Installing Jjr Bellmouth Front/dump Pipe On R34

[V28VX37]

Hi all,

I just got one of those JJR bellmouth front/dump pipes for my R34 GTT and was wondering if you had advice and tips on installing it. Some questions:

1. Can this be installed with the front on jack stands or do you need a hoist?

2. Do you recommend separating the dump from the front pipe or just pulling these out together?

3. The flange on the stock dump is heaps thicker (about 18 mm) than on the JJR (~8 mm). Can I still use the original bolts or do I need to get some shorter ones?

4. Should I put the heat shield bracket (see 3rd photo) back in with the new pipe? I don't think the bolt holes will line up (with the heat shield) given the difference in flange thickness.

5. There are six bolts altogether. How do you access the bottom two?

6. Any tips on how to avoid snapping the bolts when taking them out? They've been on for the whole 100,000 km I reckon. I've started soaking them in WD40, hope that helps...

Thanks heaps guys.

[ClutchBurndout-:(]

Hi all,

I just got one of those JJR bellmouth front/dump pipes for my R34 GTT and was wondering if you had advice and tips on installing it. Some questions:

1. Can this be installed with the front on jack stands or do you need a hoist? just jack it up

2. Do you recommend separating the dump from the front pipe or just pulling these out together? ive always pulled them out together

3. The flange on the stock dump is heaps thicker (about 18 mm) than on the JJR (~8 mm). Can I still use the original bolts or do I need to get some shorter ones? use the standard ones

4. Should I put the heat shield bracket (see 3rd photo) back in with the new pipe? I don't think the bolt holes will line up (with the heat shield) given the difference in flange thickness. dont stress about the heatsheilf, u have it heatwrapped anyway

5. There are six bolts altogether. How do you access the bottom two? the bottom 2 will be nuts not studs/bolts, get under the car and you can access them easy as pie that way

6. Any tips on how to avoid snapping the bolts when taking them out? They've been on for the whole 100,000 km I reckon. I've started soaking them in WD40, hope that helps... there gonna be hard, but ive done the same on pipes that havnt been removed after a long time, i have however snapped one in the turbo flange (lucky i was replacing the whole turbo, just make sure its wd40d alot, soak it for a few hours, while going back to respray every 20 mins! make sure you havnt run the car as the bolts will expand in the flange from the heat making it harder to remove, and also losen all nuts equally so the flange dosent lean onto other studs. other than that there aint much u can do

Thanks heaps guys.

read my bold replies above

also, the heat sheild comes off first, so u can access all the 4 top nuts, then the 2 underneith are from under the car with a spanner (i dont think u can get a rachet on them) also, if ur jjr pipe is the same as mine, which i think it is, you wont be able to get the passenger side bolt back in, as the pipe warps over it, i wouldnt stress to much on it, the bottom and top bolt/nuts should stop any leakage

[V28VX37]

Brilliant, thanks heaps for the tips Clutch!!

make sure you havnt run the car as the bolts will expand in the flange from the heat making it harder to remove, and also losen all nuts equally so the flange dosent lean onto other studs. other than that there aint much u can do

Here's what MAG86 suggested in another thread, although he's talking about the manifold bolts:

and the manifold bolts, well what i have done (on 4 different L24's) is just as i pull up in the garage, pop the hood, let it cool for a little bit, and while its still hot, spray a heap of wd40 on the studs/nuts. then leave it for an hour, then do the WD40 again but cold this time... and let it soak until the next day. they come undone so much easier then!

I might give it a go spraying them hot once and then multiple times again when cold, shouldn't hurt.

Cheers

[ClutchBurndout-:(]

Brilliant, thanks heaps for the tips Clutch!!

Here's what MAG86 suggested in another thread, although he's talking about the manifold bolts:

I might give it a go spraying them hot once and then multiple times again when cold, shouldn't hurt.

Cheers

wouldnt hurt! the longer u soak it the better though, ive heard of people soaking old commodore door hinges for a week so the pins come out, so if you soak it like you said and still no go, keep soaking

[SECURITY]

the bottom bolts are a bit of a bitch to get at. you need a 13mm spanner. you will most likely use the open ended side when putting them back on.

what i do to prevent snapping bolts is 'crack' them first. drench in WD40, tighten again, then loosen while still feeling if it gets rough. if you feel it start to get a bit rough on the way out just spray some more WD40 then tighten then loosen. my bolts have done 220,000km and have been on and off around 10 times - havent broken one yet.

as for the spacing, i always use 2 gaskets. the stock and the one they give you. just make sure you carefully match the flange to the size of the exhaust by grinding it out a bit.

also dont freak out when there is a bit of smoke coming from the area after you start it up the first time. greasy hands, WD40 and heat will do that. just keep the car on stands so you can listen out for any exhaust leaks.

[gotRICE?]

you wont be able to get the passenger side bolt back in, as the pipe warps over it, i wouldnt stress to much on it, the bottom and top bolt/nuts should stop any leakage

What you do to get around this, is move that stud to a different location.

You need to have the bolt in the hole on the dump pipe as you fit it, and do it up as you slowly push the flanges home. Dont just stick it on and then try get the bolts in It takes time. But you will feel rewarded for it at the end haha

I managed on mine, so everyone else should be able to too

And, x2 on the smoke. It goes away pretty fast. Just take it for a good beat and it will burn off all the coatings and start changing colour.

Edited July 30, 2010 by gotRICE?

[SECURITY]

forgot to mention... unplug the o2 sensor and undo it off the car, dont even bother trying to do it while the dumps are on the car because you just wont succeed without the proper tools.

[gotRICE?]

forgot to mention... unplug the o2 sensor and undo it off the car, dont even bother trying to do it while the dumps are on the car because you just wont succeed without the proper tools.

^ This. Good advice. Soak that bastard with CRC or whatever too. You'd possibly need a mate to help you, as holding the dump pipe down and getting the appropriate leverage to crack the sensor is next to impossible without lifting yourself off the ground haha. Shocking it is key, brute force didnt seem to work well for me.

And just something else, id also recommend putting high strength high temp lok tite on the thread rather than doing it up really tight. In my experience with the JJR stainless dumps, the stainless steel seems to enjoy holding onto the sensor for all its worth and stripping it out if you ever need to remove it for some reason.

[V28VX37]

Great advice, thanks everyone! I'll give it a go over the next week.

Re O2 sensor, I thought as much. I tried replacing it not long ago (on the stock dump) but no way can you get it out without the special tool below when the dump's still in the car:

[GUN_METAL_GTR32]

ive got one of these front pipes on my rb25 and we snapped the first bolt haha.

there a flamin mongrel to do and a hoist would make it so much easier. we used a hoist

[V28VX37]

Gave this a go today. All went well, I kept soaking the turbo bolts and nuts and didn't break any of them, yay. Stock dump & front came out easy enough, although the long fixed bolts on the stock cat suck.

Swapped the O2 sensor to the new pipe no dramas, popped it in loosely and started looking at the cat. What the h___, the flange doesn't like up?!

It's an XForce 3", part number ES-NR32-02-CAT. It says R34 GTT on the box too. The front flange seems to be the problem, it seems more slanted than on the stock car:

Front:

Rear:

Has anyone else seen this?? Please don't tell me coupe and sedan have different cats?

Also just to confirm, the arrow on the cat is the exhaust gas flow direction right (i.e. pointing towards rear of the car)?

My JJR front/dump was on a sedan before so that should be fine...

[ClutchBurndout-:(]

how far off is the flanges? it looks ok to me. can you explain further whats wrong?

[gotRICE?]

You just looked at it? Or did you try? It might be ok.

[V28VX37]

how far off is the flanges? it looks ok to me. can you explain further whats wrong?

You just looked at it? Or did you try? It might be ok.

Yep tried it on, XForce rear bolts fine to the stock cat back (cat is straight & level) however with one front bolt on the other bolt holes are 10-15mm apart. Tried forcing it but they still wouldn't line up to get a bolt through.

It's hard too see it in the photos but the front flange appears slightly more 'rotated' on the XForce. I may have to take it to an exhaust joint to be cut & rewelded, sucks though as I thought it was a straight bolt-on...

[gotRICE?]

it should be. someone muffed it up when they made it. cant you just take it back and get a new one?

[ClutchBurndout-:(]

i dare say he got it from justjap, so more of a trouble sending it back than to just get a zorst joint to fix it, wont be expencive.

are you 100% sure that the stock zorst wasnt twisted which would result in the flanges not lining up?

and u sure its not back the front?

[maddowse]

get a mate to lie under the bacl of your car and push up on the mufler dude when you have taken off your cat the mufler will cause the exhaust to twist on the rubber hangers

[SECURITY]

get a mate to lie under the bacl of your car and push up on the mufler dude when you have taken off your cat the mufler will cause the exhaust to twist on the rubber hangers

+1

thats usually the case. i usually get a car stand to hold up the exhaust if i cant get a mate to twist it for me. keep ALL bolts on the cat (front and back) loose till you get it lined up. when they get closer nip them up then continue to tighten.

[ClutchBurndout-:(]

if it is however twisted but you get the cat on, it will put a lot of pressure on the dump pipe-turbo studs and even the manifold studs to the block

[gotRICE?]

if it is however twisted but you get the cat on, it will put a lot of pressure on the dump pipe-turbo studs and even the manifold studs to the block

I was thinking exactly this. And seeing as they are known for snapping under OEM conditions it wouldnt be ideal. Chop and weld could be the best. Or if its not too much, file out the holes a touch.