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Hey guys,

Just installed my new JJR dump/front to my R34 and have a few issues niggling me which I hope to sort out asap:

  1. there is no centre bracket welded on the JJR dump/front and I made a make-do temporary hanger with 2 X metal hose clamps and a zip tie to chasis mount (see pic, zip tie wasn't in place then but it is zip tied to the second clamp off the exhaust pipe to prevent it melting lol. If you wondering why I didnt run the second clamp in through the hole in the chasis mount thats because the holes too small lol.. What can I do here, is it dangerous ti have the exhaust hanging off the turbo and the next hanger is way too far near the diff and mid muffler. Willl this stress my metal exhaust components?? Cant drive to exhaust shop, I'm suspended, but need a temp fix.
  2. I didn't install back the stock heatshield (for now), its a pain getting the dump bolts off with it and the brackets in place, just wanted it clean-cut. Under bonnet temps were noticeablly higher after a quick run in my side street. I've read posts where most pple recommend putting it back on, is this the go?? Dont wana fry my hoses and wires - see marked in red box, they are about 15-20cm off the exposed dump and turbo hot side, is this bad??
  3. Haven't put in my O2 sensor yet, read posts where it is mentioned that the two white wires doesn't matter in which way they need to be hooked up. Is this correct? See new sensor and existing plug - do I just go black-black and white-white X2, orientation of white wires dosent matter?
  4. Finally the car, after warming up on idle say 7-10mins and then driving a quick 5-7mins went a lot harder, boosting much quicker and much stronger (noticeable lag down low 2000rpms tho??), BUT after these 7 mins it spluttered a bit, engine and dash lights went on and it died. Started up fine but stuttering and idle was dying again so I quickly parked it away, I noticed a bit of smoke out the rear and briefly a rich fuel smell then. Is this the ECU sensing no O2 sensor and running very rich and retarded?? I think JEZ tuned it WITH the sensor on. Whats with the spluttering and died once? Tomorrow I'm putting my new sensor on, just need to be sure of the wire colors..

Thanks heap if some of yous could enlighten me.. :wacko:

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Edited by rondofj
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1: i drove my car round for as long as i owned it without it attached to that front bracket.

2: most people i know have run them without the heat shields after putting on an aftermarket exhaust

3: i can't remember, but most likely matching the colours will be fine

4: it was probably running a bit rich from lack of o2 sensor, but shouldn't have really affected the timing (so not rich and retard). more likely is that the coils are a bit weak and the extra airflow is putting stress on them. getting the o2 sensor sorted should help with that, but if the plugs are getting on a bit i'd replace them. if they aren't that old then i'd gap them down to 0.8mm (if they are the stock gap of 1.1mm) and see what that does.

1. I got a bracket welded onto mine, though you shouldn't have an issue without one if you're not tracking the car.

2. I don't run a heat shield, don't have any issues.

3. Not sure what you're trying to do there.

4. If you're running NIStune, the lack of an O2 sensor will have thrown up a code, which may have sent it into the knock maps. So if Jez has tuned the knock maps to be richer with less timing, then that would make sense. I know mine did not like to run with no O2 sensor before it was tuned out.

Side note - there shouldn't be any more lag, especially not 2000rpm. If anything it should be more responsive. That sounds like an exhaust leak to me.

Thanks for the replies fellows, really appreciate that, Hanaldo that noticeable lag at 2000 rpm is there for just half a second, after that it just lurches and i mean really lurches forward -instant 12psi on dial, very different than without dump, its really made that much difference. And part 3. of my post I meant that do I connect the new O2 sensor to old plug with black wire to black and two white wires on sensor to the two white wires on plug(heater wires??), does it matter which white goes to which as theres two?

Part 4 of post: And mad082, im running 0.8 gapped NGK coppers and yellow jackets just installed a few weeks back as well as Nistune, so the spluttering/ stalling a bit and engine/ ign lights on and engine shutting down Im hoping is O2 sensor related, will put it on tomorrow and test..

The exhaust bit is niggling me- no supports in the middle, just hanging off the turbo and the next immediate hanger out the back near rear diff, long unsupported section in middle- refreshing to know u didnt have issues with that..

Also the exposed turbo hot side not such a good idea i think as it will increase engine bay temps and hence intake temps??? Lets see what others say...

Also the exposed turbo hot side not such a good idea i think as it will increase engine bay temps and hence intake temps??? Lets see what others say...

It won't make much of a difference to your engine bay temps while you're driving, there's a lot of air moving around there to take the heat away. While stationary you will notice an increase, but it causes no problems.

What I did when I changed the exhaust on the r32 was modify the stock exhaust bracket,

It was 2.5inches semi circle so I got an angle grinder and cut the bracket in half so it was now only bolted to one side but that's better than no bracket at all

Ok guys so just put in my O2 sensor - (crimped and then taped wires with elec tape ok???) put the supplied heat cover on wire too. Goes n boosts quite hard, didnt shut down/ sputter/ throw engine light on like yesterday.. But it was only a 5 minute spin as i cant drive for now. Gotta wait for mate to come take it out for a run..

Btw my O2 sensor is only hand tight as i dont have a 22mm spanner/ tool, is that bad??? Leaks etc? Im assuming the heat from driving will seal it in anyway?

True, am goin to get me a large shifter, some heat wrap and a 13mm spanner/wrench from super crap auto.. That middle passenger side stud(out of 6) in the jjr dump onto turbo is impossible to fit any tool into, its also hand tight but the other five are ok.

That middle passenger side stud(out of 6) in the jjr dump

:laugh:

Seriously though, get that sorted. It's hard to get a tool on but it's not impossible. Leaving that bolt loose puts strain on the gasket, you'll end up blowing it. I suggest changing it to an inconel or high tensile/heat resistant allen key bolt, it's a LOT easier to get on and off.

I've been thinking about doing this, with the improvements that you say its made i think i've finally made my decision.

How was the fitment, straight bolt on? and what else do you need to buy to replace these, new gaskets? some sort of sealant? and did you keep the stock cat on it?

Agree dont keep stock cat, get a 3" straight thru cheap lobokka 100 cell metal cat off ebay (5" body).. Yes it was direct bolt on, i rocked up at just jap and the dude there gave me a packet of rubbish gaskets n nuts too so i just used the stock ones which were in great nick, no gasket goo, hope that is ok. Is it??

But get a hanger bracket welded onto new pipe after fitting- drive down to the nearest exhaust place.. Get a new PEC Aus O2 sensor from Vulture Motorsport for 38 bux and drop that in.. If ur exhaust is free flow ALL the way, the difference this pipe makes is worth everything

If you keep the stock cat there no point doing it cause your still putting a huge restriction in the exhaust system

Even if you punch the cat out its still 2.5 inches

I agree you should change the cat, but I wouldn't say there is no point doing it, it's still better than stock. Can still change the cat later if you can't afford it straight up, but I went with a VENOM cat which is a bit more expensive.

Agree dont keep stock cat, get a 3" straight thru cheap lobokka 100 cell metal cat off ebay (5" body).. Yes it was direct bolt on, i rocked up at just jap and the dude there gave me a packet of rubbish gaskets n nuts too so i just used the stock ones which were in great nick, no gasket goo, hope that is ok. Is it??

But get a hanger bracket welded onto new pipe after fitting- drive down to the nearest exhaust place.. Get a new PEC Aus O2 sensor from Vulture Motorsport for 38 bux and drop that in.. If ur exhaust is free flow ALL the way, the difference this pipe makes is worth everything

Ah dude... Do it once do it right hey. Those gaskets are like 6 bucks and very widely available. Never reuse a gasket, they are such cheap little things that can cause so much shit.

I actually didn't notice much difference when I installed mine. Got it after I got my 5" hi-flow cat and 3" custom straight-cut exhaust. Only difference I noticed was the louder induction noise, maybe 100rpm of response, and it certainly didn't make any noticeable difference to power.

I agree you should change the cat, but I wouldn't say there is no point doing it, it's still better than stock. Can still change the cat later if you can't afford it straight up,

If he plans on changing it soon then that's fine but I wouldn't leave the stock cat in place too long

If he plans on changing it soon then that's fine but I wouldn't leave the stock cat in place too long

It shouldn't cause any problems. Might restrict a bit of power/response, not too big a deal. Small possibility of melting the substrate if the boost is increased. It's better to replace it I agree, but I wouldn't NOT do the JJR just because you have a stock cat.

i think that a better way to say it is that replacing the stock cat is probably best off doing before the dump pipe, although doing them both at the same time is the best option, and given that you can get basic 3" cats from under $200 that are more than fine, it isn't that much more expensive to go that way.

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