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Hmm, then i've always understood it wrongly.
I do know a to big exhaust size is bad, that why we kept the original size of the M3 exhaust.
But i always thought that an NA engine always needed some kind of back pressure and a on a turbo engine it wasn't such a big deal.

Thanks anyway, learned something again

We just need to reduce the sound and kept with 60mm inner diameter
how i understand it is with too small of an exhaust the exhaust doesnt flow out of the engine fast enough, and this is obviously bad.

with too big of an exhaust there isnt enough back pressure, and this reduces compression.

how far off is this?
Quote from Scrabby :Hmm, then i've always understood it wrongly.
I do know a to big exhaust size is bad, that why we kept the original size of the M3 exhaust.
But i always thought that an NA engine always needed some kind of back pressure and a on a turbo engine it wasn't such a big deal.

Thanks anyway, learned something again

We just need to reduce the sound and kept with 60mm inner diameter

Yeah if you need to reduce sound I think best solution is a decent straight thru muffler. They basically dont add any or just very little back pressure because the pipe shape and size is still kept the same.

Quote from logitekg25 :how i understand it is with too small of an exhaust the exhaust doesnt flow out of the engine fast enough, and this is obviously bad.

with too big of an exhaust there isnt enough back pressure, and this reduces compression.

how far off is this?

Exhaust back pressure wont add any compression to the engine.
Reason why you don't want too big exhaust is that a big exhaust adds pressure vs correct size kinda makes it's own "suction".

http://www.thumpertalk.com/top ... st-backpressure-the-myth/

I used to think that back pressure was needed also some time ago, but didn't understand why it would be. Remember reading a short note about the exhaust sizing and how it is supposed to keep the velocity of exhaust gases at reasonable speed and it suddenly all made sense.
wow very simple and makes plenty of sense, how hard is it to match these values? i havent gone exhaust shopping yet.

does the manufacturer tend to find the best size, or can it usually be improved on?
Resquiat in pacem
i have just came back from video making. And of course i got a mustang to race with,who i left in dust. +outside video for awesome sound preview ! coming tonight !

UPDATE: outside vid : http://www.youtube.com/watch?v ... jxRg&feature=youtu.be
Quote from e2mustang :i have just came back from video making. And of course i got a mustang to race with,who i left in dust. +outside video for awesome sound preview ! coming tonight !

UPDATE: outside vid : http://www.youtube.com/watch?v ... jxRg&feature=youtu.be

might have already asked, but i forget


what is your opinion on a CDV delete? i havent done it yet, but i have gotten quite used to the CDV in my e39, its only a 528 so its not like the raw power is going to kill the slow moving clutch... should i go for it, or not bother?
Quote from logitekg25 :might have already asked, but i forget


what is your opinion on a CDV delete? i havent done it yet, but i have gotten quite used to the CDV in my e39, its only a 528 so its not like the raw power is going to kill the slow moving clutch... should i go for it, or not bother?

I havent done many cars,but i didnt feel much of a difference. it was an e46. I know on E36 M3's they change slave cylinder to a 325 one (like on mine) and they get very hard.thats what she said !
my left leg is twice the size of the right one XD
some say its an extreme difference, some say its hardly noticable...probably depends on how far gone your clutch is.

i think i will just go for it, its a 15 minute job thats reversible; might as well.
yes but once u open up the line you'll have to bleed it,if u dont ur F-ed. and sometimes for some reason it wont bleed,and it becomes a headache
My new (to me) n/a mr2 daily driver.



Quote from e2mustang :yes but once u open up the line you'll have to bleed it,if u dont ur F-ed. and sometimes for some reason it wont bleed,and it becomes a headache

why doesnt it bleed? i thought that would be one of the simpler things that you could do to a car - bleed a clutch.

and LOL to thats what she said
sometimes the easyest things dont go smooth.thats what i learned in almost a decade of working on bmws. Especially do not work on cars on mondays and fridays ! never forget that !
hahaha you never do anything those days anyways

no idea when i will get to do the delete, but dot3 or dot4 brake fluid good to top off the resovoir? one better then the other? marginal difference?
always dot4,it handles much higher temperatures
ok, and any idea why my heated seats dont work all of a sudden, light up then 3 seconds later shut off, the rest of the heating works (its off one fuse).

both sides, no matter what setting...the other fuse that is 'responsible' for heating stuff was not even there when i checked it, so i assume it is not the culprit.

pm me if you have an answer, this is derailed enough...figured i would ask an expert while i have his attention
electrical stuff could be very detailed,could have to dig deep but first i would put fuses where it says it should be.if that dont work i cant do much over the net.
Quote from logitekg25 :ok, and any idea why my heated seats dont work all of a sudden, light up then 3 seconds later shut off, the rest of the heating works (its off one fuse).

both sides, no matter what setting...the other fuse that is 'responsible' for heating stuff was not even there when i checked it, so i assume it is not the culprit.

pm me if you have an answer, this is derailed enough...figured i would ask an expert while i have his attention

i guess i didnt get that memo
nor the plane tickets
wasnt me!
Quote from e2mustang :electrical stuff could be very detailed,could have to dig deep but first i would put fuses where it says it should be.if that dont work i cant do much over the net.

thanks, i shall try that.
Quote from Fuse5 :i guess i didnt get that memo
nor the plane tickets
wasnt me!

...?
Quote from logitekg25 :wow very simple and makes plenty of sense, how hard is it to match these values? i havent gone exhaust shopping yet.

does the manufacturer tend to find the best size, or can it usually be improved on?

Some people go as far as build their exhaust systems and try different combos in dyno. But if you use any common sense you can't go that badly wrong. Every engine is unique (especially if you build your own one instead of using stock engines) so everyone of them has their own "perfect" exhaust size. Also the exhaust size depends on what RPM area you want it to be optimized. General rule is that bigger exhaust works better on higher RPMs.

I'm referring to a simple chart I found over the net a while ago:
170 - 240 hp = 2.25" - 2.5"
240 - 350 hp = 2.5" - 3.0"
350 - 500 hp = 3.0" - 3.5" or 2x2.5".
Don't take these numbers as a fact of the perfect exhaust size for your engine, but if you follow them it's probable that you will be able to avoid the worst over exaggerations.

I myself already know that I'm going to the 3" route for my next engine. But all I know about it that I won't be making a huge mistake and it should be ok for the spec I'm going.
Quote from logitekg25 :thanks, i shall try that.


...?

i think he refers to the part u said : the other fuse is responsible blabla..
hes name is fuse
Scrabby and e2mustang, those vids just gave me goose bumps, I have always loved the sound of R6 engine, I still think it's one of the best sounding engines of all.
Sold my bimmer, i will miss her sound.

At 2:17 and 10:05 you can hear her sing.

Video of me driving
Quote from BigPeBe :Some people go as far as build their exhaust systems and try different combos in dyno. But if you use any common sense you can't go that badly wrong. Every engine is unique (especially if you build your own one instead of using stock engines) so everyone of them has their own "perfect" exhaust size. Also the exhaust size depends on what RPM area you want it to be optimized. General rule is that bigger exhaust works better on higher RPMs.

I'm referring to a simple chart I found over the net a while ago:
170 - 240 hp = 2.25" - 2.5"
240 - 350 hp = 2.5" - 3.0"
350 - 500 hp = 3.0" - 3.5" or 2x2.5".
Don't take these numbers as a fact of the perfect exhaust size for your engine, but if you follow them it's probable that you will be able to avoid the worst over exaggerations.

I myself already know that I'm going to the 3" route for my next engine. But all I know about it that I won't be making a huge mistake and it should be ok for the spec I'm going.

Rpm ranges are more about Primary lengths on the manifold I thought? IE longer primarys = higher powerband, shorter primarys and longer secondarys = low power band/a bit less power but longer curve.
But yeah, the exahust dimensions seem about right, 1.75" primaries on a pinto are ok up to 200bhp!
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