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Does High PSI Boost Destroy Your Engine? How To Prevent It?

Posted: Tue Jan 16, 2007 12:15 pm
by oped
Hello,

I have been told from all my mates who claim knowledge in turbo's that when you boost your turbo to a higher psi that it destroys your engine.

So boosting from 7 to 15psi would mean a shortened engine life.

Is that true?

And if it is, what can you do to prevent or stop it?

Thanks

Posted: Tue Jan 16, 2007 12:21 pm
by Alspos
Boost doesn't kill an engine on it's own, poor tuning helps.

Forged pistons will allow more boost to be used (compared to stock pistons) as long as it's tuned correctly.

Posted: Tue Jan 16, 2007 1:17 pm
by Junkers
Don't raise it over 13 psi if you have an intercooler and don't raise it over 10 psi if you don't. Running 98 ron will help keep it cool aswell.
Raising your boost causes extra heat which can crack pistons etc and with poor tuning like al said, the engine will run lean and get even hotter.

If you decide to raise your boost and find that when you drive it, it has a sudden cut out or 'jolt' feeling, thats your ecu letting you know your pushing it too far. Sometimes it will cut out before 13psi but there are ways around that.

Posted: Tue Jan 16, 2007 2:10 pm
by Chryzla
inpropper tuning and fatigued components cause failure.

Also all mitsubishis from the 80's have pretty poorly designed heads.. they are usually the first thing to go in my experience

Posted: Tue Jan 16, 2007 11:37 pm
by redzone
hi boost doesnt destroy engines, poor tuning does (lean outs, detonation/pinging etc)..

its a complicated question to answer really, i mean running higher boost makes it easier for these tuning mishaps to happen so for example people say:

" my engine blew coz i was running too much boost"

whereas they should say:

"i blew up my engine coz i'm an idiot and didnt hear it pinging its tits off on 15 psi coz i was a cheapskate at last petrol fill and put 91 octane in instead of the 98 its tuned to run"

LOL

Posted: Wed Jan 17, 2007 2:03 am
by oped
Oh, i thought the hi pressure would f*ck things in the engine.
And doing it for along time just roots the crap out of everything.
If its just a heating problem, couldnt you add another radiator or upgrade your engine cooling.

Also, just curios, can you use a intercooler as a radiator. Because I am guessing intercoolers work alot better at cooling air than the radiator.

Posted: Wed Jan 17, 2007 7:44 am
by Alspos
Oh, i thought the hi pressure would f*ck things in the engine.

- Read what was said. Poor tuning and boost will fuck the engine.

And doing it for along time just roots the crap out of everything.

- Same with anything you abuse, it will wear out quicker or break

If its just a heating problem, couldnt you add another radiator or upgrade your engine cooling.

- It's internal combustion chamber heat.

Also, just curios, can you use a intercooler as a radiator. Because I am guessing intercoolers work alot better at cooling air than the radiator.

- It would already be done if they worked better.

Posted: Wed Jan 17, 2007 4:50 pm
by OLD FART
More boost = higher compression = more power = more load on bearings etc = shorter time B tween rebuilds =more $$$ 2 spend :(

Posted: Wed Jan 17, 2007 4:53 pm
by Chryzla
Much to learn my young padawan

Posted: Wed Jan 17, 2007 5:04 pm
by Junkers
redzone wrote:hi boost doesnt destroy engines, poor tuning does (lean outs, detonation/pinging etc)..
So I could run 30 psi through my standard engine as long as I've tunned it properly :wtf:

Posted: Wed Jan 17, 2007 6:13 pm
by RiceThief
Junkers wrote:
redzone wrote:hi boost doesnt destroy engines, poor tuning does (lean outs, detonation/pinging etc)..
So I could run 30 psi through my standard engine as long as I've tunned it properly :wtf:
Technically yes, but with increased boost your detonation threshold is lower so you would have to pull back timing so much that it would run like shit and be far away from your effiency range that you would have less power than a lower boost level.

I think the main point everyone is trying to say is the biggest killer of engines is detonation and lean ratios, rather than boost on its own. You could damage an engine on stock boost if you are running lean or your timing advance is too much that it causes detonation. On the other hand if you keep your air ratios right and the engine doesnt have pinging then running more boost is okay. In the end all engines have a limit on how much load it can handle based on its design.

Posted: Thu Jan 18, 2007 2:42 pm
by oped
And the way to raise that limit is with forged pistons?

Posted: Thu Jan 18, 2007 2:50 pm
by benny
"On the other hand if you keep your air ratios right and the engine doesnt have pinging then running more boost is okay"

there is your answer..

most mild street apps don't need forgies unless its for wank factor to say you have them.

make sure fuel, timing and cooling are up to it and you should be fine

oh and if your car has never had a rebuild (ie it is an 82-86 original motor) don't abuse it and expect it to last even with the right fule/timing/cooling combo

Posted: Thu Jan 18, 2007 3:45 pm
by madeofmilo
benny wrote:"

most mild street apps don't need forgies unless its for wank factor to say you have them.
thats why I am getting them :P....not (borat quote)

Posted: Thu Jan 18, 2007 5:04 pm
by oped
So forged pistons are really non benefitial?