8# of boost on a 16G, and other turbo Q's...

[gloryaccordy]

Would it work on a stock F22? I know ideally 10-12# works for our motors, but if I wanted to run 7-8# on a 16G would it never spool?

The way I understand it, 14B/T-25/ T3/T4 .40-.50 trim=7-9#, lil 16G/ T3/T4 .55-.60 trim= 10-14#, BFT 20G= to the moon and beyond...

Also, what kind of tune is needed for running 7-8# of boost? And would I have to retune to upgrade the turbo later on?

[d112crzy]

you tune to whatever you want it tuned at.

heres a list of the stock WG pressures of those junkyard turbos(dsm, t3's...)
you cannot go lower than the stock wg pressure unless you make a custom actuator.
http://www.homemadeturbo.com/forum/i...?topic=27392.0

and on the spooling question, no, it would spool, why wouldnt it? just 8psi isnt gona give you as much as a punch as 10psi will.

[maroonaccord2.2]

I'm not running boost yet, but I can tell you that it will spool, but your wastegate would regulate the max boost pressure (obviously up to the turbos limits, and the engine's for that matter). Spooling is a direct relation between the exhaust gas pressure, and the turbo/impeller (hot side) of the kompressor (with regards to the size/pitch/stage)..... The BOV also helps keep 'er spooled up when the throttle (butterfly) is closed between gears.....

I am not sure about the tuning....from what I've observed it's critical to understand the correct way to tune so that one doesn't grenade a motor!! I would like more info on engine management 2.....

[owequitit]

A blow off valve isn't really intended to keep the turbo spooled. It is designed to release the sudden build up in pressure when the throttle closes suddenly. It takes a moment for the turbo to begin to decellerate, and it is still producing boost when the plate slams shut. Without the Blow off valve, the pressure spike can cause a compressor stall (the air flows backwards through the compressor) causing severe compressor damage.

It can be considered a side effect I suppose, because it also helps prevent surging, which is an insipient compressor stall.

[maroonaccord2.2]

That's exactly what it's for, and you just said what I did.... Why else would it be there?!! It illevaites that excess pressure, so it doesn't back up to the compressor side, and hinder the momentum that it has with no exhaust pressure behind it. It's kinda like, is the glass half-full or half-empty. lol

[KillerCam282]

Wastegate setting has a direct corelation to spool up time. Lower the setting, the quicker wastegate opens, because you reached your target psi.

[maroonaccord2.2]

Agreed, the lower the setting.... the sooner it's going to open to bleed excess boost pressure. But at the beginning of boost, it should spool-up at the same rate, the difference obviously is the end boost output.

[flacopower]

whats the difference between running 8 psi and 10 psi? as long as you have enough fuel and proper tunning you should be alright either way

[92ex]

Your engine is running 14.7 atmospheric pressure normally. When you turbo and add 8psi to it, the engine has 22.7 pressure in it, so it's combusting more air making more power. When you have the turbo at 10psi, you have 24.7 pressure in the engine, making even more power then 8 psi.

More psi=more power

[flacopower]

Your engine is running 14.7 atmospheric pressure normally. When you turbo and add 8psi to it, the engine has 22.7 pressure in it, so it's combusting more air making more power. When you have the turbo at 10psi, you have 24.7 pressure in the engine, making even more power then 8 psi.

More psi=more power

thanks for the lesson on barometic pressure. however that wasn't the question. i was stating that 2 psi doesn't make a difference if you are properly tuned (no knock or timing being pulled) and have enough fuel being fed into your engine.

[92ex]

sorry, misunderstood your question. only difference is your putting more stress on the engine increasing the likelyhood of your ringlands going bye bye

[gloryaccordy]

Yea I'm in fear of my ringlands becoming exhaust gas...also, would 10psi on a T25 be the same as 10psi on a 16g, fuel map wise?

[92ex]

Yea I'm in fear of my ringlands becoming exhaust gas...also, would 10psi on a T25 be the same as 10psi on a 16g, fuel map wise?

NO. t25 would have completely different fuel/ignition curve. you would need to have more fuel earlier and retarded ignition earlier then a 16g. If someone doesn't have a map for it already, use a 14b map and richen it up and retard boost earlier and tune from there

[KoNEY]

Your engine is running 14.7 atmospheric pressure normally. When you turbo and add 8psi to it, the engine has 22.7 pressure in it, so it's combusting more air making more power. When you have the turbo at 10psi, you have 24.7 pressure in the engine, making even more power then 8 psi.

More psi=more power

Actually, the engine runs @ 0 psi....or it does according to my boost gauge. My charge pipes aren't running into my engine yet, and the boost gauge reads like 14.X vacuum @ idle. The more the throttle is opened the more the vacuum drops, so when you're running WOT, there is essentially no vacuum, which means that the 8 psi is what it is, 8 psi...

[high c]

Actually, the engine runs @ 0 psi....or it does according to my boost gauge. My charge pipes aren't running into my engine yet, and the boost gauge reads like 14.X vacuum @ idle. The more the throttle is opened the more the vacuum drops, so when you're running WOT, there is essentially no vacuum, which means that the 8 psi is what it is, 8 psi...

atmospheric pressure is technically 14.7. It is kinda confusing to explain but it is right. Only reason your boost gauge at wide open throttle reads 0, rahter then 14.7 (atmosphere) is because the 14.7 is literally pressure in the atmosphere, not in your engine.

sorry if that was more confusing then when it was started~ but it is correct~
justin