Cat replacement
- Thread starter g23.40sw
- Start date
R_Lefebvre
Expedition Leader
What info are you looking for? Exact fit options? High flow cat efficiency?
I use Random Tech cats on my cars. They're cheap, flow well and best of all very compact. But I haven't tried passing an emissions test yet, and I have heard it can be a bit of a problem.
I use Random Tech cats on my cars. They're cheap, flow well and best of all very compact. But I haven't tried passing an emissions test yet, and I have heard it can be a bit of a problem.
R_Lefebvre
Expedition Leader
pokeyYJ said:
I disagree. I can't think of many good reasons to NOT use a high flow cat. As long as you don't need to actually pass a sniffer test, they are cheap, compact, and improve both mile and power even if only a small amount.
True, modern cats don't restrict the exhaust near as much as the used to. But, a high flow cat restricts it even less.
Oxcart13
Observer
Too funny!! http://expeditionportal.com/forum/images/smilies/clapsmiley.gif
:clapsmile
:clapsmile
stevenmd
Expedition Leader
www.completeexhaust.com and have a local shop throw them in... no need for a high flow cat unless you have done EXTENSIVE aftermarket performance mods - which I doubt you have since the aluminum block can't handle the additional heat. A high flow cat does not create the necessary back pressure needed for your current engine to run properly. Plus, any supposed "gain" in power and mpg will be too minuscule for you to notice.:wavey: (1994 RRC LWB here myself)
bigreen505
Expedition Leader
:victory: Now I know for sure I have been around Graham too much. When I saw the title of the thread, "cat replacement," I thought you needed new door seals or something. I have been spending way too much time in the Rover section.
it is done!
It is done, thanks to all that gave input on this matter. I went with IMCO high flow cats and Magnaflow muffler. It has made a small but noticeable increase in power and an increase in MPG. So considering the $$ spent a worthwhile investment. Again thanks to all.
g23.40sw said:
It is done, thanks to all that gave input on this matter. I went with IMCO high flow cats and Magnaflow muffler. It has made a small but noticeable increase in power and an increase in MPG. So considering the $$ spent a worthwhile investment. Again thanks to all.
R_Lefebvre
Expedition Leader
That's a misconception. Engines don't need backpressure. They do need velocity tuning however.
pokeyYJ
Observer
R_Lefebvre said:
Ummm,,, I disagree. For proper combustion, and a clean running engine, a vehicle needs to have a properly designed exhaust system that provides the correct amount of back pressure and the correct scavaging (sp?) effect to clear the remaining burnt exhaust gas from the combustion chamber.
R_Lefebvre
Expedition Leader
Back pressure absolutely hinders scavenging. So which do you want? You can't have both.
A "properly tuned" means velocity tuned as I stated. It means an exhaust tuned to to flow adequately at higher rpm to reduce unwanted backpressure, while also being pulse tuned at the lower rpm range to aid scavenging.
Backpressure is never a desired trait, but only an unavoidable byproduct of a properly tuned system, thus the misconception.
A "properly tuned" means velocity tuned as I stated. It means an exhaust tuned to to flow adequately at higher rpm to reduce unwanted backpressure, while also being pulse tuned at the lower rpm range to aid scavenging.
Backpressure is never a desired trait, but only an unavoidable byproduct of a properly tuned system, thus the misconception.