How Much Boost??

[Mitsu725]

How much boost can i run on stock internals, with an EVO III 16g, i got the walbro 255 HO Fuel Pump and the aeromotive FPR, but im on stock injectors, Just want to know the highest amount of boost i can run without blowing her up??

 

[kpt4321]

Read this article I wrote on engine limits.

http://www.dsmtuners.com/forums/showthread.php?t=96677

 

[KPWSerpiente]

kpt, your article in no way or shape helped him.

mitsu725, with stock injectors I wouldn't run more than 15 lbs. I don't know if you have a way of checking injector duty cycles but I would keep them below 80%. When you finally do get larger than stock injectors (I'd go with 650's but 550's will be fine with that turbo) you will probably be able to run 20lbs on pump gas with some decent tuning and 25 or more on racegas. You might risk blowing the headgasket with higher boost levels like that, a nice mitsu metal one would be good to have, but your bottom end is probably never going to be in danger with just a 16g.

-T

 

[SiNiST3R]

i am pretyt much in the same boat, BUT i have no FPR, but i do have the 550s and SAFC trying to figure out mu boost also i was running 15psi when i had the stock injectors

 

[1fast97gsx]

bump base pressure up a few psi and run 17 psi of boost ... no more though. I ran 17 psi with a perfect timing curve on stock injectors back in the 16g days.

 

[Mitsu725]

Well friday i was an idiot and getting ready to race so i turned up the boost 2 19 lbs and that was incredible but i turned it back down to 15 to drive around with but when i ran again i turned it up to 17 lbs but no more, yeah i have some of the supporting mods, i got the walbro 255 HP and i have the aeromotive FPR, but im still on stock injectors and no front mount and i dont feel like blowing the head gasket so im gonna chill with that.

 

[SiNiST3R]

Iam running 18psi i guess thats about right i have it turned for 18, i Don't have a FPR yet though, but i have all the others supporting mods ie 550s,safc,255...

 

[Bd1000Eclipse]

kpt, your article in no way or shape helped him.



-T

Odd... I learned a lot from his article. I guess maybe i should explain it to you since you cant seem to understand it. He was stating that can't just say "this engine will blow up at x amount of boost" because that is stupid. His car could give at 15lbs if he doesnt know how to tune or the motor isnt in good shape. You can base a motor going out just on boost. His bottom end will never be in danger with a 16g? How do you figure? Poor tuning could equal detonation witch will take any bottom end out. You are telling him to tune based on injector duty cycles? You really shouldnt be giving advice. Tune by knock, timing and egt's. Since you 2nd gen guys cant see knock watch the timing curve and tune/ run boost accordinly. Once again Kpt (kyle right?) Was correct. Follow his advice.