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Feels Heavier To Press Accelerator

seriesII

By seriesII,
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seriesII Mentor

seriesII

Posted
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hey all, this may be something basic, but all off a sudden, now when i press my Accelerator it feels heavier, like i need to push it harder, i did only notice this when i got a heavey duty clutch, but that was 6 months ago and im use to it now, i never installed a new flywheel, and i know i have to replce my tailshalf soon, but from what i know, it should cause a shaking if tailshaft is about to die and is sliping..

my turbo and forced induction parts seem ok, and sounds good while spooling,. the car goes when i put my foot down, dont feel any lag or delay, just feels harder to press the Accelerator, i have tryed this on a cold and hot night, still same effect, is this possbile?, or any idea what it may be would be awseome. thanx

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BHDave Grand Master

BHDave

Posted
Posted

Check the cable moves freely, check the throttle body, check that nothing is jamming against the pedal under the dash and that the mounts are ok and moving freely.

The weight of the pedal is unrelated to anything else on the car.

seriesII Mentor

seriesII

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  • Author
Posted (edited)

sweet. thanx for the tips, ima try this in the morning... :P

a new clutch sorta makes your accelerator pedal harder i found, need to give it a little more of a push due to a hevey duty clutch.. but now it feels like i need to push a little more heaveir, i thought it was my tires, so i checked the psi and was fine, but still feels like its doing this.. feels weird

Edited by seriesII
seriesII Mentor

seriesII

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Posted

yeah, niether did i, maby im wrong, but yeah, a couple of guys who work on my car, say that once you install a heavey duty clutch you need to give it a little more gas as the clutch is more weight then the stock one.. maby im wrong?, but sounds right, and when i got in a stock skyline with a heavey clutch i had to give alot more gas due to a heavier clutch.. might not notice the difference in clutch if your car has a fair bit of power. but i could be wrong hey :P

Godzilla32 Veteran

Godzilla32

Posted
Posted

It could be a sticky accelerator cable, try removing the cable from the throttle body accelerator drum and working it with no other load. If it feels tight then thats your problem. You can use something like spray grease or wd40 to free it up.

The clutch pedal and accelerator pedal are completely unrelated. The only thing that can get heavier with a new heavy duty clutch is the clutch pedal. All i can think of is maybe they were meaning that with a heavier clutch you need to give it more revs to stop it from stalling?? Who knows...

mad082 Grand Master

mad082

Posted
Posted

there is no way the clutch can affect the throttle cable. i'd say that the cable is either squashed from the install of the clutch, starting to fray inside the casing, or just got some gunk making it sticky.

and you shouldn't have to give it more gas to accelerate. you may have to give it more gas to launch the car as the heavier clutch won't slip as much, resulting in bogging it down, but once you are going there is no difference. and a heavier clutch doesn't really weigh any more than a stock clutch. it just has stiffer springs. it will weigh a fraction more due to the extra material needed to get the stiffer springs, but it is a tiny amount.

when they talk about the weights of clutches they mean the clamp weight. how hard the pressure plate pushes the clutch plate against the flywheel.

seriesII Mentor

seriesII

Posted
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Posted

mad082: hey, thanx for clearing that up with me.. i felt it today. it was weird.. felt light at one stage, then a couple second later, after my foot was on, felt heavey again.. still checking for things that may be catching.. thanx for the help tho..

RANDY Veteran

RANDY

Posted
Posted

Yer... I think when they said "you need to give it more gas", they meant you had to get the revvs up a bit higher so you don't stall when the clutch grabs. It's harder to make a button clutch "slip" when you start moving.

Definately get the cable sorted. Even disconnect it from the pedal, then have someone inspect the engine-bay side, while you pull on it. Disconnect the throttle body side and do the reverse. If that snaps while driving, you could be stranded somewhere.

While the cable is off the throttle, check that you can open the throttle by hand, and that it's smooth. The spring is not progressive rate from memory. It should be pretty linear all the way through.

MBS206 Grand Master

MBS206

Posted
Posted
Yer... I think when they said "you need to give it more gas", they meant you had to get the revvs up a bit higher so you don't stall when the clutch grabs. It's harder to make a button clutch "slip" when you start moving.

Absolute crap.

Mines easy as all hell to slip.

Button clutch, 1250 clamp load. Barely needs any throttle to get it moving. Rolls off the mark with basically no more then 1000RPM...

Drives like stock really... Well, for me anyway.

Just need skill + practice to slip a button clutch.

Godzilla32 Veteran

Godzilla32

Posted
Posted

When you say 1250 i assume your talking in pounds? Thats light as, mine is 3000 pounds (1800lbs stock). Its also a single plate from Jim berry and its marginally heavier than stock to use. Its not all about diaphram tension.

After hearing your pedal changes you should look at the hydraulics to make sure either the slave cylinder or master cylinder arent leaking or in the case of the slave corroded and sticky...

RANDY Veteran

RANDY

Posted
Posted
Absolute crap.

Mines easy as all hell to slip.

Button clutch, 1250 clamp load. Barely needs any throttle to get it moving. Rolls off the mark with basically no more then 1000RPM...

Drives like stock really... Well, for me anyway.

Just need skill + practice to slip a button clutch.

Heh... well.. My R32 GTR mate installed a Jim Berry special, and there's something like 2mm of play before it completely clamps up! Even the dyno operators stalled it when they moved it from the driveway onto the rollers. It's MUCH more fussy than my heavy duty Daikin clutch.

But anyway... back to the topic of accelerator pedals, not clutch pedals eh? :O

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