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Safe boost?!?!?!?!

4764 Views 16 Replies 6 Participants Last post by  OMASERONE
I am buying a turbosmart manual boost controller and a greddy type s bov (the one modded by RRE) and was just wondering before i do something too stupid :p whats the absolute most boost i can safley run on stock internals and all that ( only mods are a buschur intake filter, downpipe, catback..and of course the greddy bov when i get it...) I know not to run too much boost...i was just wondering if the car is cabable of say as a random number around 24psi...or is it safe to run 22 or 21...or what. I know i cant just turn the boost up to 30 and go...i was just wondering what anyone was running on stock pistons, rods, retainers, valves and springs..etc. Sorry if this is a dumb question...ha. but thanks.
:D
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For us in CA it's more of a matter of octane. For me, at 21-22psi., I get a little bit of knock between 4000-5500 RPM's. It's so small too, just a 1-2 degree timing pull. I've dropped in some BPR7ES's, but I need to do some logging to see if that took care of it.
I've dropped in some BPR7ES's
What are those??
Spark plugs that are one range colder than stock. Meaning they will disapate more heat in the cylinder than the stock plugs.
turbolarry said:
Spark plugs that are one range colder than stock. Meaning they will disapate more heat in the cylinder than the stock plugs.
7's are the stock heat range for EVO's, they are one range colder than stock for the DSM's. :)

Keith
okay, so if i were to experience a small amount of knock...i could go to spark plugs that are one range cooler and that should (ideally) take care of it?? also, what would be the most boost i should run if i have not tuned my ecu or fuel settings at all??
turbosmartevo8 said:
okay, so if i were to experience a small amount of knock...i could go to spark plugs that are one range cooler and that should (ideally) take care of it?? also, what would be the most boost i should run if i have not tuned my ecu or fuel settings at all??

No, no. You only have 91oct, so you should run 20psi daily...at most let it spike to 21, but anything more than that and you will just lose power from knocking. Regardless of tuning or mods, you should only run higher boost on higher octane, or if you get alky injection.
sounds good...say i go to the drag strip and run race gas...whats the highest i should run there without A/F tuning mods??
Fourdoor said:
7's are the stock heat range for EVO's, they are one range colder than stock for the DSM's. :)

Keith

:eek:
Thanks Keith. I really did sell my Eclipse and I'm not living in the past. I'm off to the auto parts store.
:eek:
turbosmartevo8 said:
sounds good...say i go to the drag strip and run race gas...whats the highest i should run there without A/F tuning mods??
You shouldn't mess with your boost and race gas without A/F tuning mods. When you can tune for the higher octane and boost, I will then tell you what boost level is recommended.
Im just so new to this tuning thing...i could probably do basic stuff ( i.e. following the guide...) but wouldnt know what to do when i got different mods and what not..i just need someone to be able to kinda explain it to me. I dont want to have other people tune my car for me all the time...but to have someone kinda help me along the way. I understand the concept of it...but i guess im having trouble grasping the mechanics. Thats why im bugging you guys on the forums :p haha.
turbosmartevo8 said:
Thats why im bugging you guys on the forums :p haha.

There is no bugging. Don't even trip. :thumb: We're here to share information. Please don't be affaid to ask questions. You won't get any; "Use the seach" or "That's a newbie question" kind of responses. Chances are there's twenty other Evo owners wondering the same thing.
i thought the amount of boost you were able to run was based on what octane gas you could run..the higher octane you could burn..the higher boost you could run... how would i tune for different octanes...would i have to go richer or leaner?? and thanks larry. :thumb:
turbosmartevo8 said:
i thought the amount of boost you were able to run was based on what octane gas you could run..the higher octane you could burn..the higher boost you could run... how would i tune for different octanes...would i have to go richer or leaner?? and thanks larry. :thumb:
Add the fuel.
Reset the ECU.
Raise the boost a little at a time, log runs in between, and make sure everything is safe.
As long as everything remains within safe parameters (no knock), keep raising the boost to your desired level. Once the boost is set, follow our guide, and add or subtract fuel where needed.
Keep your eye on the timing/look for any signs of knock.
turbolarry said:
:eek:
Thanks Keith. I really did sell my Eclipse and I'm not living in the past. I'm off to the auto parts store.
:eek:
Just so you know, I would not run 8's in an evolution.... you will be fouling the plugs all the time. The 7's work great.

Keith
21-22 psi should be the max boost on 91. On the dyno with 101 octane, we've pushed my car to 28 psi and was making lots of power. But I wouldn't recommend going past 25 psi without at least replacing head studs.
yea for me in nevada we get 91 oct . I will only spike at 21-22 psi and taper down to 19- 19.5 at redline. And thats at WOT in 4th and 5th gear some say to let it spike to 23 psi in 5th cause mine is an 2005, but they are wrong 22 psi max on 91 trust me :dsm:
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