LS3 1.85 Rocker Test
09-19-2018, 11:16 PM
#21
I ran SLP 1.85 rockers for 9yrs...they are identical to stock rockers other then the push rod cup is relocated to increase the ratio. I will say I am surprised the PSI springs are not keeping things in control with that setup.
09-20-2018, 06:51 AM
#22
That reading comprehension though
That's why its interesting to me....everyone sings the praises of the PSI1511's, yet it can't handle a stock cam with 1.85 rockers, especially with Ti retainers?
BASICALLY A MAX EFFORT STOCK HEADS CAM CAR
Icreasing rocker ratio increases lift and duration at the valve along with jerk rate intensity...It most likely needs more valve spring pressure.
I ran SLP 1.85 rockers for 9yrs...they are identical to stock rockers other then the push rod cup is relocated to increase the ratio. I will say I am surprised the PSI springs are not keeping things in control with that setup.
I ran SLP 1.85 rockers for 9yrs...they are identical to stock rockers other then the push rod cup is relocated to increase the ratio. I will say I am surprised the PSI springs are not keeping things in control with that setup.
09-20-2018, 08:34 AM
#23
10 Second Club
Icreasing rocker ratio increases lift and duration at the valve along with jerk rate intensity...It most likely needs more valve spring pressure.
I ran SLP 1.85 rockers for 9yrs...they are identical to stock rockers other then the push rod cup is relocated to increase the ratio. I will say I am surprised the PSI springs are not keeping things in control with that setup.
I ran SLP 1.85 rockers for 9yrs...they are identical to stock rockers other then the push rod cup is relocated to increase the ratio. I will say I am surprised the PSI springs are not keeping things in control with that setup.
Also so I’ve read that Stock rockers are actually a rising rate ratio and YT’s are a constant ratio. So the valve acceleration near seat would be faster with the rollers than the stockers. I’d like to see this re done with better valve control and see what happens
09-20-2018, 08:52 AM
#24
Right...duration increases at the valve @ .050
My mistake, I thought OP was using SLP 1.85's. Didn't realize Yella Terra made a 1.85 ratio. Yella Terra are heavier then stock for sure. I would be interested to see what set of SLP 1.85's look like in comparison on the Dyno. On my LS1 w stock cam it made more power and torque through the entire curve over stock 1.7's.
Agree on further testing with better valve control.
My mistake, I thought OP was using SLP 1.85's. Didn't realize Yella Terra made a 1.85 ratio. Yella Terra are heavier then stock for sure. I would be interested to see what set of SLP 1.85's look like in comparison on the Dyno. On my LS1 w stock cam it made more power and torque through the entire curve over stock 1.7's.
Agree on further testing with better valve control.
09-20-2018, 09:35 AM
#25
TECH Senior Member
Yella Terras are aluminum. Are they still heavier than the steel rockers?
09-20-2018, 11:02 AM
#27
10 Second Club
Thread Starter
I dropped almost a pound out of swapping springs and retainers. These are the ultra light version. Really it is a combination of valve control and the stock cam just saying screw you i dont want the air. Needless to say with the mid length runner fast it still increased power from 6600 to 7100 by 25. Not sure what configuration the car will be ran at my rental on 11/6. I have .660 springs coming that are 155lbs on the seat compared to the 130lbs of the 1511s. I could shim the springs but I am not going to waste the time doing so. I just wanted to show my results and help anyone who was considering a high ratio rocker on a stock cam.
