Main Cap Girdle?

I am building a 393 stroker with a windsor block. I just reecently got the block back from being bored out and cleaned up. The man that worked on my block talked about a main cap girdle. He told me a story about a 302 with a stroker kit that had split the block in half and said that if that 302 had a girdle on it that it might have saved it because it makes the block stiffer or tougher or something. I don't know too much about main girdles but it sounds like I should have one. I am not going to run a blower or NOS on my moter but I do want to atleast take care of it as much as I can. I made sure that my internals were properly balanced and that I got a forged crank, pistons, and the H-beam connecting rods and my engine bored out by people who actually took the time to blueprint the motor properly. That being said I would like to do what it takes to properly take care of my block and make sure that it lasts as long as I can make it. What I would like to know is how much would a girdle help my block and what are some things that I need to keep in mind when it comes to a main cap girdle? Any help or suggestions are very welcome, thanks.

Put ARP main studs in it and forget about the girdle. Most reputable and professional performance engine builders will tell you they are not worth there own weight. The block and main caps in the 351w without any trick parts will handle a great deal of horsepower.
ken

Indeed you have few worries. The late model 302/5.0 blocks are much weaker and are only rated by Ford for 450hp. If supercharged (lower necessary rpm's) they will go to over 600 before splitting. However, the 351W block is much stronger and, when properly built and tuned, will take over 600 NA/nitrous and over 800hp boosted. You're good.

David

I've been told by Keith Craft and his top engine builder (who are as good as it gets building Ford strokers!) that: "Those things are just to make you feel good, they don't really do anything but give you a nice big piece of debris to scrape up the rest of your parts with". I have had similar (although perhaps less colorful) comments from other highly respected builders as well.
I'm currently building a 550+ HP 408 and I'm using the ARP main cap bolt and not wasting any money on a "parts scraper".
Don

First of all, the way I understand it a stud girdle will not prevent an overpowered 302 block from splitting. They split in the webbing not from the main caps. I haven't heard of 351W's having this same problem especially the early, high-nickel blocks.
However just to offer a different view point, it just seems logical to me that tying all of the main caps together with a girdle will provide more strength and stability to the main caps and bearings. Its the same principle that applies to basic construction. Four walls are stronger and more stable once you install the roof beams. I installed a Canton set up in mine that is a windage tray/stud girdle combo, and a number of the engine builders I have spoken to still recommend a main girdle in high HP strokers.
Although, the thing you have to remember is that strengthening the mains will not prevent failures in other parts of the engine not related to the mains (such as the 302 webbing split). I think some people install one thinking that it makes everything bullet-proof.
Just my 2 cents.

Originally Posted by kgordonl

Although, the thing you have to remember is that strengthening the mains will not prevent failures in other parts of the engine not related to the mains (such as the 302 webbing split). I think some people install one thinking that it makes everything bullet-proof.

Just my 2 cents.

Correct, IMO.

The girdle is used to prevent cap walk and deflection.

I have seen both 351 Windsors and 400 engines with cap walk problems and a main Girdle would stop that . That is what they are intended for . There is not much chance of saving the block from splitting but the caps can't walk if tied together .

Originally Posted by MY TWO STANGS

I have seen both 351 Windsors and 400 engines with cap walk problems and a main Girdle would stop that . That is what they are intended for . There is not much chance of saving the block from splitting but the caps can't walk if tied together .

I'm curious as to your opinion about cap walk.
Do you (or anyone?) think that cap walk is a problem in an engine like the one I'm building, which is about 550HP at the crank and has a hyd. roller cam so it will very rarely see RPM above 5,500-6,000? I know it's a problem in high RPM race application but what about a 6,000-6,500 RPM street motor like mine?
Don

Hey Donraye, you won't have cap walk at that RPM. This is provided the caps fit in the registers correctly.

Originally Posted by benc

Hey Donraye, you won't have cap walk at that RPM. This is provided the caps fit in the registers correctly.

Thanks. I appreciate your reply. I thought that was the case but it helps to get other opinions.
D