Billet rod?

[Honda450R]

On arc racing’s website they say that u can’t put a +.040 rod in the hemi, only non hemi (212), is there a reason for this because I know people that have shaved more than .04 off

 

[bob58o]

On arc racing’s website they say that u can’t put a +.040 rod in the hemi, only non hemi (212), is there a reason for this because I know people that have shaved more than .04 off

A +0.040" Billet Rod in the Hemi with stock flat-top piston will probably leave you with ~0.015" piston pop out.
With a 0.045" gasket, you can still maintain 0.030" piston to head clearance.
http://www.nrracing.com/product-p/com70-china.htm

Some people don't like the piston popping out higher than the deck.
I generally use a shorter rod and thinner gasket.
3.328" and 0.027" respectively.

The +0.020" Rod usually brings the piston to within 0.005" of the deck (no pop out).
With a 0.027" Head Gasket, that gives 0.032" Piston to Head clearance.

 

[Honda450R]

This clears up a lot, so I should get +.02 rod and thinner gasket, which size gasket? And how thick it stock head gasket

 

[bob58o]

This clears up a lot, so I should get +.02 rod and thinner gasket, which size gasket? And how thick it stock head gasket

You want to measure how far "in the hole" your piston sits at top dead center.

If it is 0.025" (like most Hemi's I've come across), then a +0.020" Rod puts you at 0.005" below the deck. You should get a 70mm bore, 0.027" thick head gasket.
Or you can use a stock length rod and a 70mm bore, 0.009" thick Head Gasket.

If your piston sits at 0.035" below the deck when at TDC, then you can get a +0.040" Rood and use a 70mm bore, 0.036" thick head gasket.
Or if 0.035" below the deck, you can use the +0.020" Rod and use a 70mm bore, 0.018" thick Head Gasket.

If your piston sits 0.015" below the deck, you can use a stock length rod and a 0.018" thick gasket.
Or a +0.020" Rod and a 0.036" gasket.

You want to get the piston to head clearance as close to the 0.030" minimum as possible to increase compression and efficiency of the engine. You also want to bring the piston up to be as close to "flush with the deck" as possible.

Some people like the stock style gasket. They say it provides a better seal, which might be true. I don't know. Stock head gasket thickness on a Hemi predator is like 0.041" to 0.045".

ALWAYS CHECK PISTON TO VALVE CLEARANCE WHEN USING A LONGER CONNECTING ROD OR MILLING OR USING THINNER GASKETS OR AFTERMARKET CAMSHAFTS OR RATIO ROCKERS,..... You don't want to put a long rod, thin gasket, and hot camshaft without checking piston to valve clearance. You'll likely smash the piston right into a valve.

70mm bore, 0.027" thick
https://www.nrracing.com/product-p/mls200hg.htm
ARC 6256
3.328" (+0.020" connecting rod)
http://www.arcracing.com/6256-billet-rod-hf-predator-020-3-328-x-1-191-x-709/