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Re: 2.5" Dump pipe for 4JB1T
Posted: Thu Apr 09, 2015 8:08 am
by geeves
Its going to cost half what adding the dump pipe will and you still get very usable gains. I cant give actual numbers though but my 2.8 bighorn ran a press bend 2.5 inch pipe from the flex pipe back and went very well.
Re: 2.5" Dump pipe for 4JB1T
Posted: Thu Apr 09, 2015 5:06 pm
by Downhillnz
lucasks82 wrote:I have been to a local exhaust shop and he suggested just doing a 2.5" exhaust from the existing 2" dump pipe.
Is that a good idea?
I mean wont it constrict the air flow right from the turbo and negate some of the benefits of having a big bore straight through exhaust?
Yes. I mean it would help, but if you are in the exhaust shop and getting a full exhaust made you may as well get the dump pipe made at the same time. Its a noticable difference down low.
Re: 2.5" Dump pipe for 4JB1T
Posted: Sun Apr 19, 2015 8:42 am
by SamMu93
Hi guys, click here
http://www.clubisuzu.com/viewtopic.php?f=19&t=6751 to see where I'm at with my 4jb1t build- it will answer most of your questions...
Also here's a few more pics
One of which is the factory dump pipe - note the quick warm up valve that should be reason enough to rip it out!
Re: 2.5" Dump pipe for 4JB1T
Posted: Sun Apr 19, 2015 8:45 am
by SamMu93
It's at this point that you will notice the issue now on your hands... Time to find an oil filter housing off a 4jg2 3.1...
Re: 2.5" Dump pipe for 4JB1T
Posted: Mon Apr 20, 2015 7:42 am
by turnturn
The QWS butterfly/shaft and bolts in the exhaust are about 25% of the area of the outlet. I removed them recently from my 4JB1.
Re: 2.5" Dump pipe for 4JB1T
Posted: Mon Apr 20, 2015 5:36 pm
by SamMu93
Does anyone know what this is off and if it would fit my 4jb1-t engine?
Re: 2.5" Dump pipe for 4JB1T
Posted: Tue Apr 21, 2015 3:05 am
by geeves
a link to more than the pic might help
Re: 2.5" Dump pipe for 4JB1T
Posted: Tue Apr 21, 2015 3:19 am
by SamMu93
geeves wrote:a link to more than the pic might help
http://www.freewai.com/oil-filter-with- ... -3256.htmlSays from a 4jb1 N/a but I'm unsure what model of Isuzu this would be... Any ideas?
Re: 2.5" Dump pipe for 4JB1T
Posted: Tue Apr 21, 2015 5:26 am
by geeves
that freewai.com has some reasonable prices for those having difficulty getting parts. Shippings a killer though if you have auto parts stores willing to help.
Re: 2.5" Dump pipe for 4JB1T
Posted: Tue Apr 21, 2015 5:34 am
by SamMu93
geeves wrote:that freewai.com has some reasonable prices for those having difficulty getting parts. Shippings a killer though if you have auto parts stores willing to help.
i take it you are registered to that site? Because you cant see the prices until you log in.
If you are how much was that in the link above?