1.3 Rocker Arms for Cam break in

Randy Wells · 01-05-2021, 08:13 PM

I am thinking about buying a set of 1.3 Rocker arms to break the Cam in on my I/S Camaro. My question is would you need shorter push rods to do this or would the stock length work. Would make it easier then changing valve springs.

Randy Wells
I/S 5628

prostockpete1 · 01-05-2021, 09:49 PM

do racers still do the light ratio rockers / light springs these days ?. prefillng the carb with fuel / setting about 10 degrees advance timing and loading up the crankcase with a good brand of breakin oil with lots of phosphorus and zinc in the blend ( check the label if those ingredients on the bottle label ) a quick crank / firing up to a good high break in rpm should be all you need ... maybe I.m old school on this method

SDT1DYI · 01-05-2021, 10:36 PM

Several factors are involved here.
# 1 is what you cam/lifter manufacture tells you. Follow it.
Some cam manufactures will say if you keep over the nose spring pressure under 300 lbs you SHOULD be fine.
After break in, pretty easy and good insurance to inspect each lifter.

Steve Teeter STK/SS 620

Randy Wells · 01-05-2021, 10:44 PM

Quote:

Originally Posted by SDT1DYI

Several factors are involved here.
# 1 is what you cam/lifter manufacture tells you. Follow it.
Some cam manufactures will say if you keep over the nose spring pressure under 300 lbs you SHOULD be fine.
After break in, pretty easy and good insurance to inspect each lifter.

Steve Teeter STK/SS 620

Cam guy and Trend lifers both recommend under 300Lb open on the springs, we have never done that before with no problems, but not as brave as I use to be and a smaller budget. Just playing it safe.

Randy Wells
I/S 5628

Nmbr1GMfan · 01-05-2021, 10:54 PM

First time I swapped springs, huge pain. I bought 1.3 ratio rockers, way easier. The only issue I had was the pushrods hit the head where they pass through, had to really open up the hole up.

Randy Wells · 01-05-2021, 11:01 PM

Quote:

Originally Posted by Nmbr1GMfan

First time I swapped springs, huge pain. I bought 1.3 ratio rockers, way easier. The only issue I had was the pushrods hit the head where they pass through, had to really open up the hole up.

Thanks Todd, I do remember you mentioning that on your build, will be sure to check that.

Randy Wells

Alan Nyhus · 01-06-2021, 10:05 AM

Quote:

Originally Posted by Randy Wells

Cam guy and Trend lifers both recommend under 300Lb open on the springs, we have never done that before with no problems, but not as brave as I use to be and a smaller budget. Just playing it safe. Randy Wells I/S 5628

I would recommend the light spring method for break in. There's more to it than just reducing the over-the-nose pressure. Changing springs is, at the worst, a minor inconvenience when you consider how critical proper break in is. -Al

rod butcher · 01-06-2021, 10:40 AM

I would break cam in with ceramic lifters and the swap them out after warm-up and 3-4 pulls on the dyno.

01-05-2021, 08:13 PM	#1
Randy Wells Senior Member Join Date: Mar 2002 Location: Warsaw, Mo Posts: 719 Likes: 637 Liked 1,142 Times in 354 Posts	1.3 Rocker Arms for Cam break in I am thinking about buying a set of 1.3 Rocker arms to break the Cam in on my I/S Camaro. My question is would you need shorter push rods to do this or would the stock length work. Would make it easier then changing valve springs. Randy Wells I/S 5628

01-05-2021, 09:49 PM	#2
prostockpete1 Member Join Date: Mar 2012 Posts: 249 Likes: 3 Liked 86 Times in 51 Posts	Re: 1.3 Rocker Arms for Cam break in do racers still do the light ratio rockers / light springs these days ?. prefillng the carb with fuel / setting about 10 degrees advance timing and loading up the crankcase with a good brand of breakin oil with lots of phosphorus and zinc in the blend ( check the label if those ingredients on the bottle label ) a quick crank / firing up to a good high break in rpm should be all you need ... maybe I.m old school on this method

01-05-2021, 10:36 PM	#3
SDT1DYI Member Join Date: Nov 2016 Location: Indianola Washington Posts: 399 Likes: 0 Liked 453 Times in 146 Posts	Re: 1.3 Rocker Arms for Cam break in Several factors are involved here. # 1 is what you cam/lifter manufacture tells you. Follow it. Some cam manufactures will say if you keep over the nose spring pressure under 300 lbs you SHOULD be fine. After break in, pretty easy and good insurance to inspect each lifter. Steve Teeter STK/SS 620

01-05-2021, 10:54 PM	#5
Nmbr1GMfan VIP Member Join Date: Aug 2013 Posts: 1,763 Likes: 1,197 Liked 1,954 Times in 491 Posts	Re: 1.3 Rocker Arms for Cam break in First time I swapped springs, huge pain. I bought 1.3 ratio rockers, way easier. The only issue I had was the pushrods hit the head where they pass through, had to really open up the hole up. __________________ Todd Greene

01-06-2021, 10:40 AM	#8
rod butcher Member Join Date: Dec 2005 Posts: 252 Likes: 297 Liked 132 Times in 27 Posts	Re: 1.3 Rocker Arms for Cam break in I would break cam in with ceramic lifters and the swap them out after warm-up and 3-4 pulls on the dyno.