No exhaust???

[mudbog42]

Ok I have a buddy who just torched his exhaust off and is now running just headers.

I know this is bad and I think can burn up your valves because the scavenging effect is not there but if you ran just straight pipes you would be fine I think

Somebody school me on this so I can explain to him why he should fix that

 

[beater_k20]

the scavenging effect takes place in the collector of the header, so he should be fine. as for burning the valves, i run a set of 24" individual tube headers, and my buddies run some shorter than that on derby engines. never had a burnt valve with them, and they get WAY hotter than an engine in any other application.

 

[mudbog42]

So there should be nothing to worry about??? Also don't know if it makes a difference but its a 98 tahoe, 5.7 vortech with the stock exhaust manifolds

 

[beater_k20]

so he's not running headers... how much pipe does he have left after the manifolds? if its less than a foot, he very well may have problems. not to mention the o2 sensors will get messed up readings.

 

[mudbog42]

Yeah my fault I should have made that correction but as for the cut it is right after the sensors so there is not very much pipe there

 

[Eric M.]

So there should be nothing to worry about???

Nothing other than losing your hearing and becoming best friends with every cop in town!

Eric M.

 

[trailblazr81]

And sucking those fumes!!!

 

[beater_k20]

the sensors wont get a correct reading because they wont be able to accurately judge the a/f mixture. it'll normally run rich when that happens. and with manifolds, the scavenge effect is virtually non-existant.

 

[blazinzuk]

i have been running open exhaust for a while now, not entirely by choice. I don't put very many miles on my truck but I did make the trek to Moab UT. about 500 miles one way with no ill effects at all. Of course this is on a 73 blazer with your basic headman headers and some turndowns