pipe size

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azn2nr
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pipe size

Post by azn2nr »

i just got a quote today for pipes for a front mount. the guy i was talking to has done a good share of custom pipes on cars around salt lake and offered to do it for me for $600. theres only one problem . he told me that 2.5 is a good size but because of space avaiable in my engiin bay and in the intrest of spool time recomended 2.25 instead. he claims that avarage spool time for a civic with t3/t4 is like 4500 rpm with 2.5 in pipes but with 2.25 pipes his spool time in his civic is 3200. is there any validity in theroy to this claim. also he says hose clamps will have a hard time keeping the pipes together and that there is another type of clamp that i suould get. for you sabb 900 guys are regular hose clamps up to the task at pressures higer than 13psi?
-jason
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BAC5.2
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Post by BAC5.2 »

Intake dynamics are similar to exhaust dynamics. You want the highest velocity with the least backpressure.

A pipe that flows to well, will reduce velocity. A pipe that flows not well enough, will increase backpressure.

The outlet on a 16G, is 1 7/8". The TB is 2.75". At 14.7psi, a 16G flows around 505cfm. I'd say that you'd be well with a 2.25" pipe. I don't see a reason why you wouldn't be.

Setup has a lot to do with hose clamp holding. Matt's don't stay on for shit. I didn't blow a hose all day.
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legacy92ej22t
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Post by legacy92ej22t »

Ya, mine doesn't stay on at high boost very well. If you put a little ridge on the end of every piece though it should stay together really good with normal hose clamps.
-Matt

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kidatari
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Post by kidatari »

as legacy92ej22t said, having a bead on the pipe ends will help keep the hose couplers from blowing off at boost, but it's also important to make sure all of the pipes are 'clocked' correctly, so that when they're all connected, there won't be excess stress on the connections. Basically, you want to make sure that when you put on the silicone connectors that the pipes are parallel to each other with no angle at the outlets, because this will cause the hose couplers to pop off more easilly at boost.

Also, i'd reccomend using T-Bolt clamps on all of the couplers, because worm-drive clamps won't hold the piping together at boost. Good luck.

See the below link for good examples of the options for T-Bolt clamps-
http://www.turbohoses.com/Clamp.htm
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BAC5.2
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Post by BAC5.2 »

Oh, and a BIG thing is to use REAL connectors. Not sewer connectors, as they are not rated for pressure, temperature, or oil.

Vikash found this out the hard way at the shootout. I've been lucky so far...
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azn2nr
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Post by azn2nr »

yeah theyll be real conectors. im gonna talk to him about putting beads on the ends to, thats a real good idea
-jason
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rsstiboy
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Post by rsstiboy »

use 2" out of the turbo for about 1 1/2 feet then go to 2.5" to and through the fmic then about 1 1/2 feet before the throttle body go to 3" pipe, the reason behind this is so that there is less pressure before the throttle body so that it helps flow to your inlet manifold. it also reduces the amount of turbo flutter you'll experience by keeping the high pressure flowing to low pressure.
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