boostedxs

all I'm wanting to do right now is run this little 9lbs and be able to keep that 9lbs all the way to 6500. I was hoping I could accomplish this with just spring pressure but from what you guys are telling me I need a controller on this thing, likely due to back presdure. so now I wondering how all the factory setups keep their boost until redline without a controller

smokeshow

iTrader: (17)

Modern factory boost control is more advanced than the best boost controllers you can buy. What air filter and pre-turbo intake piping is on this thing?

RealQuick

iTrader: (14)

Exactly what I was going to ask. Boost shouldn't be dropping off when running off the gate.

jasonsnova

My car is running on the spring (12lbs) and it goes to and stays right at 12lbs, but I am running 2 precision 46mm gates. Also it is referenced off the turbo
Maybe not enough gate??

Dian

"so now I wondering how all the factory setups keep their boost until redline without a controller"

they dont. that used to be a very typical situation on turboed cars. boost would typically drop from 0.8 bar to 0.5 bar at redline. thats why they were so easy to tune. if you took them to 1.0 bar and kept it there you had a 0.5 bar difference.

kingtal0n

iTrader: (1)

many old turbo cars use a solenoid that is computer activated to increase wastegate duty% after some rpm. Not necessarily because the exhaust gas pressure was high, but it certainly helps to make sure boost goes up and not down no matter what.

The exhaust 'valve' of the wastagate has a face diameter that directly influences the applied force from exhaust gas. Larger faces of larger valves allow more of the exhaust gas to apply a force to the valve and open it. A gate can open based on exhaust gas pressure alone. Think about this- if you left the spring out of the gate and didn't connect it to anything, would it still open? Of course common sense tells you that the exhaust is going to open the gate, because there is no force coming down from above. The same thing happens when there is a spring holding it shut- but now you see that the spring force might be overcome by exhaust gas pressure. There are all kinds of calculations online about how much force a given size face wastegate valve would take vs spring pressure rates and so forth, if you are interested it should not be difficult to find.

boostedxs

boostedxs

boostedxs

Im just using a 1 piece conical filter attached directly onto the turbo. and as you can see last winter I got bored one day and half *** assembled my kit when my old lady wasn't home haha but it gives you a good idea of how my setup is

boostedxs

talon I understand how a wastegate works, I just assumed it would hold pressure more evenly through the rpms than what mine seems to be doing. if I didn't know any better I'd say my gate is cracking at the right psi but it's being blown open further than it really should, causing boost to leak off more than anticipated. If you read my post I suspected this front the very beginning but you guys helped she'd some further light onto it. Im going to just go ahead and hook up my eboost2 and see what she does. thank you guys for the help, that's why I enjoy this site a ton of good info here depending on who you talk to

stevieturbo

Ummmm, their ecu controls it, and they will have spend tens of thousands of hours testing to ensure the engine, turbo, tuning etc etc etc is all matched to what they want the car to do.

And as others say, more often than not OEM will allow higher boost in mid range, tapering off at higher rpm. But as with everything...there are many many variables.

boostedxs

I'm good with the variables, that's to be expected with any build forced induction or not. this isn't my first build, but it is my first build trying to run off just spring pressure so this threw me off a bit. my last build i hooked up a manual controller before i ever started the car.I guess my only other question is should I reference my boost controller from the manifold or is it best to just reference it from the nipple on the turbo or does it matter and why? instructions on the wastage say use turbo for reference but peoplease are telling me different. I understand the loss of boost through the system but with a controller it seems it would make up for that loss no matter how I reference it. if I'm wrong please tell me, I don't claim to know everything in the world I just wanna know the proper way to go that way if I teach someone else down the road I actuslly know wtf I'm taking about lol

stevieturbo

I would never use intake manifold.

But as you're experiencing a drop at higher loads, you could reference close to the throttle but on the boost pipe side.

But ultimately if you have a lot of EGBP or some other build limitation, then it will need a different fix which could be a different plumbing configuration for the gate, or a programmable controller.

RealQuick

iTrader: (14)

I suspect that if you are using wastegate, andboost frops off, then it will do the same with the controller. Most controllers use a solenoid with a commanded duty cycle. Since the commandedduty cycle is fixed, whatever is causing your drop off with just wastegate will be seen with the increased boost as well. Now, if the controller had the ability to increase duty cycle during the pull (scramble mode), then you could mask the boost falling off by increasing duty cycle.

RealQuick

iTrader: (14)

Oh, and next time on the dyno run the car with filter on and off since it's easy to get to. You may find boost does not fall off as much.

stevieturbo

The Eboost does have that ability and scramble mode is something different

RealQuick

iTrader: (14)

yeah scramble mode lets you run 2 different duty cycles based off of time, I didn't realize that the eboost had a different feature the varied duty cycle to maintain a specific boost level.

sbcgenII

iTrader: (1)

Fire ring installed in the wastegates? Is the BOV staying closed? How is your bov plumed?

boostedxs

I have verified that fire ring is installed and looks to be seating properly. what I need to do it build a rig to test my wastegate that would probably solve this issue pretty quickly. bov is on exit side of intercooler, this is how all the huron speed t4 kits are set up and I've never heard of this issue. I will check on all my lines though and make sure nothings leaking. I'll keep you guys updated on the fix. I don't have my car at home it's at my shop but I'll jump back on it this week at down point. thak you guys for the input

sbcgenII

iTrader: (1)

Not to concered where the bov is at but where it is getting its vac/boost signal and if it open at idle.