how much boost with 91 octane?
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So my question is, whats the most boost people are pushing with 91 octane on stock internal? is there no way to boost higher with 91 octane? And yeah i know if you lowwer the compresion you can boost more.
Bigger injectors?
of course with hondata or some sorta of Fuel managment would come into play.
Marc
[Modified by Cramerox, 4:08 PM 10/23/2002]
Bigger injectors?
of course with hondata or some sorta of Fuel managment would come into play.
Marc
[Modified by Cramerox, 4:08 PM 10/23/2002]
I'm not sure how much this will apply to your car, but I'm running 20 psi on 91 octane (the best we get in Utah). Lowered compression helps, of course (I'm running about 7.5:1) but I also credit a plan of attack to eliminate every potential source of detonation: I run spark plugs a few temp ranges colder than stock (Champion RN9YCs), I use a <ahem> large intercooler to bring my charge temp as low as I can get it, etc.
As you decide to go for more power, raise your boost only ONE pound at a time. After each increase, carefully examine your plugs for any tiny signs of detonation. If they say all is well, go up one more pound and repeat; if you see anything bad then back off a pound or two and stand pat. If you do this, you'll find your car's limit without fragging your engine.
As you decide to go for more power, raise your boost only ONE pound at a time. After each increase, carefully examine your plugs for any tiny signs of detonation. If they say all is well, go up one more pound and repeat; if you see anything bad then back off a pound or two and stand pat. If you do this, you'll find your car's limit without fragging your engine.
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see i know your able to run 20 psi on 91 gas because the compresion is lower than mine. But lets say your car had a compresion of 10:1 would you be able to still run 20 psi on 91 octane? Im thinking no.
Basically what im trying to get at is. i want to keep my cars compresion stock when i eventually upgrade my pistons. But i also want to boost 14lbs. Im just trying to figure out if there is a way to do that running only 91 octane.
Basically what im trying to get at is. i want to keep my cars compresion stock when i eventually upgrade my pistons. But i also want to boost 14lbs. Im just trying to figure out if there is a way to do that running only 91 octane.
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Could you run 20 psi with that compression? I doubt it. Could you run 14? Maybe, especially with a *fabulous* intercooler. (I've run 14 psi with no intercooler at all on 8.1:1 compression, even with this crap gas.) Eliminate all other reasons for your engine to detonate, then go up one pound at a time and see what happens.
For the record, your seat-of-the-pants sensation will not notice a drop of half a point of compression... but I'm sure you'll enjoy the few extra pounds of boost this lets you run! If you're gonna be shopping for new slugs anyway....
For the record, your seat-of-the-pants sensation will not notice a drop of half a point of compression... but I'm sure you'll enjoy the few extra pounds of boost this lets you run! If you're gonna be shopping for new slugs anyway....
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What should I be looking for when I 'carefully examine my plugs for signs of detonation'?
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so turbo minivan, is there a rule or some math conversion to determin how much boost i can increase for a certain amount of compresion i decrease?
marc
marc
see i know your able to run 20 psi on 91 gas because the compresion is lower than mine. But lets say your car had a compresion of 10:1 would you be able to still run 20 psi on 91 octane? Im thinking no.
Basically what im trying to get at is. i want to keep my cars compresion stock when i eventually upgrade my pistons. But i also want to boost 14lbs. Im just trying to figure out if there is a way to do that running only 91 octane.
Basically what im trying to get at is. i want to keep my cars compresion stock when i eventually upgrade my pistons. But i also want to boost 14lbs. Im just trying to figure out if there is a way to do that running only 91 octane.
NO, thier is really no way to run that kind of power or that kind of boost safely
on 91, or at least it's not a good idea.
Don't **** around with something that expensive, run race fuel and then do what turbominivan was sayin.
with 91 you can go 14lbs but its not as safe compared to race fuel. i wouldnt go no more then 12lbs on a stock motor. just make sure you have the right amount of fuel, ignition, a proper fuel management, and maybe even a head gasket. then you might beable to run 14lbs but 12lbs for sure.
if you get a head gasket from inline pro it drops your compression 1 whole, so if your 10:1 its goona be 9:1.
if you get a head gasket from inline pro it drops your compression 1 whole, so if your 10:1 its goona be 9:1.
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thats just the info i needed to know.....btw how much are you boosting? 91 octane? setup?
with 91 you can go 14lbs but its not as safe compared to race fuel. i wouldnt go no more then 12lbs on a stock motor. just make sure you have the right amount of fuel, ignition, a proper fuel management, and maybe even a head gasket. then you might beable to run 14lbs but 12lbs for sure.
if you get a head gasket from inline pro it drops your compression 1 whole, so if your 10:1 its goona be 9:1.
if you get a head gasket from inline pro it drops your compression 1 whole, so if your 10:1 its goona be 9:1.
water injection is a poor excuse for tunning.
[Modified by blufke, 10:17 PM 11/9/2002]
thats just the info i needed to know.....btw how much are you boosting? 91 octane? setup?
setup:
b18c1 block with crower rods, arias piston, benson sleeve
b16a head stainless steel valves, custom valve springs, titanium retainers, port and polish
t3/t04e .60 trim, drag intercooler and pipping, 440 injectors, blitz bov, bbk pump, hondata 3b. bunch of others too, but to long to list.
I was runnning 4 bar on 91 octane... then my wife elbowed me in her sleep and i woke up...
I think the max depends on tuneing... keep going til you dont hear detonation...
max boost depends on a lot of things...
14psi on an eclipse on pump gas is ok, but its a small *** turbo... 14psi on a huge turbo would mean more air, nneed for more fuel etc...
have it tuned really well... and just aim for max boost tuned on what gas you have.
I think the max depends on tuneing... keep going til you dont hear detonation...
max boost depends on a lot of things...
14psi on an eclipse on pump gas is ok, but its a small *** turbo... 14psi on a huge turbo would mean more air, nneed for more fuel etc...
have it tuned really well... and just aim for max boost tuned on what gas you have.
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