Fit up problems for splines velvet drive
 

I'm trying to use a 6.2 LS3 with a Mercruiser Chevy inboard bell housing, Hardin flywheel #755-8649 and Hardin damper plate #220-96115 and a 1:1 Velvet Drive Transmission built by BAM. With all this assembled I'm only getting about 1/4 inch spline engagement. My mind says this is not right. Seems to me it should be more like one inch engagement or more. Any help solving this problem would be greatly appreciated. Thank You!!

It never makes an inch however 1/4 is not enough. Do you have a rear mount plate? Most likley you need to cut your bell housiing. Also we have a deep drive plate that adds a bit

https://www.mercruiserparts.com/dp10...ne-drive-plate

Attachment 577926

not sure what bellhousing you have but LS series engines use a different depth housing. i.e. you cannot put an LS T56 trans to an old school small or big chevy because the LS trans has a longer input shaft and vice versa. you have to buy a scatter shield that compensates for it.

Thanks Marc! I'm not sure what a rear mount plate is? I'm bolted engine block to bell housing. My block is supported by front side mounts and mounts on the velvet drive trans. What amount of engagement do you recommend? Took my brain a bit but I'm not using a rear or front mounting plate.

Thanks Compedgemarine! I don't have a part number for the bell housing. bought of EBAY. I wonder if I'd be better off just buying the Harden bell housing?

https://cimg7.ibsrv.net/gimg/www.off...f376c9998b.jpg

SBC and BBC have a crankshaft flange surface that protrudes 0.400" from the block bellhousing mating surface.

LS engines have a flush (0.000") crank flange protrusion. 1999-20 LS 4.8/6.0 engines do have the 0.400" protrusions.

I think there are flywheels made to move the flywheel surface rearward the required amount.

https://www.hitechclassics.com/produ...g-m-muscle-car

Likely cheaper options.

Probably cheaper to buy a flywheel with an extension, vs a specialized scattershield. Then you can source/use all the Merc bellhousings.

I learn something new every day. With zero LS experience this is good stuff for me to know.

Would this help? I have one on the shelf im not using.
https://cimg4.ibsrv.net/gimg/www.off...7aa21f9391.jpg