Suggestion about replacing downpipe..
 

Hi,

I was going to replace my down pipe on my 93 base rx7..

can someone give me some advice on how to take it off and install.. I have never done it and i heard its pretty difficult.. Should i use WD-40 etc.. and what to watch out for.. Some said something about some bolts.. I am getting a mild steel Down pipe.. I'm also going to get it Jet-Hot.. Do you think its good idea?? I would greatly appreciate your opioion.

PHIL

How many miles on the motor? If over 60k on motor, just wait and put on the down-pipe when the motor is replaced. If you do pull the motor, mount the down-pipe on the motor before its reinstalled.

Good Luck...

my car came with a downpipe, but the gasket between the downpipe and the turbine has blown, so it's LOUD as hell under the hood right now. I took a crack at it and it was NOT fun. probably going to be around 4 hours to deinstall and reinstall. It's easier on the American cars since you don't have a steering column to deal with.:eek:

DP/PRE-CAT Removal & Installation Suggestions
 

The best way to remove the pre-cat or downpipe is to work from under the vehicle. First remove the oxygen sensor and the sheet metal heat protectors near the connection to the exhaust manifold. There are two nuts that hold the pre-cat pipe to the main cat pipe. Loosen these nuts but wait until later to remove them. There "may or may not" be one additional bolt holding the pre-cat to the belly of the car. It is located about 8 inches from the junction to the main cat on the top side of the pre-cat pipe. If it is there go ahead and remove it.

The key thing to understand when removing the pre-cat or downpipe is that the STUDS that hold these pipes to the exhaust manifold MUST COME OUT before these pipes can be removed.

If the studs do not come out on their own when you turn the nuts that secure them, then:

First remove the nut entirely (this is an oversized nut),
Second obtain two normal sized nuts with the same threads and screw them BOTH onto the stud one at a time,
Third tighten the two nuts against each other,
Fourth put a wrench on the INNERMOST nut and turn the INNERMOST nut the direction to remove the nut. This INNERMOST nut is tight against the outer nut so the INNERMOST nut will not turn by itself and instead you will be turning the stud in the direction to remove it.

Exercise caution at all times and DO NOT EXERT EXCESSIVE FORCE to turn the nuts and/or studs. If too much force is required, then stop and use some Liquid Wrench to loosen things up before continuing. When reinstalling, again, take time to make sure the studs and nuts are inserted properly and not cross threaded.

Be patient and allow adequate time for this work and everything should go fine.

Liquid Wrench on all bolts at least overnight, precat and turbo studs. Soak the crap outta them till the fluid drip on the floor. You won't be sorry.

Thank you guys..

Luckily the DP hasn't been installed yet.. So, I just need to take the stock Pre-cat out.. WOW.. it seems like a job to me.. I will definitely take your advices on soaking the hell out of the thing night before and in the morning.. i think i'm going to wait until the weather here in cincy gets little bit warmer..

So, what do you think about the Jet Hot coating?? Should I do it since i already have the DP out??

Thanks!

PHIL

You're in a snow-belt state without a stainless-steel pipe(!), so you're behind the 8-ball as it is. Jet hot will help, but you can heat-wrap it as well.

I used to live in Cincinnati. It will be May before it gets warm there!

you should wrap the down pipe in some heat wrap, it does help! also do your self a favor and don't get the bonez downpipe. it is cheap and it is 3 inches but if you ever tried to put it on, the part that attaches to the turbos is pretty tight compared to the hks version which looks like the stock down pipe flang which gives you a little more room (what im talking about is where the bolts go it the turbo mainfold) its not impossible to use the bonez dp but it does suck!

Thanks..

At this point Jet Hot is a definite thing.. Some emailed me and they said wrapping is not so good idea?? I don't know.. I will think about it.. As for the Not getting a SS DP.. well, i first got an SS DP.. but I got screwed.. So, I ended up with the MILD steel one.. I haven't picked it up yet.. It will be this weekend (sunday).. The seller told me that it will have temp sensor hole.. I'm thinking about putting one on.. Any suggestion on that??

Thanks again.. I love this FORUM!!!

that hole
 

that hole is for your O2 sensor. Do yourself a favor and get a new one and install it in the DP before you install it. You can pick-up a new universal (Bosch) sensor from Napa for about $20

It's a supreme PITA. If you're not comfortable removing everything above the turbos, don't do it yourself. It's about a 3-4 hour job at a shop, so figure on paying $1-200 if you take it somewhere.

It goes much quicker with a buddy to help. The hardest part is getting the damn air ducts and clamps back on. Also those heat shields are razor-sharp.

Print this out and read it closely. It's very thorough.

Toadman,

Thank you for the link.. That's definitely going to help me.. I think a buddy of mine is going to help.. He's girlfriends father fixes Corvettes and races them.. So, he has all the little tools that he uses.. Hopefully, He wouldn't be offended by my car kicking his old corvette after my mods..

Thanks again everyone for taking time to post.. I greatly appreciate this!

PHIL

About the O2 Sensor... I guess any O2 will work?? Can someone recommend one that is good or excellent??

Thanks!

PHIL