How high can we boost on the stock fuel system?
Apr 15, 2003, 01:11 PM
#1
Evolved Member
Thread Starter
iTrader: (3)
Join Date: Mar 2003
Location: Turkey Town (Gobble-Gobble)
Posts: 1,188
Likes: 0
Received 1 Like
on
1 Post
How high can we boost on the stock fuel system?
Hey guys just curious how high we can boost on the stock fuel system with zero mods to fuel, just running 100 octane and turning up the boost.
Apr 15, 2003, 02:04 PM
#2
Newbie
Join Date: Apr 2003
Posts: 89
Likes: 0
Received 0 Likes
on
0 Posts
That's a tough question. The octane you run is going to be a big desciding factor. The thing is if you set the psi to match the octane your running then you better run that octane all the time. If you don't then your going to lean out the car and do all kinds of damage. Some on this forum are even speculating if you can run 19.5 to redline. I think you probably can, but I doubt you will get much higher than 21 psi. Maybe 22. But I think you would just be unwise to go any higher than stock in the psi. Especially with out knowing what your doing. I posted something in another topic about how psi effects compression.
https://www.evolutionm.net/forums/sh...threadid=20133
Also check out this link:
https://www.evolutionm.net/forums/sh...threadid=19747
https://www.evolutionm.net/forums/sh...threadid=20133
Also check out this link:
https://www.evolutionm.net/forums/sh...threadid=19747
Apr 15, 2003, 02:11 PM
#3
Evolved Member
Thread Starter
iTrader: (3)
Join Date: Mar 2003
Location: Turkey Town (Gobble-Gobble)
Posts: 1,188
Likes: 0
Received 1 Like
on
1 Post
well i'm not worried about not knowing what i'm doing... I'm jsut curious as to how high we can go on this car becasue the stock fuel system runs WAY to rich... so rather then leaning the fuel out with a fuel controller waht would raising the boost in the highend do to the fuel maps... my boost controller is on order i'm jsut itching to mess with this car
Apr 15, 2003, 02:16 PM
#4
Evolved Member
iTrader: (17)
Join Date: Feb 2003
Location: Castle Rock, CO
Posts: 1,546
Likes: 0
Received 0 Likes
on
0 Posts
I have the Greddy Profec B spec set to 22psi all the way to redline. Runs great. 24 to 26 is where I encountered fuel cut. S-AFC, downpipe, test pipe, and exhaust are on the way. May keep it at 22psi after all the mods go in, but I may dop to 20psi.
Apr 15, 2003, 02:17 PM
#5
Newbie
Join Date: Apr 2003
Posts: 89
Likes: 0
Received 0 Likes
on
0 Posts
I wouldnt even want to guess to be honest. Too much damage can come from it. I don't have an evo 
But like I said I would be pretty darn careful trying to up the boost.
Anyone else want to chime in? Thats has actually up'd the psi on the evo 8?
But like I said I would be pretty darn careful trying to up the boost. Anyone else want to chime in? Thats has actually up'd the psi on the evo 8?
Apr 15, 2003, 02:21 PM
#6
Evolved Member
Thread Starter
iTrader: (3)
Join Date: Mar 2003
Location: Turkey Town (Gobble-Gobble)
Posts: 1,188
Likes: 0
Received 1 Like
on
1 Post
Stvbreal what does your A/F look like, are you logging EGT temps? Is your car completely stock other then the Boost controller?
And i'm not looking for guesses, just people who have tested
And i'm not looking for guesses, just people who have tested
Apr 15, 2003, 02:26 PM
#7
I do not know the correct answer to the question, at the moment but: answer these questions:
1. size of your injectors
2. maximum amount of boost your turbo can handle before it becomes inefficient and pumps out hot air.
3. amount of fuel your fuel pump can pump out.
your questions can be better answered after putting these few variables together.
daimon
1. size of your injectors
2. maximum amount of boost your turbo can handle before it becomes inefficient and pumps out hot air.
3. amount of fuel your fuel pump can pump out.
your questions can be better answered after putting these few variables together.
daimon
Trending Topics
Apr 15, 2003, 02:30 PM
#8
Evolved Member
Thread Starter
iTrader: (3)
Join Date: Mar 2003
Location: Turkey Town (Gobble-Gobble)
Posts: 1,188
Likes: 0
Received 1 Like
on
1 Post
Uhhdid I forget to mention stock evo?
I think stock specs are like
550 injectors (around that size)
24-26psi (people have said the turbo likes to be in that psi)
and beats the hell out of me...
Actually i'd rather go with actually logs then a mathamatical formula
I think stock specs are like
550 injectors (around that size)
24-26psi (people have said the turbo likes to be in that psi)
and beats the hell out of me...
Actually i'd rather go with actually logs then a mathamatical formula
Apr 15, 2003, 02:52 PM
#9
True logs are better:
i was going to compare it to 2 liter motors (sr20det) doing the same. 550's are known to be good for 350- 400 hp, if your intercooler can flow that much air and the fuel pump holds up 21 punds would not be a problem.
Now about the turbo holding 24-26, that i pretty damn impressive for a stock turbo. =)
i was going to compare it to 2 liter motors (sr20det) doing the same. 550's are known to be good for 350- 400 hp, if your intercooler can flow that much air and the fuel pump holds up 21 punds would not be a problem.
Now about the turbo holding 24-26, that i pretty damn impressive for a stock turbo. =)
Apr 15, 2003, 03:05 PM
#11
Evolved Member
iTrader: (17)
Join Date: Feb 2003
Location: Castle Rock, CO
Posts: 1,546
Likes: 0
Received 0 Likes
on
0 Posts
The ECU will prevent the engine from blowing up so dont worry about cranking the psi but don't go overboard, use common sense. I'm not gonna crank it 30 when I know I hit fule cut a 25 to 26. As far as the EGT temp and A/F reading I have none. I only have the BC on right now. All the other stuff is coming this week. After Ig et it all isntalled I will get the shop to tune the S-AFC to spec.
Apr 15, 2003, 03:10 PM
#12
Newbie
Join Date: Apr 2003
Posts: 89
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by rogue
True logs are better:
i was going to compare it to 2 liter motors (sr20det) doing the same. 550's are known to be good for 350- 400 hp, if your intercooler can flow that much air and the fuel pump holds up 21 punds would not be a problem.
Now about the turbo holding 24-26, that i pretty damn impressive for a stock turbo. =)
True logs are better:
i was going to compare it to 2 liter motors (sr20det) doing the same. 550's are known to be good for 350- 400 hp, if your intercooler can flow that much air and the fuel pump holds up 21 punds would not be a problem.
Now about the turbo holding 24-26, that i pretty damn impressive for a stock turbo. =)
Apr 15, 2003, 03:22 PM
#13
Evolved Member
Thread Starter
iTrader: (3)
Join Date: Mar 2003
Location: Turkey Town (Gobble-Gobble)
Posts: 1,188
Likes: 0
Received 1 Like
on
1 Post
4G63 motors are CRAZY....
I've been told and i've read from a number of people (who own shops) that the motor will hold up to about 25 psi, after 26-27 the rods will let go. The old Eclipse motors would hold 21psi then the head bolts would stretch, but internals never let go. Internals on the eclipse let go at about, I tihnk it was 25psi
I've been told and i've read from a number of people (who own shops) that the motor will hold up to about 25 psi, after 26-27 the rods will let go. The old Eclipse motors would hold 21psi then the head bolts would stretch, but internals never let go. Internals on the eclipse let go at about, I tihnk it was 25psi
I am not expert.. but I don't want anyone doing anything stupid and blowing their motors
Apr 15, 2003, 04:07 PM
#15
I have run 26psi on my 4G63. With the stock Evo turbo, chances are that you would only get hot air at that boost level.
With all this talk of damaging engines due to overboosting or modifying, or tuning, have you ever actually heard of someone damaging an Evo engine? If so, what were the parameters?
With all this talk of damaging engines due to overboosting or modifying, or tuning, have you ever actually heard of someone damaging an Evo engine? If so, what were the parameters?