i've heard some engine builders say they prefer nodular iron caps over billet steel because the iron caps have more similar characteristics to the factory iron engine block.therefore,expansion and contraction from hot and cold cycling doesn't differ from the block like the billet caps.i want the best choice for my street/strip engine,what should i go with? thanks again.

Street/strip to me will be fine set up like stock!! Probably way overkill for your application unless you are going to Nitros Gas h-ll outta her sometime in the future...

And if you want a little added insurance just install a main stud kit. Be it two or four studs..

Now a full-house drag motor or high speed, hard charging, road race motor can use splayed main caps if it is REALLY high hp AND HAMMERED ON!!!

I installed a two bolt main stud kit in my mild 496 BB b/c I wanted a little more peace of mind...

I spun my crank and set the thrust bearing as usual as I torqued my mains down in stages and my motor didn't require line honing b/c it spun fine!! Some blocks might require line honing tho??

Imho..

pdq67

i'm planning on a 200 horse nitrous hit on top of my projected 575h.p./510tq.,14:1 compression stroker smallblock. tongue.gif

Originally posted by bowtie455:
i'm planning on a 200 horse nitrous hit on top of my projected 575h.p./510tq.,14:1 compression stroker smallblock. tongue.gif On a small block with that much power and compression I would go to the flat bottom splayed center caps from Pro-gram engineering, We install caps for engine builders and shops all over the country and most of the time we end up putting a front billet cap and strap the rear main cap or install a billet rear main and so far have had good luck with these caps with this much power.

I agree with Carl completly.
If you are going to the expense of putting splayed caps on the block use the billet.
The "old wives tale" about the difference in material is bull.
All the aluminum block use billet & I think the expansion rate between aluminum & billet is a bit more than cast & billet :D
Only thing we do on the aluminum blocks is tighten the clearance up on the mains a bit.
The Oliver or ProGram caps are the ones we use.
With that said, unless you are limited by rules get a Bowtie or Dart block.
They are way thicker, the lifter bores are where they belong, blind head bolt holes, thick deck, priorty main oiling,,, the list goes on.
By the time you do a stock block right for a 700+HP deal you will have put a huge dent in the price of a Dart ;)

You can also order it with a raised deck & cam & wide pan rails for about the same price.

thanks fellas! smile.gif