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RB440 con rods

RB440 con rods

RB440 con rods

(OP)
Can you run free floating pins without bushings (1/8" oil hole drilled in top) in stock steel LY rods. If so, will they be durable enough for a mild (450hp/6000rpm max) street engine or is this a race only modification.

RE: RB440 con rods

it will only work for a short period at best

its never good to put steel against steel
even with a little oil splash

everytime i've seen it done, it wasn't long before
the pin and rod started galling each other


have the small ends of the rod "Bushed" with Bronze-alloy bushing

if you don't want the bronze-bushing , then you should run
.0008" tenthousandths to .001" thousandths pin to rod clearance if its steel-against-steel

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
http://www.mindspring.com/~meauxracing/
     Support Israel - Genesis 12:3

RE: RB440 con rods

Busboy--You list yourself as 'aeronautics'  Would you fly in a single engine plane equipped as you describe?

Why would you take an engine apart and CHEAP out on putting a bushing in the rod end?  Dumb, dumb, dumb.  Larry is too nice a guy and a good God fearing man to tell you that if you do this---YOU ARE AN IDIOT!!!


Rod----Hey, I just calls 'em like I seez 'em!

RE: RB440 con rods

Apart from the god awful noise the engine will make (it will sound like a jack hammer) You will probably break the rod at the small end (probably the oil hole). I have designed a few rods and have never even heard of someone wanting to do this... it's a joke right?


Good luck... you'll need it

www.fea-uk.co.uk

RE: RB440 con rods

GM sort of did this a very long time ago ,
mostly on steel BBC Chevy rods ,
GM tin/lead plated or dipped small ends , then honed
to size


i think GM also briefly offered same-process rods for small block Chevy

i know the BBC plated rods worked a little longer than steel-on-steel ..but the results were the same ,
pin and rod small end galling each other
it just took longer to happen with GM plated rod-ends

The Bronze bushing is the way to go with a steel rod
if you want to float small ends

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
http://www.mindspring.com/~meauxracing/
     Support Israel - Genesis 12:3

RE: RB440 con rods

(OP)
Thanks for the info folks.  I am new to the mechanical/engineering side of things so to me there's no such thing as a dumb question.  I will go with the bushings.

RE: RB440 con rods

Good man!  Go buy yourself a good book on engine building---Carrol Smith has MANY good books on all sorts of things automotive---READ, READ, READ!!!
There is absolutely no substitute for hands on experience but you can avail yourself of many years of practical work by those of us who have 'been there, done that'!  Don't try to reinvent the WHEEL! (At least not for a   while)

Good luck.


Rod

RE: RB440 con rods

one more thing BusBoy

if you are "floating" the small-end of the rod
for a "gain" in HP/Torque ??.....there won't be any !!!

the only reason to float the rods is if there were aluminum or a steel rod (with a bushing)
...other than that , it would be for easy disassembly or assembly ...because theres no HP/Torque gains !!!

if the rods are "heated on" pistons , if its done correctly
it usually takes 1.5 to 4.0 tons of force to press pin back out of piston

with the millions of engines all the car manufacturers have made,  what percent of them has ever had the pins
get loose and score the cylinder walls ???

probably a very tiny percent of a percent

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
http://www.mindspring.com/~meauxracing/
     Support Israel - Genesis 12:3

RE: RB440 con rods

(OP)
I am using Edlebrock aluminum heads for my 440 build up. Can aluminum heads be run at a higher compression ratio than their steel counterparts?  What is the highest CR I can run with them using pump gas (94 octane) and not get into detonation problems?

RE: RB440 con rods

aluminum heads usually can run a little more CR

max CR you can run ??? 92/93 octane= depends upon cam duration @ .050, centers/overlap, rpm, velocity, etc.

usually a real 10:1 cr can run 92/93 gas with 230 @ .050
pretty safely

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
http://www.mindspring.com/~meauxracing/
     Support Israel - Genesis 12:3

RE: RB440 con rods

Hey Busboy,
     Before you spend a lot of money reworking those LY rods, you might check out some aftermarket models.  I've got some Manley Sportsmasters ($499), and I've seen some H beams from various sources for even less.  By the time you have the stock rods bushed, honed, resized, shotpeened and new bolts installed, you could have almost bought a good set, and would have the added strength and assurance.  Just my two bits.
Tom  :o)

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