The specs are at the crank, 295bhp. I would expect around 250bhp at the wheels. There’s lots of factors including the dyno, some dynos read lower, some read higher. On the engine rebuild, you wouldn’t lose 30 or 40 bhp. They also check all the parts before using them. If you’ve had new pistons and cylinder sleeves then I would still expect a good number.
230 at wheels though, not the same as "at the crank" 295 quoted by porsche. It's probably the tiptronic sapping the power, I'd say 250ish is where you'd expect to be at wheels with a manual. You have had a top end hartech rebuild and I know you said not a full rebuild but I know from your prev videos you had the full deal done at hartech (I.e not just half a bank or just 1 cylinder) so you should expect a healthy engine making factory levels of power, which it probably is with the gearbox out of the equation, the gearbox of course has not been rebuilt. In conclusion I'd be happy as well, as you are too.
Yeah I do think it’s that gearbox letting it down. But like you said at the crank is what is quoted and I suppose it’s totally irrelevant as it doesn’t reach the road.
@@JoeTalksCars True, but I suppose also what the gearbox is sapping in power it makes up for in driving efficiency i.e more likely to make perfect gearchanges everytime and I you have longer ratios. Enjoyed the recent alignment video too, very imformative and not such a "black art" as first seems.
Something has gone wrong with your dyno run. If you look you will see the brake lights coming on during the run and the rear left hub actually stops turning at one point. My guess is the traction/stability was not switched off and was kicking in, giving you the incorrect results seen.
So this was my editing. My camera man lost the plot and filmed the floor. Due to having one go at this I had to use what I had but wanted to share the sound. I knew a couple of people would spot it 🤣 at least there is nothing wrong with the car other than it’s a Tiptronic and that’s what’s robbed the power.
If you add 18% to the figure witch is typical drive train losses it comes to approx 275bhp at then crank. Not far off the 295 quoted from the factory. You only had the bottom end rebuilt not the heads, cams and exhaust, so not bad for the age of the car imo. Go to another dyno and you could easily see another 10bhp.
That’s good then really, a good service, new plugs and coils and I may make a little bit more back. Thing is, the car feels fast to me which is all that matters I guess.
Probably down to the slushbox. Contrary to what you say about wear and tear, there's no reason why it shouldn't make full book power. I'm sure it's making much more power than 230hp. Just another reason to avoid the awful Tip box.
That's normal for a car with 295 on the crank through an automatic gearbox. Lots of losses through the Mercedes auto box. That works to 171Kw at the wheels, where I live an SLK 55 AMG made 203Kw at the wheels through a similar Mercedes auto box but a 7sp, which is a big drop from 254Kw crank, a loss of 51Kw, your car is 217Kw at the crank so a loss of 46Kw which make sense. Best bang for buck is a IPD plenum and throttle body+tune for a 987.1 which should see good gains along with a BMC filter and maybe new/cleaned injectors+ plugs?
That’s really interesting thank you! Forgot it’s the Mercedes box. Yeah so it shows they rob power, I mean I wouldn’t swap it for the easy of use but surprised how inefficient they are.
Hello from Germany .. when you hit the Autobahn .. hold her on the left ... and enjoy it... there are many reasons for the lost power over the years .. starting with sparkplugs to coils and so on .. but for the age its ok...
Too bad to hear that not much power came out, I also have a Cayman S from 2006 and have 345 hp on the dyno due to the carbon MRN intake and carnewal exhaust If I were you, I would first check whether your coil packs have already been replaced with the better version of BERU, probably one or two of them are breaking
230 + 14% = 262 @ flywheel, so how much is the dyno on the conservative side and how much is father time in the differential 🤔. I don't know if the Tiptronic consumes more than a standard transmission either.
Yeah that makes it seem a little better. You are probably right about the Tiptronic box tho. Probably robs power as it does affect the mpg. Wouldn’t change it tho, love having a point and shoot car. Probably because I’m a bit lazy🤣
Plus whatever you lost through heating up your differential gears by virtue of the left hand wheel being static at full throttle... nasty. You have a traction control issue, or a siezed brake, or a very poorly differential!
So that was the edit. Well spotted but my camera man lost the plot and filmed the floor. I took the sound and overlayed what footage I have. Hence the sound of acceleration and the wheel not moving in time 🤣
@joe Can’t see the graph properly to see the RPM values but it definitely seems to drop off quite a bit in the upper quarter of the power band. You can see the torque suddenly drop and hence the power isn’t climbing with the revs. This seems to correspond with the brake lights seen against the roller door in timing with the hub dyno braking. It works by eddy braking and measuring the force to do this and thus overcome the cars torque. Be aware that hub dynos have lower frictional losses so everyone’s comments amount adding xbhp on to get crank BHP isn’t necessarily true, although yes your value is net not crank and your engine will be making more. The chassis dyno has more frictional losses. In other words don’t think you can just add on 50bhp to your 230 wheel value. It will be a lot less than that. However the operator should have gone through this with you and a drag factor calculated. If you can pull some figures from the graph, look at what RPM the peek power is produced at. Porsche quote around 6250rpm is where the max power is made. After that it’s tapering off. Where was yours? If your max power was before this point I’d consider an issue at the top end either with fuelling or ignition and the engine pulling back.
So the brakes coming on ect may be a good observation! However this was my silly editing. The camera man lost the plot and filmed the floor, I had to pull the footage I have and use the audio 🤣 peak power has arrived as it should and they said the car was smooth and healthy. To be honest I was more interested to see what it had and to check all was well. I was surprised to see it so low but the Tiptronic box rob power something crazy as most have said.
Was always led to believe 40-50 bhp difference between crank and wheels so that would equate to 270 to 280 which i still think is good for a near 2 decade old car.sounded awesome on the dyno too😊.i think we can all get carried away with evs running nearly 2000bhp ect----this car i wil be great fun on the ring i imagine and still capable of getting you in serious trouble on the road in this country 😅. Plus even with all the work done probably stands the owner less than the cost of a replacement tesla battery 😅.
That’s a great way to look at it. The power of the new ev cars just makes you think 300 isn’t a lot. Or even 600 is seen as ok in the world on ev. This think running such “few” bhp at the wheels still keeps up with more or less everything and on the ring will feel like plenty.
I think when road and race had his Boxster S, he dynoed it and it was low on his as well. I think the main problem is the tiptronic is not designed or efficient on the dyno, hence the lower readings. I dont think the car has lost power, especially for what you paid for the rebuild. I would personally look at testing the 0-60 and compare that to what Porsche and others have got with tips as well, that may give you a better understanding of the power?
Chipwizards do the remaps for Hartech on their oversized engine builds. Wheel HP will always be lower than the crank HP quoted by manufacturers but maybe take it to them and see what they can do with it. With your sports exhaust now fitted it may need the map tweaking to get the best out of it
@@JoeTalksCars indeed 👍. Are you doing Goodwood festival of speed again this year, Joe. I know it’s a bit of a trip for you. I’m kinda hoping it’s not the wash out it was last year 😂
After my 987 3.4 rebuild to 3.7 had a gt3 tb and topgear exhaust with 200cel cats and a custom remap and getting 355 at the wheels with valves closed and 365 at wheels with valves open
Total for it was £17,229.30 including vat This wasnt just the rebuild had a drive shaft replaced at same time and a raditor and ac condenser labour came to £5,220 + vat parts Supplied by garage came to £9,143.60 +vat that included drive shaft and ipd 82mm gt3 throttle body kit and radiator and ac condenser i supplied the top gear exhaust and 200 cell cats i think they was around £1,900 including vat
So you changed the exhaust and didn’t remap ? Why just do half the job ? Cough up and get it finished properly.. the car needs to breath properly also so do the air filters … should’ve left std if your not doing the full job. 🤷🏻♂️
He's only done the back boxes, not the headers. The back boxes will mkae zero difference to performance and remapping for them is pointless. Changing the air filter will likewise do nothing.
