Prefered exhaust design poll?

[Leon.]

DOH!!

Cheers Craig!! So..... what is the outer diameter of the tailpipes then pls?

Cheers

[craig]

DOH!!

Cheers Craig!! So..... what is the outer diameter of the tailpipes then pls?

Cheers

Piping diameter: 75mm decreasing to 65mm(Regular) or 85mm (Pro)
Tip diameter: 115mm
Exhaust material: Part stainless steel
Number of tips: Dual
Number of mufflers: Dual


HTH

Craig

[Leon.]

115mm......mmmmmmmm

Sounds phat!!

Cheers mate, enjoy..........!

[Shadow]

The stock exhaust is 70mm (outer dimension), I'm surprised Departure is only 85mm. It looks more like 4"/100mm??!!

Sorry, I thought you were after some useful measurements

But as RedMR² said the tips are 4.5 inch's, but why did you need to know the tip measurements Vs the internal diameter measurement? Just curious

[Leon.]

Sorry, I thought you were after some useful measurements

But as RedMR² said the tips are 4.5 inch's, but why did you need to know the tip measurements Vs the internal diameter measurement? Just curious

Its purely cosmetic reasons - I'm just deciding what diameter tips to get on my custom made Blueflame



I want rolled-in tips so, probably gonna go for 3.5" or maybe even 4"??

[Shadow]

Its purely cosmetic reasons - I'm just deciding what diameter tips to get on my custom made Blueflame

Aah I see, thought as much In my opinion a 4" tip would suit the mr2 bit better, make it look a bit more aggressive without looking too OTT, especially on rolled-in tips. Unless you want it stock looking?....I've got used to looking at the Departure's 4.5" tips and they don't seem too OTT

[shahid rashid]

[Leon.]

Shadow wrote:

Aah I see, thought as much In my opinion a 4" tip would suit the mr2 bit better, make it look a bit more aggressive without looking too OTT, especially on rolled-in tips. Unless you want it stock looking?....I've got used to looking at the Departure's 4.5" tips and they don't seem too OTT

I think 4" too, the rolled in tips will make it look a bit smaller. Being that the stock is 2.75", another 1.25" aint that much, just enough to look

If I got 3.5", I'd hate to then decide DOH its too small, need another new exhaust!!!

Not that I can afford 2 of course

[Bry]

Hi all,for looks the D2, but for performance the blitz, why , well the departure exhausts have a V in the pipe to deflect the exhaust gass's to the pipe outlet's either side, which disturbs the exhaust pulses therefore reducing performance .The Blitz keeps the pulses of the exhuast gass's flowing with minimal ristriction to the flow.
Pulses need to flow as pulses at what ever given exhaust exit speed with minimal ristriction on turbo cars to help with the exhuast flow.The turbo is already a big ristriction.So its the blitz for me.
PS,do your research

Pheonix power managed to get 700bhp with a departure 2 pro fitted,so not that restrictive really

[Shadow]

Hi all,for looks the D2, but for performance the blitz, why , well the departure exhausts have a V in the pipe to deflect the exhaust gass's to the pipe outlet's either side, which disturbs the exhaust pulses therefore reducing performance .The Blitz keeps the pulses of the exhuast gass's flowing with minimal ristriction to the flow.
Pulses need to flow as pulses at what ever given exhaust exit speed with minimal ristriction on turbo cars to help with the exhuast flow.The turbo is already a big ristriction.So its the blitz for me.
PS,do your research

Hmm, if you went by that analogy you could say that the blitz was restrictive becuase it’s a big bendy snake! Granted being a duel design you do get some air flow disruption, but the departure (and some other duel exhausts) flows more gases to one side, which indicates the air flow isn't as disrupted as you might think. The blitz is designed to obviously be as un-restrictive as possible, but to give better and enhance mid range power hence, all the bends. Whereas the departure is more suited to higher in the rev range. In fact both of these exhausts are more restrictive than a straight through system with no muffler, but what does that matter? It would be nice to get someone to dyno these exhausts back to back, I really don't think there will be any significant difference and as Bry has said Phoenix Power have used the departure on a number of high powered cars. You seem to be knowledgeable with the design of the blitz, would you care to share where you got all your info, or did you test it yourself?

[Bry]

Just to add,I've tried(BACK TO BACK) a HKS Hyper muffler,a Blitz Nur spec and a Departure 2(pro) exhaust on my car and to be honest I couldn't tell any difference in performance between the three,I'm not saying that one might not give a few bhp than the others,it's just on the road you can't tell,IMHO

[shahid rashid]

[Bry]

Hi all, Phoenix power had a larger bore d2 and the back boxes were of minimal restriction design for 700hp, completly different to the normal d2 that they sell on the market.Do ur research, people will sell u anything quoting that its capable of this and that.
I have tested both on the rollers and looked at the exhuast temp on both, the d2 exhaust temp was higher than the blitz, which mean that if a exhaust is restrictive it will generate more higher exhaust temp, because the gass stay's in the exhaust longer therefore higher gas temp is generated.
I tested the exhaust's on a 1995 rev3 turbo running @ 1.3bar with hks airfilter and greddy intercooler.
As for blitz even that is restrictive at around 400hp and if u go higher it gets worse .I have gone through several exhuast design's and so far i have come to the conclusion that a staight through with a very minimal restrictive backbox works well.Because i am giong to be running 2.5 bar on the T78 i need a custum . I do agree that the blitz is a long and very bendy and does also restrict, But for looks its the D2 depending on how much hp u want to run and blitz if u want alitle extra hp and performance .

You keep going on about doing your research,well you should take your own advice, as you say you measured the Departure 2's exhaust gas temp and it was higher than the Blitz.The hotter the exhaust gases are the faster they will flow as they are less dense(lighter).If you have cooler exhaust gases they will be more dense(heavier)and your pistons will have to work harder to expel the cooler heavier gases from your exhaust.This is one(I know there are others) reason why people wrap manifolds in insulating materials as this reduces any heat loss thus keeping gas temps high and faster flowing.So by your own reckoning the Departure 2 system produced higher gas temps,which means it's the better flowing system.There are 2 different Departure 2 systems, the regular system and the pro system,it's the pro system that was used on the 700 bhp demo car and yes it is available to the public.
Please drop the condescending attitude,we can do research too you know

[Shadow]

Hi all, Phoenix power had a larger bore d2 and the back boxes were of minimal restriction design for 700hp, completly different to the normal d2 that they sell on the market.Do ur research, people will sell u anything quoting that its capable of this and that.
I have tested both on the rollers and looked at the exhuast temp on both, the d2 exhaust temp was higher than the blitz, which mean that if a exhaust is restrictive it will generate more higher exhaust temp, because the gass stay's in the exhaust longer therefore higher gas temp is generated.
I tested the exhaust's on a 1995 rev3 turbo running @ 1.3bar with hks airfilter and greddy intercooler.
As for blitz even that is restrictive at around 400hp and if u go higher it gets worse .I have gone through several exhuast design's and so far i have come to the conclusion that a staight through with a very minimal restrictive backbox works well.Because i am giong to be running 2.5 bar on the T78 i need a custum . I do agree that the blitz is a long and very bendy and does also restrict, But for looks its the D2 depending on how much hp u want to run and blitz if u want alitle extra hp and performance .

I think Bry has said it all really, but i'll ad a few further points. You seem to think you know about the departure and blitz exhaust, you may well do but i'd be interested to hear where you got the info on the statement saying Phoenix power didn't use their own exhaust available for the mass market in their high powered mr2's.....I think Bry has got it spot on, YOU need to do more research, I think you are reffering to the red mr2 which featured in max power many years ago, and it was THIS car that featured a customised exhaust (which I think is now available to the public anyway), it was a single exit exhaust. Why would you think Phoenix power would use an exhaust that wasn't gonna be sold to the public on their demo cars, do you not think that the point of a demo car is to advertise the products which you are going to sell!? Hears a hint go to the Phoenix Power website, I won't give you the address as i'm sure you already have it, what with all the research you've done

I have gone through several exhuast design's and so far i have come to the conclusion that a staight through with a very minimal restrictive backbox works well

Ha ha, well Sherlock thats very clever of you, but why did you need to test exhausts for that deduction?

I'll say it again it doesn't matter which exhaust you choose, the blitz or departure, either exhaust will be fine for most people's power goals.

Good luck with your T78 project, i'm sure you'll research it well

[John Rees]

Hi all, Phoenix power had a larger bore d2 and the back boxes were of minimal restriction design for 700hp, completly different to the normal d2 that they sell on the market.Do ur research, people will sell u anything quoting that its capable of this and that.

What is he on about
Sorry Xxxx but you really have made your self look silly here, its one thing pointing something out but if you want to really flame someone, (lets face it we all get things wrong), then you'd better make sure your talking straight.

Oh and as for doing research, you need to learn to spell first
Sorry for being blunt but if thats the way you want it

STEVE B stay in your that box

[shahid rashid]

[Bry]

Nice to see u guy's have done some research, But the process of exhaust gas flow is slightly complicated for some, i will explain as best as i can.
Take a 4 cylinder engine, gasses leave the ports at different intervals yes , creating pulses in the exhaust flow yes , the pulses travel through the exhaust manifold to the turbo, there the turbo creates a restriction which disturbs the pulse flow of the gasses.A pulse is hotter at its beggining when released from the ports and at the end it is colder.The drop in temperature in back of every pulse creates a vacuum which if maintianed pulls the previous pulse and so on.
After the turbo the exhaust gasses need to go back to the pulsating flow, if disturbed by reflection (the V in D2) and restriction, the temp in the back of the pulse will rise creating a less vacuum which will not pull the previous pulse efficiently.The restriction at an end of a exhaust multiply's at the beginning of one creating higher temp therefore restricting pulse flow and efficiency.The faster the gasses exit the less the gasses get trapped in the combustion chamber.
If u restrict the gasses and the temp rises, the gasses that get trapped in the combustion chambers in between cylinder cycles will decrease combustion efficiency and also can create pre-ignition. A exhaust needs to be efficient to expell gasses and raising the temp does not help.
I hope this helps . I have done many complicated tests on the exhausts to come to this conclusion. .I have some questions why on the D2 there is more gas flow on one side then the other and also why is the exhaust flow pressure more on one side then the other , is it a efficient exhaust.
About the 700hp D2, sorry i did not know they had released this for sale to the public, , i will get my hand on it soon to test it and see how it prooves efficient at 700hp.

As somebody once said" the best lie is one that's hidden between two truths" You're mixing fact with fiction,exhaust gas temperature is controlled by air/fuel mixture,ignition timing, and cam timing,the only way that an exhaust system can affect the gas temperature is by being a too larger diameter bore size which will cause too slower gas flow allowing the gases to cool.For all the research you've done,you failed to mention that if the pulses are slowed down this inturn will result in More torque created lower in the rev range.Exhaust technology is far from simple and I don't pretend to be an expert on the subject,but if ever I need lessons on the subject I'll do some research of my own and not listen to condescending fantasists on the net!

[shahid rashid]

[John Rees]

About the 700hp D2, sorry i did not know they had released this for sale to the public, , i will get my hand on it soon to test it and see how it prooves efficient at 700hp.

Your kidding right, thats going to take some saving on B&Q wages

Aren't you the guy who used Bry's engine pic as your own, you must work on the B&Q Bathroom section mainly the toilet isle. Maybe you test the efficiency of U bends all day

[shahid rashid]

Bry's pic was too tempting not to use and thats a compliment, i did say am sorry 2 bry , as for all this about B&Q were has all this come from , chill john, i will stop posting advise that affends some. , oh one other thing john u seem to know alot about B&Q toilets and bends which tells me u must spend alot of time digesting in the toilets. .