stock rb26 flanges, help with DIY exhaust!!!

[David_NISMO]

I've seen how some of you have modified HKS or HKS style dump pipes to go around the Steering Column and frame rail. As opposed to going between the column and block like I did. I want to redo my exhaust like the first part. If I could track down the correct flange, I would rather build my own Dump Pipe.

As I recall the RB26 turbos use a 6 bolt flange as opposed to the 5 bolt flange like the 20/25. Am I correct? And where would I find a flange for such an application? Secondly, if I built my own dump pipe, is it worth it to try and go the divorced route? I've read at SAU that divorced setups don't do much unless you run the separate pipe atleast 16", that seems like a bit too far and hard for my experience. If I don't go divorced, what's the best way for collecting all of the gasses into a single pipe. I was thinking of taking a 3-4" pipe and hammering it into the shape of the flange, then reduce it immediately back down to 2.5 for the run to the Y pipe.

Any suggestions? I believe that my current setup is MORE restrictive than stock and that HAS GOT TO GO. Thanks

[David_NISMO]

FYI, Cut the front pipe flange off of one of these dump pipes and re-weld it at a different angle to go the long way around the steering column

http://cgi.ebay.com/ebaymotors...QrdZ1

It would appear that I'm right about the turbos using different flanges, just in the reverse. The rb20/25 uses a 6 bolt, where the 26 uses a 5 bolt

http://cgi.ebay.com/ebaymotors...QrdZ1

[gawdzilla]

your best bet is to buy those dumps pre-made. reason is b/c the front dump is already a tough fit with the rear compressor inlet pipe, and its tough to make from nothing but a flange. plus that 5 bolt flange is hard to find. it is gtr only.

next modify the front dump. hack off the 2 bolt end and weld tight radius stainless directly to it to get around the steering column. then re-weld on the 2 bolt flange you just cut off onto the end of your new dump extension.

last cut the front dump arm off of an aftermarket downpipe and shorten it so it will fit. its not easy but it can be done. i found this is the best way to do it instead of going between the steering column and the block. you can get a solid 2.75" through to the downpipe, then 3" from then on back or more.

[David_NISMO]

Sounds like the best way to go. I managed to build my own DP to go between the column and block. It took 4 mandrel bends, 2 straight pieces, inside of 6" to get it through, so going the other way around is going to be relatively easier.

Thanks for the info, I was considering building my own so I didn't have to mess with stainless and just go with mild, but you've made some good points to do otherwise.

What about the divorced issue, anything to worry about?

[gawdzilla]

divorced is up to you, mine happens to be divorced, but its not "necessary". all of those divorced pipes come together by the end of the dump flange anyway, so its a "stock replacement" on the gtr. when you route the exhaust this way, it doesnt affect using divorced or not.

[kouki munster]

gawdzilla, you wouldn't happen to have any pics of what you did to the dump pipe to get it around the column would you? I'm having a hard time visulaizing what you did, and in the last 2 nights of searching I havn't been able to find any pics.

[gawdzilla]

have a couple.. mail me