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420a Eclipse Downpipe

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Jeff99GS

15+ Year Contributor
1,870
17
Jun 27, 2006
Cleveland, Ohio
I need a downpipe for a t3/t4 420a eclipse......where can I find one? I serched on here and all I see is ones that have no turbo flange. they just have a small flange down low...is that for the 4g63??? Does anyone have a downpipe they want to sell?? I also need that small pice of pipe to go from my wastegate into my down pipe....where do you get a small peice of pipe like that???????? I have had trouble finding it:confused:
 
There is no one-size-fits-all downpipe for the 420A. I suggest you gather the appropriate flanges and having a local exhaust shop make a downpipe for you if you can't fabricate one yourself.

The stock exhaust size is 2.25"; 2.5"-3" pipes are a good idea, but useless unless you have a 2.5" or 3" exhaust and cat/test pipe to match it.

1.5" piping will suffice for most wastegate dump tubes.

You can buy pre-bent mandrel U-bends or J-bend on Jegs.com for a reasonable price. One U-bend should contain all of the necessary piping to make a decent downpipe. You can then weld it together yourself or cut it up and have a welder weld it together for you.
 
Jeff99GS said:
I need a downpipe for a t3/t4 420a eclipse......where can I find one? I serched on here and all I see is ones that have no turbo flange. they just have a small flange down low...is that for the 4g63??? Does anyone have a downpipe they want to sell?? I also need that small pice of pipe to go from my wastegate into my down pipe....where do you get a small peice of pipe like that???????? I have had trouble finding it:confused:

3 Bolt or 5 bolt flange on that t3.
 
Its a 5 bolt falnge...I have the flange and the flex pipe, I just dont have a welder, and I'm in OHIO the state of retarded hillbillys that dont know shit about turbo's....I just took it to a so called custom exhaust shop and they wont touch it :confused: they said they dont wanna break off a bolt in the turbo.

Can anyone tell me why I would get NO boost at all????? Is it the the wastgate or the boost controler
 
Jeff99GS said:
Its a 5 bolt falnge...I have the flange and the flex pipe, I just dont have a welder, and I'm in OHIO the state of retarded hillbillys that dont know shit about turbo's....I just took it to a so called custom exhaust shop and they wont touch it :confused: they said they dont wanna break off a bolt in the turbo.

Can anyone tell me why I would get NO boost at all????? Is it the the wastgate or the boost controler
It might be easier if you took it to an exhaust shop that had a bender. My dad used to make some downpipes for turbos. All you would have to do is bring in the flange and they have a machine in there that bends the pipe that they have. I don't see how this guy is saying he doesn't want to break a bolt off in the turbo? Is he planning on welding the downpipe together while its attached to the turbo? But he is obviously not to custom if he can't do it. You just have to find the right exhaust shop, alot of them don't have benders. All of the truly custom shops do though.
 
Jeff99GS said:
Its a 5 bolt falnge...I have the flange and the flex pipe, I just dont have a welder, and I'm in OHIO the state of retarded hillbillys that dont know shit about turbo's....I just took it to a so called custom exhaust shop and they wont touch it :confused: they said they dont wanna break off a bolt in the turbo.

Can anyone tell me why I would get NO boost at all????? Is it the the wastgate or the boost controler

For your downpipe, Why don't you prep a 5bolt flange, and explain to them how you want the flange welded on so that you can just install it yourself.

As for your boost problem, Its probably your wastegate. Assuming your external, you might want to check your gasket, and make sure all your bolts are tightened.
 
ok about the No boost thing...I have an external wastegate and its bolted to the manifold with a new gasket. I just have it venting to atmosphere and it seems like all my exhaust gasses are coming out of the opening on the wasgate. I think that my boost controler is all wrong :confused: It is some cheap ass bullshit....I put a port on my turbo outlet too for the manual boost controller to work properly and I still get no boost....Its all going out the wastegate
 
Here is a how to for your MBC.

http://www.dsmtuners.com/forums/showthread.php?t=105573


What is your boost supposed to be set at on the wastegate spring?
And make sure your boost gauge is sourced from the intake manifold and not the turbo.

The type of external gate that you have is supposed to dump to atmosphere right now, when the gate opens up thats when you you should here the exhaust gases coming out from there. (it should be a lot louder than normal driving)


Paul I couldn't find your diagram w/ the manual and electronic boost controller set up.
 
Unbolt the top portion of the wastegate... is there even a spring inside? That may be your problem.
 
Bah... that diagram in the link is really if you have a 4G63 or something. If possible, you should definitely try to source your wastegate boost line from the turbo's compressor housing.

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ok I'm looking in side the output side of the wastegate and the valve is all the way closed ....but exhaust gas is still coming throught there???? Is there supposed to be a ring in between the wastegate flange and the manifold flange that seats the wastegate valve??? I have some ring that I think should go in between there
 
the only problem Im having is it keeps blowing the hose conector off the end of the turbo....should I be using special clamps or will regular hose clamps work?
 
Jeff99GS said:
the only problem Im having is it keeps blowing the hose conector off the end of the turbo....should I be using special clamps or will regular hose clamps work?


T-bolt clamps are always a good idea, especially if you're already having problems keeping the pipes on. Another route is to have a bead rolled on the ends of the pipes, which just create a hump the coupler slides over and the clamp has to over come to pop off. Both T-bolt clamps and bead rolled pipes are a winning combination. :thumb:
 
yeah I have never had good results from JB weld, Its like duct tape for metal haha.. I just Cranked that clamp down and it stoped popin off!! Ok I have a few questions

1. I have a green and black spring in my wastegate....does anyone know what psi that is?the reason I ask is because no matter how much I turn up the boost controller it only boost to 5 psi which is okay for now but I just hope my gauge isnt crapy and its really at 20psi and ready to blow, the gauge is a Moohkee if thats how you spell it. is that crap?

2. should I put more oil in the car to compensate for the turbo? I doubt it but its worth askin.

3. should I use sinthetic oil or diffrent wieght oils?? or stick with the 5w30?

4. any recommendations on the spark plugs?? like cooler heat range plugs? I use NGK ...when i was running NOS, One stage colder plug? is that plug good for turbo aswell?

5. In this pic I circled where I drilled and tapped the turbo output for the boost control. Is that an okay location?





:dsm: :laser: 420a
 
1.
Small green spring= 7.252psi (0.500bar)
Large green spring = 13.053psi (0.900bar)

I have no idea what the black spring is... you're on your own finding that out.

2. A little more oil might be necessary to compensate - but not much. Just check your oil level after starting the car up and add accordingly.

3. 5W30 or 10W30 is what I always run. The turbo doesn't require synthetic, and it probably isn't worth spending the extra dough on unless you have a built bottom end or something.

4. NGK BPR7ES's (one range colder) are ideal if you're starting out boosting a lot: otherwise, the stock NGK BPR6ES will work fine too.

5. That boost source is in the perfect position.


By the way, that BOV is CF-tastic. :cool:
 
haha what you dont like that fake carbon fiber...Its does sound super though I love it!!!!

Oh yeah I just have One pretty big spring in the wastegate....its green but the bottom was black. It is probably just black from the heat. Id say its about 1" 1/2 round and 6" long
 
Oh... I thought you had two springs. The small green spring is 1.875in. (outside diameter), while the large green spring is 2.360in. (OD).

No 'filter' in the port...

I loathe CF.
 
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