Jump to content
SAU Community

Recommended Posts

Fitting an exhaust myself today. It's a full turbo back system.

Just wondering how much boost will I be running? And is it safe? Everything else is stock.

I don't have a boost controller yet and I don't want to risk decimating my turbo.

I didn't think it would be an issue since R33's only run 7psi standard and I couldn't imagine it leaping high enough to cause damage. But best to be safe.

I tried searching but this is urgent.

Cheers

Link to comment
https://www.sau.com.au/forums/topic/275651-quick-question-about-boost/
Share on other sites

have u got a boost gauge? your right they run 7psi stock (this is after 4500rpm, before that its 5psi) but they tend to run up to 9psi after upgrading the exhaust and cooler, this is normal & safe

technically speaking the boost shouldn't actually rise at all. this is because the boost is controlled by the wastegate and it will still open at the same pressure. i never saw a boost increase from full exhaust and cooler. however other people have.

I just have the standard boost gauge in the dash. So I have no idea.

But thanks for the information everyone... It helped massive.

My mate fitted it all today after eight bloody hours. Got him to do it as he is in the trade and knows more about the right way to undo and tighten bolts. Took so long as there was a few brick walls to jump when fitting.

Not a fan of the system. Way too loud... It drones under load so much it hurts and it does not sound like a RB anymore if that makes sense.

Hopefully it is worth the performance after I give it a bit when it wears in properly.

what sort of exhaust did you get for it to be super loud? i had a 3" off the turbo to cat then 3.5" from cat back and it wasn't very loud at all.

does it still have the centre muffler in it?

as for it taking 8 hours, wow. i'm guessing a broken bolt/stud on the turbo, because otherwise it is a very straight foward job and shouldn't take more than about half an hour.

what sort of exhaust did you get for it to be super loud? i had a 3" off the turbo to cat then 3.5" from cat back and it wasn't very loud at all.

does it still have the centre muffler in it?

as for it taking 8 hours, wow. i'm guessing a broken bolt/stud on the turbo, because otherwise it is a very straight foward job and shouldn't take more than about half an hour.

It was the full JJR system with the Xforce Cat. It is the loudest I would go for an exhaust in this car but the only problem is that it drones under load. Can hurt the ears. There is no centre muffler with this system.

It took so long because one of the bolts to the turbo was pretty hard to get to. We didn't have the right tools to reach it and the bolts thread was slightly stripped. And the who ever welded the cat was the worst welder. They left a blob right where the sensor goes so we had to drill it out to get it to fit.

If it all went smooth then it would have taken half the time. Oh and we got Macca's so that took up time haha.

I will give my final thoughts on the system once it wears in a bit. For the price it's still a great buy regardless. Just wish it sounded a bit more smoother.

it is probably due to the rear muffler they use. the body of the cannon probably isn't quite big enough to allow enough packing between the baffle and the outer body to take enough noise out of it. also being stainless probably makes it a bit louder. if you still don't like it in a week or 2 just go to an exhaust shop and get a better muffer put on, like a large 3" oval muffler such as a lukey ultra flow. that will make it a fair bit quieter.

technically speaking the boost shouldn't actually rise at all. this is because the boost is controlled by the wastegate and it will still open at the same pressure. i never saw a boost increase from full exhaust and cooler. however other people have.

+1

it is probably due to the rear muffler they use. the body of the cannon probably isn't quite big enough to allow enough packing between the baffle and the outer body to take enough noise out of it. also being stainless probably makes it a bit louder. if you still don't like it in a week or 2 just go to an exhaust shop and get a better muffer put on, like a large 3" oval muffler such as a lukey ultra flow. that will make it a fair bit quieter.

Yeah that sounds like a good idea. But I might start catching the train to work so this will be my weekend car soon enough. I will be more reluctant to put up with it.

You are right about the stainless part. Never been a fan of stainless compared to mild steel as far as sound goes.

It was the full JJR system with the Xforce Cat. It is the loudest I would go for an exhaust in this car but the only problem is that it drones under load. Can hurt the ears. There is no centre muffler with this system.

It took so long because one of the bolts to the turbo was pretty hard to get to. We didn't have the right tools to reach it and the bolts thread was slightly stripped. And the who ever welded the cat was the worst welder. They left a blob right where the sensor goes so we had to drill it out to get it to fit.

If it all went smooth then it would have taken half the time. Oh and we got Macca's so that took up time haha.

I will give my final thoughts on the system once it wears in a bit. For the price it's still a great buy regardless. Just wish it sounded a bit more smoother.

there is a huge difference between stock and aftermarket exhausts mate, dont worry you will get used to the noise and learn to love it!

  • 5 weeks later...

Yeh had the same system and im not sure whether it wore in or i got slightly deaf.Either way sounded awesome on boost.Actually have it from catback still in the garage if anyone is interested.Its also had a hotdog resonator welded in but the resonator is in mild steel.

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

    • Yeah its bad eh. Ey! Watch your mouth. Yep, spot on. The rear's are always gone too though from brake checking. I had them perilously close to a tree that we had taken down. I think the tree peeps may have taken it. Either for a trophy, or accidentally.  
    • f**kin' yikes! That insulation is the shittest stuff I have ever seen. You need to do an insurance job on that f**ker, pronto. WRT to the washer cover, I would have said that there'd have to be some at a wrecker, then remembered that it's a BMW, and reasoned that every single wrecked one would have been tailgating and so the front end would be trashed.
    • Oh and I lost my headlight washer jet cover!
    • Ok, so I got myself some X1 wheels really cheap to try out, they're a bit different and I like them but they're really narrow (18x8) they are available in staggered 18x8/9 also but really hard to find.  I kinda dig them, but not as much as the F10 19's I usually run, so these go into the wheel pile.         As I mentioned in another thread, I got a new exhaust. It's an off-the-shelf stainless one that fits OH-KAY. I don't love the tips size and how far they come out the back, I think I might cut the tips off and replace with some smaller (~3") ones that don't extend as far. It sounds really good though, I'm not sure if its just in my head but the car feels a little quicker, more responsive.      I fitted an eBay special front lip. Surprisingly it fit perfectly and all holes lined up. Its a little rickety but I haven't put any double sided tape on yet, I want to clean the front bar up where it has scraped the road a lot and fil in the number plate holes (or, get body coloured wrap to cover them - is this a thing?  I'm not sure if I'll leave it gloss or pain it matte. I really like it though, I don't particularly like the front bar without it, I don't really like the M-Sport and to get anything else is just too expensive. That said, I might need a new one now anyway as I dropped the car onto the jack after forgetting to put ramps under the front wheels. It bent a lot and while it did go back to normal after I got the car off the jack, I do fear I have not done it any favours.    Lastly, my headlights died. Different problems in each. They have gotten much dimmer over the past year or so, I put new (uber expensive) OSRAM bulbs in them but to no avail. One of them pointed at the ground and the other just kinda did its own thing with light working sometimes. Yeah, check this 18 year old BMW headlight wire. I reckon I know why they were stuffed.            BTW, the yellow and black is the power to the Xenons. Yikes. I hunted around an researched my options here. I would have loved to just get a replacement harness but not a thing. My car has adaptive headlights, that is they rotate left and right with the steering wheel. Good condition used adaptive xenons were over $700 each, non adaptive were around $400 each, but I couldn't help but think that they're all around 18 years old now, surely they'd have the same problems. So I looked at newer LCI headlights but they were even more expensive and I couldn't confirm that they'd be plug and play with lots of people having lots of opinions so not worth the risk.  I ended up getting brand new Chinese headlights from MARS. They're very close to OEM with only the angel eyes being a bit different. I didnt want crazy turn signals or sharp DRL's or anything. Not my bag.  They're not adaptive, I thought thats a feature I wouldn't really miss. So I coded that out.  The lights are awesome, they look so nice and they take so many years off the car. The angel eyes look great and the headlight brightness is ridiculous. I was so used to the old ones, I didn't realise just how bad they were. The new ones use the OEM bulbs, Xenon ballast and leveller motor which I was happier with. The only issue with them is that the rear cover is held on by SEVEN screws. This will be a nightmare to get to and open when I need to change bulbs.   
×
×
  • Create New...