Things to know for installing new exhaust?

Well, on thursday me and a buddy are going to be installing the new exhaust on my 1990 LX. We're putting in BBK unequal shorties, BBK O/R H-pipe, and Flowmaster A/T catback. I've already got a good set of copper header gaskets for the header install, and some spark plug loom to make sure that the wires will be out of the way of the new headers. Is there anything to check while this stuff is off, I'm thinking check o2 sensors for sure, anything else? After the install, what type of testing/break in should be done? I think I've read that having no cats will effect the computer right after the install, is this true? Any advice/tips from you guys is appreciated, or if you have a good site or 2, post em up here.
 
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Give the computer several hours to readjust (a few days driving). Maybe the O2 sensors are still good, I know they are expensive, don't worry if you dont have a MIL now. Enjoy em..
 
crazy_canuck999 said:
Well, on thursday me and a buddy are going to be installing the new exhaust on my 1990 LX. We're putting in BBK unequal shorties, BBK O/R H-pipe, and Flowmaster A/T catback. I've already got a good set of copper header gaskets for the header install, and some spark plug loom to make sure that the wires will be out of the way of the new headers. Is there anything to check while this stuff is off, I'm thinking check o2 sensors for sure, anything else? After the install, what type of testing/break in should be done? I think I've read that having no cats will effect the computer right after the install, is this true? Any advice/tips from you guys is appreciated, or if you have a good site or 2, post em up here.
no cats wont effect the computer because you only have 2 cats and 2 o2 sensors before the cats and the comp wont know but other than that make sure you scrape the block with a razor to get the carbon and junk off of it first or you wont get a flat surface and have a exhaust leak.
 
Make sure you have a couple of socket extensions, one of those swivel things for the socket to get at the header/h-pipe connection. If you can lube all the bolts and hangers with some good penetrating oil a day before the install it will save a lot of time. if you are not going to use your current cat-back any longer, cut off the pipes just over the axle for easier removal. You'll probably need a hacksaw for the metal tube the goes to the H-pipe from the smog system. Label your spark plug wires, when you remove them to make your life easier. you may need to remove the spark plug on the drivers side closest to the firewall. And you may have to remove your dipstick.

PM me if you have any other questions
 
they all use studs and nuts. use a very long extension with 3/4 in socket and take them out. you will need a uni-wiggle for at least one of them but if you are slick, you can get away without needing one. i know i didnt need one.
 
Be prepared to replace the rubber pucks. If they are the original ones they may be toast. Most parts stores wont have those rubber hangers but a muffler or mustang speed shop should. In any case, it may require some persuasion to get them onto the new stuff and I recommend some oil in the holes. If you are reusing the old stuff, you shouldnt have a problem but better get new so the exhaust sits tighter and closer to the undercarriage. Also, with any mod, give the computer some time to adjust. You may be disappointed with the results at first but once the comp figures it out, itll seem stronger.