PDA

View Full Version : Whats a safe boost control setting



kiteman
31-05-2013, 08:24 PM
I have an apexi ACV-R fitted and am wondering whats a safe max setting.
Today I pushed it to 1.2 bar which is about 18 PSI.
With this setting the car is absolutely flying, but obviously I'm concerned if I can do any damage running high boost.
I have a trackday coming up next monday, and would like the car going at its very best.

adaxo
31-05-2013, 10:13 PM
The best thing to monitor if you safe (or not) is to get wideband sensor with gauge so you can see if you throw enough fuel. Every car is different so for one running 1.5 bar will be safe for other 1bar and may engine go bang.

Nick Mann
31-05-2013, 10:17 PM
What Adam said. You are probably fine at 1.2 bar, but the word in there that should worry you is "probably". Cheaper than a wideband is a rolling road run to check the afr and knock - that should let you know if it is okay. Of course, after two or three rolling road checks you will have effectively paid the same as the wideband costs in the first place.

WOODY72
01-06-2013, 07:06 AM
I think the main thing is with higher boost you have no need to rev it out in the lower gears, just use the big lump of extra torque and change up at lower revs to benefit. Just remember, high revs/high stress = BANG

kiteman
01-06-2013, 12:09 PM
Aw sh1t, and there I was thinking, push it as far as it will go.
Up to now I've been running at .95 bar without any issues, and just wound it up to see what difference it made. I must admit I was surprised and impressed with the increased power surge.
With only 2 days to go to the trackday, and not having access to either a rolling road or a wideband senser, I'll just have to have a go at what Graham suggests.

Thanks for the helpful suggestions.

Davezj
01-06-2013, 01:53 PM
I have an apexi ACV-R fitted and am wondering whats a safe max setting.
Today I pushed it to 1.2 bar which is about 18 PSI.
With this setting the car is absolutely flying, but obviously I'm concerned if I can do any damage running high boost.
I have a trackday coming up next monday, and would like the car going at its very best.


it depends on what other mods you have on your car to go along with the extra boost.
if you have not had the fuel cut limit changed then i would not have thought 0.95Bar would achievable without other mods being done, and 1.2bar will not be achievable without hitting fuel cut all the time when driving hard.
you would have to be very careful how you drove the car to avoid the fuel cut areas of the stock fuel map and that would make the car no fun to drive.
so you must have had something done to car to allow you to do this.
without an AFR gauge personally i would not go above 0.9bar until you can actually monitor what is going on, you are asking for trouble if you do.
not knowing all you mods, i would not like to say any extra boost pressure is safe. well that is ow i see it.
so you would have to provide more info.

which pretty much what the above people say.

i regularly hit 1.5-1.6 bar in tip so the gear (4,5) is held in high gears and i go to WOT , over taking on the motorway, and i can do this with AFR about 11:1 and no knock. this is not intentioal but i have an odd issue with my boost control, i can't say this is a safe way to run as i have no idea how long my engine will last if continue to do this. but it a lot of fun.
i have noticed that on a 3rd gear power pull for about 40-70mph the max boost pressure my turbos will produce is about 1.4 bar tailing off to about 1.0bar at 6500rpm, so you are not far from running the turbos at there limit.
but i have extra fuel added to cope with the extra boost.

fassi1
01-06-2013, 03:26 PM
I reckon you will find 0.9-1bar giving you enough power around the track,
Good handling will improve performance the most on the track.