Do they actually do anything for performance or are they just to scare old ladies and impress young boys? LOL

Originally posted by ChrisC

Do they actually do anything for performance or are they just to scare old ladies and impress young boys? LOL

 

:eek: oh dear now you want to impress young boys

Some answers here:

 

http://www.turbosmart.com.au/faq.htm

 

Q7 in both sections a real duh q

 

Nice ride!

 

What's it done to your insurance premium?

You're options are a little limited mate.

 

I got them, doubt if they improve performance on anything below 20 psi, I just like the sound and I got rid of the goose honk ?.

So what do you want me to vote :confused: :D

I want ones that make a double barrled high pitch noise, sound ace.

Originally posted by smw1

You're options are a little limited mate.

 

I got them, doubt if they improve performance on anything below 20 psi, I just like the sound and I got rid of the goose honk ?.

So what do you want me to vote :confused: :D

 

That sounds like you are a "only because they make a noise" type of person :D LOL

I got them to prolong the life of my turbos in the same respect that I burp after drinking loads of beer to stop my guts exploding. But burping don't allow me to drink any more... maybe a little bit faster. OK, so I like how my beer burps sound but I don't drink because I like burping. I drink cos I'm a f*cking alcoholic. Where was I going with this?

Ok Si, that's fair enough but ask yourself this.

 

How cold does your Stella need to be to be just right ?.

Oh, stop it Stu! Thinking about slushy Stellas... I want one now! But to answer your question: I don't know (simple and to the point). It's probably just over 0 degrees... not quite frozen solid but cold enough to be icey. Or is this a trick question because alcohol has a lower freezing point, or cos the can is pressurised?

 

To answer Mr Groves point... I reckon a pair of those whizzy party blower things stuffed in the ends would sound fantastic. Or maybe the farty bit of a whoopy cushion? Either's better than goosehonk.

Originally posted by 51x

I got them to prolong the life of my turbos in the same respect that I burp after drinking loads of beer to stop my guts exploding. But burping don't allow me to drink any more... maybe a little bit faster. OK, so I like how my beer burps sound but I don't drink because I like burping. I drink cos I'm a f*cking alcoholic. Where was I going with this?

 

Class mate, pure class :D :D

smithy :cool:

Blitz say................................

 

 

Available for nearly all turbocharged Japanese sports cars, Blitz dump valves are supplied with a full fitting kit and interchangeable trumpets for different sounds. The main purpose of the dump valves is to improve the response of the turbo by quickly releasing the boost pressure before the turbo stalls

This looks like the engineering answer:

 

http://www.twinturbo.net/ttnetfaq/FAQpages/bov.html

Sod the theory, I like the noise.

 

:D

I was gonna put a (maybe) controversial but well thought out post about that "theory"... but this is quicker (I don't wanna think about this much more):

 

how can you save the boost pressure you don't currently need somewhere in the system (so it can be used when you do need it) without slowing the turbo down?! It won't happen. The point is you want to dump the pressure somewhere that's at a lower pressure... like the atmosphere. The way I'm looking at it, the recirc valves dumping it from the high pressure side of the turbo to the low pressure side (ie. the intake) it's the same as dumping it to the atmosphere... it doesn't store up pressure for later! If anything it's blowing air that's been heated by the turbo back into the turbo, and possibly up toward the intercooler. IMO you're better off dumping the pressure out of the system unhindered into the atmostphere (it'll be wasted whatever) - the next air the turbo draws in will be fresh and coming straight from the intercooler.

 

Just cos Nissan fit recircs in the original design doesn't mean it's a better idea. There's probably all sorts of things in the 300 engine that seem technologically revolutionary - like variable inlet timing - but in practice you're (probably) better off without.

 

Discuss ;)

Originally posted by 51x

I was gonna put a (maybe) controversial but well thought out post about that "theory"... but this is quicker (I don't wanna think about this much more):

 

how can you save the boost pressure you don't currently need somewhere in the system (so it can be used when you do need it) without slowing the turbo down?! It won't happen. The point is you want to dump the pressure somewhere that's at a lower pressure... like the atmosphere. The way I'm looking at it, the recirc valves dumping it from the high pressure side of the turbo to the low pressure side (ie. the intake) it's the same as dumping it to the atmosphere... it doesn't store up pressure for later! If anything it's blowing air that's been heated by the turbo back into the turbo, and possibly up toward the intercooler. IMO you're better off dumping the pressure out of the system unhindered into the atmostphere (it'll be wasted whatever) - the next air the turbo draws in will be fresh and coming straight from the intercooler.

 

Just cos Nissan fit recircs in the original design doesn't mean it's a better idea. There's probably all sorts of things in the 300 engine that seem technologically revolutionary - like variable inlet timing - but in practice you're (probably) better off without.

 

Discuss ;)

 

intake air goes through the IC's after its been compressed ;)

Originally posted by Clarkey

intake air goes through the IC's after its been compressed ;)

Lucky that wasn't the well thought out version then ;) So where does that leave me?

Originally posted by 51x

Lucky that wasn't the well thought out version then ;) So where does that leave me?

 

Back being an alcoholic! :D LOL

LOL :D Maybe I should stick to what I'm good at?

 

But you can hardly blame me for getting it @rse-faced...

 

"we could direct that pressurized air somewhere else where we could hold on to it until we need it again? The intake side of the compressor housing (between the intercooler and the turbo) would be a good place wouldn't it?"

 

Am I being dumb?! It still makes sense that you can't store up pressure for later. I dunno where he gets the idea recircs can dump enough air for 600+ bhp (2 bar?)... mine started honking at 11 psi. OK, so maybe they were old and busted but at least I know my dump valves will handle 2 bar when I run it... soon ;)

remember though the stock ones arent designed to recirc that kind of pressure, buy some aftermarket ones though and 2 bar wouldnt be a problem.

Originally posted by 51x

but at least I know my dump valves will handle 2 bar when I run it... soon ;)

 

 

And do we know when that will be :( :confused: .

 

Hopefully not too long now :D

2 bar? gulp

Gulp, yeah :) No Stu, I'm not putting a date on it this time... probably won't be running that much by Trax but should (SHOULD!) have the car back at least. Which reminds me, I still need to send that cheque to Ajay.

 

This whole dump valves versus recircs question... can we effectively sum it up by saying uprated recircs could be as good as decent quality dump valves, but are harder to get to and don't burp so loud?

Originally posted by 51x

This whole dump valves versus recircs question... can we effectively sum it up by saying uprated recircs could be as good as decent quality dump valves, but are harder to get to and don't burp so loud?

Errrr, no. You're only going to need uprated recircs if you're stock ones can't take the boost you're running. If your recircs are up to the volume of air, they're always going to be better than throwing away all that air you've spent time charging. With the dump valve, yeah you stop the turbo stalling, but you're running the engine on an awful mixture in the meantime and you're losing all your carefully compressed air. Did you put up with all that lag just to throw the air away again?

 

I'm going to get so much shit for this aren't I?

Errrr, no. You're only going to need uprated recircs if you're stock ones can't take the boost you're running.

Yeah, fair enough... but on mine they were screwed at 11 psi. I could have had them replaced or uprated, but I don't think I've made a mistake considering how much boost I will be running.

 

they're always going to be better than throwing away all that air you've spent time charging.

But I think the point I was kinda making was you throw it away whatever... it can't be stored anywhere without slowing down the turbo (I guess(ed)) and where it's being dumped to with the recirc, it's only benefit seems to be it's dumped back through the intercooler to keep it cool(ish).

 

With the dump valve, yeah you stop the turbo stalling, but you're running the engine on an awful mixture in the meantime

This was another thing I didn't really get from the TTnet stuff... if you've taken your foot off the throttle anyway, the ECU will know not to inject tons of fuel... not that it really matters anyway because the throttle's closed... so if anything it might chuck a bit of fuel out the exhaust where it doesn't need to burn it at that time... which (maybe?) helps keep the turbo's spun up? This is all such a total guess on my part, of course.

 

and you're losing all your carefully compressed air.

You'll be losing it whatever. No? It can't stay compressed or it wouldn't get dumped.

 

I'm going to get so much shit for this aren't I?

No. Why? It's just harmless discussion. I'm no expert (obviously).

Hi mate.

 

The recircs basically create a closed loop between both sides of the inlet part of the charger. Therefore this is now a closed system containing charged (i.e. boosted) air. This will not escape anywhere and the turbine is basically freewheeling, pushing this charged air around the loop. Yeah, the turbine will slow down, the same way a fan in a normal atmospheric pressure slows down when you switch it off. But it won't stall.

 

When the throttles open again, the air is still charged inside the loop.

Oh yeah, and the mixture thing. It's how much air is going through the AFM that counts, not how much enters the engine. If you dump the charge to atmosphere, there's still a large volume of air entering the AFM to replace the air drawn through the turbo as it slows down. Appropriate quantities of fuel are therefore injected to compensate. You basically have an enormous boost leak.

 

The drawbacks of this may be debatable however. I presume you haven't got any cats. Although having that quantity of unburnt fuel passing through my very hot exhaust turbines would worry me. Don't know enough about that bit though.