GN1 DP and waste gate. Who has one????

RED LS1

SENIOR MEMBER
Joined
Dec 31, 2001
I'm thinking of pulling the trigger on one of these units. It will be the 3 inch with the built in 46mm wastegate.

From the searching I did it seemed like no one had any real issues with the no name brand Wastegate. Thats a good start. Any reported issues I didnt find?

I have there 3 inch non WG unit right now and it fits real nice. No real modifing to speak of. Searching revealed that the WG model one needs modifing near the frame area. Is this true? Or do some just fit better than others?

Thanks in advance
 
Just put one on 2 weeks ago.

Nice piece.

The day after I put it on, my Powermaster took a sh!t, so I have not driven the car much.
 
How did it fit? Was there any clearance problems? I don't ming the lip under the heater box but I dont want to cut out the inner fender or frame.
 
It's a Turbonetics CPT 66. Probably do 20psi for street and 25-26 once in a while. Ported heads, 212 cam, 3200 stall, 25 Row intercooler, 60's and XFI.
 
I sell them and use one on my GN, the reason you have to trim the fenderwell is that these downpipes are designed to be used with ATR/Kenne Bell type headers that have the crossover that comes up into the motor compartment.
 
So your saying the Fender well must be modified and cut for this down pipe?? Thats a Red light for me.
 
Red light is on then. Not really a big deal to trim it. I have seen some guys run them without trimming but it is almost right against the plastic if you don't
 
Mine has been on for 4 years now. No trimming and fit great. I had it Jet Hot coated 2 years ago and its a nice piece. My inner fender doesnt show any real bad signs of melting either.

Coach
 
Damn. Mixed reviews. I took a further look at the one on the car now. I didn't realize it is touching the inner fender right now (Havn't started the car yet.)

I may shy away from the chinese Wastegate and save for the T-netics or Precision one. I just wish someone else made a turn key down pipe like this one that fit and had a good wastegate on it.
 
I recently installed one and had all sorts of issues. I believe that my flange that bolts to the turbo had slightly warped causing the pipe to be pulled over towards the frame/firewall. The flange was not warped really bad, but a little at the top equals a big difference of where the pipe ends up near the bottom. I had to grind out the holes on my up pipe to turbo so I could clock the turbo a few degrees clockwise which moved the bottom of the pipe away from the frame/firewall once it was bolted to the turbo. Even then when the test pipe was slid on, the bolt holes on the test pipe flange sat about 4-5 inches over(towards the passenger side) from where my cat back/exhaust bracket lined up. I was able to push it over with some effort and get the rest bolted up under the car, and I'm sure after a few heat cycles the pipe has probably accepted its new home and wont be a problem to re-install next time (if/when I need to remove it) Also the pipe sits so close to the inner fender that you really do have to trim the plastic. Its easy work with a Dremel with a saw blade attachment. Honestly, if I didn't have the resources or skill to do the modifications necessary to get the pipe to fit I would have called Mark (who I purchased it from) and started down the path of trying to exchange the pipe for another one. If I hadn't had the fitment issues I would have been really happy with the piece. Who knows... maybe I just got an "end of the day on friday" part.
 
I recently had a car with a stroker/67 combo with this dp and wastegate. Had problems with it over boosting whenever you stayed in the throttle more than a few seconds. Even with the spring removed the boost would still creep up to 25psi.. I cut it apart and found a few things that I didn't like. The wastegate valve was seizing up when heated and the pipe back into the dp wasn't opened up all the way.

I fabbed up a new Precision wastegate and the problems went away.


2011-09-03 14.16.39.jpg2011-09-11 19.52.44.jpg
 
i have a 3.5" with external gate and it sticks over by the fender well to much. it could have been 2"'s closer. i have ta race ss headers. this makes install tight. with the ta headers it is not bad because the headers dont have holes for the 3 bolt turbos they have slots so you have wiggle room. build quality and looks are great though.
 
just put one on 2 weeks ago.

Nice piece.

The day after i put it on, my powermaster took a sh!t, so i have not driven the car much.



stop your crying lol yep really nice down pipe works fine just got to trim little of your inner fender not much.
 
*Update*

I was really 50/50 on picking up this downpipe from GN1. But the fact is that for the cost and the fact that it's a true bolt on part with no fab required
(like buying a Turbonetics, Precision or Tial) It really kept me thinking.

I made the call to GN1. I discussed my concerns with the owner. He was very willing to take the time to talk out every inch of this downpipe from the fitment of pipe to the wastegate opperation. He is test fitting it for me, sugested a finish, and sending me extra 02 bungs with it. He took a lot of time to discuss the ups and downs of a lot of his parts and was honest and informative.

So far I was happy with the first pipe I recieved from him. (Non Wastegate that I havn't used yet)

Happy with the service

Hopefully happy with the new pipe coming.

GN1 = :cool:
 
Let me know how it works out for you. I got back under the car today and noticed that after driving it a bit the pipe is sitting really close to the frame. I'm not showing any knock retard on my scanmaster, but I'm worried it might show up when I crank the boost up. I'm only running 15 pounds right now and I'm planning on running 22-24 with alky... so the engine may torque quite a bit more.
 
I recently installed one and had all sorts of issues. I believe that my flange that bolts to the turbo had slightly warped causing the pipe to be pulled over towards the frame/firewall. The flange was not warped really bad, but a little at the top equals a big difference of where the pipe ends up near the bottom. I had to grind out the holes on my up pipe to turbo so I could clock the turbo a few degrees clockwise which moved the bottom of the pipe away from the frame/firewall once it was bolted to the turbo. Even then when the test pipe was slid on, the bolt holes on the test pipe flange sat about 4-5 inches over(towards the passenger side) from where my cat back/exhaust bracket lined up. I was able to push it over with some effort and get the rest bolted up under the car, and I'm sure after a few heat cycles the pipe has probably accepted its new home and wont be a problem to re-install next time (if/when I need to remove it) Also the pipe sits so close to the inner fender that you really do have to trim the plastic. Its easy work with a Dremel with a saw blade attachment. Honestly, if I didn't have the resources or skill to do the modifications necessary to get the pipe to fit I would have called Mark (who I purchased it from) and started down the path of trying to exchange the pipe for another one. If I hadn't had the fitment issues I would have been really happy with the piece. Who knows... maybe I just got an "end of the day on friday" part.

I have put on three of these pipes over the last couple of months. the first one I put on fit good and work good. the last two fit like crap, just like what was said here^.on the second one I put a car tie down on the drivers side frame and to the down pipe and bent it over to get it to work. the thrid one I sent it back because it was so bad and they did not like that much. they took a video of the pipe on a car trying to show me all the movement they had in it up and down, but I guess they thought I didnt know what the hell I was doing. in the movie when they unbolted the down pipe from the turbo they only had to bolts holding it on, well it moves alot that way. still had to strap it down and pull it over about 3inchs anyway I think the later pipes are not build very good.my 2 cents
 
I recently had a car with a stroker/67 combo with this dp and wastegate. Had problems with it over boosting whenever you stayed in the throttle more than a few seconds. Even with the spring removed the boost would still creep up to 25psi.. I cut it apart and found a few things that I didn't like. The wastegate valve was seizing up when heated and the pipe back into the dp wasn't opened up all the way.

I fabbed up a new Precision wastegate and the problems went away.


View attachment 143454View attachment 143455

Nice job Jason !!
I need my headers/wastegate setup like that. ( when I actually get a good set of headers... :) )

Bryan
 
Here is a preview of the pipe. It definetely looks good. In fairness I will not update with fitment results untill Get it bolted down for good. A lot of stuff in this motor compartment is not complete because the cars still going together from scratch so disregard any faults you see in the pictures. It's a work in progress.





1009111005a.jpg


1009111005.jpg





To be continued. ..
 
FYI......I had to trim all kinds of the fender liner out, enlarge the holes on the flange and the turbo to header mounting point just to get this pipe to stay off the frame. I've owned this car since new and its never been in an accident. All new motor, trans, and body mounts so I'm very confident there isn't an issue with my car. Trimming the body seam under the heater box was necessary as well. When I voiced my concern to the manufacturer I was told if I wanted to pay send it back to them so they could test fit it on their car I could, but if it fits their car then its not their problem.

Long story short, after modifying several points on my car, enlarging bolt holes and denting the pipe along the frame, it is useable....but you'd think that for $500 you could make something that bolts in.
 
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