We carry both used original replacment type main caps, and aftermarket upgraded billet types. "RB" (413/426/440) engines use different caps then "B" (361/383/400) engines, since the main bearing size is different. Used stock replacement caps are also available individually or in sets (while supplies last). Don't throw away that block just because the caps were lost years ago.
Our new billet steel main caps finally allow you to upgrade the strength of your block for an incredibly reasonable cost! With the increased popularity of our stoker kits and forged rotating components, the block and factory cast iron main caps are often finding themselves as the weakest link in modern stroker engines making over 600-650 horsepower. With these upgraded caps, you can extend the reliability of your factory block far beyond that range... and for a small fraction of the cost of other main caps on the market, or especially an aftermarket block. These caps are FACTORY HEIGHT. That means they are compatible with any off-the-shelf Big Block Mopar main studs or bolts (no special lengths required) and they'll work with any of the aftermarket girdles available (for a super strong combination) AND you won't have interference issues with the aluminum rear seal cap due to these caps being taller than stock. The bolt holes are spot faced to make sure the main stud nuts and washers have a flat, even surface to clamp down onto, and the thrust surface is already pre-cut into the #3 cap. We've thought of everything. And, the best part? We include ALL FIVE caps for the incredible price listed. A great choice for upgrading an old set of cast iron factory caps, or even for replacing a set of missing originals. These work with both "B" and "RB" engines. As with any aftermarket main caps, fitting the caps to your block's registers and line boring and/or honing is required.
Our new 5 piece billet steel CROSSBOLTED main cap set finally allow you to upgrade the strength of your block for an incredibly reasonable cost! Similar to the factory HEMI crossbolted setup, this allows you to convert your standard wedge 383/400/440 block to a super strong crossbolted setup. With the increased popularity of our stoker kits and forged rotating components, the block and factory cast iron main caps are often finding themselves as the weakest link in modern stroker engines making over 600-650 horsepower. With these upgraded caps, you can extend the reliability of your factory block far beyond that range... and for a small fraction of the cost of other main caps on the market, or especially an aftermarket block. These caps are FACTORY HEIGHT. That means they are compatible with any off-the-shelf Big Block Mopar main studs or bolts (no special lengths required) and they'll work with any of the aftermarket girdles available (for a super strong combination) AND you won't have interference issues with the aluminum rear seal cap due to these caps being taller than stock. The bolt holes are spot faced to make sure the main stud nuts and washers have a flat, even surface to clamp down onto, and the thrust surface is already pre-cut into the #3 cap. We've thought of everything. And, the best part? We include ALL FIVE caps for the incredible price listed. A great choice for upgrading an old set of cast iron factory caps, or even for replacing a set of missing originals. These work with both "B" and "RB" engines. As with any aftermarket main caps, fitting the caps to your block's registers and line boring and/or honing is required, as well as milling out the trusses of the block for the "ears" of the center three crossbolted caps. This setup, along with a main girdle kit, is about the strongest, most bulletproof thing you can do to a factory block. Click on the "view additonal images" button to see a side view of the center crossbolted cap.
Our new 7075 T6 Billet Aluminum main caps finally allow you to upgrade the strength of your block for an incredibly reasonable cost! Our 7075 aluminum is just as strong as the 7075 aluminum used in the "name brand" caps costing over twice as much!
Our new 3 piece billet steel CROSSBOLTED main cap set finally allow you to upgrade the strength of your block for an incredibly reasonable cost! This kit includes the three center crossbolted caps, which are the ones which hold most of the load of the engine. Similar to the factory HEMI crossbolted setup, this allows you to convert your standard wedge 383/400/440 block to a super strong crossbolted setup. With the increased popularity of our stoker kits and forged rotating components, the block and factory cast iron main caps are often finding themselves as the weakest link in modern stroker engines making over 600-650 horsepower. With these upgraded caps, you can extend the reliability of your factory block far beyond that range... and for a small fraction of the cost of other main caps on the market, or especially an aftermarket block. These caps are FACTORY HEIGHT. That means they are compatible with any off-the-shelf Big Block Mopar main studs or bolts (no special lengths required) and they'll work with any of the aftermarket girdles available (for a super strong combination.) The bolt holes are spot faced to make sure the main stud nuts and washers have a flat, even surface to clamp down onto, and the thrust surface is already pre-cut into the #3 cap. We've thought of everything. These work with both "B" and "RB" engines. As with any aftermarket main caps, fitting the caps to your block's registers and line boring and/or honing is required, as well as milling out the trusses of the block for the "ears" of the center three crossbolted caps. This setup, along with a main girdle kit, is about the strongest, most bulletproof thing you can do to a factory block. Click on the "view additonal images" button to see a side view of the center crossbolted cap. Actual exact shape of the caps may vary slightly from the picture, depending on stock.
When bolts just aren't strong enough, you have to go to main studs. Our ARP main cap stud kit are the strongest main studs you can buy for the big block Mopar engine.
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440 Source Inc.
3680 Research Way Carson City, NV 89706
775.883.2590 / Sales@440source.com
