97camaro383

iTrader: (31)

Im about to put the heads on my motor and I want to check PTV clearance. I seen this video saying you can use hydraulic lifts if you use checker springs, is this true or do I need solid lifters?

badazz81z28

iTrader: (6)

I didn't watch the video...but yes checker springs can be used. The only reason to use solids is because they don't bleed off with the spring high pressures. If you swap the springs out for checker springs, the hydraulic lifters will not collapse.

97camaro383

iTrader: (31)

Thats what I was needing to know! Im going to get a cam degree kit with checker springs from summit but I didn't have solid lifters. Didn't know if i'd need them. Thanks for your help!

3rdCoastPowerSports

iTrader: (5)

i have heard you can use checker spring with hydrolic lifters. I have never done it that way. I have always used solid lifters and checker springs. I have made a full set of LS7 solid lifters to use as well as a full set of checker springs now i can check everything without pulling stuff apart.

97camaro383

iTrader: (31)

That's a good idea. Hopefully I won't have to tear this motor apart for a long time.

maxpower_454

iTrader: (7)

I found solid lifters to be useless when doing my H/C build. I used solids at first to get PR length and and realized it was pointless since there is no pressure on the lifter (hyd won't collapse). Then I was using a solid for PTV. Again realized solids were pointless because the very small amount of pressure from the checker springs wouldn't make the hyd's collapse either. I'm not sure why anyone use solids. It's best to check everything using the parts you are going to install.

farmington

iTrader: (14)

if you use checker springs, don't use the clay method, use an indicator on the retainer.

mark21742

You can buy checker springs at Lowes or homedepot for about $2

97camaro383

iTrader: (31)

I planned on doing the indicator on retainer and using clay to get my radial clearance since I had to fly cut. Can you explain more why I can't use checker springs and clay.

Alvin@PCMofNC

We check P2V on every cam install we do. There are a lot of cam installs we do where we are not removing the head so yes we use checker springs and adjustable pushrod.

I'd say it would be unlikely to pump down a hydraulic lifter with a checker spring but be very easy on it and treat it as if it can happen. Know also that the pushrod length that you would normally run should push the lifter down some .030-.040 and if it can't (checker spring) it will push the valve spring down instead. That is why an adjustable pushrod is key here. You must be able to take the rocker arm to torque without pushing the checker spring down and keep the lifter at zero lash.


After we get a good reading we check the next cylinder to see if it checks the same.

Instead of using a dial indicator take some feeler gauges and set it up with how much P2V your looking for. If you can get that set of feeler gauges to fit between the valve tip and rocker arm between -15 degrees TDC to 15 degrees TDC you are good to go. Its much easier than using a dial indicator and I would argue more accurate especially when you consider your removing the chances for human error and dial indicator setup.

pauls99z28

iTrader: (32)

Interesting!!

97camaro383

iTrader: (31)

Thanks for all the info, it should definitely make checking the PTV clearance easier.

RezinTexas

here's an excerpt from my build journal for measuring PTV with checker springs. Hope this helps.

http://www.scribd.com/doc/137049285/...RAFT-20-Apr-13

dr_whigham

iTrader: (49)

Why hasn't anyone ever made a YouTube video on how to do this with LS heads?

Vetal

iTrader: (3)

Why is it it necessary to use checker springs or solid lifters to check PTV?
What if I just fix the valves (in one cylinder) with a tape, bolt down the head, and gently push valves until they touch pistons, and use feeler gauges between rocker and valve tip? Is there anything wrong with this method?

Vetal

iTrader: (3)

Why is it it necessary to use checker springs or solid lifters to check PTV?
What if I just fix the valves (in one cylinder) with a tape, bolt down the head, and gently push valves until they touch pistons, and use feeler gauges between rocker and valve tip? Is there anything wrong with this method?

JakeFusion

iTrader: (7)

Checker springs just make it easier to not drop the valve down into the bore. Plus it allows you to check the valve at installed height. It's hard to check PtV if you're just measuring free drop.

You want to be 14-6 degrees BTDC and about 6-14 ATDC since those will be your closest points. Once you are there (use a degree wheel) and test each degree as stated BTDC and ATDC - then simply zero out. Then you simply depress the rocker down to make contact with the piston. That's your clearance.

I would do with the heads fully bolted down with either the gasket you intend to run or a makeshift version with equal thickness. I also think a hyd lifter is more than adequate with checker springs. You just don't want the lifter to compress and throw off your maximum valve lift; so using the adjustable pushrod set to 0 lash is what you want.

It also makes a difference if you use a different lifter (like LS1 vs LS7 or Morel or Johnson) to check vs what you run. Eliminate as many variables as possible.

Smokin92z4

iTrader: (1)

Y'all like morel solid lifters

Vetal

iTrader: (3)

I don't have checker springs at the moment. If they are there to just hold the valve, then I could make it without them, with a little more time spent, I guess.
Valve installed height cannot ever change, because valve seats on it's seat