Girdles are for Fat Ladies

Dave Simpkins

New Member
Joined
Mar 17, 2002
Has anyone tried making a S1 bottom end more like a S2 ?

That is to say, milling the S1 block to accept 4 bolt main caps at#2 and#3mains (just like a S2). The obstacles that I see here are the oil pick-up hole in the block at the #2 main and the dipstick hole into the side of the block at the #3 main.

Im thinking the oil pick up can be overcome by doing a regular cut into the block/web at #2 for the 4 bolt design cap and then milling the cap for a sleeve that would pass through a "corner" of the cap and then break out into the original pick up passage. The sleeve would be welded or staked to secure it. I think this way the #2 cap could be removed without disturbing the oil pick up, and the oil pick up would remain pretty much original. An alternative to this would be to cut into the bulge on the inside wll of the block, that is the uptake oil passage going to the front of the block (oil pump intake). A tube fabricated with the flat pad and 2 fastener holes identical the the stock pick up at the #2 /pan rail could be threaded and secured into the passage ahead of the original location, sort of half way between the stock location and the back of the #1 cap. Ummm. not sure about clearning the rods ??

The dipstick hole could be welded or tapped and bolted shut, then the milling of the #3 web would go on as normal for the 4 bolt cap at that location.

A modified oil pan (a 2 piece tube welded into the side of the pan) and a lengthened dip and modified header bolt mounting bracket should work there. The sleeved together 2 piece tube would make for esay removal of the pan, as the short end of the tube would remain on the pan and the longer end would come off as the stock dip tube does.

Then ... just like doing the girdle deal ... ARP studs, and line bore if needed and line hone for sure. This would stiffen up the bottom end of the S1 for less weight than a girdle and 'bout the same or less mill time. Caps from Pro-gram Eng. are the only ones I've heard of... are there any other manufacturers making 4 bolt steel caps for the wheezer blocks?

Anybody tried this or some variation of it. I figured girdles are for fat ladies.
 
Well,

The S1 and S2 blocks are made from the identical raw casting. The S1 block is machined just like the production engine (all the passages are in the same place).

The S2 block received a revised machining. In the specific area you are talking about, the oil pump pickup at #2 main is machined away for the bigger main cap and the boss at #1 main is machined for the new location.

If you can find 4 bolt center caps and someone competent to perform the milling work needed, you could simply machine the boss at #1 main on a S1 block.

I have a S1 block (and a set of caps) and I was headed down that path a few years ago. After looking for someone who would take on the machine work task, I decided (with the advice of Ohio George) to install 2 bolt billet main caps at all 4 positions and leave the oil system alone.

The real strength in a stage block comes from the extremely beefy main webs. Put a stage block side by side to a 109 block and you will understand what I am saying. Is a S1 block with billet caps as strong as a S2 block? No (I think that is obvious)
But I'll bet a S1 block with billet caps is more stable than a girdled 109 block and a S1 block can be drilled to accept 14 bolt heads.

Dave
 
You can use the stock dipstick location with the 4 bolt caps installed. I have this on my S2 motor, it is close to hitting the cap but doesn't.

I would press in a plug and use the S2 wet sump type pickup at the #1 main location. I would try to get 2 bolts to hold that flange in place and use a mounting bracket and use a windage tray stud on the #3 main to hold the lower section of the pickup in place, or just go witht the Duttweiler oil pump and a external pickup and feed through on of the oil galley bosses, but you will have to drill and tap that on your S1 block.

I guess since you will be starting from scratch on your pickup, maybe just drill and tap a thread on the pickup and eliminate the 0-ring deal like what is used on most internal pickup S2 motors maybe?
 
With splayed 4 bolt caps on my Stage1 there was no way to put a dipstick in the factory location, and with a 3.625 crank i had to clearance the block thru the dfactory oil passage,and didnt see any way around it, So i just bought a Pan and a aDuttweiler oil pump.
 
4boltcaps

Im meeting with the machinist before Friday, to scope out the block. I think with a little trick close tolerance milling, I can keep the stock oil p/u at the #2 on the pan rail .. just by cutting a small radiius on the corresponding edge of the splayed 4 bolt cap. Will know for sure shortly. I'd like this to work cause it saves $$s on a new oil p/u system if I can keep it stock located.

Anybody got dimensions or better yet "shop drawings" for the Pro-gram splayed 4 bolt caps ??
 
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