I have a 1970 440 HP block thats been siting here for a long time and am ready to build it. Bare standard block.

I have a CPPA forged steel crank & standard harmonic balancer and a set of factory non-6-pack rods.

If I was to was to use the L2355 six-pack pistons to keep it close to stock, would not having the heavier 6-pack rods be an issue. The L2366 piston is too low in the bores. My other option is a 440 source piston or KB, etc.

I plan on running in Pure Stock, so I have stick within the rules.

Thanks
Chris

not an issue & the std rods would be lighter but with this being a FT dragger I would consider some aftermarket rods/lighter pistons (if the rules allow)

If the rules allow for using a lighter piston do so, and lighter stronger rods, too.

My race 440 was built as a "super stock" motor quite a while ago and stretches the rules for stock as much as possible. It uses L2355 .030 pistons and LY rods on a offset ground steel crank (balanced, of course)but if I were to build it today, I would be using lighter forged pistons, newer H rods and a 440 source stroker crank because mine is a bracket racer.

If rules allow, get lighter pistons with the thinner ring pack.

Look for pistons with a compression distance over about 2.060" to get the higher compression pistons (2.060-2.067")

The Speed Pro L2355 may be the least expensive, but also the heaviest and use the standard 5/64" rings.

The SRP, Probe, and Ross shelf pistons are not that expensive, are lighter and use the 1/16" rings.

I think all the 440 Source pistons use the smaller 0.990" piston pin.
If you are allowed to use aftermarket rods with the smaller 0.990" pin, then there is a several pistons for that too.

Which "Pure Stock"

From what other members here have reported, the 6-pack rods are just as weak as the LY rods in the rod cap/bolt area, and run the same size rod bolt. This is the weak spot on the factory big block rods and the consensus seems to be 6-pack rods are a waste of money and weight.

Thats what my thoughts were too. Why add the wight, when LY rods will work. For $250 a brand new design 440-source "stock" press pin replacement rod with better bolts may be the way to go rather then spending money and time on reconditioning the LY's.

Again, its probably going to be a 13.5 car regardless. But prefer to build the bottom end only once and on a reasonable budget.

Which "Pure Stock"?

Closest to me was the FAST/Pure Stock in Staten. Are there others?

pump gas? or race gas?

Not sure at this point. I can go 1.5 points over stock, but will probably stick with 10/11:1. I already have 4.10 gears from another project.

Consider this:

I went with a stroker 4.25 crank, H beam rods and ightweight pistons. Overall I saved really close to 8 lbs. Total in the rotating assembly and gained 65"!

Molnar 7.1" rod, pin and Mahle piston weighs 1490 grams.

Mopar stock 6.76 rod, pin and cast piston from '73 440 forged crank motor weighs 1875 grams.

The crank was close to the same as stock (70 lbs.) Despite having 2.20 Chevy sized rod journals.

This is my point. When it come to piston selection "Pure Stock" is a long way from factory original and even NHRA Stock.

Next questions:
1) Are you going to be competing at PSMC events and want to be, or be able to be certified in conformance to the rules?

2) Do you want to be competitive?

3) What is your budget?

There can be a big difference in your cost/performance/fuel requirements depending on theses answers. There can be a world of difference in cost and performance between a true Pure Stock car, and a kinda-like a Pure Stock car.

And I guess to answer your question, you can certainly use the LY rods for your motor with the 2355 pistons, but there could be rule conflict with the rod depending on the year of your application.

Right now, its for fun. Simply to do it rather than read about or dream about, when I have an A12 unfinished, a 69 340 swinger needing total resto (which is the one I'd prefer to build for PS), and a 71 GTX that can be up and ready without paint or body work for 5-7k with a new short block....as I don't want to run with my original block.

So, again, I'm looking for a 13.5 ET on a 4000 lb car, without breaking the bank and going to an array of aftermarket parts, etc. $250 for new rods and better pistons, I can swing, when you consider quality rod bolts are $80 bucks alone.

I've looked at the 440 source rods and their "stock" replacements are press pin, but all their pistons are floating. I'll call them this week.

On the pure stock class, i'm thinking you can run a different piston, just no domes, no strokers, etc. You read the basic rules and you can see where coatings, etc, aren't covered.

Normally I'd say ditch the heavy rods. But IMO you'll get more bang or the buck by just competition balancing those heavy six pac rods and pistons than spedning for new rods and having it balanced. Your ET goals are not crazy. A decent stock longblock with a cam and bolt ons can do that. Make it smooth, and run it.