for those with afraid of turbo lag...

[StricNyne]

http://www.hopupracing.com/saextocovana.html i just seen this and wow i wish i could find some reviews on it i am highly interested since it looks like a cat i would pass visual inspection with it also

[Kansei240sx]

Yeah, those are actually pretty badass, they look just like a organized cat on the inside and flow pretty good but catch alot of emissions.

[Joe]

somehow i doubt that helps with emissions.

[StricNyne]

emissions is for nerds... well actually emissions is for people who dont want to be harassed from cops !! thats a modified quote from assy mcgee

[mello88]

How do these "torque control valves" work?

My understanding is they have a plate/cone to seal off exhaust flow and thereby raise backpressure. This plate/cone is on a spring suspension similar to a BOV, which opens under high exhaust PSI. Allowing for high backpressure at low rpm/low exhaust flow times, and low backpressure at high rpm/high exhaust flow times... Is this accurate?

I'd like to see a dyno chart showing what gains this adds, or what top end restriction it presents.

And unless it has a 2 part catalyst honeycomb in there, it won't do anything productive for emissions...

[StricNyne]

to be honest i dont care, if it looks like a cat, and i am tuned properly i will pass emissions i would think i just care about the fact that it will make my snail spool a lil faster

[OpeLok]

[Chaos the Xile]

NOT THE TORNADO! and F- Emission, no such thing in Ohio!

[StricNyne]

i said i wanted to make my turbo spool faster not twin charge it !!!

[Bronze MFP]

ok who's gonna guinne pig this thing? its made by SARD, so it shouldn't be BS right? RIGHT?

[StricNyne]

i might... but i wont be running for a while...

[Carl H]

its a pretty simple principal, increace backpressure to aid in scavaging at low rpms...might end up being a restriction tho on cars making decent hp.

[Bronze MFP]

well since you're making mad powaz carl, you try it

lets get a before and after dyno

[jdm_master_X]

id rock it. if only i had the money. well if all goes well, ill get it in a few weeks.

[cdorhout]

I've never heard of backpressure helping turbo perfornance. In fact, I've heard quite the opposite. Get the exhaust out as fast as possible. I'd never put that in my exhaust.

[Sil240]

Forget that backpressure cat thingie.Get this:http://paultan.org/archives/20...-work/

BMW twin turbo diesels and Porsche turbos

[DriftingisLame]

I've never heard of backpressure helping turbo perfornance. In fact, I've heard quite the opposite. Get the exhaust out as fast as possible. I'd never put that in my exhaust.

God, finally someone said it.. I felt like I'm taking stupid pills or something!

Backpressure aids in low rpm torque on NA motors that dont already have a huge *** restriction in their exhaust flow (Turbo). Why would limiting exhaust flow make your turbo spool faster....?

Seems like one of those blingin JDM parts thats better fit for a hachi roku dorifto machine.

[002-M-P]

I've never heard of backpressure helping turbo perfornance. In fact, I've heard quite the opposite. Get the exhaust out as fast as possible. I'd never put that in my exhaust.

Exactly what I was thinking too. The turbo itself creates alot of backpressure on its own. That is why turbo cars are generally quieter than naturally aspirated cars. The general rule is (can't remember who said this) "the best exhaust for a turbo car is no exhaust at all".

[DriftingisLame]

I believe I read that in Maximum boost by corky bell. I think after that he went in to a little more detail, and said that the ideal exhaust would be about a 6" long cone thats there purely for heat direction reasons, not restriction.

[chockrl]

Has anyone heard of Yamaha's EXUP valve? It is a butterfly valve in the exhaust to increase lowend torque on sport bikes. They have had it since the early 90's and probably earlier. They are all NA, so don't know what it would do for a turbo and response.

[ISUJinX]

I've heard of the EXUP valve ... It's crap :-p There is so much to be gained from an aftermarket pipe and a little bit of timing or porting, that the low end torque problem is all but minimised. Besides... If youre running a sport bike under its powerband - you aren't riding hard enough .

For forced induction cars (supercharging too) The free-er flowing the exhaust, the better. Hands down, no questions asked. And as for N/A cars - you are better off with properly sized/stepped headers (of the right length) to aid in scavenging - rather than putting a "torque-valve" in. Exhaust restrictions fall into the same category as the electric superchargers we saw on ebay oh so long ago.

[240z4u]

IMO that thing does not look like any cat I have ever seen. If your that worried buy a magnaflow and gut it.

I do have a cat on my car btw.

Evan

[tyndago]

Theres plenty of backpressure in a turbo car. Its between the exhaust port and the turbine inlet.

You don't want any more back pressure after the turbocharger. More backpressure equals less power.

I have found that spool up improves with a shorter less restrictive exhaust. 12 whp on the last car we put on a dyno.

[Carl H]

lol never said that it was a good idea to have backpressure i was simply speculating on what it did...