boosting question

That spinning thing that makes all of the cool noises. OE and Aftermarket.

Moderators: Helpinators, Moderators

Post Reply
Autotech
In Neutral
Posts: 22
Joined: Sun Oct 02, 2005 12:07 am

boosting question

Post by Autotech »

I just picked up manual boost controller, and it will be a little while before i get my intercool (have one, just no pipes to install it) how much boost can i run safely on w/o an intercooler.
stipro
Third Gear
Posts: 699
Joined: Mon Apr 26, 2004 4:20 am
Location: Calgary, Canada

Post by stipro »

If I were you, I would just run stock pressure. Its safer that way. MBC have a tendency to let the boost "spike", raising boost above what may be safe without an intercooler, it will only do this breifly though.

Thats what I think.

Its up to you. But if you decide against that, 10psi would be about max.
1994 ABM Sport Sedan-Not stock
1990 L series/turbo-Rally project
free5ty1e
Fifth Gear
Posts: 2268
Joined: Wed Nov 12, 2003 12:26 am
Location: USA: Central FL
Contact:

Post by free5ty1e »

Yeah, you probably don't want to run any more than 10psig without an intercooler.

Unfortunately with a MBC the boost spikes can be pretty bad in our cars... a second or two sometimes. You'd probably be better off with the stock electronic controller, which regulates at 8.7psig... no spikes. You may end up with some areas of lower than stock performance due to adjustments made to minimize the boost spiking.
-Chris
91SS 4EAT stock, 200k mi
91SS 5MT rebuilt engine waiting for a shell
93TW 4EAT, Forester lift, 3" TBE, 11psi, 200k mi
94SS 5MT4.11+rLSD 311k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
aspect
First Gear
Posts: 224
Joined: Mon Feb 09, 2004 6:57 am
Location: Victoria, BC, Canada

Post by aspect »

Does anybody have any information to back up the 10 psi max w/o IC?
dirt-covered 91 SS prorally
pat richard roll cage, DMS 50mm, stickers...
SOLD :(

99 impreza RS
ver. 7 sti swap, ver. 6 RA suspension, JDM bodywork, rotated GT28rs
Bane
First Gear
Posts: 176
Joined: Wed Jun 29, 2005 12:23 pm
Location: Cambridge, Ontario

Post by Bane »

I ran 8/11 psi on my car for almost a year, without an intercooler (dual stage boost controller)

I found that with my occasional spike i would hit about 12-13psi... as said before for a second or so (when set to 2nd stage boost).

that year of driving equates to roughly 60000km.

never had any issues.

the 8 psi was for bettery fuel economy
11psi for when the wife wasn't in the car and having fun.

Mind you i installed a 3" turbo-back exhaust, with only 1 high flow cat in the midpipe, prior to bumping up the boost.
I also installed a pneumatic fcd just in case of boost cut.

The setup is different now... bigger turbo and intercooler, higher boost, but it's still the same concept.
James L

'07 Magnum SXT - not stock
-
'93 Legacy Turbo SS - 5spd conv, vf34, intercooled, K&N, dual stage mbc 11/16psi, hks 3" turbo-back w/hi-flow cat, kyb's, ADR 18" rims w/225/35/18zr's, 7" touch screen w/race camera
Post Reply