Aluminum main caps or Billet with a girdle?

Just what it says. For the new 499" low deck. Which do you prefer? Half fill also maybe?

Race only,1/2 fill,studs and aluminum caps.

I'd do aluminum caps and studs. Nothing else.

I am on record as thinking the girdles are a waste. With a stock block, I have had good success with a fill, aluminum caps, alum rods and good studs. Just don't think the girdle in any way addresses the problem with these blocks. Others disagree and that's fine.

Many will say they have a girdle, X amount of power and no broken blocks. That is likely true. I can also say I have run 1000hp stock blocks with just the caps. Now how long would that block HAVE lasted if run for a long time......I have no idea, just like they have no idea how long it will last with a girdle. Stock block is a crap shoot at best, regardless of how you prepare it at a big HP level.

I agree with using the after market main caps and studs, no girdle But I don't use block fill either though

1/2 fill and studs is all I ever do.

Is the short fill an issue for cooling as street car?

After a ton of reading, I went with Aluminum caps and studs. Everything looked perfect when I did the winter refresher, the mud truck probably spends more time at WOT then most bracket cars but its hard to compare.

Curious on other peoples thoughts though, I was reading some LS stuff today. Would pinning the cap, or a dowel type sleeve on the bolt like a rod help anything? would it even be possible? less room on the cap surface I think. seems popular with the ls guys.

What did the side of the aluminum main caps and the block main cap register look like?How is the mating surfaces between the main caps and block? Is it walking or transferring metal, fretting? BTW, it ain't a Chevy

They argue about girdles, so the world isn't that different over there!

I run a girdle and steel caps with a short fill, engine has been together and raced 10 years, been freshened twice, all has looked ok, I went that route since it just didn't seem to be a good idea to have the aluminum caps with the old stock cast iron block. If I was rebuilding Id go the other way though I think. Ive seen enough of the stock block aluminum caps hold up that even though it didn't sound good to me back about 12 years ago when I started building that engine I'd go that route now, I would do a short fill though either way.

Eric, my new 512 will have aluminum cap's,studs and girdle, all BCR stuff, my machinist advised me against any fill in the block.

our stuff is all USA made with USA materials, we've had a lot of success with the girdles and I tell people its just and insurance thing. some people don't think they need them others like having them. only you and your engine builder can make the call.

I think it is. I had a 500" low deck in my 9 second 69 Dart, after 15 minutes of street cruising my oil would get hot and would idle at 18-20 pounds at a stop light, always made me nervous. Now I have a 500" low deck in my Duster with no filler and it doesn't cook the oil.

I think a good oil cooler setup would help tremendously though.

On my 505 stroker pump gas engine I used the BCR girdle ,aluminum main caps, ARP studs. Block is 1/2 filled. After 8 years of running close to 1,000 1/4 mile hits the block wasn't cracked, no cap walk . If it last another 8 years I'll be to old to get in the car, well maybe out of it.

Sounds like a good setup.

Personally, I don't think a short, or even medium fill hurts cooling. These motors circulate little water at the bottom of the cylinders anyway. All the heat is at the top of the bore

What happened to the piece that BG built you if you don't mind me asking?

I let someone else try to fix it when the block sprung a leak. Downhill from there. Bob built a nice piece.👍

For what its worth i have a 484ci(low deck)It ran 8.90's in a 3500lb car the block is half filled(never gets hot)and has the Aluminum main caps....No matter how hard i try...missing gears i can't kill that motor....going on 15 years now

I've been running a half fill on the 440 in my Roadrunner for 15 years. No issues to date.

Spoke with Mike Janis yesterday and dropped off the block. I have main studs already and I'm going with an aluminum cap. Not sure on the fill yet. Going to try to make this one last so any cam change will be just to use the same grind if this one is damaged.

I have lots of experience running aluminum main caps on stock BB Mopars. I like them if you want to run steel rods. If you are willing to run aluminum rods, then ductile or steel main caps are the way I would go.

I would still inspect aluminum caps for cracks at every rebuild/freshen-up. A very close look can catch a crack before it goes all the way through. And I even found cast iron caps cracked in half at an inspection before the block let go. Set an inspection interval (maybe 2 years or 500 passes?)