View Full Version : Valvetrain weight concerns with Caddy lifters


JimMueller
06-16-2007, 01:18 PM
Not sure if this belongs in Advanced or regular, but I'll start here and someone can relocate it if it's inappropriate :)

I've read a little somewhere about the Caddy racing lifters supporting a much lighter valvetrain in the endurance motors. Will the increased valvetrain mass cause longevity problems in a street/autox/road race vehicle unless I use hollow unobtainium valvetrain components instead of typical valves, dual springs, pushrods, etc?

Also, do we have specs on how much open/close spring pressure as well as lobe lift these Caddy lifters will control?

engineermike
06-17-2007, 09:48 PM
I was under the impression that the Caddy lifters were lighter than the conventional pieces, though I never could find the actual weights.

Mike

speed_demon24
06-17-2007, 09:50 PM
I think hes asking since they used the caddy lifter in engines with a light valvetrain if they will still perform in a street car with a heavier valvetrain.

Wnts2Go10O
06-17-2007, 10:22 PM
the caddy lifters are fine. just dont spin it to 8500 on a heavier valvetrain. your setup will determine how long they last, which, im sure is a long while.

DJ_951
06-18-2007, 04:29 PM
The tech department is a little out of my realm but. The spring adds the load on the lifter, that's the resistence. So what is the spring pressure on the caddy lifter - ls6 spring ie: light. The reason for a light valvetrain is so the ls6 spring can handle higher rpms and last 100k+. A heavy valvetrain isn't the worst thing you just need enough spring to control it at a given rpm. vavlefloat...... (also spring maybe lifter life)

Yeahdoug
06-18-2007, 04:43 PM
Where you want to try to save the most weight in a valvetrain is on the spring side of the rocker fulcrum. Lifter weight and pushrod weight has a little effect on your valvetrain dynamics. The biggest reason why you see light pushroads in some racing is that they are trying to achieve a "spring board" effect from them and actually storing energy in the pushrod.

Lighter is still better on that side, but for the sake of durablity sometimes not worth it.

MSURacing
06-20-2007, 09:10 AM
The lightweight lifter is not the assembly itself. The magic is inside. If you need more info, contact me.

grinder11
06-29-2007, 08:21 PM
The lightweight lifter is not the assembly itself. The magic is inside. If you need more info, contact me. I have spoken with SDPC recently about ordering a set of these for my motor. I have had some issues recently w/my Futral cam and it's questionable heat treat (Or lack thereof!) and since I had to buy a new cam, as one lobe was scored, I figured that with 30,000 miles on a Hi-Po motor, I should replace the lifters also. I did not see any unusual wear on any of the lifters, but they are stock hydraulic rollers and figured that, if nothing else, these new "Caddy" lifters might provide a little over-rev insurance, and maybe a few extra ponies over 6200 R's or so. SDPC quoted a $225.00 price for 16 of them. Pace in Ohio has stock replacements (OEM), like I have been using, for $118.00, which sounds awful cheap for even the stock pieces. You said to ask about these new Caddy lifters, so here I am!! Thanks in advance. :drive:

JimMueller
07-01-2007, 03:38 PM
The lightweight lifter is not the assembly itself. The magic is inside. If you need more info, contact me.
You have a PM.

How about the pushrod wall thickness and diameter? Will 3/8 x .08 be sufficient for a 145/390 dual spring? Should I use the recommended preload of .060 for the Caddy lifters? I read reducing the preload will help...

http://www.ls1tech.com/forums/showthread.php?t=413469