What are your thoughts on Crane’s specific recommendation for 1 to 1 ½ turns preload on their performance HR lifters?

Additionally, if 1/4 turn of preload is about .015", then a full-turn would be .060". The engine is 0-deck height, however, the pistons have valve relief cuts. So, if the lifters pump-up fully we’re only talking about an addition .045” additional lift. Is that .045” going to be enough to actually hit the piston? Also, with my engine on TDC during the valve change, the valves (both E & I) had to drop almost ¼ inch to touch the piston.

WD

 

Don't know if they would hit or not. The valves are closest on the exhaust stroke,the piston chases the E valve closed.
It will take longer for them to pump down too @ 1 turn.
Ya can treat those lifters just like stock ones. Ya know the factory says 1to1-1/4 turn and ya adjust them to 1/8-1/4 turn.
If ya don't ever float the valves it doesn't matter where ya set them. Some valve float can not be heard or felt, the car just don't run right.Thats why I said it is better to over spring as some springs loose as much as 25# seat and nose pressure after a few heat cycles. They all loose some,but some loose more than others.
Lets say ya want 135 on the seat---- then ya buy a spring that is advertised at 150/155@???? installed height. The spring maker can tell ya if the advertised rate/pressure is with or without that loss.

 

Is this like your crane lifters? If so I found that less works better, at least with high seat pressure. I'm running 165lb on the seat and they've held up for about 4000 miles so far.

 

Mine are Crane part number 10535-16 that use the stock alignment bars. A roller-lifter looks like any roller-lifter, so I can't really tell from the photo. The piston lock-clip looks different

I guess I'm going to try one full-turn preload as Crane recommends for these lifters and see what happens. I can always readjust the preload.

WD

 

There are probably only 2/3 big companies that manufacture lifters for everybody. They just have their name on them(Crane,Comp,ect) after being made. There may be a special design from a particular Co. like Morel but the rest are generic.

 

The Crane catalog shows two different hydraulic roller lifters. Their OEM replacement lifter and the high-performance ones they list for high-lift cams and/or small base-circle.

I just finished adjusting them to one full turn of preload. It will be next month before the track opens again.

WD

 

Did the Crane tech ask what size stud you were running?

 

Yes. And, from my calculations with a 3/8" stud and 20 TPI, a full turn would be about .060" preload (I don't believe you typically use the rocker ratio when calculating the preload).

The tech person at Crane “insisted” the Crane performance lifters I have should have 1 to 1 ½ turns of preload. Also, the tech person said the additional preload should improve or fix my high RPM issue.

Additionally, I’ve read that minimal preload provides better low RPM performance and increased preload provides better high RPM performance. Something to think about. I’ve got them at one turn now, so we’ll see what happens when the track opens next month. I can always go to less preload if the performance falls off.

WD

 

Think about it---- it doesn't matter if it is 1/8 or 1 turn the clearance is 0.000 has nothing to do with lift or duration of the cam to effect performance.
I gotta raise the BS flag on that one.
Some set them 1/4 turn off of the BOTTOM of the lifter too but I haven't seen a tenth out of it.
The only thing it effects is how far the valve is hung open if ya float the valves,period.That is where the 1/8th turn setting came from,to try to decrease the hold open and time for recovery on the pump down.0.000 is 0.000.
The factory sets them at 1-1/2 turns for wear.

 

An engineer, I'm not. Someone who puts their mouth were the dyno was, I am.

From life experiences very few people actually make things......a lot sell them. From that, I do believe most lifters are closer than different. However, after spending a whole day on the dyno trying different preloads on hydraulic lifters, the amount of adjustment making more power is the real deal. Typicall less is best.

To be honest it was about ten years ago and don't remember the exact numbers, but believe 20 hp from just adjustment is a fair statement during our testing that day. No dope.

 

Can't see the 20HP from 1 turn to 1/8 turn unless your one turn was not allowed to settle or you had some valve float/light spring issues.
It takes a certain amount of pressure on the lifter to get it to work properly.
If the V train was getting ANY separation then the lifter will pump up to take up the slack. If the separation was not more than the 1/8 turn gives ya then of course if it pumped up it wouldn't be as much/or not holding the valve off of the seat.

 

I saw........... Wasn't the Pro Version of Performance Trends, but $300.00 worth of dyno time and a whole Saturday with a bunch of DFW F-body people watching. May have to dig up some old dyno sheets if you think not.

 

You may have gained the 20 not saying that.
Saying there was something else wrong in the valve train(oil pressure,spring presser,etc) and not the lifter adjustment.
If that 1/8th turn thing was true all the factories would be setting theirs at 1/8 turn.They don't and there are a lot smarter people than me to determine these settings.
The ONLY way the lifter will pump up is slack in the train or oil pressure overriding the load the spring puts on it or a bad check ball in the lifters or a poor design.

 

LMFAO!!!!!!!!!!!!!!!!


Denny, gotta love ya dude. Nothing like ACTUALLY doing hands on with a REAL car, instead of a dyno SIMULATION program and dream cars running here, there and everywhere!!!!!!!!!!!

Oh MY GOD I will smile all day long on that one.

Everyone I know has picked up power with the least amt of preload you can get away with on a hydraulic lifter. I have no idea why, it just happens that way.


You have done more REAL WORLD dyno testing and have probably more REAL data than anyone on this board. You have spent more on dyno time than some have spent on their engines.



David

 

I'm still not sure why Crane is recommending 1 full turn to 1 1/2 turns for thier performance lifters????????.

WD