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Thefinn
Suzuka


Joined: 11 Jun 2014
Posts: 1038
Location: Essex


PostPosted: Tue Feb 12, 2019 5:40 am    Post subject: Does the 82mm tb upgrade reduce power??????? Reply with quote

Now this is a mod that I have always been an advocate of as when I fitted my larger tb my car seemed to rev quicker and breath easier but have I completely wasted my £££ and reduced power? The reason I am asking is another forum member has pointed me in the direction of the fb post from a renown tunner who suggest this mod make your car loose power in every case.

https://www.facebook.com/100000934727190/posts/2488472351193898?sfns=mo

So my question is and I am hoping some of the other tunners will jump in but I doubt it "are all these mods that we do to our cars such as exhaust and intake actually achieving any gain and does anyone have dyno results to prove it or on the other hand has the socks and sandals crew been right all along and our cars left best alone as Porsche gave us every pony available so the only chance of making them faster is for the driver too loose some weight"

Question
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The Finn's 997 4S progress thread take two

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kas750
Reims


Joined: 31 Mar 2013
Posts: 4432
Location: Chorley lancashire

2006 Porsche 911

PostPosted: Tue Feb 12, 2019 6:29 am    Post subject: Reply with quote

He certainly knows more than most ...
 
  
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Alex
Le Mans
Le Mans


Joined: 06 Mar 2014
Posts: 15956
Location: The Ribble Valley, Lancashire

2000 Porsche 996 Carrera 4

PostPosted: Tue Feb 12, 2019 6:56 am    Post subject: Reply with quote

I spotted that on FB too. Jury's still out unril some more data from other sources is seen.
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MaxA
Barcelona


Joined: 11 Oct 2015
Posts: 1499
Location: Helsinki


PostPosted: Tue Feb 12, 2019 7:40 am    Post subject: Reply with quote

Correct me if I'm wrong, but I thought that for the 9971, you need a larger throttle body, a revised intake plenum and a custom remap in order to add power. And you'll do 'before', 'during' and 'after' runs on a decent dyno to (i) set a baseline, (ii) optimise the remap, and (ii) verify the gains. Dont know
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MisterCorn
Long Beach


Joined: 08 Jan 2011
Posts: 6951
Location: Nottingham, England

2004 Porsche 996 Turbo

PostPosted: Tue Feb 12, 2019 7:48 am    Post subject: Reply with quote

MaxA wrote:
Correct me if I'm wrong, but I thought that for the 9971, you need a larger throttle body, a revised intake plenum and a custom remap in order to add power. And you'll do 'before', 'during' and 'after' runs on a decent dyno to (i) set a baseline, (ii) optimise the remap, and (ii) verify the gains. Dont know


Surely you would need to optimise the map with the original setup before you start. If a remap might give you 35hp with standard hardware, so you change the throttle body and plenum, then remap and find you have 25hp over base, you are still 10hp down from what you could have had. Certainly not easy to set up and test.

MC
 
  
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Thefinn
Suzuka


Joined: 11 Jun 2014
Posts: 1038
Location: Essex


PostPosted: Tue Feb 12, 2019 9:12 am    Post subject: Reply with quote

Yeah

wouldn't you have to custom map the car every time you changed / modded to see if gave gains and then map again with a combination of every mod to see if the combination gave better gains again over the stock items which would also need testing i.e. TB, then TB + headers, then TB + headers + Cats, Then TB + Headers + Cats + induction kit. All in you would have to map the car many many times with every variation (stock and aftermarket) to see which gave the best results so it would take days and cost a fortune unless you have a tuner that had the equipment to trial this and was actually interested in finding out for themselves.

edit: i have just hit a 1000 posts not quite at Phil and Alex's level but still a milestone
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MaxA
Barcelona


Joined: 11 Oct 2015
Posts: 1499
Location: Helsinki


PostPosted: Tue Feb 12, 2019 9:24 am    Post subject: Reply with quote

MisterCorn wrote:
MaxA wrote:
Correct me if I'm wrong, but I thought that for the 9971, you need a larger throttle body, a revised intake plenum and a custom remap in order to add power. And you'll do 'before', 'during' and 'after' runs on a decent dyno to (i) set a baseline, (ii) optimise the remap, and (ii) verify the gains. Dont know


Surely you would need to optimise the map with the original setup before you start. If a remap might give you 35hp with standard hardware, so you change the throttle body and plenum, then remap and find you have 25hp over base, you are still 10hp down from what you could have had. Certainly not easy to set up and test.

MC


I don't think a remap will add much by itself to an NA engine, hence people add the supporting mods and then get a remap. I would have thought that once you have set a baseline, you can test your gains/losses against that. I don't think the mods by themselves will add much. In my (limited) experience, some ECUs can adjust to cope with mods and power can be increased without a new map, but those tend to be forced induction.
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MaxA
Barcelona


Joined: 11 Oct 2015
Posts: 1499
Location: Helsinki


PostPosted: Tue Feb 12, 2019 9:35 am    Post subject: Reply with quote

Thefinn wrote:
Yeah

wouldn't you have to custom map the car every time you changed / modded to see if gave gains and then map again with a combination of every mod to see if the combination gave better gains again over the stock items which would also need testing i.e. TB, then TB + headers, then TB + headers + Cats, Then TB + Headers + Cats + induction kit. All in you would have to map the car many many times with every variation (stock and aftermarket) to see which gave the best results so it would take days and cost a fortune unless you have a tuner that had the equipment to trial this and was actually interested in finding out for themselves.



I suppose you're right. If you want to have an internet war, then you'll need a lot of dyno run graphs to sustain your arguments for the before and afters. And then it'll degenerate into a proxy war about which dyno, what software it was running, what transmission losses are acceptable (15%?), the ambient conditions, was the bonnet up, did you run a fan etc.

I simply don't know what to think about this post on FB. Maybe the throttle body really doesn't help, maybe it was freshly installed and the ECU hadn't adjusted for the second run, maybe there was no remap, maybe the second run was done on a stinking hot day without a fan. Who knows.

When I come to add the intake plenum to my 9972, I'll have my tuner do me a baseline run (or three, to give me an average), and then an afterwards (also average of three). It'll cost around half a day on the dyno, I suppose. And I'll try to be there, so I can see what's going on. And then I'll know what my car did on that day, in those conditions, on that dyno, with that fuel and those mods.
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ragpicker
Estoril


Joined: 14 Apr 2013
Posts: 3979
Location: North East England


PostPosted: Tue Feb 12, 2019 10:09 am    Post subject: Reply with quote

It certainly challenged my view.

Having spent quite a lot of time with Wayne and seen him demonstrate his craft first hand, including him teaching others, I'd be very surprised if he was wrong.
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Phil 997
Le Mans
Le Mans


Joined: 05 Dec 2015
Posts: 15190
Location: Bournemouth,Dorset

2009 Porsche 997 Carrera 4S

PostPosted: Tue Feb 12, 2019 10:38 am    Post subject: Reply with quote

MMMMMM very interesting , mainly due to the fact that it is actually Wayne from Chipwizards thats got my car to remap it.

I know that prior to the engine blowing it was dynode at 400 bhp with less mods than I have on it now and with a Regal remap . so thats 15bhp over stock plus a little for engine age.

When Porsche were developing the 997.2 they were after a bit more power than the previous model which is what they seem to do. interestingly one of those little things they changed on the gen2 was to go with a stock 82mm throttle body ,so if it was a bad idea and not worth doing why did Porsche do it Question I accept the DFI engine is a different beast but if the 82mm TB did nothing or infact reduced power why would Porsche use it. I have added the IPD plenum

Also theres the very plausible theory that Porsche use induction and exhaust as some of the ways to restrict the Carreras from getting to close to the performance of their flagship cars.

I was having a road race with a 997.1 GT3 in my 997.2 with the mods on it and was able to keep up with the GT3 his only advantage was that he could stay in the gear longer as they have a higher redline. and thats how he gradually pulled ahead of me as I kept hitting the red limiter and losing power.

I have great respect for Wayne at Chipwizards hence him being my mapper of choice after the rebuild, so it will be very very interesting to see what he gets out of my car , I am getting it set up with both the stock airbox with BMC filters and then the Fabspeed carbon twin cone performance induction . again to see what the difference is between the two .

Had this info come from anyone other than Wayne I would have dismissed it instantly, so it will be interesting to see what he has to say about my car and also the fact that I am after improvements on the power curve more than max BHP which is only bragging rights down the pub on a fast road car.

also theres this from Ken who is also highly respected in the Porsche world .worth a read .

https://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1101101&i=0


Reading this and other threads I do wonder if the facts get a bit confused eg. has someone tested a bigger throttle body but not changed the plenum , or has someone changed the throttle body and plenum but thought the car would re learn the values and when it didn't instead of getting a remap they moaned across the internet how disappointed they were.
I think we are aware there is a group of mods that include induction exhaust and maps that need to be done to see decent gains and if someone only does part of in the wrong order they may not see the gains another will see.

All I can say is I have changed a lot on both my gen1 and gen2 and feel gains but when Wayne has finished with my gen2 I will report back of whether his equipment says the same as my butt dyno Thumb Thumb Thumb
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Thefinn
Suzuka


Joined: 11 Jun 2014
Posts: 1038
Location: Essex


PostPosted: Tue Feb 12, 2019 10:38 am    Post subject: Reply with quote

ragpicker wrote:
It certainly challenged my view.

Having spent quite a lot of time with Wayne and seen him demonstrate his craft first hand, including him teaching others, I'd be very surprised if he was wrong.


Exactly do i now ditch my 82mm tb and stop perusing the induction kit i was just about to order Sad
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-- 997 --
Suzuka


Joined: 11 Jun 2015
Posts: 1178



PostPosted: Tue Feb 12, 2019 11:30 am    Post subject: Reply with quote

Mmmmmmm...... after reading this it has totally pushed me sideways to wanting the IPD Plenum and the 82mm GT3 TB upgrade OH also not forgetting the Fabspeed Carbon twin cone filter upgrade... these were my next mods on my list !!!!

Dilemma Confused

Untill i see some positive results on dynos with these mods it may straighten me for me to persue the mods but in the mean time i think ill order up a set of B6 for my Techart Lowering Springs...

J
 
  
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996ttalot
Approved Trader


Joined: 21 Sep 2009
Posts: 1450
Location: Horley Gatwick


PostPosted: Tue Feb 12, 2019 12:19 pm    Post subject: Reply with quote

Phil 997 wrote:
MMMMMM very interesting , mainly due to the fact that it is actually Wayne from Chipwizards thats got my car to remap it.

I know that prior to the engine blowing it was dynode at 400 bhp with less mods than I have on it now and with a Regal remap . so thats 15bhp over stock plus a little for engine age.

When Porsche were developing the 997.2 they were after a bit more power than the previous model which is what they seem to do. interestingly one of those little things they changed on the gen2 was to go with a stock 82mm throttle body ,so if it was a bad idea and not worth doing why did Porsche do it Question I accept the DFI engine is a different beast but if the 82mm TB did nothing or infact reduced power why would Porsche use it. I have added the IPD plenum

Also theres the very plausible theory that Porsche use induction and exhaust as some of the ways to restrict the Carreras from getting to close to the performance of their flagship cars.

I was having a road race with a 997.1 GT3 in my 997.2 with the mods on it and was able to keep up with the GT3 his only advantage was that he could stay in the gear longer as they have a higher redline. and thats how he gradually pulled ahead of me as I kept hitting the red limiter and losing power.

I have great respect for Wayne at Chipwizards hence him being my mapper of choice after the rebuild, so it will be very very interesting to see what he gets out of my car , I am getting it set up with both the stock airbox with BMC filters and then the Fabspeed carbon twin cone performance induction . again to see what the difference is between the two .

Had this info come from anyone other than Wayne I would have dismissed it instantly, so it will be interesting to see what he has to say about my car and also the fact that I am after improvements on the power curve more than max BHP which is only bragging rights down the pub on a fast road car.

also theres this from Ken who is also highly respected in the Porsche world .worth a read .

https://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1101101&i=0


Reading this and other threads I do wonder if the facts get a bit confused eg. has someone tested a bigger throttle body but not changed the plenum , or has someone changed the throttle body and plenum but thought the car would re learn the values and when it didn't instead of getting a remap they moaned across the internet how disappointed they were.
I think we are aware there is a group of mods that include induction exhaust and maps that need to be done to see decent gains and if someone only does part of in the wrong order they may not see the gains another will see.

All I can say is I have changed a lot on both my gen1 and gen2 and feel gains but when Wayne has finished with my gen2 I will report back of whether his equipment says the same as my butt dyno Thumb Thumb Thumb


I think the test you linked to was very controlled but importantly if you read through it states that the MAF was replaced on both cars to ensure it was reading 100%. You can have a MAF that is reading 10% down on actual flow without it triggering error messages. The bottom line was on the 997 car used, the air flow was up as showing in the tables from live data.

What I have seen is that sometimes mods that don't seem to show increase on dyno, do show power increase on the road over a specific performance measure e.g. 4th gear pull from 60-100mph using vbox data and the car is quicker using same conditions. It is why I don't use a dyno but real world airflow to the engine.

The maximum we see is 20whp increase approx from any na modifications in total (exhaust etc etc), but also we look for power under the curve.

Wayne and I are collaborating on a project in two weeks time so I'll have a chat and see if I can find out more. One car does not also make something right or wrong either.

Ken
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Phil 997
Le Mans
Le Mans


Joined: 05 Dec 2015
Posts: 15190
Location: Bournemouth,Dorset

2009 Porsche 997 Carrera 4S

PostPosted: Tue Feb 12, 2019 12:30 pm    Post subject: Reply with quote

Ken that makes a lot of sense , and would explain the butt dyno effect that isn't seen on a dyno. its a very interesting subject as these small mods with moderate gains are where most that like to play a bit are in.
Thumb Thumb It will be very interesting to follow your project . and I wouldn't disagree with your thoughts of around 20 whp for all the mods and would be more or less in line with my expectations along with a better power curve .Thumb
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MaxA
Barcelona


Joined: 11 Oct 2015
Posts: 1499
Location: Helsinki


PostPosted: Tue Feb 12, 2019 12:50 pm    Post subject: Reply with quote

I look forward to learning more from Ken at 9e and Wayne at ChipWizards. In the meantime, I would definitely agree that the benefits of a good package of mods and map are improved drivability and the whole 'area under the curve'. The days of just slapping on a bigger and better bit are long behind us, and usually just reveal weaknesses or restrictions elsewhere.
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Thefinn
Suzuka


Joined: 11 Jun 2014
Posts: 1038
Location: Essex


PostPosted: Tue Feb 12, 2019 1:23 pm    Post subject: Reply with quote

I really looking forward to finding out more about your progress on this Ken please keep us updated.

For us guys that like to mod their cars in the hope we can improve them but don't have the tools or knowledge to actually test them out in the real world, we are left picking through old post and the odd dyno chart while trying not to fall for the all of the over exaggerated advertised claims, so an actual tests and results from an expert would be a breath of fresh air, rather than the lottery we are normally faced with.


Pop Corn Pop Corn Pop Corn
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996ttalot
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PostPosted: Tue Feb 12, 2019 2:09 pm    Post subject: Reply with quote

Thefinn wrote:
I really looking forward to finding out more about your progress on this Ken please keep us updated.

For us guys that like to mod their cars in the hope we can improve them but don't have the tools or knowledge to actually test them out in the real world, we are left picking through old post and the odd dyno chart while trying not to fall for the all of the over exaggerated advertised claims, so an actual tests and results from an expert would be a breath of fresh air, rather than the lottery we are normally faced with.


Pop Corn Pop Corn Pop Corn
In our early days I can remember we thought that some aftermarket intercoolers were the business when tuning. Only until we got into real live datalogging did we find out otherwise. I ended up on four cars replacing those intercoolers with ones that worked foc.


The only way we put products onto a car for performance is if we can actually see a proper benefit on the road

Ken
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MisterCorn
Long Beach


Joined: 08 Jan 2011
Posts: 6951
Location: Nottingham, England

2004 Porsche 996 Turbo

PostPosted: Tue Feb 12, 2019 2:12 pm    Post subject: Reply with quote

Testing on the road has its own issues. I have some data showing a 20 degrees difference in intake temperature simply by turning the car around and going in the opposite direction. Don't test intercoolers on a windy day!!

MC
 
  
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NLW73
Barcelona


Joined: 27 May 2014
Posts: 1428
Location: Yateley


PostPosted: Wed Feb 13, 2019 11:13 am    Post subject: Reply with quote

Based on the post and the fact that Wayne is a legend when it comes to tuning NA cars then I am not going down that route and staying stock plenum and Tb

Was going to do the spyder route

I might go 200 cell cats for better flow and leave the car alone
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bazhart
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PostPosted: Wed Feb 13, 2019 2:09 pm    Post subject: Reply with quote

I have to agree with Wayne (he is brilliant) although sometimes it is very difficult to persuade other people to believe something they don't want to hear - to the point where it can not be worth trying (of which a choice of oils is a classic example).

It is so difficult to explain in a few words that I have been working on a comprehensive book on this subject due to be posted on our web site soon. One of the biggest stumbling blocks is that there has been over the last 40 years a general mistake made by almost everyone in understanding what makes a car accelerate fastest and so it is impossible to discuss the subject unless you can first explain the issues and then persuade readers to believe your own interpretation.

It is already over 30K words and 120 pages (including graphs, etc) and this is just because unless I cover all bases in my explanations - the forum will be full of never ending arguments that I don't have the time (or the inclination) to respond to.

Very briefly - tuning aids for a std capacity engines usually rely on shifting the power band upwards (at higher revs) and losing some mid range torque, often making the cars appear faster on paper (by quoting higher bhp figures and peak revs) but actually resulting in them being slower through the gears (due to the corresponding reduction in mid-range torque). This is because contrary to popular opinion, acceleration is proportional to rear wheel torque (not BHP) and rear wheel torque reduces in the same inverse proportion that the speed increases (or the gear ratio changes) so that as you change up through the gears the torque reduces.

Also you have to drive from the gears you start off at in each gear (after changing up) to peak revs and so the engine has to accelerate through a rev band in which the highest average torque will be fastest - but you can tweak the power curve to show more bhp at high revs but inevitably less average torque through the rev range.

The results often vary with the type of testing undertaken.


Bigger inlet throttle bodies are a classic example.


When carburettors were used the throttle had to have a venture to reduce air pressure (as the air speed increased) to life the fuel up from the float bowl to mix in the inlet - so the throttle body WAS A RESTRICTION and for racing (where low speed control and economy were not issues) would often benefit from larger inlets.


However fuel injectors do not need such a pressure drop so inlets can be designed without a reduced area. So - unless the throttle body is a restriction - fitting a larger one usually just does the same as a faster opening cam (wired throttles) because for the same foot movement on the throttle pedal the butterfly opens more and quicker - no different than if you were more aggressive on the pedal.

Similarly plenums and more open exhausts often fool the driver into thinking the car is faster when it isn't.

We have recently been working with a developer of new plenums who's own tests initially supported his design as more powerful but our tests didn't. after discussions between us - he has since agreed with ours under test conditions that are more similar to accelerating on the road and we are working together to try and find a genuine improvement.

Bigger inlets and/or exhausts result in it taking more time for the unsteady gas flow resulting from the engine speeding up and air flow rates varying - to settle down and so they may well flow more air if the test is conducted at fixed revs or slowly but be worse under fast accelerating conditions.


When dyno-testing customers cars, that have different inlet and/or exhaust systems, they are often (no usually) less powerful than the standard versions (Porsche knew what they were doing) but whatever state of tune your donor car is in - building an oversized engine eliminates these issues because it achieves both an increase in mid-range torque and BHP, better throttle response and acceleration (anywhere in the rev range) and results in a much easier car to drive fast without the need to rev it out all the time – reducing stress on mechanical parts and this is why we prefer this method of "tuning".

I am not saying you could not improve on Porsche's settings but you would probably need different cam timing and variocam settings to benefit from different inlet and exhaust systems.

Why this is possible is a big subject (and you will need a lot of experience and patience to follow our full technical explanations referred to previously when it is available) but the results are generally that with an oversized engine - the top end BHP increases in roughly proportion to the increase in capacity while the mid range torque usually increases even more than this (sometimes doubling that proportion in some areas).

The result is a general increase in mid range torque and BHP of around 15% to 17% and an increase in top end of 6% to 10%. Even when we convert cars that have been fitted with non-standard components (like noisy exhausts etc) where we often find them down on standard power to start with – the % increase after fitting the capacity conversions are almost identical.

As a result - we are reluctant to quote performance figures for our conversions because of these issues.

We are shortly posting a short report on our oversized engines on our web site that shows the test results from our engines and we have examples available for serious owners to test and see for themselves how much quicker they are (and the report in 911 and Porsche World confirmed this)

(a) We find that different cars of the same model often have slightly different output before we even start on the conversions.
(b) Different dyno-testing providers can end up with completely different results for the self same car.
(c) There are several different types of dyno-testing equipment (an engine dyno as used by Porsche, rolling road dyno’s, axle dyno’s and on board dyno’s).
(d) There are different methods of dyno testing (fixed rev points, dynamic, inertia).

For maximum acceleration you need to first decide what gears are most important for your ideal performance. On track it might be 3rd and 4th whereas on the road it might be 2nd to 3rd and for autobahn work may be 4th to 5th etc and the time it takes to go from the revs you start at when you change gear to peak revs is an issue because of unsteady gas flow influences and combustion temperatures resulting from different loads..

If you run a fast inertia run it will not compare with a slower one in which the dyno is loaded to accelerate slower.

An engine dyno also usually results in different load and speed factors and all of them are subject to adjusting formulas that can uplift any result.

All the above provide quite different shaped graphs and figures. Indeed if you trace the graphs in the manufacturer’s own handbooks over different 6 cylinder models and 20 years you will find that curves have become a simplified connection of straight lines and over the same period we have found that they have moved further away from those both we, Wayne and even the Porsche Club’s motorsport’s own designated test centre, find (while all 3 produce almost identical results to each other (ours being the same over 4K and very close to Wayne's under thos revs).

We are however happy to reveal before and after test results from our own cars – and customer rebuilt oversized engines.

So regardless of arguments about add ons - a Hartech oversized engine will provide improvements in both mid range and top end BHP and torque and therefore improves acceleration, driveability and all round performance far more impressively than most conventional tuning can achieve – and as a bonus – without over straining the engine and at a very modest cost if you are considering or need an engine rebuild anyway. However many other add-ons simply don't work or at least not as effectively as they are claimed to do.


Please don't bother to expect me to find time to answer disagreements on here right now - as this is what I have spent weeks writing the big article to achieve and it will do so when it is ready to post on our internet site.

After all this is just my take on things and others have their own - which is their right - but it might benefit you if you start working out who to trust.

Our Boxster and 996 engines despite being absolutely legal for racing have won the BRSCC championship, the Porsche Club Championship (and class 1 and 2) with excellent reliability. Wayne has similarly excelled in numerous tuning tasks for all sorts of models. You cannot achieve all this if you do not know what you are doing and furthermore you cannot cheat results if they end up winning races.

Baz
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You can trust us to "CARE FOR YOUR PORSCHE"
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