to be al­most but not quite fully fit­ted, and then trimmed pre­cisely to length as re­quired. That does sim­plify the task in cer­tain re­spects – avoid­ing the need to de­tach the two tail­gate support struts, for ex­am­ple, and per­haps rather more im­por­tantly the wiring to the rear-win­dow wiper – but I do have to ques­tion why, even so, it can­not be man­u­fac­tured such that no ad­just­ment is nec­es­sary.

In both ve­hi­cles the phys­i­cal bar­rier against water ingress past the seal is in sur­pris­ingly large part the sticky, off-white ‘goo’ in­side the metal-cored ‘U’-sec­tion chan­nel that slides over the flange on the body shell. (And the grad­ual hard­en­ing of this stuff is as much the rea­son for ei­ther seal even­tu­ally fail­ing as the rub­ber it­self de­grad­ing. It also means that you can­not re­al­is­ti­cally use again a seal that has been fit­ted and later re­moved.) In the Pas­sat, said sub­stance has from the start re­mained dis­creetly out of sight. In the 924S, though, it im­me­di­ately started ooz­ing out all over the place, and while it was easy enough to clean off the worst of it, there re­main traces on the nat­u­rally slightly por­ous sur­face of the rub­ber. And how­ever care­fully and neatly you cut it – not the eas­i­est of tasks thanks to that metal core – that joint makes the ideal exit point for the sealant. Even now it’s still seep­ing out, espe­cially as the in­side of the cabin reaches melt­ing point ev­ery day, and in­evitably – and an­noy­ingly – it catches my eye each time I look in the rear-view mir­ror.

Prob­a­bly the most im­por­tant as­pect of fit­ting any such seal, how­ever, is to make sure that ev­ery last cen­time­tre of the chan­nel – in­ter­nally ribbed to grip the flange on the body

shell – is pushed fully home. That sounds blind­ingly ob­vi­ous, and on what you might call the con­vex curves around the up­per part of the Pas­sat’s boot-lid aper­ture it was dead easy to achieve. (I left the two con­cave curves right at the top un­til last.) But the Porsche ef­fec­tively has con­cave curves alone, and in that sce­nario it is all too easy to cut the cor­ners, as it were, leav­ing the chan­nel in­suf­fi­ciently tightly grip­ping the full depth of the edge. (And which is in some places not very deep at all.) You also need to make sure, of course, that the edges of the head­lin­ing, and the fab­ric on the rear pil­lars, re­main cor­rectly trapped by the chan­nel.

As for where you po­si­tion the ends of the seal – and hav­ing pon­dered this when I did the job on the 944 last year – I am still un­de­cided about that. It would be a much less per­ti­nent ques­tion if the seal came as a one­piece item, pre­sum­ably as per the orig­i­nal fac­tory-fit­ted part. But logic and ob­ser­va­tion sug­gest at the bot­tom, di­rectly above the tail­gate lock, and that places the sub­tly re­in­forced sec­tions of the rub­ber (they feel as though they have an ad­di­tional ex­tru­sion in­side the ex­ter­nal one) at the lower outer cor­ners of the glass, close to the latch mech­a­nisms. That’s what I did here, and also when I tack­led the 944 last year, and I am guess­ing is what Porsche intended. Per­son­ally, though, I think the sec­tions that most need re­in­force­ment are at the top cor­ners of the tail­gate aper­ture. In the 944 both of those ar­eas of the new seal quickly be­came squashed al­most flat again, and although – so far – the 924S seems bet­ter in this re­spect, there has still been a vis­i­ble com­pres­sion of the rub­ber.

Next, I turned my at­ten­tion to the two latches again – or first to the pins on the tail­gate, to be pre­cise, since I was at that stage rea­son­ably con­fi­dent that the mech­a­nisms within the body it­self were ad­e­quately lu­bri­cated and ad­justed, af­ter my af­ter­noon stint back in Fe­bru­ary. The tail­gate seemed to shut quite de­ci­sively, but even a short test-drive showed that the de­vice on the right-hand side was tend­ing to spring open – or per­haps fail­ing to se­cure the pin would be a bet­ter de­scrip­tion – and there were also lots of an­noy­ing rat­tles and squeaks.

The ob­vi­ous answer was to ad­just the pins down­ward, such that they would lock more se­curely into the jaws of the latches, but both the former were quite badly worn, and the one on the right was com­pletely seized into its mount­ing block, ren­der­ing any movement im­pos­si­ble. Re­mov­ing the en­tire block from the un­der­side of the tail­gate showed why (see photo be­low left). There was no way that was ever go­ing to shift, and so the only solution would be to saw through the old pin, to dis­card both it and the threaded in­sert in­side the block, and then to fit a new pin to a good in­sert that I had saved from an­other car. (They are still avail­able brand-new from Porsche.) Also re­placed were the four small coun­ter­sunk screws se­cur­ing the two blocks to the tail­gate. The finely splined sock­ets in the orig­i­nals were by this stage in dan­ger of round­ing out, and no­tably the new ones from Porsche have much im­proved Torx sock­ets. (T30, for the record.)

Dis­ap­point­ingly, how­ever, all of this play­ing about had for var­i­ous rea­sons re­quired me – against my bet­ter judge­ment – to ease out of their re­cesses in the body the two com­plex (and ex­pen­sive; in 2015 £30.27 each plus VAT) rub­ber seals that are de­signed to min­imise the amount of rain­wa­ter that passes down through the latches. (And de­spite the pres­ence of which it is vi­tal al­ways to re­fit the plas­tic trays be­neath the latches, to­gether with the associated drain tubes that di­rect the water down and then out of the lower whee­larches.) The rub­bers are very dif­fi­cult to in­stall and espe­cially to re­move with­out tear­ing, even with much care­fully ap­plied lu­bri­cant, and un­sur­pris­ingly, de­spite my best ef­forts, both be­gan to split as I eased them out. Which was dou­bly an­noy­ing, be­cause I had only fit­ted them on that Sun­day af­ter­noon back in Fe­bru­ary…

I do have in stock a fur­ther pair of brand­new seals, which once I am sat­is­fied that I have nailed this tail­gate-latch is­sue once and for all I might well use for the sake of neat­ness and com­plete­ness, and ‘clo­sure’ (no pun intended), but at the time of writ­ing my plan is to try re­pair­ing the two torn ones with Su­perlgue, and see what hap­pens. Noth­ing ven­tured, noth­ing gained, and all that. (Stop press: so far, so good, although I won’t be re­fit­ting the newly glued rub­bers, hope­fully for the last time for a very long time, un­til I am 100 per cent sat­is­fied that the new latches that I have since con­cluded I shall have to buy are work­ing per­fectly.)

New latches, too? In­deed. A few more longish drives – and sev­eral dis­ap­point­ingly short ones – showed that, de­spite their now ob­vi­ously cor­rect pro­file, one or other of the brand-new pins was for some rea­son pulling through the jaws (this de­spite their ap­par­ent free­dom of movement and full clo­sure) and, thanks to the strength of the hy­draulic struts,

thereby al­low­ing the tail­gate par­tially to open while the car was in mo­tion. And on at least two oc­ca­sions it opened com­pletely. In the short term I solved that by dis­con­nect­ing the struts, and putting up with the re­sult­ing rat­tles and squeaks, but once I had re­moved the latches (again…) and ex­am­ined them from be­neath, I could see ex­actly what the prob­lem is. The un­der­sides of the jaws have worn into a ta­pered pro­file to match the tops of the old pins, and no amount of ad­just­ment is ever go­ing to pre­vent the new pins sim­ply forc­ing their way through. That’s my the­ory, any­way, but I’ll have to let you know if it works once I’ve stumped up the £80.82 plus VAT (each!) the new ones will cost to buy.

I have had a bit of a re­sult in more gen­er­ally weather-seal­ing the rear end of the car, how­ever. You might re­call that in 2017 I re­moved and re­fit­ted the 944’s rear lights, dis­cov­er­ing in the process that the ve­hi­cle must have suf­fered a mi­nor im­pact at some time, such that at least one of the units no longer fit­ted the pro­file of the body shell quite as well as it should do. It was with some trep­i­da­tion, then, that I be­gan the same task on the ‘S’, which was clearly suf­fer­ing from much the same water (and ex­haust-fume) ingress. No sign of any dam­age, I’m pleased to re­port, but plainly the left-hand unit has been out at least once be­fore, and who­ever did the job had sealed it back into place not with the cor­rect Porsche prod­uct – a spe­cial mas­tic ‘cord’ – but with some­thing that had hard­ened to the con­sis­tency of char­coal mixed with tof­fee. I man­aged to scrape and pick it off both the body and the back of the light unit, cru­cially with­out dam­ag­ing the paint, and thus later al­low­ing rust to take a hold, but re­gret­tably took no pho­to­graphs. I was just a bit too fix­ated on get­ting the job done.

Ei­ther way, I shall take this op­por­tu­nity – and also prompted by a ‘dis­cus­sion’ with at least one Us-based 944 owner on Face­book – to re­mind you that there is a very spe­cific Porsche prod­uct for this task, AND THAT AB­SO­LUTELY NO OTHER WILL DO. It comes as seven in­di­vid­ual rolls wrapped in spe­cial pa­per in­side a brown card­board box (to­tal length 17.5 me­tres), and the part num­ber is 000 043 172 00. At £46.88 plus VAT it’s quite a lot more ex­pen­sive than the com­mon-or-gar­den sil­i­con-based bath­room sealant that is sadly but surely ev­ery modern bodger’s weapon of choice, but the fact is that it is im­mea­sur­ably su­pe­rior in all re­spects.

One other tri­umph was to re­move the re­main­ing body-side rub­bing strips that had been an­noy­ing me since the day I bought the car, way back in early 2012. (Sev­eral were rather wavy, where they had taken a hit, most likely from some­one else’s door, and at least one I had al­ready torn off in dis­gust, af­ter badly cut­ting my hand when wash­ing the car. I’ll leave you to imag­ine the colour­ful lan­guage that fol­lowed that episode.) Trou­ble was, while it was easy enough to pull off the plas­tic mould­ings, they all left be­hind a thick and un­yield­ing strip of weapons-grade ad­he­sive.

I de­bated long and hard about the best way to deal with that, and in the end used some of the ex­cel­lent HG sticker re­mover (, rubbed well into the glue to soften it, and a plas­tic scraper held at pre­cisely the right an­gle. It took sev­eral hours, spread over a cou­ple of days, but ul­ti­mately left no more than a few very mi­nor stains – and, sig­nif­i­cantly, no scratches in the ob­vi­ously still orig­i­nal (and ac­tu­ally re­mark­ably good) paint, other than where a previous owner had rather less care­fully re­moved the strip be­hind the driver’s door, prob­a­bly as a re­sult of the dent which was there when I bought the car. For a while I thought about hav­ing the strips re­placed with a sim­ple flat coach­line, painted or taped on, but hav­ing now seen the body un­adorned, as it were, I have de­cided it looks far bet­ter like that.

And that’s about it for an­other month. The rear bumper has be­come a work in progress – the new rub­bing strip I fit­ted to a re­place­ment mould­ing a few months ago is frankly a bit of a mess; more on this next time – and so too my rear-wiper delete project. It was easy to take the mo­tor off, and I have tem­po­rar­ily plugged the hole in the glass with an ap­pro­pri­ately large flat-headed Torx screw and washer sal­vaged from an­other VW Pas­sat (be­low, mid­dle), although since I doubt that it’s go­ing to rain any time soon I don’t know why I both­ered. (Ac­tu­ally, a good down­pour would be quite use­ful to prove my rear-light seals, never mind wa­ter­ing the gar­den.) Ei­ther way, I shall in due course prob­a­bly in­stall ei­ther the proper Porsche job or else a good-qual­ity af­ter-mar­ket part.

Oh, and I thought I had made a bit of a break­through with the non-func­tion­ing odome­ter, find­ing and then fit­ting the spare that I knew I had stashed away, but ul­ti­mately that’s an on-go­ing saga, too. I man­aged to break one of the two tabs se­cur­ing the lower edge of the in­stru­ment-panel sur­round to the rest of the fas­cia – in fact, I’m not sure that it’s even pos­si­ble to re­move the mould­ing with­out do­ing that – and de­spite du­ti­fully record­ing dis­tance for all of about 10 miles the re­place­ment stopped work­ing, too. I shall have both de­vices looked at by Ju­lian at Reap Au­to­mo­tive in London – for many years the go-to man for Porsche in­stru­ments – and at that point see if I can find a re­place­ment sur­round, too. On­ward and up­ward… PW

The Ti­pler mo­bile in all its new, blue glory at Le Mans Clas­sic

Looks OK, doesn’t it? Left side of the car is def­i­nitely its best (above), and peel­ing off all the body-side strips (see text) has made a big dif­fer­ence to its smooth­ness of line. Pho­tos be­low show the tri­als and tribulations of fit­ting a new tail­gate seal, which un­like on a VW Pas­sat has to be trimmed to length. Cross-sec­tional view of ex­tru­sion (mid­dle) shows white seal­ing goo in­side chan­nel – and the shot next to that how it oozes out, even weeks af­ter fit­ting. Ver­dict: could do bet­ter, Porsche

Where to place the joint be­tween the two free ends of the seal? Logic sug­gests at the bot­tom, and that lo­cates what feels like re­in­forced sec­tions of the outer rub­ber here, at the lower outer cor­ners of the glass (above). I did the same on the 944 last year, though (mid­dle), and the up­per cor­ners of the new seal col­lapsed. Thus far the 924S seems bet­ter in this re­spect, but I shall mon­i­tor the sit­u­a­tion. Photo far right shows new rub­ber seal for one of the tail­gate lock­ing mech­a­nisms, torn when re­moved, but now re­paired with Su­per­glue. Lock­ing pins (be­low) proved to be badly worn, but one of the old ones had to be cut to re­move from its threaded in­sert – and a new one of those sourced, of course. Screws se­cur­ing pin and block to tail­gate were round­ing out (mid­dle), so new Torx-headed items fit­ted, to be on the safe side. Fun and games with latches in body, too, se­cured by stud plates (far right). See also next page

Un­der­side view of latch shows how it is se­cured to stud plate with two M6 nuts – here re­placed with Ny­locs to avoid hav­ing to tighten them so much that they ex­ces­sively squeeze the in­ter­nal com­po­nents. In the event, the latches’ in­abil­ity to grasp the pins was traced to wear on the un­der­side of their jaws (ar­rowed), this proved by slid­ing latch over new pin (mid­dle) and then sim­ply twist­ing. It re­leased far too eas­ily. Be­low: just a re­minder that rear lights should be sealed into the body with this Porsche prod­uct alone for op­ti­mum ef­fect – and NEVER bath­room sealant. Spe­cial screw from a scrap Pas­sat makes a great rear­wiper delete plug: pow­der-coat it, and trim the rub­ber, and it’ll be as good as the costly Porsche part. Don’t know why I didn’t spot th­ese an­cient trum­pet-style horns be­fore, mounted un­der left­hand end of valance. Ei­ther way, they are now his­tory, with au­di­ble warn­ing from the two red plas­tic items – as be­fore

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