Sideo

if i am wrong, please correct me, im not trying to be cheap, its just that i dont have one yet. it seems that boost controllers only raise the stock boost level, but cant go any lower than stock, is that right? I am wondering if i will be ok without a boost controller for a few weeks with a ported wastegate, and the manifold modified to allow it to open more. the car isnt running yet but i want to make sure i will be ok for a little while.

4CN A1R

iTrader: (6)

a boost controller on the lowest setting should generate 7-8psi on primary and secondary

parid

A boost controller won't let you run anything less than what the wastegate spring is. It's 8psi on the FD. Which is less than what the stock boost control is set to. So technically you could just run wastegate boost without any controller and it would be less than stock.

Assuming you haven't left out any other critical details, you shouldn't have any problems with the stock boost control and a ported wastegate. If anything, it should help you if you have boost creep issues.

RX7LINK

iTrader: (3)

you have a PFC. its not the best to control boost but surprisingly it works quite well

Sideo

i thought the pfc could not control boost unless you bought the boost attachment for it.

Mahjik

iTrader: (1)

I can, but it just uses the same mechanics the stock ECU uses so it's prone to the same issues.

Rotary Potato

Correct, a boost controller can only raise boost, not lower it. It keeps the wastegate flap held down longer so that you can raise your boost. It doesn't open it earlier or anything if you want lower boost. Porting your wastegate and installing a boost controller do two different things so your statement about "will I be ok for a few weeks....." doesn't make sense. If your car is more or less stock, you won't need to port the wastegate or get a boost controller. If you want to raise boost, get a boost controller. If you want to prevent boost creep, port your wastegate.

Mahjik

iTrader: (1)

That's not technically correct. A boost controller can lower boost, but it cannot lower it below what the wastegate spring allows. The stock wastegate spring allows about 7 PSI. So with an electronic boost controller, such as a Profec, installed, turning off the boost controller yields the lowest the wastegate allows which is lower than "stock" boost.

The cool thing is that something like the Profec has 2 boost settings (high & low). However, you effectively have 3:

Off - 7 PSI
Low - 10 PSI
High - 13 PSI

or whatever you set the low and high to....

Rotary Potato

Yes, you are correct..... as usual. I should have said not lower than the wastegate spring allows. I knew it in my head, but didn't get it into words, lol.

wolfman

iTrader: (2)

If you want to keep the boost under control, I'd suggest the Greddy eManage. It's a piggy back onto the stock ECU and prevents boost creep.

Sideo

my car is not stock. as it says in my signature i have full 3 inch exhaust, ported TB UIM LIM streetport, alot of flow mods. and like i said in my post i did port the wastegate. i just wanted to make sure it would not overboost without a boost controller, but it looks like i dont need one unless i want to raise the boost.

Smitter

i ran 14lbs on the stock twins with no boost controller, just the power fc and had no troubles.

dhays

iTrader: (1)

You really never mentioned why you are concerned about your boost levels and why only for a few weeks? It sounds to me as if what you want to avoid are boost spikes, correct? From my limited understanding, you could easily get boost spikes with your current mods. Are you waiting until you get a tune?

If it is boost spikes you are worried about, then just don't drive the car hard for a few weeks until whatever you are waiting for is taken care of. Or am I missing something here?

4CN A1R

iTrader: (6)

i have the old school profec b and my boost stays at whatever i last set it at. with it on or off. the only difference i notice, is the gain. it pulls harder with the controller on

Smitter

i should have added that i did this with full exhaust, intake & large street ported motor