using EA81 flywheel with 5 speed DR EA82 tranny swap

[yamahammer]

Hi there,

First of all thank you all who have performed 5 speed swaps into your EA81s and shared your troubles and triumphs along the way.   I would never tackle this project if it weren't for people like you posting so much info and detail that makes it simple for people like me to have everything lined up to make the swap as easy as it possibly can be.

I am stumped on one last thing after getting almost everything I need together to convert my 85 auto Brat to a 5-speed DR and hope you all can school me on this.  BTW, I will be using Jerry's kit to simplify the job.

My question is this:
I would like run an EA81 flywheel with a complete EA82 clutch kit.  I understand I need to reduce the step to .825" from the current ~.9 step.  When this ~.1 is removed (accounting for some removal to clean up the friction disc surface) from the rear surface of the flywheel (as it sits in the car) it appears this would also remove ~.1 from the width of the starter ring gear since it is flush with the rear surface of the flywheel.  Is this reduction in ring gear width okay or must I remove the ring gear before machining and replace it afterwards?  I was about to set out for the machine shop when I noticed this and cannot find any info specifically regarding this.

 

Maybe this flywheel has already been machined and when it started life the ring gear was pressed-on beyond the rear surface?

If someone could set me straight on this I would be most grateful.
 

Thank you

[Gloyale]

A good machinist will pop the Ring gear off the flywheel first.

 

Step IIRC should be .815

 

 

Biggest issue some have had with using the EA81 flywheel, is that it's thicker overall.  Sits further into the bell of the EA82 5spd.  Might need to space the starter out with a few washers.

[LeoneTurbo]

Why not use the EA82 flywheel with the EA81 engine?

[yamahammer]

Gloyale,

Thank you for your response.  I will have the ring gear removed before the flywheel is resurfaced and hope that there is enough surface left under the ring gear to retain it when it is pressed back on.  I am thinking the outer 1/3 of the ring gear will no longer be supported after machining.  Does this sound okay?  If I have to I could weld the ring gear to the flywheel to make sure it cannot work its way off, and try not to get it hot enough during welding to affect the heat treat of the teeth.

 

I originally saw .815 step and then .825 step but if you say .815 then I will use that figure for the step, and plan on placing a washer or two under the starter ears.

 

 

 

LeoneTurbo,

Thank you for the alternative.  I prefer to use the EA81 flywheel because of the smaller bolt holes but I am certainly not ruling out use of the EA82 flywheel if I need to.