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Cal-look/High Performance => Pure racing => Topic started by: Jonny Grigg on October 05, 2010, 23:45:44 pm



Title: how thick is a motor plate?
Post by: Jonny Grigg on October 05, 2010, 23:45:44 pm
Another quick question....

My motor has a flange crank and I guess i'll need to spacer the motor from the trans a little bit. Ther car is a floorpan not a tube frame, so I presume I'll need to make a spacer in place of using a motor plate. I don't really want to modify the crank or flywheel at this stage, so I think my options are limited. How thick should the spacer be?

Thanks

 :)


Title: Re: how thick is a motor plate?
Post by: Neil Davies on October 06, 2010, 09:34:03 am
Jonny, when I had my flanged crank motor, we machined the heads of the flywheel bolts down slightly, and had to be very careful on clutch choice - the three puck disc had domed rivets so it would catch the bolts but the four pcuk had flatter rivets so cleared just about. IIRC we used around 2mm of washers on each of the engine to gearbox bolts too.


Title: Re: how thick is a motor plate?
Post by: Jay Aldred on October 06, 2010, 10:41:18 am
Jonny T6 motor plate is 6mm thick.


Title: Re: how thick is a motor plate?
Post by: lee-maynard on October 06, 2010, 13:33:59 pm
and don't forget ya starter motor


Title: Re: how thick is a motor plate?
Post by: StrokerMcDell on October 07, 2010, 01:01:14 am
I had major input shaft alignment problems with a 6mm sandwiched motorplate in a tube frame chassis.
Although it was CAD drawn and laser cut precisely from the CAD file and the 4 bolts holding the engine to the transmission lined up exactly (and i even welded in steel transmission mounts on the motorplate) I couldnt keep the input shaft off-alignment from pulling the input shaft seal open - resulting in a transmission oil leak on to the clutch. You can see the marks on the plate below where it was "fretting"
(http://im1.shutterfly.com/media/47b9cf27b3127ccef8d8f321c0a900000070O08QcNmjlq2Zg9vPh4/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/)
Fitting a 6mm sandwiched plate loses the inter-fit between engine and box

I eventually gave up and machined the motorplate to fit around the bellhousing
(http://im1.shutterfly.com/media/47a0dd10b3127ccef9ebb0802bf600000040O08QcNmjlq2Zg9vPh4/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/)
Problem solved.
Didnt have any problem with the starter when it was sandwiched but did have to fit a 5mm spacer between the input shaft / reverse coupler to move the shaft forward and fit a longer 7mm stud in the diff housing.

On reflection a 3mm motorplate would have worked better.



Title: Re: how thick is a motor plate?
Post by: Bernard Newbury on October 07, 2010, 19:19:20 pm
Be careful John. The first plate I had did not have the locating band letting the engine move wrecking the end main  Ring Martin Taylor as he made me a spacer plate with male/female locating around the bell housing as original. Perfect.  As Lee said you will have to modify your starter by machining the front plate and also extend the input shaft. I went through this grief a few years back when I got my first flange crank motor. The next flange crank motor did not need a plate. Bernie


Title: Re: how thick is a motor plate?
Post by: Peter on October 08, 2010, 13:32:33 pm
Hey guys,
Is such a plate always needed when using a flanged crank?

cheers, P


Title: Re: how thick is a motor plate?
Post by: StrokerMcDell on October 08, 2010, 15:24:58 pm
Hey guys,
Is such a plate always needed when using a flanged crank?

cheers, P

You know, I wasnt sure why the OP asked in connection with specifically a flanged crank either ?

I fitted mine to give a really solid engine / transmission mounting - also got the nosecone motorplated.
My engine is just an 8 dowel crank/flywheel with gland nut.

I think Neils reply regarding flange crank bolts relates to the need to have the tops machined off down to same level as the dimple in the centre of the bolt to prevent bolts fouling clutch plate.

David


Title: Re: how thick is a motor plate?
Post by: Jonny Grigg on October 10, 2010, 22:24:02 pm
Thanks for the replies. I am not sure what an 'OP' is though  ???. I may be in my mid thirties, but I am not an 'OAP' yet.  ;)

The reason why I asked was only as I was trying to think ahead. I don't have a motor plate, nor indeed do I need one, however I have a flanged crank on my engine and instinctively it looks like the flywheel projects further into the bell housing of the gearbox than a 'standard' 8 dowelled crank motor. I have not measured it, nor tried to put the engine in the car yet, like I say it is just instinct.....

I guess the only solution is to measure it off against a standard crank/flywheel arrangement and find out whether anything is in a different place to the stock location.

I take the pont about having a step in any spacer though to locate the motor and prevent any movement between the case and the trans.

Cheers  :)


Title: Re: how thick is a motor plate?
Post by: Deadly1 on October 11, 2010, 17:38:41 pm
Jonny
 Don't think there is any need to space out the bellhousing with a flange crankshaft. Everything ends up in the stock location on mine.
Some clutch choices end of too close but usually can be dealt with by clearancing the housing. Wayne


Title: Re: how thick is a motor plate?
Post by: StrokerMcDell on October 11, 2010, 19:09:47 pm
0P =original post