Power loss after 5000RPM?? Options

[RockyMountainCel...]

Picked up my first 1995 Celica GT today and after driving it for awhile it really seems to fall on it's face after about 5000RPM.........any ideas why it's doing that? Fuel pump? Bad intake? Injectors? First thing tomorrow I'm removing the intake and cleaning the TB and the intake filter and then a full tank of 93 octane. I'll probably check the spark plugs/gaps while I'm in there, anyone know what the stock gap should be? Only mods it has are a DIY intake and a full catback exhaust.

This post has been edited by RockyMountainCelica: Aug 17, 2010 - 1:20 AM

[mgnt232]

well i only have an ST, but from what im told.. the GT isnt too much different. My engine runs perfect, nothing at all wrong everything new, but i dont have any power past 5k, past 4k really for that matter. I just dont think it (7a at least) is meant for that kind of driving. Maybe with all the things you said, and a header it can get a little more power? but i dont imagine much
3s FTW

[samir0189]

the 5sfe is useless after about 5200 rpm. check the dyno threads stickied at the top to see for yourself. it can be corrected with a set of reground cams. i've noticed a little difference in acceleration after putting in the ebay header, but no documentation for that.

the only difference premium fuel will make is in your wallet, but thats your decision...

[RockyMountainCel...]

the 5sfe is useless after about 5200 rpm. check the dyno threads stickied at the top to see for yourself. it can be corrected with a set of reground cams. i've noticed a little difference in acceleration after putting in the ebay header, but no documentation for that.

the only difference premium fuel will make is in your wallet, but thats your decision...

I found in my civic that i got better MPG and the car ran smoother on premium, would the same not be true with my Celica? It does already have 285,000km(177,090miles) and that alone I figure would make it worth while to run premium.

[samir0189]

if you are in the rocky mountain area as your name implies, you all get fuel with a lower AKI because of your elevation, and it has been shown to provide the same performance as the higher octane we receive at lower altitude, however i suppose it is plausible that you notice an effect, based on your elevation.

edit: anyway, at 5000+ rpm, gas mileage goes out the door, and the engine is only designed to make X power on the fuel it was designed for. .. high octane wont help the 5sfe's mechanical inabilities.... but once again, its your $. im not gonna argue.

This post has been edited by samir0189: Aug 17, 2010 - 1:46 AM

[RockyMountainCel...]

if you are in the rocky mountain area as your name implies, you all get fuel with a lower AKI because of your elevation, and it has been shown to provide the same performance as the higher octane we receive at lower altitude, however i suppose it is plausible that you notice an effect, based on your elevation.

edit: anyway, at 5000+ rpm, gas mileage goes out the door, and the engine is only designed to make X power on the fuel it was designed for. .. high octane wont help the 5sfe's mechanical inabilities.... but once again, its your $. im not gonna argue.

fair enough, i appreciate any and all input as this is a new car to me.

This post has been edited by RockyMountainCelica: Aug 17, 2010 - 2:03 AM

[stl95celica]

My GT did the same. But when i put my ebay header an short ram intake on it goes to 6k in the power band

[mak5603]

The 5sfe's max torque is at 5400 RPMs

[RockyMountainCel...]

The 5sfe's max torque is at 5400 RPMs

yea i'm still learning the shift points, i really got shift quickly out of 1st but i keep forgetting and riding it up for nothing, lol I'm used redlining my civic.

[richee3]

Running a higher octane fuel won't do anything for power. It just keeps the fuel from detonating too soon, which keeps the engine from knocking. It's useless unless your engine is high compression or boosted. A stock 5S will do fine on regular fuel and save you ~$5 per fill-up. The 5S is definitely not a performance motor. Just an economy engine that happens to take to boost well. (Hint hint.)