External Wastegate On Exhaust Housing?

[GTR-026tt]

I am low mounting a BLITZ K5-660R on my RB25 stroker i was wondering if i can put the Tial 38mm gate on the exhaust housing ( weld it on properly ofcourse) what will the con's and pro's be?

Where is the best physical spot for response/power * boost controll.

Edited February 9, 2007 by GTR-026tt

[BHDave]

It's not an ideal solution but there are enough cars out there running this type of setup that you can be fairly sure it'll work to some extent.

I think you'd really want to get the outlet as close as possible to the exhaust housing inlet flange where the cross section is largest and it is less likely to completely stuff up the gas flow into the turbine.

[GTR1993]

Not ideal? Have a look at the old toyota factory GTP cars they run them all off the housing, best way to do it.

This is where you should put it so it doesnt obstruct flow, if you really want i can take a photo from corkey bell that shows it done exactly this way on the toyota race cars.

[Adriano]

It depends on the size of the port in the flange, with the wasegate in the turbo housing, all the exhaust gas must pass through the flange, and can cause high ex manifold backpressure, although at these sort of power levels i cant imagine it being a major problem.

[GTR-026tt]

OK

The turbo flange is T2 1/4 and the exhaust housing is quite large for its size. The main reason i want to do this is because its cheap, easy and hopefully works well? Will it effect boost response ?

Thanks

[BHDave]

Not ideal? Have a look at the old toyota factory GTP cars they run them all off the housing, best way to do it.

This is where you should put it so it doesnt obstruct flow, if you really want i can take a photo from corkey bell that shows it done exactly this way on the toyota race cars.

If you want to argue i can refer to the same book and point out that the TAG f1 engine integrates the wastegate before the turbine inlet, as does every recent LMGT engine i have seen photos of. LMGT engines are arguable at the fore front of turbo engine development now, not 20 years ago.

As i said in the first place, not ideal but it works.