My current wastegate (Turbonetics Deltagate) has a 7psi spring in it right now. When driving, I notice my boost slowly opens to 7psi.

4,000 RPMS = 3psi
5,500 RPMS = 5psi
6,500 RPMS = 7psi

And you can tell from the dyno chart (don't have a scanner, or else I'd post it).

I was wondering if there's any specific wastegate you can buy, where once you hit boost, the spring just stays wide open at the spring pressure?

IE: With a 7lb spring, once I hit 4,000 RPMs, stay wide open at 7psi instead of gradually climbing, or is the gradual climb standard with all wastegates?

Would it have anything to do with my turbo being too big for my car? Garrett T3/T4 (.63 turbine side and a .60 compressor side). 1.8L, 9.1 compression.

 

Dooodooodooo

 

normal.

It takes rpm's to build boost with a big ol' turbo

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iGfrequency &raquo;</TD></TR><TR><TD CLASS="quote">normal.

It takes rpm's to build boost with a big ol' turbo </TD></TR></TABLE>

Sorry, no. It doesn't take 6500 RPM's to hit full boost with a modestly sized turbo. If you think that's normal, there's something fucked with your car too.

One of the things is A) Deltagates suck and B) You have no boost controller. I had the same type of problem with my deltacreep with a .48 A/R T3/60-1, swapped it to a tial 38mm with an AVC-R and no problems. With the deltagate and no EBC the gate would slowly start to open up once it sees any boost, which takes away more exhaust flow and energy, and continues to slightly open as it sees more boost. I'd give the boost controller a shot first.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 19sec beast &raquo;</TD></TR><TR><TD CLASS="quote">I was wondering if there's any specific wastegate you can buy, where once you hit boost, the spring just stays wide open at the spring pressure?</TD></TR></TABLE>

Where is your wastegate hooked up to now? and d you have a boost controller or not?

You'll wanna have your wastegate hooked up to the intake manifold to get the results you are looking for. For the best results you can install an electric boost controller. Most EBC's will limit the amount of boost that goes from the boost source to the wastegate actuator, which means the wastegate is closed and this allows the exhaust gasses to go through the turbine which builds up your boost faster. I believe the Apexi AVCR does this. IIRC you can control how much the wastegate opens before you actually get to your desired boost level. You can make the boost rise gradual or you can make peak a lot sooner. I'd have to look at my AVCR manual, but I'm almost certain it's the WG duty cycle function.

But if your wastegate is still shut and your compressor cannot push the amount of boost you want at the RPM level you want, then there is nothing you can do to fix that. The only way to fix that problem would be to get a smaller turbine.

 

Thanks for the info!

 

this is completely off topic but your user name (19sec beast) made me LOL!

 

I had the exact same sized turbo on my 1.8LS w/ 8.5:1 compression and it still spooled up to 10psi at like 5000. (if I remember correctly)

 

Thanks notoriousB, heh. I'm not quite in the 19s, but I used to get made fun of a lot by friends when I first bought my car for buying an LS instead of a GSR. The name sort of stuck.

thanks for the reply, TurboCoop. I've already ordered my Tial 38mm, so we'll see how that works. I may go ahead and just buy the AVCR too while I'm at it.

 

Yeah, your motor really should be spooling that snail up quicker. A .48 compressor would have responded well to the limited RPM of an LS. The Tial should make a difference for you. They are really accurate. on my digital boost guage it always sits right on .50 and the spikes are only to .53 and are instantly corrected. Hope the tial helps!