quick question on making a downpipe

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Crash33
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quick question on making a downpipe

Post by Crash33 »

I was going to go with the jgs downpipe because I have their manifold but I do have a Hobart 125 ez flux welder and I was reading about how even if the outlet on a turbo is 2.5 making a 3" is always better. So I wanted to ask, I have a garrett T3\60-1 with a four bolt exhaust housing, when making a downpipe do I need a reducer peice that goes 2.5-3" or is the normal exhaust flange big enough to just go 3" without it?

P.S where would you guys go to get the supplies?

Thanks
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
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Kfred
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Post by Kfred »

I know the 5bolt housing is big enough to just weld a 3" pipe to, but just barely. It would be best to have a smooth 2.5" to 3" transition though either way. Look up dimensions of the 4bolt housing and i'm sure you can find your answer.
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Post by godrifttoday »

Just go to a mufller shop an have it flare it from 2.5 to 3 inch... It's only a small section
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nelson240sx
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Post by nelson240sx »

the cheapest place i have found 3" piping is autozone unless you want to buy it in big sections (10+feet). THey have adaptors there too

-Nelson
KA24E-T 06/06 to 10/09 (T25 then H1C Holset) - sold
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Crash33
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Post by Crash33 »

Okay so I am still planning on making my own down pipe and I went to ATPturbo.com and saw that they now carry v-band adapters for the t31 exhaust housings .
http://www.atpturbo.com/mm5/merchant.mv ... e=ATP-FLS1
Do you guys think it would be easier to get this and than just get a v-band flange and do it that way it would make it easier to take off and such. I just want to get your guys opinion on it, I am running a jgs log mani so I think it should have enough room right?
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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TinyT
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Post by TinyT »

Crash33 wrote:Okay so I am still planning on making my own down pipe and I went to ATPturbo.com and saw that they now carry v-band adapters for the t31 exhaust housings .
http://www.atpturbo.com/mm5/merchant.mv ... e=ATP-FLS1
Do you guys think it would be easier to get this and than just get a v-band flange and do it that way it would make it easier to take off and such. I just want to get your guys opinion on it, I am running a jgs log mani so I think it should have enough room right?
ya do it that way for sure, v bands are gods gift to pipe coupling
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Crash33
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Post by Crash33 »

Yeah I thought it would make as a better option rather than to just go for the straight bolt-on. Makes it a hell of alot easier to take off too.
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
blacks13coupe
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Post by blacks13coupe »

Unless you are trying to make it stainless, check out this piece. I also have a 2.5 outlet and made the reducer as soon as it exits the turbo. It transitions pretty smooth and very quickly for tight fitment.

http://www.summitracing.com/parts/WLK-41973/
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Post by Crash33 »

Alright so I will be ordering my stuff this coming week. So I really want some info on someone who has used this adapter or something close did it take up a lot of space or was it okay? I am running a jgs mani so the turbo will be set forward more than the other manifolds around. I really want to make it easy to remove that is the nice part about it. Also who many bend pieces should I get, I was thinking two 180 bends, or should I get more?

Thanks
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
shwag
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Post by shwag »

If your only making a downpipe, you only need two 90s, not even.
The radius of them is more important, however.
You wanna keep things pretty tight on the first bend down, then the next bend that rides the floor pan can be a tad wider.

I would add a small flex section while your there.
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Crash33
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Post by Crash33 »

Alright how long of a flex pipe should I get?
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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Post by shwag »

Crash33 wrote:Alright how long of a flex pipe should I get?
It doesn't matter really. Whatever you can fit.
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Post by Crash33 »

Alright where is the cheapest place to buy I see amazon or ebay. Would you guys recommend either?
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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Post by n97240 »

Ive always ordered my bends and supplies from these guys.

http://www.mandrel-bends.com/catalog/
I no longer have a ka actually in a car. Do the 2 ka's sitting in my garage qualify me to be on this sight?
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Post by Crash33 »

I know this is getting old but I plan on getting my down pipe made before school starts. I looked at the site that n97240 posted and I will probably go with them, now my main thing is I have a jgs mani and I saw that they don't have reducers but they have a transition cone that I think would work, I also will get a flex section as well. Do you guys think there is enough room to go from a small section of 2.5", say maybe 3-4" long, to 3" piping for the rest or should I put 2.5" until I get passed the steering shaft or something? I think it is a little tight but not sure if it could work or not.

thanks in advance
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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Kfred
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Post by Kfred »

Crash33 wrote:I know this is getting old but I plan on getting my down pipe made before school starts. I looked at the site that n97240 posted and I will probably go with them, now my main thing is I have a jgs mani and I saw that they don't have reducers but they have a transition cone that I think would work, I also will get a flex section as well. Do you guys think there is enough room to go from a small section of 2.5", say maybe 3-4" long, to 3" piping for the rest or should I put 2.5" until I get passed the steering shaft or something? I think it is a little tight but not sure if it could work or not.

thanks in advance
Cone from 2.5" to 3" right off the turbo. there is plenty of room for a 3" downpipe.
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Post by sdaigle240 »

yup, those guys are good, i got this exact one, and jumped to the 3" right off the housing
http://www.mandrel-bends.com/catalog/tr ... e-681.html
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Post by sdaigle240 »

I'm no pro, Was my first time too. Here's some pics for ideas.

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airman wrote:I'm all about spreadsheets. Bitches love spreadsheets.
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Post by blacks13coupe »

Doesn't look bad at all. The recirc of the wastegate seemed to be the hardest part to me.
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Post by Crash33 »

Alright cool thanks.
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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Post by denise »

I want to replace mine but I have several issues with measurement and how to fix the new pipe can anyone who has done this before help me with this information. I really need to fix this as quickly as possible.
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Post by TinyT »

denise wrote:I want to replace mine but I have several issues with measurement and how to fix the new pipe can anyone who has done this before help me with this information. I really need to fix this as quickly as possible.
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Post by sdaigle240 »

I can't bake your cookies unless u tell me what kind u like.

No info in, no info out. And it says ur an inventor!?!?!?



Ps for the love of god, use v bands. My retrospective fail.
airman wrote:I'm all about spreadsheets. Bitches love spreadsheets.
schmauster920 wrote:I shall cast my own pistons in the sands of time, then forge them in the depths of hell.. as funds allow
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Post by Crash33 »

Alright so here is the update on vacation so yeah gotta do it. What do you guys think of clearence?
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The first one I did adjust so it is more in the middle now, but it is the MC I am asking about.

Thanks
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
blacks13coupe
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Post by blacks13coupe »

You have more clearance than I do. Just make sure you wrap it and address heating.
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Crash33
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Post by Crash33 »

Alright cool I post a pic of the full mock up just tack welded. I gotta say I havn't wleded in a while or done any real stuff for my turbo porject, but it felt good to make something lol.
1993 240sx fastback FINALLY TURBOED!!!!
T3\60-1
JGS LOG MANI
740CC INJ.
NISTUNE
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