| hoya |
| My muffler is out of service (pipe rusted through) ... I took the can off so it's not hanging and didn't have time to put it back on, so I've been driving all week without it. Friend of mine mentioned cold air could get into the engine and damage the valves, any truth to that? If so, I fail to see how this would not have effect while having a muffler too, especially catback exhaust since that's basically like having a straight pipe anyways. I could understand if this was directly at the exhaust manifold, but my exhaust pipe runs all the way to my rear wheel, well aways from the engine itself ... maybe I'm not educated enough ... again, the thing with the catback (are all these people driving around with catback exhaust damaging their cars then, since it is basically straight out exhaust like without a muffler? ... isn't it?) |
|
|
| Mekanik22 |
| Your friend is wrong. Cold air doesn't just magically crawl into your tail pipe and into your engine. Your completely fine unless, like you said, a manifold was cracked or something. I drove around for just about 3 months when I blew my muffler to pieces and I had no problems. It's fine man. |
|
|
| hoya |
awesome Mekanik22, thanks a lot for your reassurance ... maybe my friend misunderstood my ESL, or I misunderstood what he said =P
thanks again, i appreciate it. |
|
|
| Soulfly |
and even if the manifold was cracked.. I don't see how it would hurt anything at all..??
'cept for the loosing torque issue... ? |
|
|
| icydude |
is it myth that no back pressure on a n/a engine would be bad for the valves.
someone told methat once and i still dont know what to make of it.......as in no manifold at all. |
|
|
| Thegnome |
IMO, the difference in outside temperatures and your engine heads could be a problem.
Having the exhaust manifold intack would equalize pressure and temperature.
No manifold at all could cause severe strain or something... |
|
|
| Soulfly |
I could see the hot valves cooling fast could be a problem.. but then again.. The intake air is cold???
lol.. but I guess it's not cold as the -5 degrees we have now...
Hmm.. With No exhaust manifold AT ALL.. I could see it potentially posing a problem.. because of expansion and contraction... but even then.. it should still be fine.. a little burst of cold air couldn't cool it fast enough to crack valves.. or do SERIOUS damage.. that I can think of? |
|
|
| ozzmodan |
My Opinion:
Any exhaust leaks ahead of the O2 sensor(s) are something to be concerned about, especially in the exhaust manifold. An overly rich mixture caused by the inaccrate O2 reading, mixed with fresh air from a manifold crack, plus the heat/flame from the cylinder chamber under certain conditions will cause an afterburn which will try to equalize pressure through the exhaust, manifold crack & any open exhaust valves with less pressure than the manifold.
Watching a Mazdastar race a few months ago on Speed, they interviewed a driver that had a manifold crack during the race & he commented that he was lucky he was able to finish the race because the backfiring is extremely hard on the (rotary) engine, I'd assume a piston engine would be affected the same way?
Just my opinion, could be wrong.
Kyle |
|
|
| snugs |
| I remember hearing something similar, but basically it was the case if you had a car that was running zoomies or a open headers and left it outside to cool down on a really cold day you could wind up warping the exhaust valves, but if you've just got a hole in the muffler its probably doing more damage to your reputation than to your engine. :) |
|
|
| turbomike |
| drag, monster truck, jet boat, all run open headers it wont hurt anything |
|
|
| Soulfly |
Yeah 'ozzmodan's Post Made quite a bit of sence..
Although I was kind of just subtracting the o2 sensors and shit out.. But yeah.. That would make sence .. because the flame would shoot out the head.. and if it came in contact with cold air with more air particles.. then it would get more energy and shoot down the exhaust? causeing it to backfire.. thus putting some pressure on the exhaust valve...
But even still.. I don't see how that would cause much damage? |
|
|
| MX5 Miata Guy |
| I ran my Mazda RX-3 without a header once (it was a test fire to see if a particular engine would run...not on the road). Cool couple of minutes, as rotary engines still have combustion occurring in the header (no valve-train to absorb it), and as such, the right shock tower was bathed in flames. |
|
|
| snugs |
quote:
Originally posted by turbomike
drag, monster truck, jet boat, all run open headers it wont hurt anything
They don't exactly run those vehicles when its -20 out....
Now, what about drag snowmobiles? :dunno: |
|
|
| turbomike |
| 2 strokes are a whole different thing you need a big chaimber eg. a pipe to make power... |
|
|
| 180sxforthewin |
| Not all sleds are 2 stroke the new yamaha are 4 storke engines. |
|
|
| Nightstalker |
quote:
Originally posted by turbomike
drag, monster truck, jet boat, all run open headers it wont hurt anything
Those engines are also rebuilt after every race week end, if not more. Sure it might be fine for 15mins at a time.. But You could also run a honda engine for 15mins on a road course with no oil if you had to.. Its still not a good idea. Try taking the header off your shitty claimer car and run it for a while and see what happens. |
|
|
| flatboy |
| I've heard this story too, but it had to do with open exhaust on motorcycles. Cause some of those harleys run no mufflers and have short exhaust headers. A big wind bent my valves. I guess it could happen? |
|
|
|
