Gn1 downpipe.

[Steve V]

Anyone had fitment issues like this? They say roll lip on firewall, cut inner fendar well. Still way out of alignment with exhaust 4 bolt flange. Car has H&R mounts.

 

[Phoneguy]

You are not the first...Mine fit like shit back in 2007, melted my fenderwell...

Good luck

Bryan

 

[Steve V]

Not my car, I would not run his pipe. RJC , real THDP or TA only..LOL... I know for sure it is the pipe not the car.

 

[Phoneguy]

Not my car, I would not run his pipe. RJC , real THDP or TA only..LOL... I know for sure it is the pipe not the car.

It is definitely the pipe....

 

[bison]

I have seen similar many times and I have seen issues with just about every manufacturer that sells pipes that are usually considered "bolt in". Doesn't line up, too close the fender well, hits heater box, puck location incorrect, swing valve location incorrect, swing valve shaft clearance too small, flange to pipe clocking incorrect, hole spacing incorrect, pipe hitting frame,etc. Sometimes 2 or 3 of these issues with one pipe. People ask me how much for a pipe from the fab shop and are often shocked when I say $1200-1400. The $1200 pipe fits perfectly and won't have any of the issues I mentioned. I've seen internal gated pipes slow cars down half a second because of poor puck alignment or failure to sit flush on the ex housing. Most would be better off with the stock elbow and dp. It works every time, has good puck location, never seizes, and clears everything. I've never seen a cheap one piece pipe work properly every time. Always need to do some tweaking


BPE2013@hotmail.com

 

[1952ray]

Delete

 

[Steve V]

I have seen similar many times and I have seen issues with just about every manufacturer that sells pipes that are usually considered "bolt in". Doesn't line up, too close the fender well, hits heater box, puck location incorrect, swing valve location incorrect, swing valve shaft clearance too small, flange to pipe clocking incorrect, hole spacing incorrect, pipe hitting frame,etc. Sometimes 2 or 3 of these issues with one pipe. People ask me how much for a pipe from the fab shop and are often shocked when I say $1200-1400. The $1200 pipe fits perfectly and won't have any of the issues I mentioned. I've seen internal gated pipes slow cars down half a second because of poor puck alignment or failure to sit flush on the ex housing. Most would be better off with the stock elbow and dp. It works every time, has good puck location, never seizes, and clears everything. I've never seen a cheap one piece pipe work properly every time. Always need to do some tweaking


BPE2013@hotmail.com

I understand that. I just have never seen one so far off on something I have worked on.

 

[Mike T]

The OP's pipe does appear to be way off and he has a legitimate complaint but it would only take maybe an 1/8 or 3/16 of misalignment somewhere in the turbine end of the pipe to cause this. I have been working on a couple of different pipe designs myself and have found that even if a pipe fits perfect on my car that doesn't mean it's going to fit the next car in the same way.

The 4 biggest factors that I have found that will determine if a pipe will fit or not (aside from just being a POS) are the type/condition of the motor mounts, type/condition of the body mounts, type/condition of the upper control arm and the passenger side header. Small distortions or twist in the header will have a subtle effect on the turbo angle and will be multiplied as you go farther down the pipe.

I like HR mounts to distance the motor from the frame, poly body mount to distance the body from the frame and not mandatory but tubular uppers also help create even more clearance.

Without removing the A/C this would create the biggest hole that I can think of for the downpipe to go through.

 

[Steve V]

The OP's pipe does appear to be way off and he has a legitimate complaint but it would only take maybe an 1/8 or 3/16 of misalignment somewhere in the turbine end of the pipe to cause this. I have been working on a couple of different pipe designs myself and have found that even if a pipe fits perfect on my car that doesn't mean it's going to fit the next car in the same way.

The 4 biggest factors that I have found that will determine if a pipe will fit or not (aside from just being a POS) are the type/condition of the motor mounts, type/condition of the body mounts, type/condition of the upper control arm and the passenger side header. Small distortions or twist in the header will have a subtle effect on the turbo angle and will be multiplied as you go farther down the pipe.

I like HR mounts to distance the motor from the frame, poly body mount to distance the body from the frame and not mandatory but tubular uppers also help create even more clearance.

Without removing the A/C this would create the biggest hole that I can think of for the downpipe to go through.

Agree and understood. Stock pass header, H&R mount, new stock UCA bushings not tubular. Body mounts are rubber. Raising the body would help the ac box issue, but not being too close to the frame. It is quite possible that pipe was off just a bit in the jig and hence the issue. I am letting the cars owner deal with Gn1. I can reinstall a stocker or his Kirban pipe for the time being.

 

[Mike Licht]

I would try loosening up the bolts that hold the turbo to the header or even slot the holes in the headers a bit to move, that usually works.. These cars can be off from one to another quite a bit. I have had pipes that fit perfect on one car and not close on another. All Brands even Terry houston

 

[Steve V]

Looks like Archie has viewed this thread. I received a phone call from the owner of the car saying he was pissed about this thread. Also saying I am not a real mechanic If I can't get it to fit. Archie says to loosen "some" bracket at the tranny and it will slide right over. Well I understand there's bad blood between GN1 and this forum. I am not trying to stir that pot. I have asked for opinions and received what I was looking for, "some" bracket" probably refers to the tranny mount. Yes I understand all cars are different etc.

 

[DavidM]

Well did you loosen "some" bracket at the tranny and did it fit? Lol
Maybe a BFH will knock it in place?

 

[Phoneguy]

Need a BFT ...

 

[huntsg]

Not that this will help with your fit, but I will say when I went to the ATR headers I bought a GN1 external wastegate down pipe and mine fit with no issues.

 

[psycho6cyl]

look on the pipe does it say made on a friday? that may be it. lol