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2.5T owners thread (please sticky)

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
So I've been getting a lot of PMs about running a boosted 2.5 and I've seen a few more people with em on here. Figured I'd start a thread for it so theres a good place to scroll through before posting up. First off I'd like to take a roll call and as questions pop up we can keep em all in the same place. Also heres some basics.

FAQ
1. Your powertrain warranty will be void though other parts of the may still be covered (personally have had a wheel bearing replaced under waranty).
2. Kit parts and parts destroyed by defective kit parts and poor installation do have some level of warranty its just slow and a big hassle
3. SPA, eurojet, c2, ATP all have t3 manifolds that they have made though I am unsure of the off the shelf availability on some of the mentioned applications... C2 has software for any project except 2009s and I believe unitronic can be of assistance as well.
4. Boost is managed off the wastegate on c2 kits and should remain that way unless you are dropping compression or running meth.
5. Most people have had things go very smoothly with the c2 kit though you should be prepared for problems
6. Stg 2 clutch and GTI brakes are recomended for stg 2 and above and I would also recomend a torque mount insert
7. Early c2 flashes had idle code issues in the tune which have since been resolved as have the emissions readiness
8. The c2 tunes seem to prefer oxygenated gas.
9. Have a 2nd car, we are talking about boosting an N/A engine after all and downtime can be longer than anticipated
10. Some 2.5T owners on the Tex have started a 2.5T forum http://www.germanmods.com/forum/
11. Other stuff I'd highly recommend when going turbo on a 2.5 are a Ross Tech VCDS, a south bend stg 3 clutch with single mass flywheel, Limited Slip Differential(especially on 07s that have notoriously weak diffs), Podi or other electronic boost gauge, and Air Fuel Gauge as well as oil pressure gague... AFR especially if you wanna start playing with boost levels with a meth kit.
 
Last edited:

dpham00

Modérateur Emeritus
Location
Los Angeles, CA

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
bump
 

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
made some adjustments as since doing the original post a couple years ago I've gained considerable knowledge and some of the info needed updating as more products have become available. I'll most likely be rereading over this over the weekend and fixing more information and coming up with more information. Sorry for the epic bump
 

anile_eight

Go Kart Champion
Location
Savannah, GA
I'm worried about reliability of the engine... How long at you had your kit on? Stage I or II?
 

darcness

Go Kart Champion
Location
Grand Blanc MI
Car(s)
2008 GTI CW
My buddy Shashi, who's name on here is Tbugsy has an AT turbo'd bunny done by C2. Not sure which Stage, but I think it's Stage 2. He's hot a lot of problems with the transmission since having the C2 kit installed. In fact last time I talked to him he said it was to the point that the car was almost undriveable due to the slippage of the trans.
 

anile_eight

Go Kart Champion
Location
Savannah, GA
In fact last time I talked to him he said it was to the point that the car was almost undriveable due to the slippage of the trans.

the clutch slipping on the flywheel or did he shred his gears?
 

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
I'll say trans issues are the only bothersome thing... engine wise I haven't heard any issues aside from one guy who decided to run 87 octane one day. I've been c2 stg 2 since August 2008 though my cars been down for a long time due to blowing my diff through the trans housing on my stock 5MT. Most of the AT cars have held up decent on stg 2 from what I understand. A clutch upgrade is a must on the 5MT and I'd highly advise an LSD to compensate for the notoriously weak diff on the 07 manuals. On my car I switched to the o2j 5MT from a 1.8T with a Quaife LSD and am running a southbend stg 3 clutch with single mass flywheel. I will also say that having a high quality boost gauge is a must.
 

anile_eight

Go Kart Champion
Location
Savannah, GA
^ That all makes sense! I have an 06, I haven't heard anything about those trans... are their diff just as bad as the 07?
 

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
the 07s in particular were the worst and had ring gear issues as well but the OA4s in general are one of the weaker VW transmissions. If you do blow up a factory trans swapping to an o2j from a 1.8T is very easy and only requires swapping over axle cups and shifter and making minor modifications to the linkage bracket. o2js are more affordable and have significantly better aftermarket support. I'd assume a g60 o2a could possibly work but I haven't personally tried that. I also know the o2m and o2q have been swapped on to 2.5s, I'm pretty sure the o2q from the GTI requires changing to GTI axles as well
 

anile_eight

Go Kart Champion
Location
Savannah, GA
I know catch cans are for turbo engines with direct injection but would it be needed on ours? Mine an 06' does not have direct injection but would it still be recommended? or how would that work, so we have the pvc at all? (I think)... A little confused on this one.
 

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
I'd actually advise running a catch can on a boosted 2.5, I'm not yet but its on the to do list. Wouldn't hurt anything on a NA 2.5 just isn't as important of a mod as on a boosted car. Definitely isn't as important as it is on a direct injected car. Phil from BSH was saying he really wanted to develop a catch can kit for the 2.5. One thing to keep in mind though is on the 2.5 the PCV is an integral part of the valve cover.
 

anile_eight

Go Kart Champion
Location
Savannah, GA
I was thinking about it being part of my purchase... Would a 2.0T catch can work, or would I have to make custom fittings to fit our pcv system?
 

John/Cue\Publik

Speed>stance
Location
Lake Stevens, WA
Car(s)
2007 Rabbit
you'd have to make up hoses for it the existing fitting for the pcv can be used
 
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