zapp109

iTrader: (13)

So after a nice long day on the dyno we aere having a hell of a time trying to control the boost on my car. 408 lq4 with bullseye s480R. I currently have a Precision 46mm right in the middle of my merge pipe on a angle..

like so



We put a medium red spring in it trying to get it to stay low psi and it still would go high. With the AEM boost controller on the lowest setting spools up @ 3800 to 11psi. Holds 11psi until about 4900 then climbs to 15.79 psi @6000 rpm. oh and at 902whp Let off at 6k... Just scary not knowing where boost is gonna be.

So now im trying to figure out if i should try to squeeze a 66mm in the spot or put another 46 on? and if i put another 46 on its going to be before the merge pipe a little so im sure that wont be good since you probably should have 1 on each pipe before the merge..

Let me know what yas think

denmah

iTrader: (2)

replace it with a giant 50mm EMUSA china gate 75 dollar test would be cheap and i would love to know the results

samdogmx

iTrader: (14)

If you haven't already, try the lightest spring they make for your gate.

IMO its easier to get better placement with two.

zapp109

iTrader: (13)

I had a 6.5psi spring in it when we started then put a red spring in it which is 3psi i believe with basically the same results.

denmah

iTrader: (2)

http://www.ebay.com/itm/Turbo-Wastegate-50mm-Type-GT-14-PSI-1-bar-BLUE-Honda-Civic-Accord-CRX-S2000-/201047521969?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ecf5dbab1&vxp=mtr

LS1NOVA

iTrader: (12)

I would put two 38mm gates on it.

zapp109

iTrader: (13)

Any downside to two 46mm on it? Bigger is better as far as wastegates are concerned right?

5mall5nail5

It'd be best if you had it in that position on the OPPOSITE side of the collector. You've got the dump on the inside radius of the turno so you're asking the exhaust, with all its velocity, to change directions dramatically. If you poke that hole on the opposite side of the collector you'd likely have much better results - you probably don't have enough pressure in the collector to really vent at that position - I have a similar issue. Further, you probably don't have an exhaust that is restrictive enough to encourage flow out the WG... so it's easier for the exhaust to go through the turbine housing vs pop out the wg hole.

5mall5nail5

Yep if you can fit dual 46's do it.

zapp109

iTrader: (13)

Thanks I think I'm gonna try to run another 46 and move them to each pipe before the merge when I get home from work I'll get a picture of my pipe and circle where I'm thinking to get some opinions.

stevieturbo

Surely a single 60mm or so would be easier than ******* about with 2 gates ?

5mall5nail5

I don't think so - at least not on the builds I've dealt with - the 60mm tials are GIGANTIC. They weigh a ton. I worry about them cracking the welds and falling off lol.

stevieturbo

Some people hang turbos off the welds ! Although to be fair eventually they do crack lol.

Lets face it though, most stainless cracks eventually when turbochargers are involved anyway

samdogmx

iTrader: (14)

no such thing as too big. I am doing to 60s on mine.

zapp109

iTrader: (13)

This is what im thinking... any issue here? obviously the passenger side run to the wastegate would be longer dont know if that would matter.