Which Dump Pipe?

[Trozzle]

I can't remember what thread I bumped earlier about this, because forums appear to have reverted or something...

While replacing my stock turbo today with a hypergear ATR43G2 (which didn't happen, broke a manifold > turbo stud, and stripped another zzz) it has become apparent that my "full 3.5" exhaust" still retains the stock dump pipe. Since I wish to be flowing 270rwkw/18psi of exhaust gas through this, it's just not going to cut it.

I understand so far that I will be getting a bell mouth dump, but I cannot narrow down to WHAT dump, and from WHERE. There is a HPI stainless one on JustJap, but it's pushing $500 for the dump alone, and doesn't even say what size it is...I realise I need a 3.5" dump.

Can anyone please point me in the right direction as to what I'm after, and where I should get it from? I need is ASAP too, so I can't really afford to sniff around very much

I also looked through the RB25 upgrade thread, and not enough people mention their dump pipe, and certainly not enough people with the same power output I have in mind...

Thanks again for assistance guys

Edited August 21, 2010 by Trozzle

[bozodos]

get al el cheapo just jap bellmouth?

[wasnt me]

why do you need 3.5 inch? i think a 3inch dump and front pipes should do the trick for your power targets.

remember that as exhaust gas cools it expands. so the dump and front dont really need to be as big as the cat back back IMO.

[Trozzle]

cheapo 3" mild steel JJ you say? lol hmm ok

[Trozzle]

so JJR don't have just a 3" dump, only dump+front pipe. ZZZZZZZ

[RB25PWR]

I know I don't have anything positive to add but wtf is with ZZZZZZ? I see asians doing this all the fkn time in WoW. =\

[JonnoHR31]

get an exhaust shop to make one or do it yourself if your handy with a grinder and welder. i made myne up and tacked it together then got it welded properly at an exhaust shop

[PaulosECR33]

if you go just jap dont get a stainless one they are crap and the welds crack, even though you get a 12 month warranty its just not what you want to see after a month (personal experiance) i think they still sell a mild steel one

[Trozzle]

Don't have time...didn't expect this situation unfortunately so I'm a bit pressed to find something ASAP.

Also, zzzzzzz = snoring, duh.

I'll speak to tuner tomorrow morning straight up and see what he says...but looking back through more of the turbo results, enough people are getting more than I aim for with 3" dumps, so I'll probably get the JJR one straight up tomorrow morning.

[Trozzle]

Yes they sell a mild steel one for $20 cheaper, I'll just go with that then

[negativecamber]

is it the split type from just jap? dont get it as the hole for the exhaust is not big enough on the split style. i've just been through that with an ATR43. now changing to a v band type to solve the dump pipe probs.

[PaulosECR33]

i had the exact same problem with the split one, boost creep and shitty welds lol

[Randon_I_Am]

with this turbo setup the split one won't cause any interference with the gate opening... There's no possible chance the gate could hit hit dump

[negativecamber]

with this turbo setup the split one won't cause any interference with the gate opening... There's no possible chance the gate could hit hit dump

thats not the problem with this turbo and split dump, the problem is the size of the exhaust wheel size and the split dump pipe size. it wont be efficient like a bellmouth would. stock RB20/25 turbo's yes but not the ATR43. the ATR43 is probably the one of the biggest turbo you can have with the stock exhaust flange shape.

[hypergear]

Get the one with 3inch dump and front in one piece. I don't think any one makes an actual 3 inch dump pipe as the size of factory front pipe is in 2.5inches.

[zebra]

is it the split type from just jap? dont get it as the hole for the exhaust is not big enough on the split style. i've just been through that with an ATR43. now changing to a v band type to solve the dump pipe probs.

Did you even read the thread....clearly says at least 3 times that it is the bell-mouth one

[Trozzle]

Easy done. JJR 3" mild steel bell mouth dump+front pipe. Now let's hope there isn't any trouble bolting it to the more than likely f**ked cat. But that's the workshop's problem now

Edited August 21, 2010 by Trozzle

[CeJay]

I'd be careful running 18psi through a hi flow. Maybe it's irrational, but I blew my old high flow turbo at 17-18psi. Is yours bush or ball bearing?

[Hanaldo]

It's a hypergear turbo, it can take it

[discopotato03]

It sounds like minds are made up but just think about this for a second .

Outlet or dump pipes are bastard to get off the back of a turbocharger in situ and it is nice to be able to disconnect the exhaust from the bottom of the std dump and remove the turbo and cast dump pipe together .

Its much much easier to remove/refit a dump pipe on the bench and fit the complete assembly back on the exhaust manifold . Then simply re attach the front pipe to the dump pipe in the standard location . If the dump and front pipes are both 3" or whatever then its got to be better than std - and much easier to work on .

Imagine at a later stage you go to change a full exhaust and don't want to have to stuff around removing the one piece dump/front pipe from the turbo . Its a lot of fiddly work to do and the chance is always there of breaking studs or bolts off in the turbine housing which usually means turbo out to fix them .

My vote goes to a bell mouth with the joint in the factory location mainly because is a shitload easier to work on and if you break any fasteners their already apart and nuts and bolts (good ones) cheap and easy to replace .

Also importantly you MUST re use or replace any factory dump pipe braces because larger diameter exhausts are a LOT more rigid and put a lot more leverage into the turbo and exhaust manifold . RB engines are known for cracking exhaust manifolds particularly if the dump and turbo have to carry the weight of the exhaust system because some cork head removed all the factory hangers and didn't replace them .

I also thoroughly recommend you use some sort of "soft point" up the front of the exhaust so that the engine when it moves around doesn't put stresses into a more rigid exhaust system . Soft points can be those stainless concertina things with the outer braid or IMO preferably one of those spring loaded carbon ring swivel joints . These can be got through any exhaust place that gets the odd truck through because trucks use big ones and I've seen plenty with 3" exhausts or larger .

The swivel joints are a bonus because like flanged joints they are usually easy to get apart and separate exhaust sections .

The golden rule with exhausts is to do them properly and not have them act up later , set and forget .

Your calls , cheers A .