Hi
Thanks for the question.....
First of all...the Main girdle strengthen the whole bottom end.....It will eliminate cap walk....and keep the main "web" from cracking. If your using a "standard" cast block(non-high nickel) and plan on building a higher horsepower engine. Its a good investment in building and maintaining power.
If your using the high nickel blocks.....and plan on making lots of power....I think its very beneficial to use a main girdle for (if for nothing else) keeping bearing bores round.....
Secondly....if you have a 2 bolt block and want to make the bottom end as strong as possible with-out the expense of 4 bolt caps and the machining that goes with them......then the Girdle is much cheaper.
If you have any more questions please feel free to e-me at
bw61-1@bresnan.net