I was going to use K-motion K-800 springs, they are 1.46'' dubble springs There 155 lb. closed and 625 lb. open.
Is that to much for regular flat hyd. lifters?
If that is to much should I go mechanical lifter?
This is for a SBC with 1.6 roller rockers and about .560'' lift spining about 6500 out to 7K at the most. I all ready got the del West retainers and del West super 7 locks all I need is the springs and heads (valves are in the mail).

 

Whats the spring rate on those? I dont' think you have that much pressure open with a .600 lift cam, but the seat pressure looks fine.

 

I have been running those springs for four years now with steel retainers. latest cam is a GM #847. Stock lifters have been fine so far .

They should work good for you with the Titainium retainers

 

They install at 1.85'' (155lb.), full open at 1.15'' (450lb) and they bind at 1.085''.

 

Ditto that...I was using the K-800s when I was running the Crane equivalent to the GM #847. I used a new set of Crane OEM lifters and didn't have any problems. I'm still running them with my current sissy cam (even though they're overkill at this point).

 

Is he talking about a flat tappet cam or a roller?

Rich Krause

 

crane recommends no more than 130 lbs with hyd flat lifters. I'm running 6500 rpm with 292* and 115#. Seems to pull all the way up to shift, so i dont see the need for more than that.

 

I mainly wanted to know about hyd. flat tap but would like some input on hyd. rollers too.

 

For a hydraulic flat tappet cam used on the street, I wouldn't exceed maybe 350 to, at most, 400lbs open. It's the open pressure that is limited, not the seat pressure. You could go higher with a roller. As to how much spring you need, more detailed cam specs would help. But I don't think you need as much spring as you have.

Is this a race or a street motor?

Rich Krause

 

^said by me a few days ago^.
It is to be a hot street/race engine.
I want to find some retro fit lifters that will fit a 87-up SBC or find a way machine my 89 SBC to take old style retro fit lifters.
I can't find any retro fit lifters for my engine comp and crane don't have them last time I checked.
I won't be useing all of the spring I can intall them to the inst. hight ( valves are +.100'' for intakes and +.200''for exhaust the retainers are std hight and the locks are too) and shim them to hight) and only use about .560'' of the .600'' lift they will be good for.
Looks like I'll need 2 sets of push rods.
I was going to inst. the intakes just under the inst. hight and put the exhaust valves right on the 1.85'' mark.
The exhaust have a bit more lift than the intakes and the intakes have a little more mass then the exhaust valves so I was going to give them a little more closed pressure.