Country Boy

iTrader: (24)

Whats the big difference?

Did LS1s come with the 6.1 rods to begin with? and what advantages do the 6.125 rods have?

<small>[ October 17, 2002, 08:08 PM: Message edited by: Country Boy ]</small>

00UNTAMED

<img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" /> The stock ls1 engine came with 6.1 inch rods. The way that I understood about a longer rod is that the longer rod that u use the longer time that the chamber has to comeplete combustion. Rods do mean alot in a engine. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
So the way to go is that find the longest rod with the longest stroke and you should make the most amount of power out of your engine. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
"382ci" has a 4in stroke and a 6.125in rod!
I'll get more info for you.... <img border="0" alt="[guns]" title="" src="graemlins/gr_guns.gif" />

Fenris Ulf

This is not even a concern. Just get the strongest of the two since their rod ratios are almost equal.

Gold Phoenix

iTrader: (1)

Going to 6.125" Rod you can use a standard SBC Rod which are cheaper than a stock replacement rod.

DONAIMIAN

iTrader: (18)

i doubt that u can use a SBC rod, but i don know with the longer rod that the piston will stay at TDC fo a longer amount of time, and its really good for boosted cars.

nitrousc5

longer rod is always better and quite beneficial. first off, the longer the rod, the less the rod is perpendicular to the cylinder wall thru the piston/skirt. shorter rods accentuate this sideward force, creating more frictional losses and wear. but the biggy is that the longer the rod, the longer the dwell at TDC and BDC. i dont think i need to explain why that is good!!!

00UNTAMED

UNTAMED 00 SS back again! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Thank you "NITROUS C5" for knowing what you are talking about. You could have not said it any better!

COUNTRY BOY! You will always make more power if you have a longer rod in your engine! Even if your rod is a 1/16 of an inch longer. Yes us will notice a difference. If you don't the engine dino will! <img border="0" alt="[Burnout]" title="" src="graemlins/burnout.gif" />

00UNTAMED

UNTAMED 00 SS back again! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Thank you "NITROUS C5" for knowing what you are talking about. You could have not said it any better!

COUNTRY BOY! You will always make more power if you have a longer rod in your engine! Even if your rod is a 1/16 of an inch longer. Yes us will notice a difference. If you don't the engine dino will! <img border="0" alt="[Burnout]" title="" src="graemlins/burnout.gif" />

ZYA_LTR

Sorry STANGKILR but you can use a standard sbc rod in an LS1 you just have to have custom pistons made for the offset, and to compensate for the longer rod. I have Eagle H-Beam ESP 6.125 rods, and custom made Diamond Racing Blower Pistons in mine, and they work fine, we've done it before, and weren't the first, calll around and ask, they do it alot.

Louis

iTrader: (7)

yup, a 6.125 rod works granted you change the CH of the piston from stock <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />

00UNTAMED

UNTAMED 00 SS BACK AGAIN! <img border="0" alt="[Burnout]" title="" src="graemlins/burnout.gif" />

If the rod is 6.0 inches long and the stroke is 3.0 inches, the ratio between the two is 2:1. This is often called "the rod ratio". In alot of american v8 engines the rod ratios are about 1.65:1 to 1.75:1 the reason why that they do this is because it is a all-around good engine performance. If you want a racing engine the rod ratio should be much higher. To about 3.0:1.

A racing engine always produces more torque and horsepower when the rod ratio is increased beyond 1.75. <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" />

Try this when you rebuild your engine! Take your 6.0 inch rod and assemble it into your engine. Mount a dial indicator against the top of the piston, and place a degree wheel on the crank snout. If you place the piston near top dead center and read the dial indicator as the piston moves from 0.001-inch below /before\ the top of the stroke to 0.001-inch down /after\ the top, the degree wheel-and crank-will move through about 9-10 drgrees "about" of rotation. Then do the some job on the with a 6.125 inch rod and you will receive a much higher degree range over the some range of piston movement. In fact the longer rod will cause the piston to "dwell" longer in the vicinity of top dead center. <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" />

<img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> This is important during the crossover from compression to the socalled power stroke. <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" /> If the piston dwells longer near the top dead center and the ignition is initiated properly, there will actually be a longer period of time for the pressure created during combustion to press against the top of the piston. Increasing the piston dwell allows the pressure to build higher while the minimum cavity exists in the chamber, and this higher pressure level presses against the top of the piston during the early portion of the power stroke. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Another thing if the rod length is longer, the crank arm swings over further before before the combustion cavity begins to open. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> This increases leverage exists through the hole power phase-through it is most effective in the early portion of the stroke and the end result is a smoother engine that produces more effective work during the power stroke. This will produce more torque and more horsepower. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

00UNTAMED

<img border="0" alt="[devil]" title="" src="graemlins/gr_devil.gif" /> So just remember one thing "USE THE LONGEST DAMN CONNECTING ROD YOU CAN FIT IN THE ENGINE" <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

If you use some sort of forced air induction with a long connecting rod you will make even more horsepower. <img border="0" alt="[Burnout]" title="" src="graemlins/burnout.gif" /> Then you could change your fuel to like alcohol you can make even more power. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

So I hope that I have helped you out on your connecting rod queation! <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

Like I had said there before there is alot that we could talk about when we are refering to connecting rods.

You know that, you do not have to change your crank if you decide to rebuild your engine. You will be changing you pistions anyway. Just tell them what you are doing. Then they will sending you the right pistions for the job. Allways remember that your stock crank can handle up to 600 horsepower! Have fun!!!! <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />