Jump to content
SAU Community

Recommended Posts

In summary, if I end up down on power I'll certainly be looking towards all the other potential issues before I go blaming the turbo for it. Stao warned me that my desire to stay legal looking can rob me of power, I'm prepared to accept this as the logic is sound. The only reason you won't see it happening with a 3076 is that >300rwkw these turbos are nowhere near their limits where your supporting mods really start to matter, but even then this forum is littered with people who have power problems and are running Garrett setups.

Someone back me up please.

See my tl;dr above, lol. What you wrote was a good explanation of what happens when you run a split dump. He's probably making more boost in his dump pipe than the intake manifold!

My return flow is performing so far. I also have cooler piping from turbo is 2inch then near the cooler it opens to 3inch. Then from the cooler it drops from 3inch to 2.5inch to the throttle body.

This car goes against the norm

A tad on/off topic

I was wondering with my bell mouth dump.

It has pretty dodgy welding as in really rough inside of the dump itself where they have modified it to be a bell mouth.

Would it be worth it to get a grinder or something similar and get rid of the little pointy bits of welding?

A tad on/off topic

I was wondering with my bell mouth dump.

It has pretty dodgy welding as in really rough inside of the dump itself where they have modified it to be a bell mouth.

Would it be worth it to get a grinder or something similar and get rid of the little pointy bits of welding?

Hold the gasket to it and see how intrusive it is beyond the gasket. If its massive build up then maybe, but its not going to effect the performance in the reality of the matter.

The logic & experiences of the split dump pipe being a restriction makes sense to me explained in that way. Thanks GTSTScott, Rolls and Birds for the explanation.

In any case buying one of these is not a hugely expensive gamble for me, so I will just have to wait a while, get one & sell the current one, and see how it goes.

Because retuning is fairly expensive though, I may want to make more changes than just the dump pipe to make more sure of getting more power. Finding out the dump didn't work & that it is indeed the FMIC after another retune would be a bit painful.

Another point to note; when I was speaking with Tao, and he asked what intercooler I have, he was of the opinion that even having a FMIC running the normal path (not turnflow), the only coolers he had seen consistently perform were Plazmaman ones and PWR (which he has on the test car). I asked about Blitz turnflows and he does not think these are reliable either, and definitely not anything JJR.

Hold the gasket to it and see how intrusive it is beyond the gasket. If its massive build up then maybe, but its not going to effect the performance in the reality of the matter.

Its inside the dump not on the outside.

Where the gasket sits it is perfectly flush.

I was just thinking with the air flowing down the exhaust and hitting bits of welding

Might post a photo up once I get home I think it will explain better

Its inside the dump not on the outside.

Where the gasket sits it is perfectly flush.

I was just thinking with the air flowing down the exhaust and hitting bits of welding

Might post a photo up once I get home I think it will explain better

I think he means hold the gasket to the flange and look inside the dump. If any of the lumps can be seen sticking out beyond the gasket then they may be worth grinding off.

I wont go into too much detail re the cooler, but its been documented elsewhere that they suck when trying to reach 300rwkw.

And your making such a noob assumption on the dump pipe, the split dumps normally cause boost control issues when the wastegate flapper fouls on the divider or flange itself. I dont know how else to describe it to you.. The back of the G3 turbo is completely open. It has an odd jellybean shaped outlet identical to the OEM dump pattern. You are using a split dump without the divider, because obviously the divider doesnt fit. Unbolt your dump and you will see the problem, the gas comes out of the back of the turbo and more or less hits a wall, except for the small round holes for the dump and wastegate tubes.

Dump pipes 101 is that the exhaust gas EXPANDS extremely rapidly as soon as it exits the back of the turbo. This is why there are good gains to be had in running 3.5-4" dumps even if your system is only 3".

That being said, the gas comes out the back of your turbo, into the empty area in the flange plate (and is trying its best to expand right about now) and then it has to find its way through little exhaust tubes that have a flat solid face around them. There is nothing directing the gas flow into that part of the pipe, some of the gas luckily will go straight into the tube and the rest will crash against the flat surface of the dump flange. That then pressurizes the area and the gas will forcibly find its way down the dump tube.

I think thats your main problem. The flat surface concept applies to the turnflow cooler also, they just arent aerodynamic enough for what they are IMHO.

Someone back me up please.

+1

look at the pics and you can clearly see the restrictions in the split dumps.

split:

rb25dumppipe.jpg

bell mount:

jjrmilddumpfrontrb-02.jpg

A tad on/off topic

I was wondering with my bell mouth dump.

It has pretty dodgy welding as in really rough inside of the dump itself where they have modified it to be a bell mouth.

Would it be worth it to get a grinder or something similar and get rid of the little pointy bits of welding?

Yes, clean up the dodgey welds like the 1st pic i posted above

A tad on/off topic

I was wondering with my bell mouth dump.

It has pretty dodgy welding as in really rough inside of the dump itself where they have modified it to be a bell mouth.

Would it be worth it to get a grinder or something similar and get rid of the little pointy bits of welding?

mine is exactly the same. i thought mine was out of shape as it has been overheated previously. im gonna attach it with a die grinder or maybe get it built up first then grind it back

Not worth bothering about IMO. I'm no expert on structural integrity, but I wouldn't think cleaning that up would be worth any sort of gain, so I wouldn't bother messing with the welds. If you do, make sure you remove your oxygen sensor!

How are people connecting their intercooler piping to their turbo? My stock one had right angle elbow that was bolted to the turbo

But the SS1PU doesn't have a spot to bolt me to my stock one to

Erm...

Samco-Sport-Silicone-Elbow-90-Degree-300x300.jpg

ermm.gif

The logic & experiences of the split dump pipe being a restriction makes sense to me explained in that way. Thanks GTSTScott, Rolls and Birds for the explanation.

In any case buying one of these is not a hugely expensive gamble for me, so I will just have to wait a while, get one & sell the current one, and see how it goes.

Because retuning is fairly expensive though, I may want to make more changes than just the dump pipe to make more sure of getting more power. Finding out the dump didn't work & that it is indeed the FMIC after another retune would be a bit painful.

Another point to note; when I was speaking with Tao, and he asked what intercooler I have, he was of the opinion that even having a FMIC running the normal path (not turnflow), the only coolers he had seen consistently perform were Plazmaman ones and PWR (which he has on the test car). I asked about Blitz turnflows and he does not think these are reliable either, and definitely not anything JJR.

Spend the $200 on the JJR bellmouth dump/front pipe.. change it yourself and you should notice right away a change in how the car feels, obviously dont go too nuts until you get a retune.. if you cant afford the $200 for a dump pipe sell the car before a coilpack lets go (im kidding) but seriously for the money they are a great bit of kit but your exhaust might sit a little lower if its anything like mine and need to be tucked up a bit at an exhaust shop.

I run a blitz turnflow cooler and have also lent it out for a few tunes and they handled 280rwkw on a rb25 just fine, my guess is that they are a better design than the JJR ones and do a better cooling job so therefore colder air = smaller area and more power from cooler intake charge.. Im still running a standard hypergear highflow and pumping out 250rwkw all day everyday at 16-17psi flat with 10:1 comp on BP98..

Will be seeing how this turbo goes on e85 before i consider either a GTX3071/3076 or go the way of a G3

How are people connecting their intercooler piping to their turbo? My stock one had right angle elbow that was bolted to the turbo

But the SS1PU doesn't have a spot to bolt me to my stock one to

or go to CGC/ebay and find a 'cast tight radius bend' in the required size.. weld that puppy on and you wont have to worry about possibly killing the silicone joiner (if you drive it like a maniac)

or go to CGC/ebay and find a 'cast tight radius bend' in the required size.. weld that puppy on and you wont have to worry about possibly killing the silicone joiner (if you drive it like a maniac)

With the silicon joined can I just tap my boost controller into the metal after it?

Not a huge problem having it 30cm from the turbo is it?

With the silicon joined can I just tap my boost controller into the metal after it?

Not a huge problem having it 30cm from the turbo is it?

That's where mine is, no problems at all thumbsup.gif

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • It would be well worth deciding where you want to go and what you care about. Reliability of everything in a 34 drops MASSIVELY above the 300kw mark. Keeping everything going great at beyond that value will cost ten times the $. Clutches become shit, gearboxes (and engines/bottom ends) become consumable, traction becomes crap. The good news is looking legalish/actually being legal is slighly under the 300kw mark. I would make the assumption you want to ditch the stock plenum too and want to go a front facing unit of some description due to the cross flow. Do the bends on a return flow hurt? Not really. A couple of bends do make a difference but not nearly as much in a forced induction situation. Add 1psi of boost to overcome it. Nobody has ever gone and done a track session monitoring IAT then done a different session on a different intercooler and monitored IAT to see the difference here. All of the benefits here are likely in the "My engine is a forged consumable that I drive once a year because it needs a rebuild every year which takes 9 months of the year to complete" territory. It would be well worth deciding where you want to go and what you care about with this car.
    • By "reverse flow", do you mean "return flow"? Being the IC having a return pipe back behind the bumper reo, or similar? If so... I am currently making ~250 rwkW on a Neo at ~17-18 psi. With a return flow. There's nothing to indicate that it is costing me a lot of power at this level, and I would be surprised if I could not push it harder. True, I have not measured pressure drop across it or IAT changes, but the car does not seem upset about it in any way. I won't be bothering to look into it unless it starts giving trouble or doesn't respond to boost increases when I next put it on the dyno. FWIW, it was tuned with the boost controller off, so achieving ~15-16 psi on the wastegate spring alone, and it is noticeably quicker with the boost controller on and yielding a couple of extra pounds. Hence why I think it is doing OK. So, no, I would not arbitrarily say that return flows are restrictive. Yes, they are certainly restrictive if you're aiming for higher power levels. But I also think that the happy place for a street car is <300 rwkW anyway, so I'm not going to be aiming for power levels that would require me to change the inlet pipework. My car looks very stock, even though everything is different. The turbo and inlet pipes all look stock and run in the stock locations, The airbox looks stock (apart from the inlet being opened up). The turbo looks stock, because it's in the stock location, is the stock housings and can't really be seen anyway. It makes enough power to be good to drive, but won't raise eyebrows if I ever f**k up enough for the cops to lift the bonnet.
    • There is a guy who said he can weld me piping without having to cut chassis, maybe I do that ? Or do I just go reverse flow but isn’t reverse flow very limited once again? 
    • I haven’t yet cut the chassis, maybe I switch to a reverse flow. I’ve got the Intercooler mounted as I already had it but not cut yet. Might have to speak to an engineer 
    • Yes that’s another issue, I always have a front mount, plus will be turbo plus intake will big hasstle. I’ve been told if it looks stock they’re fine with it by a couple others who have done it ahahaha.    I know @Kinkstaah said the stock gtt airbox is limiting but I might just have to do that to avoid a defect so it atleast looks legit. Or an enclosed pod so it’s hidden away and feed air from the snorkel and below Intercooler holes like kinstaah mentioned. Hmm what to do 
×
×
  • Create New...