Yup. Passenger side top? And then you’ll suddenly move it one way and it will pop free. You’ll wonder if it will ever go back on, but it does.Working on my installation today....
I have gotten the Capristo Exhaust, Midpipe, and Intercooler hose removed, and all of the bolts for the shroud. However, I can't get the darn shroud removed. I have been wiggling, cajoling, and some minor forcing, but it resists being removed.. I removed the upper heat shield bolts for the fuel tank and it has given me more wiggle room, but there is some cooling pipe that is VERY VERY close to the shroud that is making removal very hard.
Is silver or grey an option? Like:What do you guys think of incognito ceramic coating? Black or white? Another step towards droping the engine bay temps that I'm thinking of for some time now. It just breaks my heart to have the exhaust components in its shine and rainbow look all covered by coating...
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Black, white, silver, grey, all available.Is silver or grey an option?
How effective are the ceramic coatings compared to wrap?
It is a felony, indeed. I guess I'll give it a try on my car and we'll see how it works out.It is a felony to hide those welds, but in my opinion, this is not a beauty contest, so if it works good, I think it should be an option. I would consider it strongly if there are data that proves function, when time comes for exhaust. And I like the trade off with slightly less low end, in return for a better top end, so a replacement seems highly interesting.
OEM turbo is squeezed(as is should be for a good setup). But when reducing back pressure, increases power, it means that turbo isn't really "out of breath", because we cannot get more than compressor will give. The turbine might choke the engine on hotside, but thats not the same, although it steals power. And when reducing exhaust pressure increase power, it means that at least a part of the choke, was not down to turbo itself.Regarding the top end, the 4C's stock turbo is running out of breath at higher rpm range, so replacing OEM restrictive exhaust with the free flowing exhaust, does help a lot by reducing the backpressure and therefore gaining top end power. Also on remaped ECU's there is a lot of turbo surge on stock exhaust as the turbo is pushing more air in, than the engine can flow at the low-mid range rpm and this effect is only heating the charge air and putting stress on turbo, so we don't want it. Again free flowing exhaust does help with this issue too, but we still had to decrease maximal boost on our tune in this low-mid range to further reduce the turbo surge. Porting the head would help with this and increase overall engine power but let's not get to much off the topic here.
If this flow map below is correct, 1.6Bar is perfect to get maximum mass out of the compressor:I am aware of turbo characteristic and terminology so I wanted to simplify things a bit to make it more understandable. Perhaps I simplified it a bit too much for those of you who are more knowledgeable regarding the turbos and the word "out of breath" wasn't the most appropriate. For us, mere mortals I'll try to make another simplified, but more precise explanation.
Two turbo related things are happening once we boost our 4C engine beyond OEM setup (1.5 bar):
At low-mid range rpm and increased boost we are experiencing compressor surge as the turbo cannot push as much air as we are requesting into the engine, so part of the air is now escaping back through the compressor. Less backpressure (free flow exhaust and head porting) or reduced boost are the solution. Smaller compressor would help but we would sacrifice top end then, so no.
If we can flow the same amount of air into the engine at less boost (less backpressure) we are lowering air temps allowing us to advance ignition timing, gaining hp, but even without any change to ignition timing, the power increase at high rpm is notable between OEM exhaust, GMS 200 cell cat and GMS decat. The only logical connection I see behind this, it could be a rather small housing (AR) of our stock turbo and therfore lots of backpressure, but the spool is quick. Of course this is just a guesstimate until someone makes proper measurements. However, 3" exhaust should be spot on for 350hp figures, so no need to worry about exhaust being the bottleneck and the temperature drop in the engine bay and around the turbo is noticeable, allowing more stable engine power.
In 20 minutes, you will not have completed a full driving cycle and the e-test parameters will still show "not ready". No code means not ready to decide if you get one or not!Well, I got 20 minutes to drive with the exhaust installed with the Stock ECU. "All" that is installed is the main turbo pipe, Cat, Midpipe, and the Akrapovic adapter. I do not have the GMS muffler, as the shop will be using the Akrapovic adapter to adapt to my Capristo Exhaust. I was able to reuse both of the O2 sensors, and so far, I haven't tripped the "Check Engine" light with the stock ECU. Fingers Crossed on that one! I have a Porsche Clube HPDE in 2 weeks, so I hope it keeps working "normally"
I took it VERY easy to drive to the race shop. I did get some smoking early on, as I assume the wrap needed to "cook" some. It is quite loud, and cold start is an "event". It is loud enough for my neighborhood, that I am very glad I have the Capristo valved exhaust to be adapted to the GMS exhaust. The Capristo is a 2.5" Exhaust, so it shouldn't provide much flow constraints.
It's the same family turbocharger map but there could be some differences so not exactly comparable. Turbo map is presenting optimal working range without any restrictions which we have (exhaust, head flow, etc.). It helps us select optimal turbo for our application (mostly on engine displacement), but entire VE (volumetric efficiency) depends on the engine components, not the turbo itself. VE with help of turbo will dictate then the power.If this flow map below is correct, 1.6Bar is perfect to get maximum mass out of the compressor:
Are you going higher than 1.6?
And what pressure do you have between cylinder head and turbine inlet, did you weld some ports so it can be measured? Say that there is 2Bar here when exhaust valve close, thats 2Bar that is fighting air coming in when inlet valves are opening. Too much pressure here, and we know that we have to back off. Obviously too much to discuss with a keyboard, but just trying to mention it for the common knowledge, and in case it has slipped from your attention
It can also be mentioned that boost pressure number is kind of overrated, what really matters is the weight of new fresh air coming in. For example, with a supercharger, changing a cam result in lower boost, but still increase power output. Most would assume that reduced pressure = less power, but actually opposite result. I have close to no knowledge regarding cam, but I do not think we have adequate knowledge to be sure porting is the next logical step, maybe there are better options before this? As you kind of say, everything affects everything, and I feel that we only have scratched the surface for now...