sr20det sputtering under raised boost level
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sr20det sputtering under raised boost level
just wondering if anyone else has run into this, or any suggestions for a potential quick fix. here's the situation- runs perfectly fine at 10 lbs boost pressure; no hesitation, sputtering, nothing. but once i raise the boost to 14.5 lbs, it sputters. nothing really obnoxious, but i know it's not supposed to run like that. i also smell fuel real strong... not like the rich smell i've almost gotten used to, this smell is like pure gasoline. i haven't changed the plugs since i got the car in august, and it could probably use a new fuel filter as well, but i'm just sort of curious as to why it doesn't act up until i raise the boost. btw this is a very basic setup, all stock save for exhaust, fmic, and an aftermarket mine's vx-rom tuned ecu. my boost controller is a greddy profec b, if that helps any.
Last edited by blackout; 02-28-2006 at 11:32 AM.
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Re: sr20det sputtering under raised boost level
hm.. 14.5 is a little high i think (the turbo passes its efficiency range at 15). your ebc could be overboosting. i ran into a similar problem with my old sr, it would sputter/bog at peak boost, and when it tapered off and held, it was fine.
basically, try running it at 13psi, if you have the same problem. then you have a big fuel issue. SR's as it is run rich, so grab an SAFC =P
in all honesty, theres no point in pushing past 12psi on that setup. the stock wastegate cannot handle past that to my knowledge (maybe even less, i didnt pay much attention to it).
sorry for the jumbled post, at work and my mind is fried.
basically, try running it at 13psi, if you have the same problem. then you have a big fuel issue. SR's as it is run rich, so grab an SAFC =P
in all honesty, theres no point in pushing past 12psi on that setup. the stock wastegate cannot handle past that to my knowledge (maybe even less, i didnt pay much attention to it).
sorry for the jumbled post, at work and my mind is fried.
Last edited by Junon; 02-28-2006 at 11:39 AM.
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Re: sr20det sputtering under raised boost level
Originally Posted by Junon
hm.. 14.5 is a little high i think (the turbo passes its efficiency range at 15). your ebc could be overboosting. i ran into a similar problem with my old sr, it would sputter/bog at peak boost, and when it tapered off and held, it was fine.
basically, try running it at 13psi, if you have the same problem. then you have a big fuel issue. SR's as it is run rich, so grab an SAFC =P
in all honesty, theres no point in pushing past 12psi on that setup. the stock wastegate cannot handle past that to my knowledge (maybe even less, i didnt pay much attention to it).
sorry for the jumbled post, at work and my mind is fried.
basically, try running it at 13psi, if you have the same problem. then you have a big fuel issue. SR's as it is run rich, so grab an SAFC =P
in all honesty, theres no point in pushing past 12psi on that setup. the stock wastegate cannot handle past that to my knowledge (maybe even less, i didnt pay much attention to it).
sorry for the jumbled post, at work and my mind is fried.
if all else fails then of course i'm going to drop the boost though.
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Re: sr20det sputtering under raised boost level
Definately need to upgrade that fuel pump if you haven't already. The stock 370cc injectors can't keep up with that much boost either. You're running the risk of locking one up.
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Re: sr20det sputtering under raised boost level
Could it be your plugs, are you using NGK BPR7E and gapped at .028
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Re: sr20det sputtering under raised boost level
I've been running 14.7 psi in my SR for a looong time now. Change the plugs to one step colder (heat range 7) and gap them to .028.
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Re: sr20det sputtering under raised boost level
Originally Posted by WarriorBlaZe
Definately need to upgrade that fuel pump if you haven't already. The stock 370cc injectors can't keep up with that much boost either. You're running the risk of locking one up.
Could it be your plugs, are you using NGK BPR7E and gapped at .028
Last edited by blackout; 02-28-2006 at 02:08 PM.
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Re: sr20det sputtering under raised boost level
if its the 100lph, then its a stock replacement, u want the 255lph.
I reccomend changing fuel filter to the 300zx twin turbo fuel filter, and plugs.
I reccomend changing fuel filter to the 300zx twin turbo fuel filter, and plugs.
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Re: sr20det sputtering under raised boost level
Originally Posted by Moriar
if its the 100lph, then its a stock replacement, u want the 255lph.
I reccomend changing fuel filter to the 300zx twin turbo fuel filter, and plugs.
I reccomend changing fuel filter to the 300zx twin turbo fuel filter, and plugs.
i'm wondering if it doesn't already have a z filter... again, thanks for the reminder. all things that will likely be done tomorrow- but definitely before track time sunday.
#10
Re: sr20det sputtering under raised boost level
Mine did that when i raised the boost, it was the spark plug gap. try taking your plugs out and regapping them to something smaller. also, i ran 14-15 psi all day long on my stock turbo/injectors and it was FINE