Advice Please Options

[6G96GT]

First thing, I took off my wheel the other day to get a look at my rotor, anyway the car was in 1st gear (parked, engine off) and the e-brake was up all the way. I noticed though that the rotor moved about 1/4" back and forth even in gear with the e-brake on. Is that normal? My brake will hold me on a hill when in neutral.

Second, is there anything I can do to improve torque or low-end power (without turbo, cams, and supercharger). Would some kind of engine/fuel management or intake manifold work do anything at all to improve it?

Finally, my exhaust is vibrating (very annoying) when reducing speed in every gear (at 2000 rpm, it's the worst). I have the header into a flex pipe into a hi-flow cat (shielded) into a welded resonator into my exhaust. It's definitely not the muffler or resonator and I don't 'think' it's the header. When I jacked up the car and started it and had my friend raise and lower the throttle, I didn't hear any vibration or rattle at all.

This post has been edited by 6G96GT: Jun 8, 2009 - 1:50 PM

[Mstoochn]

First thing, I took off my wheel the other day to get a look at my rotor, anyway the car was in 1st gear (parked, engine off) and the e-brake was up all the way. I noticed though that the rotor moved about 1/4" back and forth even in gear with the e-brake on. Is that normal? My brake will hold me on a hill when in neutral.

Second, is there anything I can do to improve torque or low-end power (without turbo, cams, and supercharger). Would some kind of engine/fuel management or intake manifold work do anything at all to improve it?

Finally, my exhaust is vibrating (very annoying) when reducing speed in every gear (at 2000 rpm, it's the worst). I have the header into a flex pipe into a hi-flow cat (shielded) into a welded resonator into my exhaust. It's definitely not the muffler or resonator and I don't 'think' it's the header. When I jacked up the car and started it and had my friend raise and lower the throttle, I didn't hear any vibration or rattle at all.

its possible someone really doesn't like you and threw some loose change into your exhaust.

as for adding some hp, the best thing anyone could probably suggest is an SAFC, although it will significantly reduce the life of your engine. (Super air flow converter) if tuned properly your looking at about 25-30hp. Im not sure why you have a low end torque problem as the 5s-fe as Alot of low end power. my bone stock GT beats 9/10 street cars off a red light

[6G96GT]

That's what I mean, I definitely had more low-end before I switched from the stock mani to the header.

Why would a SAFC reduce the engine life? I thought tuning it would be good.

[Mstoochn]

That's what I mean, I definitely had more low-end before I switched from the stock mani to the header.

Why would a SAFC reduce the engine life? I thought tuning it would be good.

from the factory they are designed to be as economic as possible, for long lasting (5th gen Sseries-Economy Electronic fuel inj.) your pumping more into the engine reducing the life of seals/gaskets/sensors

[fenderdave]

First thing, I took off my wheel the other day to get a look at my rotor, anyway the car was in 1st gear (parked, engine off) and the e-brake was up all the way. I noticed though that the rotor moved about 1/4" back and forth even in gear with the e-brake on. Is that normal? My brake will hold me on a hill when in neutral.

Second, is there anything I can do to improve torque or low-end power (without turbo, cams, and supercharger). Would some kind of engine/fuel management or intake manifold work do anything at all to improve it?

Finally, my exhaust is vibrating (very annoying) when reducing speed in every gear (at 2000 rpm, it's the worst). I have the header into a flex pipe into a hi-flow cat (shielded) into a welded resonator into my exhaust. It's definitely not the muffler or resonator and I don't 'think' it's the header. When I jacked up the car and started it and had my friend raise and lower the throttle, I didn't hear any vibration or rattle at all.

I've had a virating type noise that i only get when i'm moving and at around 2000rpm, I recently had it serviced and they told me my front flex pipe was seriously corroded so im starting to think that this is the source of the noise. Im by no means an expert though, but thought it might help.

[6G96GT]

Thanks for the tip, mine is actually pretty new. I did get it resolved by about 80%. I still have a tiny bit left somewhere but no clue as to where.

[trdproven]

your exhaust flexes pretty good when you put some umphh into the gas pedal. YOu can tell if you open the hood the engine flexes pretty hard on a front wheel drive, use this idea. Sometimes you cannot tell whats going on unless you simulate it, just turning it on and going under won't tell you much. Check if your exhaust bracket is there too.

[stephen_lee]

your exhaust flexes pretty good when you put some umphh into the gas pedal. YOu can tell if you open the hood the engine flexes pretty hard on a front wheel drive, use this idea. Sometimes you cannot tell whats going on unless you simulate it, just turning it on and going under won't tell you much. Check if your exhaust bracket is there too.

true. i've seen my 7a move as much as 3-4 inches while driving w/o a hood. the FWD engine/tranny moves A LOT

[domyz]

That's what I mean, I definitely had more low-end before I switched from the stock mani to the header.

Why would a SAFC reduce the engine life? I thought tuning it would be good.

from the factory they are designed to be as economic as possible, for long lasting (5th gen Sseries-Economy Electronic fuel inj.) your pumping more into the engine reducing the life of seals/gaskets/sensors

If properly tuned it doesn't shorten the life of the engine.
And FYI, SAFC is there to pump less fuel into the engine: Leaning the AFR is the way to gain HP

[presure2]

First thing, I took off my wheel the other day to get a look at my rotor, anyway the car was in 1st gear (parked, engine off) and the e-brake was up all the way. I noticed though that the rotor moved about 1/4" back and forth even in gear with the e-brake on. Is that normal? My brake will hold me on a hill when in neutral.

Second, is there anything I can do to improve torque or low-end power (without turbo, cams, and supercharger). Would some kind of engine/fuel management or intake manifold work do anything at all to improve it?

Finally, my exhaust is vibrating (very annoying) when reducing speed in every gear (at 2000 rpm, it's the worst). I have the header into a flex pipe into a hi-flow cat (shielded) into a welded resonator into my exhaust. It's definitely not the muffler or resonator and I don't 'think' it's the header. When I jacked up the car and started it and had my friend raise and lower the throttle, I didn't hear any vibration or rattle at all.

its possible someone really doesn't like you and threw some loose change into your exhaust.

as for adding some hp, the best thing anyone could probably suggest is an SAFC, although it will significantly reduce the life of your engine. (Super air flow converter) if tuned properly your looking at about 25-30hp. Im not sure why you have a low end torque problem as the 5s-fe as Alot of low end power. my bone stock GT beats 9/10 street cars off a red light

where do you get this info?
20-30whp???
more like 5-10 tops, maybe.
been there, done that.
have you ever tuned a 5sfe, on a dyno?

[6G96GT]

So, a SAFC is good and I can get 5-10 more hp on top of my expecting webcams. This all sounds good to me. By the way, I thought running the fuel lean would lead to detonation. Running it too rich will lead to washing out the cylinders. When I get the webcams and SAFC, I'll head over to the local dyno and pop in a wideband and see if I can find the best a/f mix. Question is...do I need an adjustable fuel pressure reg and fuel pump with a SAFC or not?

I found the vibration by the way. It's on the flex pipe housing at the bottom. One side of it is welded shut and the other seems to have popped open a bit and it rattles. That's got to be the vibration culprit.

[presure2]

So, a SAFC is good and I can get 5-10 more hp on top of my expecting webcams. This all sounds good to me. By the way, I thought running the fuel lean would lead to detonation. Running it too rich will lead to washing out the cylinders. When I get the webcams and SAFC, I'll head over to the local dyno and pop in a wideband and see if I can find the best a/f mix. Question is...do I need an adjustable fuel pressure reg and fuel pump with a SAFC or not?

I found the vibration by the way. It's on the flex pipe housing at the bottom. One side of it is welded shut and the other seems to have popped open a bit and it rattles. That's got to be the vibration culprit.

no need for a FPR or pump.

[6G96GT]

Good to know, thanks!