i am building a 355 lt1 for my car and i was wondering which rotating assembly would be better and what are the advantages of going with a 6.0" rod over a 5.7" rod

my motor will be in my 87 irocz with a t56 conversion. i will be using a TNT F2 kit and a mcleod twin disc clutch

option 1: eagle forged 3.48 stroke crank, with scat h beam forged 5.7" rods and a set of JE 10.5:1 pistons on a 58cc head

option 2: same except using a set of scat h beam 6.0" rods

which would be better a longer rod or a shorter one

 

There's been a lot said on this subject, but here goes again:

As Smokey Yunick might have said, "Put the longest damn rod you can fit into it". If prices are the same, go with the 6.0.

If 6.0 vs 5.7 rod is the only change, you probably won't see much difference in performance. The compression height of the piston with either rod is reasonable. The 5.3% increase in rod length isn't very significant, but every little bit helps.

If you have lots of money, and don't deck the block, you CAN put a 6.25 long rod in a 3.48 or 3.50 stroke SBC, and it will run well. Is it worth it for a street engine? Probably not.


This is probably better suited for LT1 forum. Lots more activity there.

My $.02

 

This is a good read, prevents alot of typing.

http://victorylibrary.com/mopar/rod-tech-c.htm

for the record I'm a 6.0" rod fan in that combo. If it's forged I like a 6.25" even more.

Bret

 

In my many low-buck motors I can tell you that rod length has very little effect on power production. However, the rings and bore last longer with long rods. A 350 with 6" rods will survive MANY more trips to 6500 than a 383 built with "shortie" tstyle 400 rods (5.56").

 

Moist likely the crank will to since most times there is less load on the throws due to the lighter weight piston at the end of the rod.

I've seen some 4.030 pistons for a 3.48 6" rod combo that are below 330g's

Bret