Here’s a past thread on the main support girdles.

http://forums.y-blocksforever.com/Topic62451-5-3.aspx#bm62646

Lorena, Texas (South of Waco)

Paul.  This engine requires much higher octane fuel than you can get at the corner store.  In this case, Sonoco 110 was used.

Lorena, Texas (South of Waco)

Ted: Since we're on the subject of the outstanding results you achieved recently with a customers 375 cu. in. engine. Who would have thought, say 4 years ago or so, that a Ford Y-Block could hit over 580 H.P & over 500 lb.ft. of torque, on a 4 Bbl intake!? I found your preamble in the article about exhaust temperature & oxygen sensor readings interesting.. I have to admit that going back to your 2010 EMC entry, it crossed my mind that maybe a 375" engine was maybe a bit to big to get an optimal score. Mind you, I have virtually O qualifications to make that kind of accessment.. Anyway, I have one question, what kind of fuel is needed for the 13.5 to one compression ratio?

Paul

Barry.  As a general rule, main support girdles need to be the same material as the block so that expansion rates are the same.  I’ve some horror stories here where aluminum girdles are used on iron blocks.

 

For the Y, the main support girdle is made from 3/8” thick steel.  Any thicker than this and they get pretty heavy.  The studs I either make or get through Granger or MSC simply due to ARP pricing being out of sight and still having to modify the ARP studs for the final fit.  By lining up all the main caps in the mill vise together, all the caps are machined to the same height at the locating washer spots or bolt holes.  All this after the mains have been align honed.  Only the area around the main cap bolt holes is machined.  There are equal thickness washers between the girdle and the main caps and this thickness is taken into account when machining the main caps.  The main caps are machined so the girdle sits ~0.006”-0.010” above the pan rail when the girdle is torqued to the main caps.  The girdle is then pulled down to the pan rail when the outer 5/16” girdle nuts are pulled down.  A thin film of RTV goes between the girdle and the pan rail.  The oil pan gasket is still used between the girdle and the pan.

 

If you’ll email me directly, I’ll send you the girdle instruction sheet.  Contact info is at  www.eatonbalancing.com .

Lorena, Texas (South of Waco)

Thanks Ted for the article "585 horsepower" in the new Y-block magazine.  A few ( a bunch, really) questions on the main girdle ; how thick, steel or alum.? Are the studs ARP's and what application? Is there a gasket between the girdle and the block or just thin sealant? Are there spacers between the main cap nut and the underside of the girdle?   Barry L.