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Whatever you do dont get the dam JJR Split dump.

Iv just taken mine off. Had no end of trouble with boost creep issues.

1 being the wastegate catches on the inside,

2 after having that fixed, still no luck.. creep creep creep

So i ditched it. with the stock one, felt no difference, and holds steady 10psi with R32 actuator.

I think the problem is where it merges. The pressure from the main exhaust must be too high to allow the wastegate gasses to re-enter, therefore backing up or something. I mean there MUST be a problem with them, as as soon as i put the stock one back on, boom. Perfect. Am just going to match the stock dump to the HKS front pipe.

anyone else have some info on cats converters???????

i'll elaborate on the catco i got, it's the 5inch stainless one with flanges for a 3 inch system... it flows so much that last time my car was on a dyno there were flames :D

Whatever you do dont get the dam JJR Split dump.

Iv just taken mine off. Had no end of trouble with boost creep issues.

1 being the wastegate catches on the inside,

2 after having that fixed, still no luck.. creep creep creep

So i ditched it. with the stock one, felt no difference, and holds steady 10psi with R32 actuator.

I think the problem is where it merges. The pressure from the main exhaust must be too high to allow the wastegate gasses to re-enter, therefore backing up or something. I mean there MUST be a problem with them, as as soon as i put the stock one back on, boom. Perfect. Am just going to match the stock dump to the HKS front pipe.

for some reason (mainly price) people don't like hks, trust tomei dump pipes... i have the following exhaust setup and while it was not cheap, it has been rock solid...

hks split dump -> blitz front -> catco stainless cat -> fujitsubo power getter

all stainless not too loud, flows well, no creep and does not hang low to the ground...

Edited by Evil

my advice. forget the cheap copy split dumps. half of their 'benefits' are myth, and all too often the seperator fouls on the wastegate flap. plus you end up with 2 very small pipes. get the one big bell mouth dump. this allows the gas to rapidly expand as it comes out off the turbine which is exactly what you want to happen.

i'll elaborate on the catco i got, it's the 5inch stainless one with flanges for a 3 inch system... it flows so much that last time my car was on a dyno there were flames :D

for some reason (mainly price) people don't like hks, trust tomei dump pipes... i have the following exhaust setup and while it was not cheap, it has been rock solid...

hks split dump -> blitz front -> catco stainless cat -> fujitsubo power getter

all stainless not too loud, flows well, no creep and does not hang low to the ground...

Yeah the price puts alot of people off. I wont be getting an aftermarket dump pipe. Stock for stock turbo will be fine.

I dont mind spending money on good fitting quality products tho.

Mine is Stock Dump > HKS Front > Decat > HKS Silent Power. Sounds great!

i have the just jap split dump and the just jap hi flow cat.....great little mod and for the dollars its great......no problems at all altho im runnin standard boost and everythin.....so yeah.....a little extra flow is better...so for even better performance....take the guts out of the cat....lol.....but thats illegal so best not get caught if u do that.....

they seem to be good on stock turbos with standard boost but try go over that and the dreaded creep sets in. im just in the process of modding my split dump and turning it into a bell mouth (a bit of choppy choppy), hopefully this works out and i can finally control my boost :blink: , if not i,ll be pulling of my exhaust housing from my turbo and opening up the waste gate hole a little and a bit of internal cleaning up to get more flow through there as well.

well, chucked on my modded split dump(now bell mouth) and still doing to same thing, going to 17 psi at top rpm. thought it might be the bleed vale causing problems (starting to grab at straws) so took it off and plumbed hose straight from wastegate actuator to inlet pipe, still doing it although a bit slower. gunna try change the waste gate actuator with the one of my stock turbo, if that don't work, :huh: gunna pull off exhaust housing from turbo and open up the waste gate a bit

hey just a thought,

I think you should check what turbo the front pipes fits, I've got 1 before, got so preocupied with the performance cost material, etc that I forgot about the flange. I think the Justjaps ones fits only stock turbos

my advice. forget the cheap copy split dumps. half of their 'benefits' are myth, and all too often the seperator fouls on the wastegate flap. plus you end up with 2 very small pipes. get the one big bell mouth dump. this allows the gas to rapidly expand as it comes out off the turbine which is exactly what you want to happen.

this is what i was thinking when i initially put my china split dump on.

i put my mind at ease by putting two dump pipe gaskets to space it off a bit. works well and ive never had a boost problem. i dont have a boost controller (im running straight off the wastegate) and it runs 15psi straight to redline.

does anyone have a gt3076r iw?

What dump are you using? Anyone using a split? Photos?

Doing mine shortly and tuner has a quality split dump but the boost creep on other is getting me paranoid. So i dont have much faith that it will work well

what dump pipe is everyone out there running on there high flowed rb25 turbos, from what i remember the my exhaust housing was machined out to about 52mm(approx) to fit the new impeller. and was there wastegate modified ?????

Edited by Pal

dunno if anyone is reading this thread but im gunna chuck up my findings as i go anyway, checked out my actator and found out that it had been bent up and was making the waste gate not open fully (about 3/4 of the way open). re bent it to the correct length and boost has dropped down to about 14 to 15 psi instead of 17psi. looks like im goin to machine out the wastegate a little bit. done a test on a old exhaust housing and managed to go from the stock 25mm hole out to about 34mm, leaving about 1 to 1 1/2 mm of seating for the waste gate flap. hopefully that will fix my boost creep problem

i ended up buying the hks split dump.....

and what a difference, the quality shits all over the cheaper ones and i also noticed that the thickness is actually what they say... again not like the cheaper versions.

now im searching for a FRONT PIPE??????

anybody know where to get good quality ones in vic, i want to install them this weekend and dont have time to wait for international orders???

cheers

steve

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