Thread: pistons 3.480 or 3.750

Tweet

y do the rods determine the rpm range i thought it was more like heads and cam and intake combo?

6" rods are WAY overrated especially for street/strip motor. The factory spent millions on engineering the 5.7 rods in a small block. take the money you would have spent on long rods and put into your heads.

I used to use the Broken 400 cranks for my boat anchors. Too many to count. But that's getting off of the subject this was concerned about. LOL.

????????????????

Hey Bird, the post Willy's made about not breaking a crank. That what I was refering to. 400 cranks were prone to split in half under severe conditions. There are proceedures such as naturalizing them to give them the memory they need to withstand the loads and flexing the cylinder pressures and rpms put them through. Just gotta watch which year of production you use. As far as rod length goes, it's always better to go as long as the combo can withstand. I know there will always be arguments about this theory, but think about arm wrestling somebody that's 6ft 5 and you might only stand 5ft 4. Who's got the better geometry? (I know, I know I'm always harping geometry). The pin/skirt load of the pistons are greatly reduced and the rings like not having to succumb to severe change in motion. The pistons will dwell longer at both top and bottom of the stroke travel and this allows you to play in the areas of better combustion and flame travel. These are only a few benefits of going longer rods. Mass isn't as critical for weight purposes because the engine only sees 50% of the upper end and 100% of the bottom end of the piston rod combo. Therefore you have a slight increase in mass and with a well put together assembly, it won't matter.

I just thought I would post this again......A book is worth its weight in gold.
A book I highly recommend is HOW TO BUILD MAX PERFORMANCE SMALL BLOCKS ON A BUDGET ,by David Vizzard .
This book goes into all the questions you are asking in great detail and it also gives a list of good factory parts to use and ones not to use.With this book you could probably save a couple hundred bucks on your engine and get 100 more hp out of it.... not that I am discouraging you from using the forum , I am trying to better enable you to get the answers you need by being able to ask the right questions.You are asking lots of questions which is good,thats the way to learn.
This book starts with a regular stock engine and using stock parts and adds power 1 step at a time exsplaining how one part effects another each step of the way,if the book was not so darn useful I would send you my copy

lol well i did get one of his books from the roseburg library but didnt have it for long, i think ill go and pick it up again.

The one you want is how to build max performance small block chevies on a budgett.........It deals with mostly stock parts....some of the others get into aftermarkett parts pretty quickly and leave out most of the factory parts.

yeah thats the one i got. but he modified some of the parts and for the cost to mod the parts you could go out and get those parts only a little better for a little higher price