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> Light weight flywheel?, Street driven 914-6 w/ 2.7l RS spec engine & 901 transaxle
Rufus
post Jun 27 2020, 09:35 PM
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Hi Folks - I just bought this 914-6:

http://www.914world.com/bbs2/index.php?sho...346147&st=0

In planning to add an LSD, I’m also considering a lightweight flywheel.

Will the low end torque of the 2.7l RS spec engine with 901 gearbox (believed to have stock 914-6 ratios), in a stock curb weight ‘70 914-6 be compatible with street driving with a lightweight aluminum flywheel without making starting off too edgy? It has a new street clutch; nothing radical. Also my new 205/55-15 tires are about 5% smaller in diameter than the 185/70-15 1970 OE tires ... and thus provide about 5% greater torque multiplication.

(Why? I did this on my street driven ERA 427 Cobra, and liked the benefits to engine response, and reduced rotating / overall vehicle masses. In that case, even with a triple disc racing clutch, starting from a stop was still pretty manageable.)

Opinions appreciated ...
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stownsen914
post Jun 28 2020, 12:24 PM
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I'd say it depends on whether the car still has the early 2.0 flywheel. The early flywheels are heavier than the later ones, so I'd say it would make sense to go with a lighter one. I think the early 215mm ones are like 15 lbs, while later 225mm ones are a few lbs lighter.

Note that light 215mm flywheels are more expensive due to the more complex shape. I haven't heard of an aluminum version of the 215mm one, but it would be cool if there were.

Another option is an aluminum pressure plate. The aluminum 215mm one is NLA as far as I know, but they turn up in the classifieds from time to time.
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Rufus
post Jun 28 2020, 02:36 PM
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Thanks for your input, stownsen914. About all that’s known is the case is a ‘73T 2.4l 7R, and the transaxle is a 901, “possibly” original to the car.

I realize that without knowing more, like gear ratios, especially 1st, it’s difficult to know how light a flywheel I can get away with for the street with a curb weight of about 2100 lbs., and a close-to-RS-spec 2.7l.

My hope is someone’s covered similar ground before, and can provide a point of reference.
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wndsrfr
post Jul 1 2020, 09:19 AM
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QUOTE(Rufus @ Jun 28 2020, 12:36 PM) *

Thanks for your input, stownsen914. About all that’s known is the case is a ‘73T 2.4l 7R, and the transaxle is a 901, “possibly” original to the car.

I realize that without knowing more, like gear ratios, especially 1st, it’s difficult to know how light a flywheel I can get away with for the street with a curb weight of about 2100 lbs., and a close-to-RS-spec 2.7l.

My hope is someone’s covered similar ground before, and can provide a point of reference.

I've got an AASCO aluminum FW on my 2.7RS+ engine... with the street clutch disk it's fine on the street. I'm near Va. Beach.... will pm you.
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wndsrfr
post Jul 1 2020, 09:44 AM
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My 2.7 had this fw on it when I got it from Josh
http://www.914world.com/bbs2/index.php?act...t&id=495546


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PlaysWithCars
post Aug 30 2020, 10:53 PM
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Running a lightened flywheel on the high compression 2.4E in my 70 914-6 and it works great. Love the quick throttle response and no problems street driving. You should be fine with your set up.
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Rufus
post Sep 4 2020, 09:37 PM
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QUOTE(PlaysWithCars @ Aug 30 2020, 09:53 PM) *

Running a lightened flywheel on the high compression 2.4E in my 70 914-6 and it works great. Love the quick throttle response and no problems street driving. You should be fine with your set up.


Thanks Mark (IMG:style_emoticons/default/biggrin.gif)
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