exhaust size

[lighty01]

ey pplz,
thought id toss all u professionals a questions. im thinking of getting a full zorst to add a lil power to my slowmobile.. i got a civic gl... engine is d15b4.. just wondering what size would be the best.. i have cold air intake as well.. any help would be great

[egSi]

id chuck on a 2" at most and maybe that is even a lil too big. whats the output on ur engine?!?

[tRipitaka]

how did ya get the cai on ur carby ?

[J-MuN]

Search :)

Try here (http://www.ozhonda.com/forum/showthread.php?t=8351), tells you basically wat size for what type of engine :thumbsup:

[Sitwy]

I believe 2" would be the best size for sohc under 1.6L

[hoonda]

I believe 2" would be the best size for sohc under 1.6L

^^i agree

[J-MuN]

The best exhaust diameter for your car really depends on how many modifications have already been done and also the desired outcome and/or application.

I won't bother delving into which headers are best to get for your car because there is a lot of argument as to which is 'best' header. Search the forums for more info on headers.

Here is a rough guide as to exhaust piping diameters for common Honda engine capacities.

NOTE: The following is only a rough guide and is in no way appicable to all cars

Non-VTEC
1600cc - 2 Inch
1800cc - 2 or 2.25 Inch
2200cc - 2.25 Inch

DOHC VTEC
1600cc - 2.25 Inch
1800cc - 2.25 or 2.5 Inch
2200cc - 2.25 or 2.5 Inch


*All values are internal diameter.

The second set of values given are if you are after a strong top end however it should be said that you will be sacrificing low RPM torque as a result. Most exhaust shops will advise you of the lower value to give you a good spread or power throughout the rev range, but if you are after good power for race situations, I would advise going for the second set of values.

The key is to have the same diameter throughout the system from the collector all the way to the muffler for optimal performance. There is a common saying "A chain is only as good as its weakest link" and the same applies here in terms of keeping a constant diameter piping all the way through.

[dc2dc2dc2]

i think save ur money and do something else. Adding a 2" exhaust isn't gonna all of a sudden turn ur car into a rocket. It just feels faster due to the noise, simple as that.
SAVE UR MONEY AND DO SOMETHING BETTER WITH IT !

my 2c.

[Sitwy]

Good post :wave:

[lighty01]

i just got a pipe running from the bumpa to my carbs.. buh a mate was talking about some ram flo thing.. he says its ment to be betta...
so 2" is max.. thanx ppls..

[PAPZ]

2 and a quarter is a good size to go for top end, mayb 2 and a half for mid range, but can lose a little top end power... i think from waht i remember.

[Sitwy]

I think if the exhaust go too big , it will loss the back pressure. and then is just like you can hear the exhaust sound but the car not moving...^.^

[tRipitaka]

I think if the exhaust go too big , it will loss the back pressure. and then is just like you can hear the exhaust sound but the car not moving...^.^
another backpressure statement.. :rolleyes:

[panda[cRx]]

i think save ur money and do something else. Adding a 2" exhaust isn't gonna all of a sudden turn ur car into a rocket. It just feels faster due to the noise, simple as that.
SAVE UR MONEY AND DO SOMETHING BETTER WITH IT !

my 2c.

i agree man but if you have already made up your mind about doing it don't go any larger than 2"

[CIVIX]

Yeah go 2" either press or mandrel bent. Although going mandrel isn't going to make too much of a difference...

[pgclee]

1.75"-2.00"

[_FeRiO_]

I have a D15b myself, i had this same debate. In the end i went 2.25, which found was bit loud, but it went alright.

[TKO]

Well, i had installed a 2.25" pipe for my D16Y1 EG5. And i find it leak toque badly from 0-3500rpm. At those rev, the car just feel like not responing to the push in gas. Worst if you change gear in those rev. It feel like take a while for the car to get going again.

But once it pass about 4000rpm, the ground speed & engine speed dose go up quicker.

But Most of my time is driving in the 2500-4000rpm range so that slow feeling really kill me. Me is changing to a 2" pipe soon (When i have the money) & hopefully it will be better.

Got me think reading the above forum, should i do 2" or 1.75"?

[mugeneration]

maybe wyn's post (quoted by J-Mun) should be made a sticky? People always ask this stuff.

[lighty01]

maybe wyn's post (quoted by J-Mun) should be made a sticky? People always ask this stuff.
dats a good idea..
ohh.. and saving up for engine coversion is outa the question.. i dun have that sort of money.. if there are any better mods for around $350 feel free to lemme know