Seeking advice on fine tuning wastegate on my compound setup

[prostreeter600]

Recently installed a new compound setup . Need help on best way to dial in my wastegate around my high pressure turbo . It is a Turbonetics New Generation HP 50 mm. Can I dial it in with just spring and preload or do I need to connect a sensing line from boost pipe to the lower port with a boost controller/press regulator in that sensing line ? Approximately what boost pressure do I want the gate to start diverting some of the exhaust to my big charger. I am installing a boost gauge at the big charger as well as a drive pressure gauge . I already have a boost gauge at my cold pipe .What pressure should I shoot for between the big charger and high pressure chargerand ?What drive pressure is ideal or within limits to help my motor stay together ?All my mods are my Sig. Trying to maximize my setup And HELL WE WANNA GO FASTER !!! Thanks in Advance

 

[prostreeter600]

Anybody have any expierence with wastegates ?

 

[S Phinney]

I run a Turbo Smart 60mm gate. I tried most every way that guys recommended on here. None of those ways worked properly. It was hard comprehending how the manufacture said do it but it worked perfectly. I would highly recommend using the methods that Turbinetics says use. If needed call their support number and talk with a rep. Explain what your are trying to accomplish and try what they recommend. I use a manual controller made for this. Most guys try using a air tank regulator. They are not the same when it come it dialing it in. I use the highest spring pressure combination that my gate has available. Pressure from hot side pipe is applied to the bottom port of the gate through the controller and the top port is vented to atmosphere. Some how it actually is able to apply more pressure than the 33 lbs from the springs. Normal thinking would say that pressure to the bottom would be counterproductive but it isn't in my application. Believe me I tried every possible combination out there. I now have full range control of how much and how the boost is produced. You want to have as much total boost with the least drive pressure numbers. That ratio would be ideal at or near 1 to 1. Most setups cannot achieve those ratios because the turbos and piping are not matched well within the system. Gate setup really needs to be very close before you can finally get the most out of the tuning. Hope this helps you some.

 

[prostreeter600]

S Phinney were you running a compound setup and wastegating around your high pressure turbo or just a single trying to control the amount of boost on a single ? Your spot on as for what Turbonetics told me to do. Run a sensing line from bottom port to discharge side of my high pressure. At what point(Boost) do you want the wastegate to open to drive the big charger harder ? I'm guessing the boost pressure from the sensing line to the bottom of the diaphragm of the wastegate helps open it up when you regulate that pressure that determines at what point it opens. I guess the exhaust pressure itself is not sufficient to open the wastegate. How can you tell when the wastegate opens ? Thanks for your help

 

[DPC]

I used a regulator from the high psi turbo to the top of the gate and a line from the low psi turbo to the bottom of the gate. I started with just spring psi (regulator closed) and started test driving watching boost and drive psi. What ended up working best for me was 28# of spring psi with 20# of regulator psi. Total boost was 75# and drive was around 85-90#. This took tons of test driving along with logging to get it dialed in.

 

[prostreeter600]

Good info . Sounds like I need to put the heaviest spring in it and get a regulator as well . Looks like you got yours dialed in pretty good . Thanks for your help .

 

[S Phinney]

My setup is triples. I gated the high pressure. Total boost is around 85 drive pressure is around 100.

 

[prostreeter600]

So yours is setup to regulate overall amount of boost ? With a twist of the knob you can add or subtract boost ? I believe that's what your saying . Mine is setup to divert exhaust around the high pressure once its spooled over to the atmospheric to help drive it harder. I take it 1/1 on drive pressure is hard to achieve ? I take it your triples are capable of more than 85 psi but it would also bring on more drive pressure which wouldn't be good on the motor ? I appreciate the info

 

[S Phinney]

It set up to divert air around the high pressure charger. When it is setup properly you can add the amount produced by the high pressure one or the atmosphere charger/chargers. I could make more boost with more fuel. It does that on less than 2000us. The more you gate around the high pressure the lower the drive pressure becomes and the more boost is produced via atmosphere charger. If it isn't setup properly you can't make a dent in the balance between high and low pressures or drive pressures. There are a lot of variables that have to be taken into account for a great operating compound setup. For the most part I am at or below 1 to 1 ratios. I am not at wot. Most guys are not at 1 to 1 either. I would say anything that is within the 1 to 1.2 ratio range are very well managed and will be efficient at making power.

 

[prostreeter600]

Thanks for your help . How long before you make a 1/4 mile run on your triple setup ?

 

[Ne-max]

Bumping this up. Just got my new set up going. Time to dial in gate. Right now it's not plumbed. I am just using the spring. In tune 2 I am making 87 psi total boost and 38 psi between the 72s & 80. But top end it sounds like the gates opening on me. Sound about right for pressures?