bigger exaust pipes

[peterguzzi]

Hello guys,

 

I was in a workshop of guys who have a serious reputation here in the low lands and one of time told me to put 50 mm exaust pipes, from the head to the crossover!, on my centauro bases engine? But i always had understand that the bigger that pipe the more topspeed you would have?

And they are totaly into racing, they even build a diesel race bike, so i assume that they just thought i want top speed...

Witch i do'nt want...i want torque!

[Guest Nogbad]

Doubtful whether you would notice any difference at all given that most of the back pressure arises from the x over and cans.

[helicopterjim R.I.P.]

If you are looking for power for a 4V motor then check out the websites of Paul Minnaert and Zebulon or else try the Centauro Owners Group website. They have lots of tips and links to lots more tips. There is already good power in the 4V motor but lots more to be found whether you want torque, horsepower or both.

With regards to bigger pipes, by themselves they may not do much but in concert with other changes they are more suited for top end power.

Good luck whatever you do.

[al_roethlisberger]

...that and the fact that bigger pipes with the same exhaust outlet may have dubious value.

 

Keep in mind that exhausts are "tuned" and simply making the diameter of the exhaust piping larger can have unpredictable results, even reducing power if one isn't approaching the solution with a good base in understanding exhaust tuning.

 

I would say that you need to decide what your goal is, low, mid, high end power, torque... whatever, then go to a reputable exhaust builder, one that knows bikes and V-Twins in particular, and have them build the exhaust that will deliver to your goals.

 

As a general rule though, if you want the best power out the bike, equal length headers into a 2:1 collector system will probably result in the best bang for your buck. But in my opinion, a V-Twin should have dual exhausts, just for the auditory aesthetic alone

 

al

[TX REDNECK (R.I.P.)]

What works on your small block chevy also applies to your Guzzi . I have seen & read many dyno results where big tube headers kill low -end torque.

 

http://www.carcraft.com/techarticles/868/

 

 

 

 

One of the biggest mistakes made in exhaust-header application is the selection of primary tubes that are too large. Big primary tubes are only necessary to carry the gas volume generated at high engine speeds. Most headers with 1-1/2-inch primary tubes will carry an engine well into the 300hp range, while 1-5/8-inch headers can support up to 400 horsepower, and a little beyond in some cases. This depends a great deal on displacement and engine speed. It is usually better to err on the small side for a street engine so that torque remains strong. Pipes that are too large generally hurt the bottom end more than small pipes hurt the top end.

[peterguzzi]

Well..i hope that the picture i want to put here also comes here so you people can seen what's keeping me out of my sleep and that i have a long way befire i can fire her up!

 

 

[imgatt]

[peterguzzi]

As for the exausts...i have a crossover and believe that the original centauro headers would just be fine for my purpose...i want torque en pull power..cause i'm not mutch of a real driver who hangs next to his bike in corners...

The 50 mm headers looks rough but they are more for top speed....as i believe to have read here!

[TX REDNECK (R.I.P.)]

Well..i hope that the picture i want to put here also comes here so you people can seen what's keeping me out of my sleep and that i have a long way befire i can fire her up!

                                            [imgatt]

47954[/snapback]

 

 

What kind of sidecar are you going to run ?

[Skeeve]

Hello guys,

 

I was in a workshop of guys who have a serious reputation here in the low lands and one of time told me to put 50 mm exaust pipes, from the head to the crossover!, on my centauro bases engine? ...

Witch i do'nt want...i want torque!

47869[/snapback]

 

What's the x-sectional area of your 4V exhaust valves? Don't go bigger than that. [This is easier on the 2V motors, since all you have to do is measure the dia. of the exhaust valve & get the closest standard tubing size to match...]

 

That's my understanding of the standard protocols for figuring exhaust size. Whaddaya want for nothin'?

[jimbemotumbo]

Don't do it. TX is right. Big pipes, esp on a Vtwin will absolutely kill your torque. And unless you build a race motor, even that will have little to add to the top end.

[peterguzzi]

Don't do it. TX is right. Big pipes, esp on a Vtwin will absolutely kill your torque. And unless you build a race motor, even that will have little to add to the top end.

48404[/snapback]

 

 

Actualy that what my thoughts where as well....so i use the standard stainless frontpipes with a crossover....and a set of supertrapps....something the guy who knows all in my begintopic allso diaproof off...

Also a picture of my guzzi horror