hey guy just wondering if its safe to run open manifolds cuz i think my catalic is alredy messed up and it blocking the flow.Can anything get messed up if i do that?
Yeah, your pocketbook from all the tickets!!! Really, don't run open exhaust. It gets fumes in the passenger compartment, and the noise is uncomfortable and illegal to boot. Just my $.02 Earl
but i'm not running it on the street. Just that when i fire it up it seams like either the catalic or muffler is blocking the flow, and i want to check if they r still good or not.
Long running time with just open manifolds will over heat your valves and eventually burn them. You need to have some type of backpressure. just take the exhaust lose in front of the cat
do not disconnect the exhaust manifolds or headers from the heads and operate the engine..it will burn the valves...and could cause so real bad issues with the spark plug wires.....and the metal in the engine compartment.... if you want to run a straight pipe...disconnect the pipe from the catalytic convertor just in front of it... leave the manifold or headers on the engine...
go for it...it isnt that much louder than a glass pack....i had mine like that...the only prob...it is loud inside the car... due to resonating...and all that stuff you will need ear plugs to drive it
tanx guys 4 the info. Do u guys know some tips on how to check the muffler/converter? do i still need the converter if the car is smog exempt?should i just buy a new muffler and a piece of pipe?
I have heard that running without a significant amount of exhaust pipe, probably anything shorter than a header, will allow the valves to cool too quickly and warp. Any truth to this?
You are in CA. NC has tight restrictions on cat equipped cars in all the major metro counties. If it cam with a c/c, it had better have it and it gets an annual sniff test. I would guess that CA is more strict. Check that before eliminating the cat if you plan on going back to the street. If you have to have it scrounge around junkyards for a later model Ford with a motor similar in size. Perhaps you can use a c/c off of one of those cars. Maybe even use one with dual cats if you have a V8 yet. Seth
thats exactly what i said.....except disconnect it in front of the cat (cat = catalytic converter not car) He said he wasnt going to drive it on the road if you want to check the converter to see if its plugged start it up after dark and let it run for awhile...enough to heat up the exhaust really good and then look under the car, if your converter is plugged up it will be glowing cherry red just like you heated it with a torch scooper77515 you are correct, the valves will warp, the engine needs the back pressure to keep the heat uniform in the chambers otherwise you get erratic combustion in the chambers which cause your valve stems to bow
Grabber, you don't have to be formal around here...you can call me "scooper". We are all friends on this site. I always thought it was just cool air getting to them and causing them to cool too fast or unevenly causing the warp. Having a long hot tube (ie headers or pipes) makes it more difficult for cool air to get in, as opposed to a 6" long hot tube (ie exhaust manifold), which would allow cool air to rush in on those hot valves. I was thinking after you turned the engine off... When you are talking back pressure, do you mean this warp will occur while the engine is running?
