Jump to content
SAU Community

Recommended Posts

All RB's sound slightly different to one another yet still sound similar.

Like most of the time, you can tell the sound of an RB25 exhaust note to an RB20.

however, the RB26 sounds different to all of them.

my question is what is it that makes it different?

It just sounds alot tougher than the other RB's.

so what is the reason for this?

At idle, or cruising on WOT.

they just sound ALOT tougher than the other RB's.

is it the fact that there are 2 turbos?

is it the individual throttle?

is it cams?

I understand that the exhaust system has a lot to do with it, but no other RB sounds quite like an RB26.

I don't want replies like "because teh GTR can neva lose" or something equally stupid.

This is a serious question on what gives the RB26 an angrier note.

Link to comment
https://www.sau.com.au/forums/topic/73697-rb-sound-differences/
Share on other sites

  • Replies 60
  • Created
  • Last Reply

Top Posters In This Topic

i'd say the twin turbos would have fark all to do with it. like abo said a big part could be the solid lifters, multi throttles would also change the note. plus head design inlet and exhaust ports shape would have an effect.

All these differences contribute. That's why a Ducati sounds different to a VTR Honda, which is different to an RSV Aprilia. They are all twins and - different cans aside - the Ducati still has a distinct exhaust note primarily due to the valve train design. Hence the Desmosedici head engines sound different again to their predecessors.

they (RB26's) just sound ALOT tougher than the other RB's.

sorry but ill have to flat out disagree with that! :D

i do definitly agree they sound different, and from my own description id tend to say they sound more "mechanical" in their note. I think you need to hear my 25 at full noise :D

From the 26's ive heard, i reckon the 25's have a "sweeter" and more "howling" note, and not as harsh sounding as 26's. As for reasons why, i think theyve all been covered. Of course exhaust systems are going to make each and every one sound different so i guess it comes down to personal preference.

its also very possible that i just havent heard a really nice sounding 26!

cheers.

Any one who has changed thier turbo to a larger item will know how the exhaust becomes louder and more angry sounding. :D

I've heard RB25's that sound mighty tough. It simply comes down to the exhaust.

The RB30 sounds a little deeper than the rb20, it does sound nicer, especially if I jam the wastegate open it becomes much louder and brup brup sounding. :D

Since converting the RB25 to a GTR34 twin turbo setup, the difference is in the fact that the 2 turbos separate the pulse of the front and rear 3 cylinders. They don't merge until after the firewall. It was very noticeable, especially with another 25 to compare to in the garage.

I have the HKS style split pipes as well so it is a bit louder, but it all bolted straight up to the single cat location :D

So while some of these other points are slight contributors, it's mainly the turbo configuration. And, It sounds PHAT as hell :D

they do sound more mechanical and that is what I would say is tough.

get a stock rb26 with an exhaust and any other stock RB with an exhaust, and the rb26 sounds a lot more angry, mechanical, harsh, tough.... what ever you want to call it.

I just like it and wanted to know what caused it.

I don't agree that it's the turbo's.

if that were the case, then an rb26 with a large single would sound like an rb25 with a large single..

but it doesn't.

still sounds more mechanical.

I'm going to go with the thought that it is the combination of cams, exhausts ports (if they are infact different), throttles...

Since converting the RB25 to a GTR34 twin turbo setup, the difference is in the fact that the 2 turbos separate the pulse of the front and rear 3 cylinders. They don't merge until after the firewall.  It was very noticeable, especially with another 25 to compare to in the garage.

I have the HKS style split pipes as well so it is a bit louder, but it all bolted straight up to the single cat location :D

So while some of these other points are slight contributors, it's mainly the turbo configuration. And, It sounds PHAT as hell :D

It's ALIVE!! I want a spin in it

I don't agree that it's the turbo's.

if that were the case, then an rb26 with a large single would sound like an rb25 with a large single..

but it doesn't.

still sounds more mechanical.

I'm going to go with the thought that it is the combination of cams, exhausts ports (if they are infact different), throttles...

Sure mate, and you compared this to a handy RB25DETT just to tell me I'm wrong. Thought you'd appreciate an answer from someone who has done the conversion and speaks from experience, but obviously you didn't need help.

Yep, up close with the bonnet up the solid lifters cause a fair bit of mechanical rattling, but even after yesterdays cruise with variously configured GTR's to listen to from inside the nice quiet Soarer there is a distinct difference between singles and twins (and the luxobarge gave me plenty of chances to get passed :D)). A lot to do with the various exhaust systems as well with similar single or twin configurations.

As far as the cams go, I fitted a set of GTR cams and found the top had a bit more power at the expense of low rpm, but it wasn't a different note.

In fact, with a blind comparison I'd suggest none of us could tell the difference. Most well worked GTR's that stick in the mind with a great note are bolted together with good quality kit, including the exhaust. I'd suggest most are just a little too overawed by the whole GTR "thing". I'm no detractor of the GTR, in fact I expect to be buying a GTR33 next month to take the garage to 5 slots, but there is a lot of "it's a GTR so it's too cool".

Compare the Fujitsubo Jasma system on my track car to after the TT conversion and it changed dramatically, the only difference the TT setup I fabricated. Then I put a 3.25 Trust Jasma system on my auto 25t and it's a lot different again, but the NA 33 that it came off made it sound a bit coarse. Next I'll put the 3" front pipe on the auto and I bet it changes again.

Marcus,

it dropped compression on a couple of cylinders at 5psi boost in second after I installed some injectors that I stupidly didn't check for flow rate. Looks like another rebuild before that ride mate, but it was nice until it lost power.

geoff - please don't be offended.

I haven't heard a 25dett.

I have heard 26dett and 26deT and the exhaust note wasn't that different.

it was different... but not much. It still sounded much like a gtr then any rb25det with large turbo that I have been in or been behind to hear the exhaust.

I didn't mean to say that you were wrong..

I just assumed that the other things listed would give the car the rougher sound.

maybe useful to split sounds up into:

induction - filter/s, compressor/s, bov/s, throttle/s, plenum

exhaust - manifold design, turbine/s, wastegate/s, cat, muffler

engine - I am no expert but from above lifters, capacity???? RB20, RB25, RB26, RB30

induction/exhaust noises may more depend just on the turbo system bolt on design (ie single, twin, big, small) and the exhaust gas potential of the engine

what do the N/A versions of these engines sound like with an exhaust, say an rb25de - are they almost louder because the turbo doesnt 'muffle' the exhaust note??

GTST, none taken, and sorry to come across as if I was. I know what you are getting at though, but the TT really changed the entire sound from idle to further up the revs. It was already pretty good but after it just transformed and it confirmed the reason that particuler note comes from the 26. Plus mine also is a 2.6 in capacity now so that is not a huge factor in sound, but it has improved off boost torque due to increased compression.

The 25DE is a fair bit louder with the same exhaust as I had the opportunity to hear when I bought the Trust. I did the swap right away off the other car which got the stock cat back and it went from a sharp loud bark on the DE to a sweet deep rumble on the DET.

BTW the auto is stock except for the zorst and is an absolut POS power wise. Any boost over 10psi and it cuts hard. Any under 8 and it is a big doughy mess.

I agree the RB26 sounds tough.....

Personally dont know why..

Altho ive been told my gtst sounds similar to a GTR when in high revs..

So i dunno...

Just thought id share 26's do sound awesome..

The RB30 sounds a little deeper than the rb20, it does sound nicer, especially if I jam the wastegate open it becomes much louder and brup brup sounding. :D

The RB30 sounds like a commonwhore... in which it is.. Yes a bit deeper, but yucky.

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

    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
×
×
  • Create New...