So just doing some polling, how much HP did you get by with on a 440 with stock main caps and a girdle? Thinking 550HP to 600HP might live?

I don't think there's any cast-in-stone numbers on that. Just opinions. Maybe general consensus is a stock block will live at 600HP. (But my friend's didn't.) Another friend just put together a 600HP with a girdle. Hopefully it will stay together longer.

And what this conversation really brings up is that there really isn't any reason to think about more power these days. Trick this and secret that and all that silly stuff. Just take a stock B/RB block, put in a stroker kit and a Trick Flow top end and you're done. You have 600HP and all the power you will ever want on a stock block. Much easier than the old days when you had to plan on your engine build for a year. This isn't the 70's. We have some great parts to work with now-a-days. Trick Flow heads flow as much (or more) than stock Street Hemi heads. No wonder they make so much power.

I ran aluminum main caps and still had the block crack. It was filled with concrete about half way up and and cracked between freeze plugs. The block itself never failed. Personally if you have a light rotating assembly that you don’t spin too hard it may live. I just saved my money and bought an aluminum block. I would not build another cast iron block again, to me it’s not worth it. My 2$. i never had my cast iron junk on the dyno, but with cast iron heads in my dart it ran 9.70 all day long. It ran out of steam about 6700 rpm, no more air left.

Why would you want to use a girdle on a BB Mopar V8, they do nothing to strengthen the blocks
Look at the main webbing in those blocks, B and RB as well as 426 Hemi, the 426 hemi block is the only block that benefits with the side main cap bolts due to the extra iron cast in their main webbing from the factory.
I will say this, I've built a bunch of 600+ HP pump gas street and strip 440 with stock caps and aftermarket bolts as well as new main studs, neither one will add strength to the main webbing.
Your best bet for changing parts on the 440 blocks to help them live is to add a set of good quality aluminum main caps and studs, forget the girdles
BTW, the stock 400 blocks are way thicker in the main webbing than any of the production 440 blocks, car, motor homes, trucks and marine blocks.
Make sure and have then sonic tested by a good shop before starting as the cylinder walls can be thin
If you want to make a lot of power, above 750+, start with a good after market block

My post was to gain some experience from the group. I have been building 440's for many years and yes the aftermarket block is definitely the way to go. I sold my race car this spring, which had an aftermarket aluminum block which I was very pleased with. I am 67 and decided to build one more fun race car from all the collected parts in the shop, and not burden my family with trying to sell or get rid of them. A functioning car is a much better way to sell them off when needed. I have a fresh 440 block bored and ready to assemble that I have had for 10 years in a plastic sack. From my experience number 2 main cap is the most likely to break, and I have had the concrete blocks crack on the outside, usually if you measure the cylinder walls they are barrel shaped, so the pressure transmitted through the concrete is what cracked the blocks. Got one coming in with just that condition. But I have a 34 Ford fiberglass body which has been sitting for 15 years, and I decided to make it a race car instead of a street rod, Going to use a Mopar drive train and a 34 dodge grill shell, and just call it a 34 Dodge. should come in at 2,500 lbs so 550 HP will get it into the tens, which is all I want to do. Don't want the hassle of certified chassis, NHRA drivers license, heavy hot fire suit, etc. Just want to go to the track and make some fun runs, and maybe bracket race a little, and hit a few nostalgia drags. So I don't want to drop a lot of dollars, I want to use up what I have, bang for the buck.
I will post a picture if anybody wants to see the progress.

First, they cause no harm that I can see, and "strengthen" is rather subjective in this context. But I would find it hard to imagine someone can make the case that a girdle in this application does not at the least help dampen any harmonics of the caps in mostly 2d.
Now whether that is important or useful is another discussion.

At that power level just use ARP main studs. Girdles are a big hassle. They get in the way of the oil pickup, the windage tray and the oil pan. Major hassle for a street car and not needed at your power level.

With all of the tricks, if you get up to 700hp, it will crack is short order.600HP? Don't let it detonate.

Hughes claims over 900 plus hp and no failures with there girdle......

275 passes running 8.60’s@155mph in my Daytona at 2500 pounds before I found a crack in my block. Never leaked a drop of water. No concrete no griddle. Like it says above over a certain point they all crack. I actually thought 275 passes was pretty good as it would take some guys a long time to put on that many.

Definitely post pictures! Sounds fun

Put One on it., It will probably last as long as you need it to. https://board.moparts.org/ubbthread.../422390/filename/Girdle%20on%20block.jpg

I've built a couple 9 second 440's one went several years before cracking, and the other is still going after 7-8 years with no cracks and probably 50 -75 runs a year the one that cracked had aftermarket steel caps, the one that's still going has all stock stuff with studs, with number 3's hole opened .050. No girdle.

900??? Bologna. Claims is the operative word.

550-600 hp I wouldn't bother w/ a girdle.
I had a .030" over 440 that made around 625 hp w/ just ARP main bolts and stock caps and it was fine. Caps were walking of course, but no problems. Put a lot of runs on that motor.
That motor later got freshened up w/ some upgrades that put it at the 700 hp level, but I ended up selling it before I ever put it down the track.

I always say call the source and complain to there complaint department.



900??? Bologna. Claims is the operative word.

http://www.hughesengines.com/TechArticles/2mainbearingstudgirdles04232007.php

I don't think adding a girdle hurts, but I'm not sure if it actually helps. Maybe there is a benefit from tying together the stock main caps to reduce the "flagpole waiving" effect, if that is one of the things that contributes to the stock caps cracking.

Switching the center 3 caps to billet 4-bolt main pieces on a stock 440 block didn't stop the new caps from walking at 600 HP. I'll be interested to see how long it holds up with 650+ HP.

My backup block has been machined for the old style aluminum main caps and I bought a girdle for it, too. It'll be more of a PITA to build the bottom end with it, but in my twisted perspective it still makes sense.

Here is a couple pictures. Got the cage done, next step is build a set of headers and get them shipped off to be coated, and then hang the doors.

A very good friend, Tom Hemphill made girdles before girdles were a thing. When we all stepped up into an area where we were hurting blocks nothing worked. His customers cracked blocks regularly. We were fine into the 9’s but we soon found their limits and aluminum blocks were ordered and put to use. It was crazy to put money into a stock block if you wanted to go fast.

great looking project JW !