Originally Posted by 1Bear

Just like I started with, people run well over .600” lift all the time without immediate issues. The issues are just accelerated wear and while there are some long term engines running around, a good deal of them are not, so it’s hard to get an accurate read on all of them. So many people run the stock rockers and appear to get away with it that a whole bunch more will never even consider that there may not be anything going on there and might as well do it too. I will say that if your hell bent on sticking with the stock rockers, that the trunnion upgrade may not be a bad idea, as the stock pieces can spit bearings in an otherwise totally stock engine. It happens fairly regular, where someone finds needle bearings in their oil pan. When it comes to overlooked items, valvetrain pieces show up all the time. Very few people here in past polls and what not have ever admitted to ever even measuring spring pressure and installed heights, and instead just drop in the springs. There again, I’m not going to say it won’t run and hold together, it’s just that by doing so you are starting out with a bunch of unknowns. Your valve-train may experience early valve float due to light spring pressure, all the way up to broken springs, and at the very least you don’t have a base record of installed spring pressures to measure against down the road. Spring pressures drop ever time, especially when tortured within a fraction of their life and while you could just replace them on a regular schedule, if you measured everything for a baseline, as long as the measurements add up, you very well could re-shim them back into spec. Also by performing annual spring pressure measurements, you can also somewhat determine a rate of tension loss to help you in your decision of when replacement will become necessary. Not trying to slap anyone in the face, but how many threads have you seen that either involve pushrod length or lifter preload, it almost would seem like a black art, where it is definitely not. I can’t for the life of me can’t figure out why someone wouldn’t mind putting in the time to install a bunch of parts, but then short cut it by not putting in the little bit extra by measuring everything and making some pretty basic calculations.

Of course I guess this where Pro builders come in and what sets them apart.

Originally Posted by 1Bear

Just like I started with, people run well over .600” lift all the time without immediate issues. The issues are just accelerated wear and while there are some long term engines running around, a good deal of them are not, so it’s hard to get an accurate read on all of them. So many people run the stock rockers and appear to get away with it that a whole bunch more will never even consider that there may not be anything going on there and might as well do it too. I will say that if your hell bent on sticking with the stock rockers, that the trunnion upgrade may not be a bad idea, as the stock pieces can spit bearings in an otherwise totally stock engine. It happens fairly regular, where someone finds needle bearings in their oil pan. When it comes to overlooked items, valvetrain pieces show up all the time. Very few people here in past polls and what not have ever admitted to ever even measuring spring pressure and installed heights, and instead just drop in the springs. There again, I’m not going to say it won’t run and hold together, it’s just that by doing so you are starting out with a bunch of unknowns. Your valve-train may experience early valve float due to light spring pressure, all the way up to broken springs, and at the very least you don’t have a base record of installed spring pressures to measure against down the road. Spring pressures drop ever time, especially when tortured within a fraction of their life and while you could just replace them on a regular schedule, if you measured everything for a baseline, as long as the measurements add up, you very well could re-shim them back into spec. Also by performing annual spring pressure measurements, you can also somewhat determine a rate of tension loss to help you in your decision of when replacement will become necessary. Not trying to slap anyone in the face, but how many threads have you seen that either involve pushrod length or lifter preload, it almost would seem like a black art, where it is definitely not. I can’t for the life of me can’t figure out why someone wouldn’t mind putting in the time to install a bunch of parts, but then short cut it by not putting in the little bit extra by measuring everything and making some pretty basic calculations.

Of course I guess this where Pro builders come in and what sets them apart.

Originally Posted by skeet

good info jarrod, i like the part about spring pressures and necessary measurements as per spring height blah blah blah, yes a pro builder built my motor, i run or did run a 926 comp spring, comp garrantied this spring for the spring pressures we were using and needing, james never used these springs and was skeptical about them, well comp gave us there word its what we needed, noone else had the spring rating we needed , all clearances were mapped out, for every little horsepower generated, it was printed and done. just to have the 926 springs fail yes the 410 nitrous fed motor is done, the spring broke in 2 places, i was using rev valves which are designed to bend, but they didnt the wierdest thing is the valve was pulled from the stem ( broke off) took out the piston and distroyed the head oh yeah as for rockers, jesel was the only company that could garranty me that there rockers would be fine over 7k rpms buty at a healthy price of 1500.00 yella terra adviced me not to use them..


pics will soon follow!

427 in the making!