Engine backfires!!

[peterbilt]

What kind of info would you need to make one ?

 

[cumminsbayou4x4]

never mind i have the same motor in my parts pile i could make one using that motor if you want me to make you one

 

[peterbilt]

Hell yeah that would be AWESOME , would it have a spark arestor on it? Just let me know how much I owe ya for time and effort.

 

[cumminsbayou4x4]

no i wouldn't put a spark arrestor just a straight pipe i could buy one for it if you want .how long do you want it to be? it won't hit nothing if its to long? i may can make you one this week end my foot had stitches in it and still anit got better yet so this week end or next week end

 

[devino246]

i may can make you one this week end my foot had stitches in it and still anit got better yet so this week end or next week end

That's what happens when you walk around barefoot all the time...

 

[cumminsbayou4x4]

i now realize it yall tried to warn me about it i should have listened. I was driving my 1 wheel drive go kart on thanksgiving day and put my foot out to push off because the tire is all the time spinning. well the kart takes off and i dont have time to pull my foot up so the back tire ran over it and my foot was cut on the sprocket.

 

[peterbilt]

Ouch! Holy crap man. Things coulda been a lot worse, but glad your ok. I'm in no real hurry for it so take your time to heal and do it in a couple weekends. I'm in the process I'd tearing the gokart part and gonna repaint it and build it up cool!

 

[cumminsbayou4x4]

thanks man yeah i could have broke my hole foot, i need to know do you want me to put some sort of muffler or spark arrestor on it and how long you want it

 

[peterbilt]

Yeah a muffler would be cool, I guess 3 or 4 maybe 5 inch pipe. With muffler
Here's a pics of what the *** looks like.

 

[GregMartin]

In general best performance would be achieved with a length of about 14" and an internal bore of about 3/4".

You need to match the suck with the blow. So unrestricted outlets have a negative effect if your intake is restricted. This is why people say you need back pressure. A longer header pipe will work better because it will provide a bit of back pressure.

 

[cumminsbayou4x4]

if it has a muffler one it that will give it back pressure so it doesn't matter how long the pipe will be

 

[GregMartin]

Depends how restrictive the muffler is. In any case my advice is free. Ignore it!

 

[devino246]

Backpressure is never advantageous in any IC engine. What is advantageous is the scavenging effect. Too short of a pipe, or too large of diameter, and that scavenging effect is null.

 

[cumminsbayou4x4]

i wasn't planning on making a really short pipe with a large diameter with the muffler im gonna use for him and the pipe it will have plenty of back preshure

 

[devino246]

it will have plenty of back preshure

 

[Doc Sprocket]

Nooooooo!!!!!! Dangit, people- Back pressure is BAD, mmmmkay?

 

[landuse]

The oooold back pressure debate

 

[devino246]

Do i need to prepare my scientifically backed anti-BS argument?

 

[cumminsbayou4x4]

i all was thought that a engine needs a little back pressure to run right and not to mess the valves up

 

[devino246]

i all was thought that a engine needs a little back pressure to run right and not to mess the valves up

Short answer: no, not at all. The people who say that understand internal combustion engines about as well as I understand the opposite sex (or really people in general, but that's a whole other topic).