I would like to purchase an uppipe and I was wondering if anyone could tell me if any of the brands put out more power than the others? I read that the turbo xs has a diamiter of 45mm (Helix57mm,Vishnu?,PDE50mm,Perrin? andAutospeed50mm)which is the best because it is the same diamiter as the turbo inlet. Is bigger better or is less turbulent better? I also heard that the turbo xs is better because it is made of cast iron which has better heat retention. Does anyone know the diamiter of the Perrin and the Vishnu? One last question. Is it hard to install factory heat shield to aftermarket uppipe? If so will some be harder than others and which one? Helix claims 15 whp gain and Vishnu claims 10 whp gain but none of the others make a claim. Thanks.


Joe

 

I would recomend Vishnu, designed for optimal flow, velocity and very tight tollerances. Quality is supurb.

Turbo XS the tollerances are very slack. I have seen the bolt pattern being rotated so far the bolt hole is almost breaking out of the side of the flange and the ports and gaskets mismatch up to 3/8 inch.

 

as long as it doesnt leak there will be almost no difference, judging by all the stuff I've read.

 

Iono, I think the best bang for your $$ is the Helix Flex up. Why? Because it flexes like your stock one. Cheaper too.

And an uppipe an an uppipe, just as long as it get rid of that damn cat before the turbo. Any one will do. Even the Gruppe-S uppipe if you want to save some $$.

The only thing that vishnu has is that stronger steel, but the flex to me in my opinion is a lot better long term. The flex relieves expansion and contraction that the heat gives off, and it compensates for the rattling of the engine. Giving the flanges and gaskets less tension, therefore less leaks.

 

I would suggest ours ( S-Squared ). It runs $225

Its a flex unit, but the best feature of ours is that you will not recieve a check engine light unlike the rest. Our EGT probe is installed the exact depth as the OEM unit and will function properly without the need of a resistor inline as a CEL fix.

our webpage is being redone and should be back up and running shortly, but if you are interested, email me.

 

why would you want to retain your stock egt probe in the uppipe? With a catless uppipe you're asking for trouble leaving it in. Plug that hole with a bolt and do the resistor fix IMHO.

San

 

we have never had 1 problem with the stock EGT remaining in the up-pipe.

what problems do you think will happen with the EGT probe remaining ?

 

i suggest helix

no cel either

 

says a catless uppipe will eventually cause the stock egt probe to break due to the increased heat and possibly injest itself into the turbo/engine. I for one ditched it as it's purpose is limited at best. No offense to your product intended.


http://forums.nasioc.com/forums/show...ght=uppipe+egt

http://forums.nasioc.com/forums/show...ght=uppipe+egt

http://forums.nasioc.com/forums/show...ght=uppipe+egt

San

 

our prototype uppipe has been in a car for almost 2 1/2 years now with no problems. Never threw an EGT and the stock probe is fine. I guess were lucky

as for the increase in EGTs, its been shown that by ditching the up-pipe cat, your EGTs actually decrease compaired to what they were before. If the stock EGT probe cannot handle a lower EGT temp then what it was stock, then there is a real problem.

as for the EGT probe only being used to detect if the cat has failed. It should throw an CEL if its used in an uppipe that has no cat, but it does not.

The ECU uses that probe for a lot more ( like actually monitoring the EGTs of the car to make sure they are at a safe level ) then just checking the cat for efficency.

 

That is true and can happen as the probe is somewhat protected by the CAT not that that makes a great deal of sense it happens non the less, the most problems we see from putting the probe back in have been caused by sloppy installation where the probe has been damaged somehow thus leading to it falling apart later on.

I would say the best uppipe for the buck is the Helix which also contains a properly located EGT bung and has never caused a CEL on a car when installed correctly (we have installed well over 50 of them) The Perrin unit also fits flawlessly and is a extremely well made piece.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com

 

proof the ECU does anything more with the uppipe EGT, I'm sure everyone would like to know. And if so, how come so many are running big hp applications without problems? I've had two aftermarket probe failures in my uppipe. I'm hoping they're in the bottom of my manifold. There's a lot of luck out there.

San

 

The EGT sensor in the uppipe is used to detect when EGT's get so high that it might damage the CAT thus causing the car to throw a CEL and run in limp mode to protect itself, the CEL thrown when the EGT sensor is removed is just that a CEL telling you the EGT sensor has failed.

The reason there is no CEL from a catless uppipe is because it never reads anywhere near the temp it would need to throw the CEL for the high temps with the cat not in there.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com

 

The ecu has 2 maps programmed for fuel ( hi det and low det ).

the ecu can determine detination between the knock sensor,O2 and the EGT temperature ( after 5.5kRPM the knock sensor us useless due to engine noise so the ecu will use the egt temperature and O2 to check for safety )

its just as easy to get away with running a 2.2k resistor for a fix since by that time, majority of people are not running the factory map in the ECU or using a piggyback. Its easy to get away with it since the stock.

we use the factory EGT in our uppipes as the solution to the CEL. We have not found a reason yet in our tests that require us to remove the EGT due to failure yet. It may happen someday, so I can never say never

I figure if an EGT probe is going to fail, it might be the one I have 6in away from #3 tapped into the manafold and not the stock one

 

Not sure how the ECU can read Det from either the front O2 or the EGT sensor that plain does not make sense, I always thought that it's switching method between the two maps was done prior to the 5.5k knock sensor cut off, thus using the stock knock sensor to derive knock and how it handles it. After all you can have way safe EGT's and still be detonating as well as way rich AFR and still be detonating so either as a switching method seems a little silly.

The only failed EGT sensors we have experienced have been damaged during installation/removal.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com