20psi on pump gas, if you dont know, dont answer...
- Thread starter Reign_Maker
- Start date
bigaaron said:
i agree. but if you are making xxx rwhp on xx psi, then more psi = more hp!
i am a fiend for power, but as most know im always on the cautious side of things. id rather run a little less boost and a little richer to sacrifice a little power for something that is going to last.
another thought- timing.
it was mentioned about a more conservative timing curve. you can do that to run more boost. but i think you will find power and response will be better on a more aggressive timing curve and lower boost than the other way around.
all said and done, unless you welded the top shut on the wg, you may consider going to a lighter spring. if any consolation, sean (x-man) ran 32psi on a 10.5psi spring with the same turbo.
MAFT-Pro still scales the airflow signal - Unless you are actively changing the timing, I say no, still.
MBT is the best place to start with timing, imho. I go about 3 degrees under that, myself.
MBT is the best place to start with timing, imho. I go about 3 degrees under that, myself.
dbsupra90 said:
Yes and no :icon_bigg Up to a point.
When I was running a 50trim c26 it made 370whp and 395tq at about 20psi on 91 octane. When the boost was increased to 25psi it made 370whp. :biglaugh: In that case there was increased pressure, but no increase in flow. Also, if you are running a stock ecu the hp from the increase in pressure may be cancelled out by the ecu decreasing the timing. If the ecu kept the timing the same at 20psi as it was as 5psi, it would knock.
Doward, I dont have any clue what you posted... I've never learned to read maps, so forgive me... But to answer your question: my IC is 12X24X4 with 3" IC pipes and the Q45 tb, and my turbine A/R is 81... Thanks for the info, its helping...
I appreciate all the info guys... My goal is to have no less than 550hp for the street tune... I dont care if any of you think its stupid, or a waste, or I'll have traction issues... 90% of the people here have never touched 500hp, I have, and I LOVED it... To me, 550hp on pump would be just a blast on the street...
From what I gather, my options are as follows... Meth injection, mix high oct with 93, conservative tune, or drop the spring rate...
I kick myself in the ass, I should've posted this a long time ago... Its going to be a PITA to pull that w/g out... It was a bitch just gettin that spring in... There's no way to go lower than spring rate is there?
I appreciate all the info guys... My goal is to have no less than 550hp for the street tune... I dont care if any of you think its stupid, or a waste, or I'll have traction issues... 90% of the people here have never touched 500hp, I have, and I LOVED it... To me, 550hp on pump would be just a blast on the street...
From what I gather, my options are as follows... Meth injection, mix high oct with 93, conservative tune, or drop the spring rate...
I kick myself in the ass, I should've posted this a long time ago... Its going to be a PITA to pull that w/g out... It was a bitch just gettin that spring in... There's no way to go lower than spring rate is there?
Not properly, no. Replace the spring - with all the work you've done already, it's not that much more.
As for what I posted - See the island in the middle? That's where the turbo is at it's most efficient - in this case, 76% efficient. The next island is 74%, and the island you are on when you are asking the turbo for the most airflow you will use, is at 72%.
That's very good - plot that point (2.36 PR on the Y axis, 55lbs/min on the X axis) on another map (say a T04e 57trim) and you'll see you are more like 60% efficient. That's 12% less power, right there.
You will have *zero* problems attaining your goal of 550hp on pump with that turbo. I will recommend a set of cams, though. Believe me when I say you CAN make that 550hp under 20psi of boost.
As for what I posted - See the island in the middle? That's where the turbo is at it's most efficient - in this case, 76% efficient. The next island is 74%, and the island you are on when you are asking the turbo for the most airflow you will use, is at 72%.
That's very good - plot that point (2.36 PR on the Y axis, 55lbs/min on the X axis) on another map (say a T04e 57trim) and you'll see you are more like 60% efficient. That's 12% less power, right there.
You will have *zero* problems attaining your goal of 550hp on pump with that turbo. I will recommend a set of cams, though. Believe me when I say you CAN make that 550hp under 20psi of boost.
how about putting a water injection kit on it? then 20 psi should be no problem on pump gas. summit sells a kit for 299, run a 50-50 mix of water and methanol, or just pour windshield washer fluid into it. should make 20psi no problem on pump gas.
i didnt think 20 psi on pump would be that much of a problem on a turbo that size anyway.
i didnt think 20 psi on pump would be that much of a problem on a turbo that size anyway.
My AVC-R saids that I'm running 1.33 bar which should be 20psi, but my boost gauge always reads about 16psi. I don't know which one is right, but from reading all of these posts, it doesn't sound like 20psi is safe. I run nothing but 93 octane, and it sounds like I'm driving a grenade waiting to explode.................:nono:
suprahero said:
No way, you have a 1jz, so the standard laws of physics don't apply. :biglaugh: 20 psi on 93 octane is better then 20 psi on 91 octane. I don't think you have any issues with pinging so you should be ok.
If you have the AEM, you should be able to back off the timing to run 20psi. I would find a good tuner that knows how to monitor knock and can establish a conservative timing table that would allow you to run 20psi on 93. But then again, the question is how much power will you lose with lower timing. Find a good tuner.
With that said. If I were you, I would invest in a methonal injection. That seems to be the most full proof way of running more boost on pump gas.
With that said. If I were you, I would invest in a methonal injection. That seems to be the most full proof way of running more boost on pump gas.
tissimo said:
V1/T1 = V2/T2
You heat the air an extra 12%, that's 12% less (the volume increases by 12%, same mass, density drops) air going into your motor.
a good intercooler will decrease the heat quite a bit.. reducing the temp difference..Doward said:
And can someone please explain to me where this notion of needing more timing to make more power ever came into play??
Think about the way your internal combustion engine works. You have a precise moment when you need to fire your spark plug in order to maximize the amount of force acting on the crankshaft (via the connecting rod)
In an N/A application, you CAN increase the peak cylinder pressure by advancing timing - but what I don't think some of you are seeing, is that the point of MAXIMUM peak cylinder pressure is going to occur when the piston is AT TDC! Think about that for JUST A MINUTE PEOPLE!!
IF your piston is @ TDC, THE MAJORITY of the force is going to be transmitted directly down the rod, and directly into the crankshaft. Remember, the crank is going to be pointing straight up - not a very smooth rotation of the crank, is it?
Now do that when the crankshaft is oh... 15-20 degrees out. That downward push is now going to cause the crankshaft to spin, using more of the available (which WILL be less than the TDC example) force to do so.
Even further to consider, is that the denser air/fuel mass we run in a turbocharged engine, will burn SLOWER than one of atmospheric pressure (N/A) - This causes the flame front to take a little longer to reach combustion, and the cylinder pressures will peak around 2-5 degrees further out from where they would in an N/A setup. FURTHER, since there is more air/fuel mass to ignite and burn, the cylinder pressures will remain HIGHER for a LONGER period of crankshaft turn - this is why turbocharging creates so much torque.
That said, hp is directly related to torque. HP = tq*rpm/5252 as a matter of fact.
So what am I getting at here? You run into detonation issues when your cylinder pressures peak out in such a way that the flame front becomes uncontrolled. This causes a hell of a lot of heat, and makes way for pre-ignition - this will kill your engine faster than anything, because you're trying to ignite the air/fuel mixture before the crank is ever brought around to spin back downward.
If you want to prevent your cylinder pressure from peaking out too early in the crankshaft cycle, you need to ensure your timing is not TOO FAR advanced. That said, you want to run MINIMUM timing to create BEST TORQUE.
Why? Because that is the point where you've ignited the spark plug in order to peak your cylinder pressures 15-20 degrees AFTER top dead center, in order to create the MOST PRESSURE ON THE crankshaft during the 90 degrees of rotation that you can do so. If you take your timing to MBT, and then subtract a couple degrees (as a 'safety zone' then you will never run into detonation due to timing issues.
You will get into detonation due to fueling issues (insufficient octane, not enough fuel) but not due to ignition timing.
Think about the way your internal combustion engine works. You have a precise moment when you need to fire your spark plug in order to maximize the amount of force acting on the crankshaft (via the connecting rod)
In an N/A application, you CAN increase the peak cylinder pressure by advancing timing - but what I don't think some of you are seeing, is that the point of MAXIMUM peak cylinder pressure is going to occur when the piston is AT TDC! Think about that for JUST A MINUTE PEOPLE!!
IF your piston is @ TDC, THE MAJORITY of the force is going to be transmitted directly down the rod, and directly into the crankshaft. Remember, the crank is going to be pointing straight up - not a very smooth rotation of the crank, is it?
Now do that when the crankshaft is oh... 15-20 degrees out. That downward push is now going to cause the crankshaft to spin, using more of the available (which WILL be less than the TDC example) force to do so.
Even further to consider, is that the denser air/fuel mass we run in a turbocharged engine, will burn SLOWER than one of atmospheric pressure (N/A) - This causes the flame front to take a little longer to reach combustion, and the cylinder pressures will peak around 2-5 degrees further out from where they would in an N/A setup. FURTHER, since there is more air/fuel mass to ignite and burn, the cylinder pressures will remain HIGHER for a LONGER period of crankshaft turn - this is why turbocharging creates so much torque.
That said, hp is directly related to torque. HP = tq*rpm/5252 as a matter of fact.
So what am I getting at here? You run into detonation issues when your cylinder pressures peak out in such a way that the flame front becomes uncontrolled. This causes a hell of a lot of heat, and makes way for pre-ignition - this will kill your engine faster than anything, because you're trying to ignite the air/fuel mixture before the crank is ever brought around to spin back downward.
If you want to prevent your cylinder pressure from peaking out too early in the crankshaft cycle, you need to ensure your timing is not TOO FAR advanced. That said, you want to run MINIMUM timing to create BEST TORQUE.
Why? Because that is the point where you've ignited the spark plug in order to peak your cylinder pressures 15-20 degrees AFTER top dead center, in order to create the MOST PRESSURE ON THE crankshaft during the 90 degrees of rotation that you can do so. If you take your timing to MBT, and then subtract a couple degrees (as a 'safety zone' then you will never run into detonation due to timing issues.
You will get into detonation due to fueling issues (insufficient octane, not enough fuel) but not due to ignition timing.
tissimo said:
Not so - say you have an intercooler that decreases intake temp vs ambient temp by 85%. (this is how intercoolers are rated, btw - by their efficiency, that is to say the delta T of air through it)
If you have 340K air coming in, you have 289K air out.
If you have 381K air coming in, you have 324K air out.
Either way, you have the same constant % increase in temperature, the same % increase in volume, and the same % decrease in moles of air into your engine.
hummmmmm i ran 20 psi on my 86 car wiht 57 trim and high comp motor 9.3.1 but we have 94 up here all so useing the lex setup as well
all i did was drop my base timing down to 10 in stead of 12
dyno my car but boost control broke so i pumped out 347 and 398 truq at 11 psi still p;issed my turbo blew befor i got it back on the dyno for a 20 psi run
all so my buddie chad push 20 psi on his 62 to 1 wheel ct26
all i did was drop my base timing down to 10 in stead of 12
dyno my car but boost control broke so i pumped out 347 and 398 truq at 11 psi still p;issed my turbo blew befor i got it back on the dyno for a 20 psi run
all so my buddie chad push 20 psi on his 62 to 1 wheel ct26