Bolt size for Chevy bell housing

[teamHOLDENracing]

Hi guys

Can anyone tell me the thread size for the standard Chevy LS2, 6, 7 bell housing? I think it is M10 x 1.5 x 40 mm which is not the standard M10 thread pitch

ETA: Sorry - I mean the thread spec for the gearbox mounting holes on the bell housing

Many thanks

Andy

Edited by teamHOLDENracing on Monday 25th February 10:48

[Boosted LS1]

Not sure of the size but I've probably got some in stock as well as a gearbox so I'll check later.

Boosted.

[teamHOLDENracing]

Thanks Mike. I have a Tilton bellhousing with the standard Chevy 4 bolt pattern and an adaptor plate made up to take a Holinger box. Only I don't seem to have a single bolt to fit!

[teamHOLDENracing]

Its 1/2" UNC, just in case anyone else ever need to know

[stevieturbo]

teamHOLDENracing said:

Its 1/2" UNC, just in case anyone else ever need to know

LS1, LS2, LS6, LS7 etc etc and T56 all use metric fasteners. M10x1.5mm is standard fit, for bellhousing to engine.
It is also standard fit, T56 to Bellhousing.

The older SBC engines, and non T56 transmissions may well use imperial threads though.

[teamHOLDENracing]

Steve - agreed, bellhousing to engine is standard M10. But the gearbox to bellhousing bolts are not when using an aftermarket Tilton ultra low ground clearance magnesium bellhousing...

Cheers

Andy