Visit The Dirt Forum for More Information

Author Topic:   6" rod advantages?
posted May 06, 2003 02:34 PM
What advantages are there to a 6" rod in a 350 Chevy?

posted May 06, 2003 02:47 PM
i think we've been over this before but..... a longer rod creates more dwell time at TDC and decreases the rod angle. more dwell time allows more time for cylinder filling and makes cam timing less critical. the decreased rod angle gives the piston more leverage on the crankshaft and decreases cylinder wear.

it's a win-win situation. a long rod engine will outperform a short rod engine of the same design every time, in my opinion...

posted May 06, 2003 09:20 PM
For those of us that have to use "stock" parts, did 6" rods come in any chev engines that couild be used in a 350 chev engine?

posted May 06, 2003 11:05 PM
ole bills had em'

rico 08
posted May 08, 2003 12:32 PM
If i read it right some of the new vortec style 4.3 motors have a 5.9 something rod but don't quote me on that.

posted May 09, 2003 02:57 PM
The most that a 6" rod can help, as compaired to a 5.7" is 2%. This number was told to me by a man who ran dynos for a large parts manufacture/supplier, who doesnt want the name published.

The Rascal
posted May 14, 2003 09:57 AM
The longer rod ratio not only increases TDC piston dwell…but decreases (comparatively) BDC dwell…but this is ok because BDC is further away from the valves and there’s far more room to play with cam timing down there…
The longer ratio also leaves TDC slower, longer, and more in the “middle” of the stroke…using restrictive ports/induction more efficiently…
The reduced cylinder wall angle is icing on the cake…anybody who…especially dyno operators…hasn’t seen favorable results has not been taking the actual design aspects into consideration…and probably still looking at cam profiles as not realated.
Mope smallblock motors start out with a 6.125 rod…and angles from 1.71 to 1.85…candy…and I just “found” a factory 6.250 rod…look out! Rascal

gerald berry jr
posted May 14, 2003 11:56 AM
less wear on pistons would be biggest benefit difference on a dyno between two identical motors just with different rods is very minimal.

Back to the Archives