Front Pipe Question

[bownstawkgtr]

I recently to went to a muffler shop to have a leak in my exhaust welded up. When I got it up on the hoist I noticed that the heat shield had chicken wire holding it together. After further inspection it was clear that the previous owner had bottomed out and partially crushed the front pipe. The GTR seems stock from the cat forward .
My question is whether I should find a used replacement front pipe, or go aftermarket. Right now I don't have plans for any major motor upgrades, but if the cost/gains of an aftermarket pipe make sense then that might be the way to go. Any info or help you guys have would be greatly appreciated.

[derk]

just get an aftermarket downpipe.

why waste time and effort to put in another pos stock one?

[DreadedFist]

Aftermarket. It'll improve the sound (if that's what you're looking for), and give you a boost in power (and who isnt look for that?) You can pick up aftermarket downpipes pretty cheap in the for sale section. Just make sure it's stainless :O

[bownstawkgtr]

That's what I thought. As far as installation, are they going to be direct fit?

[Skym]

Exhaust goes like this -

Dumppipe (x2 on GTR) > Frontpipe > Cat or Cat elimination pipe for racetrack use > catback exhaust.

If you are going to upgraded frontpipe, do dumppipes at the same time. Why, because some frontpipes (front of frontpipe + flange) match the smaller diameter stock dumppipes and make it difficult when upgrading dumppipes, as front of frontpipe is not compatible / too small diameter wise. If you do it this way you'll have to buy another frontpipe or modify the current frontpipe with new flange and front piece of frontpipe to work with upgraded dumppipes that are bigger in diameter.

With frontpipe you'll get a louder sound from exhaust, increase in boost level due to less restriction that leans out rich factory A/F ratio. That is what makes engine produce more hp. On some cars 0.1 bar (0.1bar x 14.7psi = roughly 1.47psi) increase in boost level is normal with frontpipe upgrade. With dumppipes, boost will rise again (roughly 0.08 bar).

[bownstawkgtr]

Thanks for the input , Seems like a good idea. Should I be looking for dumps and the front pipe from the same manufacturer in order to make sure they will work together. I've been doing some searching and there is a big difference in price between companies. I don't want to go overboard, but I don't want to skimp out either.

[mitch32]

Get a downpipe with a flexpipe and you should be fine. To remove the dumps is a job and a half. You should be ok with just a downpipe. Also if for some reason you end up wanting a stock downpipe I have one in good shape for sale (and I don't want much for it, I just want it out of my garage, lol).

[derk]

Thanks for the input , Seems like a good idea. Should I be looking for dumps and the front pipe from the same manufacturer in order to make sure they will work together. I've been doing some searching and there is a big difference in price between companies. I don't want to go overboard, but I don't want to skimp out either.

doesnt really have to be from the same company, as long as the ID of the dumps and downpipe are the same/ similar.

find used ones. save yourself a ton of cash over brand new ones, and its not like they wear out.. unless they were in a super low car and got scraped to hell.

i just sold my HKS one last month for like $150.

[Skym]

Secondhand is cheaper (as long as there is no rust on outside, etc if frontpipe is made of painted mild steel).

For new dumppipes, I like HPI (High Power Improvement) in Japan. Always hear about good hp gains from their dumppipes and don't rust after a period of time on car -

http://www.hpi.co.jp/products/exhaust/to/

Also HPI dumppipes into HKS frontpipe.

Another option is Tomei dumppipes, HKS 75mm equal length front pipes. Then into 90mm catback exhaust. Good for over 400awkw x 1.341 = 536.4awhp.

Also might be a good idea to invest in a boost controller to keep boost level lower (safe) with stock GTR ECU tune and is useful, as is part of what you buy when boosting engine up with stock turbo's. If not a boost controller, then Nistune for stock ECU to adjust ECU tune to suit increase in boost level.

[Marke]

Changing dump pipes is taking off the turbo's. Its a 8-10 hr job for someone that knows what they are doing.

Go aftermarket for you frontpipe. Good performance increase for the money.

[derk]

Changing dump pipes is taking off the turbo's. Its a 8-10 hr job for someone that DOESNT know what they are doing.

Go aftermarket for you frontpipe. Good performance increase for the money.

fixed it for you.

[bownstawkgtr]

I really appreciate everyones input, Don't know what I would do without this forum. I think I'm going to start with an AM front pipe. It looks like something I could handle myself. I simply don't have the time or space to be getting at the dumpies. Thanks again guys.

[mitch32]

If you want I have a spare downpipe (for cheap) that I actually want to get rid of. PM me if your interested.

The downpipe is easy to change just need some long extensions.