grandmas 89 marquis
 

Im down in chicago for college at UTI and my bro just got my grandmas 89 grand marquis MINT.90k . I wanna beef it up a little and maybe try and improve fuel economy. anyone got any ideas ?

cold air intake (you'll have to make it, there aren't any made for that car - check the intake threads) and dual exhaust. then drive it like a granny. real easy on the gas. It should make just over 20 on the highway that way... maybe more.

dual exhaust, cold air from ebay meant for a 1990-1993 Acura Integra, swap the upper intake to a HO one from a lincoln Mark 7 or compatible, have EGR spacer bored out, will have to find somebody to mod the throttlebody to be made compatible for the car, could change gears, do a tune-up, fuel filter, trans fluid and filter change...

my girlfriends 1989 Crown Vic normally averages 25mpg on the highway... still need to swap heads on her car to make it breathe easier and install her headers

ill be doing the exhaust and intake for sure. how much did it cost you to do the exhaust? and also i was wondering how much it would cost to cam it im havin trouble findin parts.

just did the convert to dual (stock style 2" pipes - replaced Y with H pipe and added driver side) for ~$325 at a local muffler shop. I had the original muffler replaced a while back after the original one exploded (that was a fun morning) and that was an additional ~$160. I have magnaflow mufflers on my car. here's a pic of the raw job:
https://www.mercuryforum.com/forum/p...5&pictureid=98

alright (sorry new to this) so if i wanted to just straight pipe from the cats i would need another cat and the H pipe and straight pipes? talk slowly :D

the catalytic convertors are located before the Y pipe. should just need to either find a H pipe at junkyard from Crown Vic, Town Car or Grand Marquis that has dual exhaust. i just got my stuff from junkyard and installed myself so i didnt have to pay. about the cam... i would get a cam for a 1997 Explorer since it is HO style to change firing order to treat the lower main bearings better, and have the torque still since these are heavy cars. when doing this, you should find a Lincoln Mark 7 ECM(brain, computer) to have the car fire the injectors correctly. mustang HO cam would work, but wouldnt have the pull off the line compared to a Explorer cam

autozone offers the H pipe and driver side tail pipe for about $70-80 together (search their site for exhaust pipe) if you can't find it in any junk yards. Just get a muffler to fit between the H and tail and you're good to go.

hmmm autozone you say.. ill give it a look . and as for junkyards there aint **** around here everything gets squished. i miss minnesota already :( thanks for the help guys

Is it true that you can use a mustang HO upper intake and just point it in the right direction for the MGM? From what I can tell, (searching for plenum gaskets) it's the same bolt pattern for thunderbirds, mustangs, mark 7s, vics and marquis.