Dreaded Exhaust Questions

[Grandma91quis]

I know this has been gone over a bagillion times. But im gonna get me some stock mustang shortys, and from what I have read my stock down pipe will not bolt up? is there anywhere I can buy some that fit my car and the stock mustang headers? I was going to ream the cones from the cats. Whats the easy way to go with this?

Also when installing a lokar shifter do i need to pull the tranny? If the lokar is gonna be a b%^ch whats a good cable shifter to get? Im also wanting to get a manual valve body any recommendations? Any usefull info on that would be helpfull thanks.

[Mr. Land Yacht]

personally, I wouldn't recommend the stock stang shorties...not worth the trouble...the BBK 1 5/8" shorties are much better. but they do cost more.
I have the stang shorties on my car and I don't think they do much for the sound or hp.
nice Merc, by the way! but, you could use some hubcaps/rims

[88Vic]

I've heard BBK unequal length headers are better for power. They do cost more than Mustang shorties though, but maybe you can find a set in a junkyard.

And the steelies look fine, just clean em and put wide whitewalls on em, that looks great. Just look at Boxman's 89, do it like his.

[91LTDProject]

I cant say for sure, but I think 1 5/8" is bigger than stock, and have read on many a website that unless you are improving airflow throughout the rest of the engine (intake, tb, heads, ect) going any bigger than the ports on the stock headers dosent do anything for performance, and no real gains will be seen. Stickin the mustang shortys on a stock lopo is more of a weight reduction, the shortys weigh nothin compared to the stock cast iron pieces, and I have heard you may see a bit of performance gain. As for the rest of the exhaust, there wont be any gains if you stick with stock diameter, and there would be no point to putting on the headers, but if you really wanted to, you could cut the flanges off and get 2.25" flanges welded on, but it would be better to spend the money and find a stock mustang H-pipe in my opinion.

[1987cp]

1-5/8" headers are said to actually cost power even on a stock HO motor, and factory '86-'93 Mustang bits flow better than cast iron, install easily, and can be had for a song. However, aftermarket 1.5" shorties can be had that will sound and perform a little better while still being fairly easy to install.

Female ball flanges from Walker (PN 41724 for 2", 41725 for 2.25", 41726 for 2.5") should adapt your stock cat pipes to any Mustang shorty header if you want to leave the rest of your exhaust intact - you just have to relocate the O2 sensors, which a muffler shop or a buddy with a welder should be able to help with. Obviously, beyond that it's a simple step to replace the cat pipes with anything you like.

Both my cars are using aftermarket Mustang crossover pipes and intermediate pipes, which do basically fit. The Summit H-pipe was easy to install, but the Pacesetter X-pipe shown below took a little finagling and still could be prettier. Some brands also offer Mustang crossovers in 2.25" diameter, which is theoretically better until you're making actual power.