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-   -   Ways for faster revving when blipping the throttle?? (https://www.ft86club.com/forums/showthread.php?t=67518)

glamcem 06-06-2014 09:13 PM

Ways for faster revving when blipping the throttle??
 
I am not sure if this is the parasitic loss due to supercharger but I could definitely notice the slower revving feel during the down shift rev matching since the clutch pedal is depressed during the down shift rev matching all I think of is the lighter crank pulley or maybe an underdrive pulley?



Any other suggestions?

It's a very critical safety issue in my opinion and surprisingly I couldn't find anyone mentioned it here

dradernh 06-06-2014 10:17 PM

Lightweight clutch?

MINOCIN 06-06-2014 10:39 PM

I know what you mean. I immediately felt the same thing after my Innovate SC kit was installed. The slow revs that I got when trying to blip the throttle on a downshift reminded me of when I first purchased my car and the engine hadn't broken in yet. My first thoughts were to get a set of lightweight pulleys and a lightweight flywheel. I'm going to hold off on the pulley set for a while, but I definitely want to switch to a lighter flywheel.

D K 06-06-2014 10:48 PM

Quote:

Originally Posted by dradernh (Post 1783312)
Lightweight clutch?

^^^^

That

thatfilipinoguy 06-06-2014 11:20 PM

You'd want a light weight flywheel...the clutch has nothing to do with the rotation of the crank when you are rev matching.

glamcem 06-06-2014 11:25 PM

I'm not sure how light flywheel/clutch combo can help when clutch pedal is depressed simply because there is no pressure on them ..I can understand when on the gear iit should definitely help the engine revs freely ..I think same can be said for the drive shaft too..so the only thing one my mind is the lighter pulleys or other methods that reduce the parasitic load/loss.. I don't have any experience with underdrive pulleys or lighter pulleys..

SmsAlSuwaidi 06-06-2014 11:26 PM

You'd want a very light flywheel, i have a 10.5 pound one and my revs jump to over 3 with slight blips


[ame="https://www.youtube.com/watch?v=A_1c8bcudag"]The joy of a 10.5 pound flywheel - Turbo Frs - YouTube[/ame]

glamcem 06-06-2014 11:31 PM

Quote:

Originally Posted by thatfilipinoguy (Post 1783387)
You'd want a light weight flywheel...the clutch has nothing to do with the rotation of the crank when you are rev matching.

That's what I thought, how can the lightweight flywheel affect the engine speed when clutch is not engaged ? I always thought it would be the same with lighter clutch..

The bad thing is since Kraftwerks kit uses a unique crank hub adapter that goes over the OEM pulley so I'm not sure if I can use an aftermarket one.. One of the owners had his kit installed by a shop but I think it's modified

glamcem 06-06-2014 11:36 PM

Quote:

Originally Posted by SmsAlSuwaidi (Post 1783392)
You'd want a very light flywheel, i have a 10.5 pound one and my revs jump to over 3 with slight blips


The joy of a 10.5 pound flywheel - Turbo Frs - YouTube

Thanks for the video, I wonder how it would rev with a SC since the load on the belt should be one of the main factors for slow revving..

gramicci101 06-07-2014 12:08 AM

Quote:

Originally Posted by glamcem (Post 1783398)
That's what I thought, how can the lightweight flywheel affect the engine speed when clutch is not engaged ? I always thought it would be the same with lighter clutch..

The flywheel is on the engine side of things, so even if the clutch is disengaged the flywheel is still spinning. The OEM flywheel is heavy by design. This creates significant inertia once it's spinning, so if you're less than smooth with the clutch it doesn't bog the engine. The downside is that there's more weight to spin and more inertia to overcome when you want to change engine speed. Blipping the throttle on a downshift, say.

A lighter flywheel is better in some ways, as there is less rotational mass and less inertia to overcome when changing engine speed, but at the same time it's less tolerant to marginal shift technique because there is less inertia. Some manufacturers (Exedy, I think) will lighten the flywheel while trying to keep most of the remaining weight around the outside of the wheel. This helps to maintain the spinning inertia, while still removing weight and rotational mass.

glamcem 06-07-2014 12:27 AM

Quote:

Originally Posted by Monogram (Post 1783448)
"Blipping" the throttle is not a constant. Learn to time the "blip", learn throttle control where you do not completely let off of the throttle on downshifts, learn to finesse the throttle when braking rather than clubbing it, learn to double-clutch while braking and finessing the throttle.

Just my opinion.

Well, It's not my technique ;) but thanks for the lesson

glamcem 06-07-2014 12:34 AM

Quote:

Originally Posted by gramicci101 (Post 1783456)
The flywheel is on the engine side of things, so even if the clutch is disengaged the flywheel is still spinning. The OEM flywheel is heavy by design. This creates significant inertia once it's spinning, so if you're less than smooth with the clutch it doesn't bog the engine. The downside is that there's more weight to spin and more inertia to overcome when you want to change engine speed. Blipping the throttle on a downshift, say.

A lighter flywheel is better in some ways, as there is less rotational mass and less inertia to overcome when changing engine speed, but at the same time it's less tolerant to marginal shift technique because there is less inertia. Some manufacturers (Exedy, I think) will lighten the flywheel while trying to keep most of the remaining weight around the outside of the wheel. This helps to maintain the spinning inertia, while still removing weight and rotational mass.

If that's the case I think my only option is to change the flywheel (most likely with an Exedy Stage 1kit)
I actually knew the disadvantages of lighter flywheel but just didn't know it would still help the faster revving when clutch is disengaged.
Thanks again

BTW, I also ordered Cusco accelerator pedal so maybe it may help a little bit..ugh

tbertran 06-07-2014 02:19 AM

Stiffer motor mounts would probably help too. Less slack under load. More NVH though...

D K 06-07-2014 02:42 AM

Quote:

Originally Posted by glamcem (Post 1783398)
That's what I thought, how can the lightweight flywheel affect the engine speed when clutch is not engaged ?



Oh gawd:confused0068:


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