BB girdle with stock caps good as cross-bolted conv?

I will say this. Don't cross bolt unless you have a vertical mill. I have lost track of the hours that I have spent so far.

Wholly shoemaker. Adding extra bolts on a stock Mopar small block or big block is like putting a band-aid on a person that had their leg cut off.

you need alot more tooling than a vertical mill to install cross bolts in a block. the girdles are basically a bolt on with minor machining that any competent shop can do. or you can do at home if you have a vertical mill. won't require you to tilt the head even.

FWIW, my 452's block has the Pro-Gram cross-bolted #2-4 caps. The shop that did the install recommended them because of indications of cap walk during a previous rebuild "way back when". Guess what? Even the Pro-Gram caps show signs of cap walk after being run at 600 HP, too.

Also, my installation has them going in as a press-fit, rather than having any side clearance where the block gets drawn in when tightened down. And those caps are a total PITA to remove as a result because they didn't have an provision for attaching a slide hammer to draw them back up.

My backup 451 block was machined w/ the old plate-style aluminum main caps back before I knew about the improved BCR and Best Machine versions. Since I know the plate-style design isn't ideal, I'm going to run a CRE girdle kit w/ 'em to help keep things strapped down.

And if/when time comes that I need to put my last core 440 block into service, I'll either pop for some BCR caps or just run a girdle w/ the OEM caps, depending on how I see things turning out w/ the 451.

I guess what I'm saying is I vote "No" on the Pro-Gram cross-bolted conversion deal and would try a girdle w/ the OEM caps, instead.

don't waste time with oem caps. the main benefirt of caps designed to work with a girdle is that they contact at their center just below the crank. when all is said and done, your stack up should be crank, bearing, main cap, girdle, not crank, bearing, main cap, air gap, girdle. i will post some pics today of what i'm talking about. also our girdles are 1/2" thick plate steel. alot of the other on the market are thinner and not as strong.

I went with stock caps and a 440source girdle for my 500" low deck.

The best possible setup is the girdle with aluminum caps, and having the caps milled to not require any shims or spacers for proper assembly. Spacers make it a Pain to assemble.
If you don't have a crankshaft yet, a center weighted crank puts the loads more where they belong, across all the bearing caps, not most of it on 2 and 4. My Mega Block had cap walk issues till I bought a center weighted crank.

Well said, Jerry! All the points you made are valid.
My hat is off to anyone trying to make a living selling USA-made parts to the Mopar crowd.

R.

here is some education for those considering any of these reinforcement options... the cap in the pic below is made from 7075 aluminum and is a cross bolted main cap for a hemi. as you can see the crack that formed is all the same location where most of the big block cap failures occur. the crack starts are a radial line shooting outward from the crank bearing journal and ending at the high stressed area where the main stud nut would be located. cast caps fail this way as do stock replacement style caps when the power levels go up. (i can't pin point an HP level because not everyone puts their cars on a dyno or runs at the track.) this cap below also shows tons of evidence of cap walk on the block mating surface.

here is a pic of our girdle caps getting fitted into a 440 block, obviously the block still needs to be cleaned up and this was just mocked up for the picture. in the #3 main you can see the cast block reinforcement buttress. this cast rib is what allows the stress from the main bearing saddle to be distributed to the skirt of the block. our girdle cap mimics this angle and fits along side it without needing any additional machining or grinding. this serves 2 purposes, first it distributes the load seen by the cap into the girdle and across the entire base of the girdle. and two it creates a pocket where the crank rotates and helps to minimize windage losses.

these buttresses are what needs to be machined away in order to install cross bolted main caps on a 440. someone recently asked my how i would install the cross bolted caps and the answer is i wouldn't but if you fitting them there are two critical areas that need to be fit properly. first is the side to side clearance on the block. this needs to be kept to minimum and an interference fit would be better so the block skirt isn't being pulled in adding stress. the second area is that on the buttress you need to machine a flat, so the area relieved looks like an L in the corner of the L you want there to be a radius. as seen in the pick above there is a radius at the bottom area of where the crossbolt would screw in. ideally the cross bolt cap should touch both parts of the legs of the l shape this will help transfer the load away from the crank centerline. (sorry this is really hard to explain and fairly difficult to machine as well).

i am getting ready to do an install video for bcr caps to post up on youtube and i'll throw in some theory and chalk board time for those really interested. if your not you can fast forward through it.

last post i promise. below is the pic of the clearance area between a stock cap and behind it you can see our girdle cap. our girdle caps make contact over the entire length of the girdle not just at two points where the studs are located. also we incorporate the #5 and the #1 cap into the girdle as well.

some guys are even running windage trays and crank scrapers with our girdle and i'll cover that in the install video.

Beautiful product, made with some Swedish help i think.

Yes and how is our Swedish friend have not heard from him in a long time. Those design phase days were fun times and and without the Swedish engineering it likely would still be a drawing. When all was said and done we made no improvements to what you see Jerry doing today. Hats off to all that were involved from Dan Vern Jim etc and of course Jerry for keeping this thing alive.

Greg

Just wanted to announce the new pricing for the girdle kits

girdle kits $625.00

girdle caps $350.00

i put all the details in the hot deals section and we are still honoring the moparts 10% off until the end of the sale.

yes the girdle kits include the main caps, arp studs, and oil pan rail studs and nuts as well as the main cap to girdle studs and nuts

Thats too cheap!!

Yes that is cheaper than when I was building them Jerry has done a great job taking this product to the next level. He has ramped up production and is getting this product out more than $100 cheaper than i did ten years ago!!
Way to go Jerry the Mopar crowd is very pleased!!

Greg

hopefully by this time next week the ebay store will be up and running as well to streamline ordering for everyone. so anyone who doesn't have a tech question can just point click and buy.