downpipe install from hell
 

ok so i decided to be cheap and get the ebay dp for only $90. it came w/ a midpipe as well, but i cant use it b/c of emissions. im not really mechaniclly savvy but i figure its only six bolts, it cant take that long. hehe... i was wrong. 1 of the 4 bolts on the manifold was redicolusly hard to get to, the top bolt towards the back of the car. got the bottom two from under the car, using a wrench since a socket wouldnt fit. it only took about 500 turns moving about 2 inches each turn. the top bolt in the front of the car was the only 1 that was not that hard. (thanks to pb blaster) however this last bolt did not want to come out. couldnt be reached w/ a wrench or regular socket. i didnt have deep sockets so i had to use an extension, but the extension was so long that the socket wrench was aginst the side of the body. needless to say, that bolt took a while as well. then on the the cat bolts. i almost knocked my car off the jackstands trying to get those bastards off. rust sux! finally i was able to pull the precat out by this time it was dark, so i had to wait until the next day to finish. after my 6hrs of hard work, i went out and had a few drinks, and ended up getting trashed and not waking up until 3pm. :dammit: btw my car is at my parents house (which is 1 hr. away) b/c my stupid apartment wont let me work on my car in the parking lot. get there around 5pm and its getting close to dark. get the dp up under the car, and try to start lining up the bolts. i get 1 lower 1 in, but cant get the other. then i tryed taking the bottom 1 out, and starting from the top. then i couldnt get the bottom ones in. the mother f-ing holes are not lining up. its dark now, and i have to wait another day, but i have to work also. i get up earily to work on it before work, i whip out the dremel and start working on one of the holes. finally after 2 hrs of dremeling i get the bolts to line up. but i cant get a bolt on the last hole thats up top. so i tighten 3 of them but i now discover that the bolts that came w/ the dp are to long for the holes in the manifold. WTF!! i said screw it and just tightened them as far theyed go. back to the cat bolts. apparently the bolts on the dp are only ment to fit the damn midpipe. out comes the dremel again. 3hrs later i have the dp on the cat. i didnt have anymore time b/c i had to go to work, so i decided to crank it and see what happens. i now have a huge exhaust leak by the manifold. so i have to wait until tomm to get shorter bolts and hope i can somehow get the 4th bolt on. i may have to remove the abs or the y-pipe to get to it though. i cant wait to see what problems i run into tomm.

That's why the M2 is rated best because it fits. Pettit comes with new replacement bolts. Tri-point is supposed to work well. All of those are $300-$400. You are also supposed to replace the gaskey and the crush nuts. There's tons of horror stories uncluding one guy that paid $1k because of broken studs.

Damn sounds like a bitch, I hope I don’t have that many problems with my dp, that will be here on Wednesday.

I learned the hard way that it's better to buy used name brand dp (Pettit, M2, Bonez, etc) than a new cheap ass knock-off.

Do not overtighten the bolts going into the housing. You will either snap them off or crack the housing.

I ended up with a used Bonez DP and was able to use the factory studs for 3 of the 4 holes. The 4th hole required an M10x1.5" socket head allen bolt that was 25mm long.

Sonny

hope you didnt get the one of ebay. i agree w/ sonny, i wish i would of spent the extra money and saved probablly 2 days of work.

I've heard of fitment problems with almost all downpipes at one time or another...I was amazed how easy my stock precat came out, the bolts were easy to access about a 10 min soak with pblaster. Did you remove the heat shield for the abs? I don't have many tools at all...but everything went smooth for me...good luck! :)

SNracing, did you buy brand new gaskets, or did you reuse the old ones?

Also, which direction did the holes need to be ground out? Further out from the center, or closer to the center? I'm assuming you're referring to these holes: https://www.rx7club.com/attachment.p...postid=2757342

-s-

i had to drill outwards, and a little upwards on one side. and yea, its the holes on the flange that bolts up to the cat.

my buddies bolted up fine. He uses the dp and i bought the mp. It is a bitch due to the bolts being old and soaked in heat for so many years......Soak them all in PB Blatser wait 15 minutes do it again...Honestly when I couldnt get of the manifold bolts out I would spray them...drink a beer...spray them..drink a beer..spray them..drink a beer...By then I was tanked and they were loose.. SWEET

Yeah its and Ebayer, I already had a midpipe from ebay (bolted on fine). Then I saw this DP/MP combo for $100, so I said why not. I am gonna sell the MP to my buddy for $65, hes got an HKS DP. I will post after the install and tell how it went. I hope I don’t need a new gasket. And I hope that the bolts come off ez, its only been 16k sense I have had them off.

Another prob. with these is that the faces of the mating flanges are usually cucumbered due to the welding heat and they are not reskimmed flat....Leaks galore.

BTW SNracing we've all been there or are there right now,you are not alone.

I like your story man it made me laugh....sorry.It's like "what now!" with every next step....I wanted to burn my car many a time.

I have that MP/DP and an HKS catback and it fits perfectly, the only problem I had was the flange on the dp I had to grind a little of the weld.

I just did a motor rebuild... so my engine isnt a v.irgin anymore.. :) hopefully next month when I do my DP..it wont be too bad either.... of course imma get a M2.. if they are still around... :(

snracing check your pm's

That sux, I got the "hks" dp off ebay for 120.00, bolted right up.

Why did'nt you use the original studs? Am I missing something?

your not suppose to use the original nuts.

the nuts are crushed at one end so they won't vibe off.

(also says in the FSM in big bold letters)

They usually take the stud out when you remove them.

You can get replacement studs/bolts at a auto shop.

most exhaust components are naughty.

Prolly didn't help to use the wrong bolts too :)

Even if the stud comes out (two of mine did) they screw right back in??

is that a question or a statement?

-sometimes they do

the ebay dp is definatly not ment to bolt up the stock cat, but i bet the mp would fit fine. i had to dremel out about a total of 2cm to get it to fit onto the cat. 2cm doesnt sound like a lot, but when your drilling out stainless steel with a tool that can barely handle ss, it sux!

actually im still there... i had some time to work on it again yesterday but still having problems. the bolts that the dp came with were too long for the threads in the manifold, which i thought was causing my leak. so i go to get shorter bolts to try and fix the problem. got the old ones out and new 1's in, put everything back together and started her up.... same F-N thing! i still have an exhaust leak at the manifold. a friend of mine is a mechanic for Mercedies (sp) so hes gonna take it up to his work where he has a lift, (much better than working under jackstands) and figure wtf is going on. hopefully my car will be back on the road by the end of the week.

pm's checked ;)

with the hks pipe, i think you are able to fit the dp over the studs since it has the small bend at the top of the pipe. with the pipes that do not have a bend in them, you have to take the studs out. and with my wonderful luck that i have, i stripped the original bolts.

ITS DONE! my friend took it to the dealership where he works, and fixed the exhaust leak. apparently the bolts that i got for it were to long as well. he put shorter 1's in, and it sealed right up.

man it sounds good! dp cleared up the exhaust path so the twins can sing. i cant really notice a diffrence in performance on the butt dyno, but its also about 90 degrees outside right now.

Wow...what a story. I too was considering buying a downpipe off ebay, because i figured a pipe was a pipe. Glad I read this before I bought it. I think now I'll come up with the extra cash and buy a brand from the rx7 store, or buy a used brand name off ebay.

Good to here that all is well now with your 7...

ok, so, i have to rub it in :) i paid my mechanic like $150 to put mine on... took them almost 7hours... took me like 30 minutes to drop off the car, pick it up again and pay :) it works perfect. the only thing i had to do was have the shop boys at work slot the cat-side holes .1" out from the center on each side so it would match right up.

This is a true statement. I used an expensive Bonez down pipe from good shop, before I went single turbo. It was a bitch and I never got one bolt holes to line up right. I eventually had to make one of the bolt holes bigger.
The mid pipe on my car is off e-bay and it looks and fits great.

Brady Mahoney