Primary downpipes

[CHUPAPI]

Is anyone running primary and secondary catless downpipes ? Right now I have arc secondary and I was looking into getting primary. I have read about overboost issues and that the turbo won’t have enough back pressure and will leak oil. Does anyone know if this can be fixed with a tune and what are the performance gains?

 

[StingerRwd]

Hi, with a jb4 I had 15-21whp gain. Meth was in my car though. I can recall here in the forums that gains are about 30whp if you went full Carlee’s or just about what I’ve gained when I had jb4 meth. For me my boost issues where just spikes of 23psi and never had overboost. Others suffer from the overboost all the time going to limp mode. Just get the EWG wires or an EK1- JB4 BEF and you’ll not get the problem.
There is a thread here someone suggests 5w40 and that solves white smoke issues coming out the exhaust. In that same thread they also suggested a UPR check valve to reduce oil seepage more. I’ve seen 80 percent improvement in fueling smell and smoke when I had thicker oil and much better now when I’ve went with the BEF and now I’m straight piped with HFCs in the midpipe. If you don’t want the codes to pop up you can also purchase the

IMR 90 Degree 02 Sensor Cat for Tlx Type S, Stinger and G70​

 

[Striker's Stinger]

Hi, with a jb4 I had 15-21whp gain. Meth was in my car though. I can recall here in the forums that gains are about 30whp if you went full Carlee’s or just about what I’ve gained when I had jb4 meth. For me my boost issues where just spikes of 23psi and never had overboost. Others suffer from the overboost all the time going to limp mode. Just get the EWG wires or an EK1- JB4 BEF and you’ll not get the problem.
There is a thread here someone suggests 5w40 and that solves white smoke issues coming out the exhaust. In that same thread they also suggested a UPR check valve to reduce oil seepage more. I’ve seen 80 percent improvement in fueling smell and smoke when I had thicker oil and much better now when I’ve went with the BEF and now I’m straight piped with HFCs in the midpipe. If you don’t want the codes to pop up you can also purchase the

IMR 90 Degree 02 Sensor Cat for Tlx Type S, Stinger and G70​

Interesting even the NGT PDP on Lap3’s website says don’t run primaries and secondaries together.

“Please make sure to keep the secondary downpipes stock to prevent burning oil from OEM turbos not having enough backpressure.”

Was thinking about getting secondaries, but may be safer longevity wise to just stick with primaries?

 

[StingerRwd]

That’s a turbos thing back pressure which is normal across all cars. All turbo cars even BMWs. I recommend a muffler delete.

 

[Corleone1]

Here is mine.

Hmm, about backpressure... First, backpressure will kill a lot of power at higher revs so you don't won't it.
I don't agree that low backpressure cause oil leak. Backpressure is always there but less of course with better flow. Cause seems more to be overreving of turbos and by that it will be oil leak. We all need to tune boost curve for the

less backpressure and not to reach turbo overrev.