Has anyone performed a Downpipe install on their FD?. If so, how hard/easy was it and how long did the install take?. Any tips for a smooth job? Was there a noticable HP gain? And did the exhaust loudness significantly increase? Your anticipated advise and opiniions are much appreciated.!!

 

Just soak everything down really good with PB Blaster before hand. As long as you don't break a stud, it should only take a couple hours.

 

i did it with a friend's help sometime last year. It's not too hard but it's good to have someone help remove the stock precat once you have the bolts off. We had to push the engine around a little to get it out. Use WD40 or something to help loosen the bolts beforehand. I remember having to reach my hand down there and take off the bolts like a 1/4 turn at a time so its a pain and just takes a little time. It took us a few hours to do it because of the time required to take the bolts off and other little things. People say it can be done in an hour but really the only thing that ever took an hour or less is putting the front strut bar on. Granted, i work slow but to do a downpipe install in an hour, i think someone would have to have done it like a dozen times already.
The exhaust sound changed a little bit. It wasnt really that much louder, maybe just a little.

 

It can take one hour or it can take a week, it all comes down to the bolts..
Soak, soak and soak!

 

Budget 1-2 days to get the job done, which allows for plenty of soaking. Get good tools and be patient. There are some good write ups, search around on the forum but the advices above are all good.

The most important thing is not to bust the nuts or else you'll need to remove the studs. If something is too tight, just soak some more and move the bolt back and force a little to loosen it.

The HKS DP is good bc it is easy to install and does not require stud removal. The M2 DP costs more but has a slightly better flow and is SS.

Either way, you'll notice a difference. DP gains about 15-20 hp so it's one of the best mods that has little trade off.

 

I just finished mine yesterday. The biggest problems I had were the bracket that holds the dp up to the chassis. The bolts were so rusted I couldn't get a ratchet on them. I had to use a Dremel and cut the bracket. Then I went to install the HKS and was going to bend the bracket around the pipe and clamp it to hold it there. Bad idea, I wrapped my dp in exhaust header wrap and there isn't enough clearance and it got stuck. Back with the Dremel to cut the whole bracket off. It isn'r really needed anyway. The other problem I had was putting the top rear nut back on the stud. It took me like 30 minutes to get the stupid thing to thread on the stud. Other than those two things it wasn't too bad. I soaked the nuts once in the morning and then again at night and then went at them the next morning. Good luck!!

 

Be sure to use anti-seize lubricant on the threads when you install the DP...

Also, might be a good idea to get a couple of DP studs just in case one breaks. Better to have them available, since Murphy's law will mean the old ones won't break due to the presence of the new pieces.

 

Great advice guys. Thanks to all who took the time to get involved. I'll probably get my DP early next week and will do the install before next Friday. I'll do a thread on "DP post-installation" which I hope will include good news on higher boost pattern change and notable HP gain.

 

I was lucky, my studs just un-screwed as I took off the pre cat. Everything else was in nice condition, a little PB Blaster REALLY worked. It was the first project I did on the FD. Had the pre cat off while it was still warm!

I have found that the studs that are used to hold the turbo to the exhaust manifold, which are a little shorter than the DP studs, allows you to slide the DP over the studs easier. Mine was a Pettit SS by the way.

Now I can hear that nice whistling sound as the turbo spools. Cool!

 

I would take off the Y-pipe too. It takes a little more time but it makes it a lot easier to get to the nuts and saves a lot of frustration.

 

Two thoughts:
1) your boost pattern shouldn't change. You might notice higher peaks (like any flow mod), but that's not necessarily a good thing. More than 12psi at any time on stock equipment is bad.

2) Is it necessary to go back and re-tighten? I've been thinking about it (1000mi since I put mine on), but I can't understand why metal gaskets and new fasteners should need re-tightening. Anyone have the torque specs for both ends of the dp?

Dave