Jump to content
SAU Community

Recommended Posts

Right now i need a dump pipe to complete my exhaust system..

Are JJR dump pipe reliable... Anyone had any issues with theirs?? or should i save up for a jap one??

Are there much gain of gettin a full exhaust system??

Current exhaust system consist of

HKS hi Power Silent

de- cat

HPI front pipe

cheers

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/
Share on other sites

Right now i need a dump pipe to complete my exhaust system..

Are JJR dump pipe reliable... Anyone had any issues with theirs?? or should i save up for a jap one??

Are there much gain of gettin a full exhaust system??

Current exhaust system consist of

HKS hi Power Silent

de- cat

HPI front pipe

cheers

Ive had my jjr stainless bellmouth on 4 about a year now and no problems.Good upgrade over the stock item

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4528285
Share on other sites

Just a quick note with the JJR dumps, I purchased a full "hyperflow" i think its called and few years back. $899, dump & front (ALL IN ONE) and cat back. looks great, nice cannon design And the angle it sits is bloody awesome, fitment was really good overall was very very pleased with the bang for buck. note this system has no mufflers.

Only last year I chopped my dump (wanted a bend for my new dump i was fabricating) and i noticed where the split/divorce pipe that separates the waste flap gas away from turbine gas flow merges back in around 50cm down, where they had made the whole for it to flow back into down the dump, its 40mm pipe and the bloody hole was oval, jagged and around 32mm in diameter.

now i dont suppose this is the end of the world, considering it was on a small low mount setup. but i did have some creep issues. it would always go a few extra psi. i was at the track once and tried to set it to 12 psi but after the run the gauge recall said i had hit 16-17.

but the rest off the system is very good. sounds great fitted very well.

so just be aware if you buy a split dump

cheers

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4528306
Share on other sites

i have the bell mouth front/dump pipe on my 32gtst. i noticed a slight increase in torque. i had to cut the flange off and shorten the pipe by about 200mm then weld the flange back on, so just remember u may need to do the same thing. just a hot tip, spend 50bucks and heat wrap the pipe before you fit it. adam

Edited by adamskill
Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4528602
Share on other sites

I bought a bellmouth dump and was quite impressed with the quality. I went away from the split dump after hearing too many stories of wastegate creep caused by the split flange fouling on the wastegate and preventing it from opening properly. JJR have probably fixed that by now but I couldn't see the need for a split dump on a street car.

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4530314
Share on other sites

when you guys are talkin about it fowling the waste gate

do you mean

THIS ONE:

jjrscreamrb.jpg

OR THIS ONE:

jjrrbdump.jpg

OR THIS ONE:

jjrsplitdumprb.jpg

Cause im after just a split dump pipe so i can get some better exhaust flowage. (or all) and for my power range i dont think i need a full 3" removing the wastegate gasses from the stock 2.5" piping should free up enough flow as im only finding loss in power just before redline, however still sustaining maximum torque ;)

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4539131
Share on other sites

oh this is where my question comes, I ordered from jjr a front pipe dump pipe 1 piece, this dosent have the spliter at the start of the dump pipe for the other outlet on the turbo, is this a problem? Why do some dumps have the splitter to separate the 2 outlets? what difference is it not having the splitter? will i have problems at just 12 pounds stock turbo setup?

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4539297
Share on other sites

I have this: (didn't use those gaskets though)

jjrrbdump.jpg

Bought it probably a year or so ago? Haven't had any problems with it so far... Though the wastegate return was a bit rough on the inside, if I had something handy I would have cleaned it up...

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4539427
Share on other sites

I have a JJR split front+dump ( the 3rd pic ), which I bought second hand.

Only issue I had was that the wastegate pipe, due to sticking out further towards the engine than a traditional bell mouth would, clashed a bit with.... something, I can't remember - I think the water line from the turbo. But it was no biggie - you just have to push it a bit.

In terms of bolting up to the turbo and cat, I had no problems. Well, I snapped half the bolts onto the turbo cause they were seized and its an absolute bitch to bolt back up (especially without ratcheting spanners) but no problem with the product :P

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4539787
Share on other sites

Isn't that the whole point of the bellmouth? The fact that it doesn't separate the gases like the split dump does?

On my GT-RS turbo the exhaust umm.. part that bolts to the dump pipe had a built in separator whereas the stock turbo didn't, so the separator attachment on my split dump had to be removed when the new turbo went on. Hope that made sense.. So I imagine you would need a separator attachment made up for your dump pipe if you actually want to make use of the split design.

Edited by bryno
Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4539985
Share on other sites

was covered in great detail in a thread I read a while back.. something about turbulence and using a split dump to allow the gases to merge further down the pipe to create less turbulence/better flow.. think bellmouth allows you to go higher boost as the waste gate size isn't restricted like it is in the split design..

Some one who actually knows about this stuff would be better at answering that question though..

edit: found a bit of info on the split design.. gives you a bit of an idea, may not be entirely accurate though..

"Dual pipe technology is recognised by the major turbo company engineers to be the best way to make internally gated turbo's work in a most efficient way by breaking up (seperating) the different pressure ratio's between turbo and waste gas in order to eliminate turbulence. Eliminating all turbulance allows the turbo gas to rapidly accelerate away from the turbo. This action in turn reduces spool up time - produces more torque faster and will give a fatter torque curve all through the rev range."

Edited by bryno
Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4540036
Share on other sites

Ok but wat is used for what? Like if 1 big pipe is best why do they make split pipes? Or vice versa?

Do some searching, at higher levels of gas flow most splits have proven to be a restriction, and also a large number of wastegate flaps foul on the seperaters.... i would reccomend saving changing at some point, and getting a bellmouth, you could probably sell your HPI front pipe for the price of a JJR stainless bellmouth :blink:

Link to comment
https://www.sau.com.au/forums/topic/265039-jjr-dump-pipes/#findComment-4540271
Share on other sites

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

    • Very decent bit of kit. Definitely black it out I reckon.  
    • Because people who want that are buying euros. The people with the money to buy the aftermarket heads and blocks aren’t interested in efficiency or making -7 power, they’re making well over 1,000hp and pretty much only drive them at full throttle  best way to way make money is know your customer base and what they want and don’t spend money making things they don’t want. 
    • It's not, but it does feel like a bit of a missed opportunity regardless. For example, what if the cylinder head was redesigned to fit a GDI fuel system? It's worth like two full points of compression ratio when looking at modern GDI turbo vs PFI turbo. I'm pretty reliably surprised at how much less turbo it takes to make similar power out of a modern engine vs something like an RB26. Something with roughly the same dimensions as a -7 on an S55 is making absolutely silly power numbers compared to an RB26. I know there's a ton of power loss from things like high tension rings, high viscosity oil, clutch fan, AWD standby loss, etc but it's something like 700 whp in an F80 M3 vs 400 whp in an R33 GTR. The stock TF035HL4W turbos in an F80 M3 are really rather dinky little things and that's enough to get 400 whp at 18 psi. This just seems unwise no? I thought the general approach is if you aren't knock limited the MFB50 should be held constant through the RPM range. So more timing with RPM, but less timing with more cylinder filling. A VE-based table should accordingly inverse the VE curve of the engine.
    • I've seen tunes from big name workshops with cars making in excess of 700kW and one thing that stood out to me, is that noone is bothering with torque management. Everyone is throwing in as much timing as the motor can take for a pull. Sure that yields pretty numbers on a dyno, but it's not keeping these motors together for more than a few squirts down the straight without blowing coolant or head gaskets. If tuners, paid a bit more attention and took timing out in the mid range, managed boost a bit better, you'll probably see less motors grenading. Not to name names, or anything like that, but I've seen a tune, from a pretty wild GT-R from a big name tuner and I was but perplexed on the amount of timing jammed into it. You would have expected a quite a bit less timing at peak torque versus near the limiter, but there was literally 3 degrees of difference. Sure you want to make as much as possible throughout the RPM range, but why? At the expense of blowing motors? Anyhow I think we've gone off topic enough once again lol.
    • Because that’s not what any of them are building these heads or blocks for. It’s to hold over over 1000hp at the wheels without breaking and none of that stuff is required to make power 
×
×
  • Create New...