does this make any sense to you.
03-12-2014, 08:43 AM
#1
Le Mans Master
Thread Starter
does this make any sense to you.
The rod manufactures say that on the exhaust stroke its very hard on the rod when it gets to the top has to pull the piston weight momentum back to change direction. This is where more rods fail. The 302 SBC dome piston with the 5.70 rods, a dome, most likely the heavy TRW brand of the day, had to give the rod and rod bolts a real work out on that exhaust stroke. My 69 had 3/8 bolts, what ever the grade of rod material was back then. I only put 36,000 miles on the car from new. But it was constantly being run at 4000 to 7500 + everywhere it went. Yes the cam profile was very mild compared to today, but then the single spring on it I suppose nothing in quality compared to todays valve springs whether its a single behive or whatever you may choose. The single spring being high reved all the time still doing the job when the car went, did not break.
But back to rods. I want a 6.125 rod, the piston and pin weight will be nothing compared to the old 302 piston and pin.
The scat 4340 pro rod for less then $350.00 seems like it would be light yrs better then the olden days. Seems like you would have to have one hell of an engine to need more.
But back to rods. I want a 6.125 rod, the piston and pin weight will be nothing compared to the old 302 piston and pin.
The scat 4340 pro rod for less then $350.00 seems like it would be light yrs better then the olden days. Seems like you would have to have one hell of an engine to need more.
Last edited by Little Mouse; 03-12-2014 at 08:48 AM.
03-13-2014, 08:03 AM
#2
Burning Brakes
No expert, but that does make sense to me. It's the only time the bolts take the load of the piston.
03-13-2014, 11:24 AM
#4
Drifting
The rod manufactures say that on the exhaust stroke its very hard on the rod when it gets to the top has to pull the piston weight momentum back to change direction. This is where more rods fail. The 302 SBC dome piston with the 5.70 rods, a dome, most likely the heavy TRW brand of the day, had to give the rod and rod bolts a real work out on that exhaust stroke. My 69 had 3/8 bolts, what ever the grade of rod material was back then. I only put 36,000 miles on the car from new. But it was constantly being run at 4000 to 7500 + everywhere it went. Yes the cam profile was very mild compared to today, but then the single spring on it I suppose nothing in quality compared to todays valve springs whether its a single behive or whatever you may choose. The single spring being high reved all the time still doing the job when the car went, did not break.
But back to rods. I want a 6.125 rod, the piston and pin weight will be nothing compared to the old 302 piston and pin.
The scat 4340 pro rod for less then $350.00 seems like it would be light yrs better then the olden days. Seems like you would have to have one hell of an engine to need more.
But back to rods. I want a 6.125 rod, the piston and pin weight will be nothing compared to the old 302 piston and pin.
The scat 4340 pro rod for less then $350.00 seems like it would be light yrs better then the olden days. Seems like you would have to have one hell of an engine to need more.
03-13-2014, 12:14 PM
#5
Le Mans Master
Thread Starter
I have a set of long H beam eagles 660 grams (to heavy not needed now) the scat pro rod 610 grams. Now going to order a set of eagle H beam light weight 555 grams, keep the piston pin weight low. Gkull had better be wrong on eagle junk or I'm in heavy dog turds again. a small engine build, I love pain
