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Maximum boost on std setup

1K views 17 replies 7 participants last post by  Matheus428 
#1 ·
My calibra was underboosting before the waterpump blew up it was only boosting up to .6 and then holding .4, the actuator was set right at the end of the thread so i wound it up about 2 inches and now it overboosts to 1 bar and holds .8 i get no warning lights and it runs fine and feels superb to drive......Is this safe to do on a standard setup or am risking blowing more parts of the engine up.............

Cheers
 
#3 ·
No leaks, Turbo holds boost fine............I thought with the standard ecu you could only run .8 before the ecu cut the boost and the warning light came on............
Mine is a standard ecu that will hapilly run 1 bar of boost...........
 
#4 ·
oops, I just started a kinda of similar thread,
The ECU will limit the boost, You should not really be getting 1 bar unless you have something like a bleed valve that is tricking the ECU into thinking its still getting low levels.
The Standard boost you should be getting is around 7psi, mine has been increased to 12psi and has run fine for a long time, though as prev mentioned, you will need some cooling system for your engine as it will be running much hotter.
A large intercooler, a charge cooler or water injection are all good ways to reduce the temp.
 
#5 ·
Bren car is completely standard no bleed valve, I will be adding a FMIC once the water problem is sorted...........

It will happily boost to 1 bar and then hold .8 i have not tried taking it further than this, The ecu has never been replaced seems weird it will let me do this, on my old calibra i wound the nuts about 1/2 and that brought the ecu light on..................
 
#7 ·
Cheers odders maybee i wont take it any further it seems to make a huge diference running at 1 bar feels so much quicker.....................
 
#8 ·
The problem of intercooler in this case is not only the temp of air, is this cause a "drop pressure" when operate in high flow. Because this need a bigger intercooler.
I think, your internal parts can resist more than 1 bar, the problem is the detonation or fault of fuel, its the really danger for turbo engine, ALWAYS work rich mixture in turbo engine, like 700 to 800 milivolts for gasoline and 950 milivolts to 1 volt for alcohol(etanol or metanol), is the best perfomance mixture.
The other problem is your CR, but a thicker head gasket will help you. And the next step for you make a strong C20Let, is put a better exhaust manifold, and bigger turbine, for you get in up the max power rpm, and lowering the MEP(medium efetive pressure). Because in 5.400rpm max power, is danger for high power and standard internal parts. Vernier pulleys will help too for get up the max power.
I running with my car with 1.6 bar of boost, 10,8:1 of CR(alcohol), without intercooler, and the power is amazing..really nice.. Now with my new head, i will run with around 9,7:1 of CR, and 1 bar in day, day, and 1.5 bar in boost street race case..hehehe. When increase the boost the feeling is so nice, because you feel something kick your back, is not a foot of someone, is the torque!!! hehehe


cheers and good lucky,
 
#11 ·
so what boost can i turn my standard LET up to without risking melting anything?
Not too high if the rest is standard.
When you raise the boost pressure you are forcing the air through quicker and therefore it is not getting cooled as much, Warm air is very bad for your engine, you need to combat this by fitting a FMIC, or a chargecooler or water injection.
Otherwise upping the boost could end in tears.
 
#13 ·
That will be fine, wait until then before you up the boost.
Have you got a Boost Gauge?, if you are going to alter the boost levels you really do need a gauge in the car so you can moniter the levels you are setting it to.
Turning the bleed valve just a small amount can make a bigger difference than you would imagine, it's safer to start slow and work up, Start with the bleed valve shut then turn it in small amounts, mabey just a quarter turn each time until you get it to roughly where you need it then do even smaller turns to fine tune it.
 
#14 ·
Warm air is very bad for your engine,
not really.. the hot air only make bad for engine, if its cases detonation. My car have more than 150 celcius degrees in inlet air to engine, and don´t "melting".
I think, if you can lowering more CR of Let, the engine resists much more than 1 bar of boost, because my C20NE without forged pistons, standard rods(i think is not strong like Let rods), resists 1.6 bar of max boost. Running with 10,8:1 of CR and alcohol.


Cheers,
 
#15 ·
Warm air is very bad for your engine,
detonation
Warm air causes Hot spots and Detonation, are you agreeing or disagreeing?.
Warm air is bad, it needs to be cooled to a reasonable temperature, upping the boost and not lowering the temps will cause detonation, melting, hotspots etc etc.
 
#16 ·
Warm air causes Hot spots and Detonation, are you agreeing or disagreeing?.
depends of the engine and fuel.
My engine receive really hot air and dont detonation.

If you have a fuel that resists detonation, like alcohol, you can running with temps. Or if you running with so low CR, you can too running with hot temp.
But is logical if you running with low temps air, you will have more security and more power, but for it, you need chargecooler, big intercooler, bla, bla, bla.. And when don´t have money for it, you can use other exits, like me.
I try use intercooler, and my intercooler have a crap efficience in more than 1 bar. Then, i running with high boost, and without intercooler, and the power increases is marvelous.
And you have other exit for get low temp air too, is using a bigger cold part(compressor) of turbo. Bigger compressor, get less hot the air for compress, but have more lag for it.



Cheers.
 
#17 ·
Matheus, I understand what you are saying but SRi Crew mentioned his engine and ancilleries were standard as is his fuel.
So with every respect, I think he needs to be very careful with the boost levels until he finds a way to combat the higher temps.
 
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