transamws6_97

iTrader: (5)

I'm just trying to get some general knowledge...I know soon enough I'll have to be rebuilding my motor since it has 150k on it and I wanna do it right. I'm pretty sure I wanna go with forged pistons but after that I'm kinda lost...

1)What's the difference in H and I beam connecting rods? Whats the advantages and disadvantages of each and what applications should they be used with?

2)I keep seeing 5.7 and 6.0 rods but I'm not sure which would be used if going w/ a 383 stroker crank.

3)What is bushed pistons pin and pressed piston pin? Advantages and disadvantages?

4)What forged steel is better to go with because I have seen 5140 steel and 4340 steel

LT1_Fireman

iTrader: (12)

1)I-beam are lighter and weaker than H-beam and unless you want to go over 550ish hp the I-beams are fine
2)you can use either length just get pistons to match
3)not sure which is better
4)If I am not wrong most ppl just go with the 4340 because it is strong enough for most anything one mill build

transamws6_97

iTrader: (5)

so since my goal will be around 425-450 rwhp and i'll prob get some nitrous for at the track so my best bet would be h beam....and after reading up i saw that the 5140 rods were only good to 500 horsepower and 6000 rpm so yeah i think 4340 is stronger

moehorsepower

iTrader: (3)

Everyone keeps saying this is good up to X horsepower, Its not the horsepower, Its the RPM you need to spin to get there, If you make 425 horses by 5800-6000 RPM, Stock rods with ARP bolts are fine with a good balance job. A lot of money is wasted on rods, cranks and such that is not needed, I would go with Forged Pistons though...

96capricemgr

iTrader: (1)

piston weight and rpm are the factors. saw some calculations on the tension put on rods with different piston weights and it was amazing the difference piston weight makes, all about inertia.

On a performance build I would just go to bushed rods, pressed require some special equipment to assemble and all shops should have it why pay extra for them to go through a little more difficult procedure when it has no benifits. Put it this way stock stuffg is pressed, performance stuff is generally bushed.

blackz93

iTrader: (2)

No they aren't. If both are 4340, the I-beams are possibly better. Some of your nicer rods are I-beams. Crower, Lunati Pro Mods, etc...

TT632

iTrader: (3)

Blackz93 is correct. I'm sure it was Eagle that started the proliferation of the H-beam rod to the general automotive public. It was basically a knock off of Carrillos H-beam if my memory serves me correctly. I can only think it was marketing more than functionality.

Given equal cross sectional area and the same material, the I-beam and the H-beam will have equal tensile and compressive strength. The I beam design will have superior bending characteristics. The H-beam may be stronger in torsion but your pistons do not impart much of a torsional load unto the rod.

Most all high end max effort rods are a variation of the I-beam design, Oliver, Crower, Lunati etc.

SincalT/A

iTrader: (16)

What kind of budget you working with? I don't think there is any need to get some of the parts mentioned with you goals stated.Hell you could rebuild the stock block and reliable achieve your goal.

Never mind stock block rebuild I reread your post and seen you are thinking +nitrous.

transamws6_97

iTrader: (5)

just for the rebuild w/ a rotating assembly, ported heads n cam, and upgrading the fuel system i'm lookin to spend around 7-8k.

TT632

iTrader: (3)

With a 7-8k budget you should be able to get a quality turn key 383 forged long block with good heads.

Any of the 4340 forged rods from Lunati, Oliver or Eagle will work beyond the power level you want.
6" rods are fairly common with 383's. I have 6" rods in both my 421 and 383.
No disadvantage with bushed rods, only good.
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