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got my new dumps and there is no spilter in them, anyone got any idea why tomei dont run them?

the mines and nismo and midori dumps all run one, which i think is the right way to do it,so im thinking of welding a spilter in them.

im going to be running 25psi with 2860-5s so perhaps there wont be as much gas coming out the internal gate there for a spilter not needed?

any opinions?

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Mines also make a non-split dump for the gtr.

Tomei never used a split design, i think its mainly due to the length of the gtr dumps, they are too short and therefore the split causes unnecessary turbulence. Take alook at the Greddy/Trust Dump/ Pipes they are the one of the better split design as the length is alot longer.

edit: Also the Older Tomei design is the largest dia dump pipes for the gtr, the newer design (lost-wax design) is i think 5mm smaller in dia

Edited by Kaido_RR

others here seem to have only good things to say about the tomei dumps so i guess they must work, any idea why tomei done away with the spilter? i cant find any thing on there web site

simply because you don't need a split on a bell mouth style dump, it just takes up useful space.

The only reasonably split dump on the market are Trust split dump/front pipe combo where the split is like 30cm long, not 5cm like HKS as an example.

yep, the benefit of the split wastegate pipe is a bit debatable. having a big bell mouth design means allowing the gas to expand immediately exiting the turbine housing which is great flow velocity and flow. don't modify them. if you really want split pipes just switch to HKS ones and flog the tomeis. personally though I would just stick with the tomei's. :)

Here's an interesting hybrid style dump made in the US. Note the splitter is only about an inch long if that. Basically bell mouth style with splitter to separate wastegate gasses immediately aft of the turbine. Then allows gasses to merge and expand in the main body of the dump.

Dumppipe.jpg

Edited by juggernaut1

my garrett 2860-7 turbos (and possibly others too) have this splitter cast into the exhaust housing between the wastegate flap and exhaust turbine.

is this to reduce turbulance ? if so then a spit dump pipe is not needed

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