The testing of new rods

[aafa760]

Man one thing I hate is the first burn out and run on new set of rods and pistons rings and bearings.
To many times at 800 ft 900 ft one thinks it wants to go back to the manufacture air mail.

But after 5 they understand they are to stay in side nice aluminum block and do their jobs.

At least these are only in an Blown Alcohol.

The Nitro motor well it has been calmer lately

Tucson Reunion here we come~
Bryan

[wideopen231]

personally  a set with more runs than I am comfortable makes  me nervous . New set  just makes me want   to step on it more. Butt have broken new stuff.

[hotrod316]

WE GOT 6 MINS LAST FIRE 

[noslin]

i look at classified on Insidetopalcohol and see guys mention runs on parts.

so, for rods...  (and i know it varies)  if alum. how many runs do you go before swapping and likewise with steel rods.   do you swap rod bolts at all .  say you keep for 80 runs but change rod bolts at 40 or something like that.  what do most people do. you only account for full hard passes or how do you consider half pass etc.

how does the differ between injected versus blown.  all on meth.

ty
dean

[JrFuel Hayden]

With my all iron SBC I like to change rods & bolts at about 75-80 runs. Alto because of the timing between races, last time I changed them at 100 runs. Now these are for my 10,000 rpm alky motor. If I was running lower rpm, lower HP or lower compression ratio, I could get more runs on the alum rods. i know one JF team that killed a motor with tie steel rods after around 100 runs, because he thought they would not break, Wrong,  steel rods break too after too many runs. 

Jon

[dreracecar]

For aluminum rods, one should purchase a "GO-NO GO" thread gage to test the threads in the rods.
Failure can happen at any point, but every time you torque the rod bolts you put stress loads on the threads, and that's what kills the life span. you are not running fuel and they dont have to be looked at every pass you make.
 From what Rod manuf taught me was new rods always take a set around the big end and to put 10 passes on a set of alu rods, pull them and have the big end resized, and then you can run them for a very long time

[aafa760]

Bruce
same story I got for the new GRP Fuel rods.
My new BBC rods will get checked after Tucson for bearings.
just for my comfort of course lol

[THE FRENCHTOWN FLYER]

I have broken one aluminum rod in five decades of racing. I neglected to change them and kicked one out at 294 passes (inline six, on gas).

After that I always changed them after 293 passes.


Just kidding - I switched to Oliver steel rods about ten years ago. Ran the same as with aluminum.

[wideopen231]

A lot more to it than just number of runs. RPM,piston weight,how treated. Do  you rev crap out of motor when cold,do you netrual after finish line or let motor slow car down? For me keeping check on rod bolts for stretch has always been top of list.