500 V864 Conversion

Everything to do with the 425, 472, and 500 inch Cadillac engines.

Re: 500 V864 Conversion

Postby shiftless » Mon Oct 31, 2005 3:08 pm

Justin - Potter's stud mounted rocker conversion requires that .350" be milled off the head where the bar bolts down. I guess to compensate for the thickness of the bar. I would take a 368 and measure the difference in height between the spring cup and the stud mount, build a bar to the thickness I wanted, then cut the head down to make this measurement the same on your 500. Keep in mind the 368 rockers are non-adjustable so you may need custom pushrods. Can't wait to see how this works.  :thumbup:
shiftless
One Sick Caddy Freak
 
Posts: 3420
Images: 3
Joined: Wed Oct 13, 2004 7:56 pm
Location: Houghton, MI

Re: 500 V864 Conversion

Postby Justin » Mon Oct 31, 2005 3:56 pm

  Hey Shiftless,

Have you talked to potter?  I havent been able to find out the dimensions of the 368 rockers.  Will they work with his rocker conversion bar?  I figured I would need custom pushrods when the machining is done and over with.  - Justin
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby stampie » Mon Oct 31, 2005 4:23 pm

I was thinking about my franklin deal and just so someone doesn't knock on my door in ten years wanting $100 here are the rules.

1)  Person claiming said franklin must be a CB7 user.

2)  Two year limit from the time of this post.

3)  Positive proof that it not only is installed but works in at least 8 and 4 cylinder mode.

That sounds reasonable to me.

Stampie
1960 Series 6200 Flat Top as the daily driver.
Cadillac King #10
CLC # 19507
www.modifiedcadillac.org
www.cadillaclasalleclub.org
www.stampie.com
User avatar
stampie
One Sick Caddy Freak
 
Posts: 1551
Joined: Thu Oct 14, 2004 12:25 am
Location: Jacksonville, FL

Re: 500 V864 Conversion

Postby Justin » Mon Oct 31, 2005 4:54 pm

  Sounds fair to me.  - Justin
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby DaveM » Mon Oct 31, 2005 8:57 pm

OK... I'm sitting here looking at these solinoids.. I took a C clamp and squeese the spring and push the fingers through the disc.... I find that it can only go up .200" to .225"  ... The book says the lift is .457-.473  and a 1.72 rocker ratio... so if I'm thinking right...these valves are opening a little bit...so now what do you guys think?
DaveM
One Sick Caddy Freak
 
Posts: 874
Images: 0
Joined: Wed Oct 20, 2004 2:03 pm
Location: Springfield MA

Re: 500 V864 Conversion

Postby KJC » Mon Oct 31, 2005 9:16 pm

I believe the rocker arm fulcrum will not even see total lobe lift ( probably around .250- .275" on a stock cam). With the pivot point now being the spot where the rocker tip and valve tip meet, there is now a cantilever action instead of a fulcrum action. If the fulcrum were located exactly in the center of the rocker, it would see about half of lobe lift (with the solenoids engaged). Since it's closer to the pushrod, it sees a little more then half. (maybe .175")
User avatar
KJC
Gearhead
 
Posts: 173
Joined: Thu Oct 14, 2004 7:03 pm
Location: Monahans,TX

Re: 500 V864 Conversion

Postby STDog » Tue Nov 01, 2005 8:02 am

DaveM wrote:OK... I'm sitting here looking at these solinoids.. I took a C clamp and squeese the spring and push the fingers through the disc.... I find that it can only go up .200" to .225"  ... The book says the lift is .457-.473  and a 1.72 rocker ratio... so if I'm thinking right...these valves are opening a little bit...so now what do you guys think?


.473 lift and 1.72 ratio means cam lobe only lifts .275. I though the Cadillac rockers wee 1.62 though.
Since the arm pivots at the valve when disconnected,  that .275 is at the pushrod end of the arm, not the normal pivot point.

What's the length of the arm, and we can calculate the lift at the original pivot point.
If you measure valve tip to pivot and pivot to pushrod we can get more accurate, and figue the max lift for a cam.
It's pretty basic trig.
User avatar
STDog
One Sick Caddy Freak
 
Posts: 4171
Images: 0
Joined: Wed Aug 03, 2005 11:53 am
Location: Rocket Town USA

Re: 500 V864 Conversion

Postby shiftless » Tue Nov 01, 2005 1:27 pm

What STDog and KJC said. The solenoid will only see a little over half lobe lift. The max cam lift is probably somewhere in the .450 - .500 range, off the top of my head. Justin, those bars will work for you if the 368 has the same distance between intake/exhaust valves as the 500 -- which I believe it does. The 368 rocker bolts may have different threads than the studs Potter uses for his conversion, so in that case you'd need to tap the holes to fit the 368 bolts. Go pick you up a set of these rockers off a 368, that will answer a lot of questions.
shiftless
One Sick Caddy Freak
 
Posts: 3420
Images: 3
Joined: Wed Oct 13, 2004 7:56 pm
Location: Houghton, MI

Re: 500 V864 Conversion

Postby Justin » Tue Nov 01, 2005 2:08 pm

  I went to the junkyard the other day and couldnt find one car with a 368 in it.  THey didnt have 1 80's caddy at least not the bigger body style cars they had the dinky ones with the 4.5's in them but that was it.  I am going to check another yard tomorrow probably and there is a guy that I bought my 368 distributer from that might have the rocker assemblies so I will probably buy them from him.  I talked to Darius but I hink he's on vacation right now.  I'm trying to get this going just not sure where I can find a pair.  Also someone made a good point I wonder how many amps are needed from the amplifier to turn these solenoids on?  I wonder if I can grab one from a v864 system and use it manually for now?  - Justin
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby shiftless » Tue Nov 01, 2005 3:10 pm

Amplifier? You mean the alternator? Not much, they aren't doing much work, just turning a metal disk against a small spring.
shiftless
One Sick Caddy Freak
 
Posts: 3420
Images: 3
Joined: Wed Oct 13, 2004 7:56 pm
Location: Houghton, MI

Re: 500 V864 Conversion

Postby Justin » Tue Nov 01, 2005 3:38 pm

  I thought I remembered someone saying something about some sort of amplifier for the solenoids.  If its not needed then I will just use the switch.  - Justin
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby STDog » Tue Nov 01, 2005 4:00 pm

shiftless wrote:Amplifier? You mean the alternator?

No, amplifier. It prevented the computer form having to drive the solenoid directly. Mainly for current limiting to the coil in the solenoid, but also som protection in the computer. That amplifier is probably just a high current /power transistor in a case with a heat sink and some biasing circuitry.

Niost computers like 5V signals with low current, and you need 12V and strong currents for solenoids. Probably 0.1-0.5A per solenoid. With 2 on the V6 circuit and 2 on the V8 circuit (if you make the V6 circuit active in V8 mode) and add som safety margin, that 0.25 to 1A. A lot for a computer to drive.

Justin, something as simple as a relay and a resistor would work if you need current limiting
If you're not using the computer then you won't need the amplifier. I'd suggest current limiting of some sort. As scarse as this solenoids are, I'd hate for you to burn one up.
User avatar
STDog
One Sick Caddy Freak
 
Posts: 4171
Images: 0
Joined: Wed Aug 03, 2005 11:53 am
Location: Rocket Town USA

Re: 500 V864 Conversion

Postby Darius » Wed Nov 02, 2005 8:21 pm

Justin wrote:  I went to the junkyard the other day and couldnt find one car with a 368 in it.  THey didnt have 1 80's caddy .... I talked to Darius but I hink he's on vacation right now.   - Justin



Justin,

I'm back in Salt Lake but last week I was out working -- not on vacation. Really busy Thursday and Friday of this week but the weekend looks good. Check out your sources by then and let me know if I need to visit the local pick n pull.

Darius
User avatar
Darius
One Sick Caddy Freak
 
Posts: 2646
Joined: Fri Oct 15, 2004 10:24 am

Re: 500 V864 Conversion

Postby shiftless » Wed Nov 02, 2005 8:24 pm

Last time I was at the pick n pull, I saw no less than three 864 carswith solenoids intact, too bad I didn't have the cash or time or I woulda snagged em.
shiftless
One Sick Caddy Freak
 
Posts: 3420
Images: 3
Joined: Wed Oct 13, 2004 7:56 pm
Location: Houghton, MI

Re: 500 V864 Conversion

Postby Clay » Wed Nov 02, 2005 9:58 pm

O.K, some info on the 368 valve train setup.
The bolts that mount the rockers are 5/16 inch. The bolts go into the head 1/2 inch.
Valve spacing is the same for all Cad big blocks. Rockers are mounted on hardened U-shaped square pedestals which tie the intake and exhaust together for strength. The solenoid ones also are tied together on top .
Potter's bars may not work because the stud is at least 3/8 which is too large to mount the U-shaped stands. If the stud is removed the hole is already too large. Also the heads of the mounting bolts  for the bars sit above the surface of the plane that the U-mounts must sit on. The U-mounts span these mounting bolts which happen to be between each set of valves.
Perhaps the U-mount could be cut in half on the base and then clocked away from the plate mounting bolt.
Also to restrengthen the setup aftering cutting the base a top ty-bar like in the old's engines could be used.If a person got really inovative a girdle tying all of the rockers together might work because the 5/16 bolts are pretty light. :twocents: This system is certainly do-able given a little time.
Clay
Last edited by Clay on Thu Nov 03, 2005 6:27 pm, edited 1 time in total.
Clay
Gearhead
 
Posts: 103
Joined: Wed Oct 26, 2005 9:21 pm
Location: Kelowna, B.C.

Re: 500 V864 Conversion

Postby Justin » Thu Nov 03, 2005 10:26 am

  Well I found a guy online that has a v864 368 that he's parting out.  He sent me a picture of one of the heads with the vavle cover off.  What do you guys think?  He said the motor has been sitting outside for a long time.  I wonder if everything is still good.  How does it look to you guys?  - Justin
Attachments
v864.jpg
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby shiftless » Thu Nov 03, 2005 11:07 am

If the valve covers were on it should be alright. Get *all* the rockers and the valve covers as well.
shiftless
One Sick Caddy Freak
 
Posts: 3420
Images: 3
Joined: Wed Oct 13, 2004 7:56 pm
Location: Houghton, MI

Re: 500 V864 Conversion

Postby Justin » Thu Nov 03, 2005 11:47 am

  Ya I guess the valvecover in the picture is cracked.  Should I have him send the springs to?  - Justin
User avatar
Justin
One Sick Caddy Freak
 
Posts: 695
Joined: Fri Oct 15, 2004 4:03 pm

Re: 500 V864 Conversion

Postby STDog » Thu Nov 03, 2005 12:07 pm

Justin wrote:  Ya I guess the valvecover in the picture is cracked.  Should I have him send the springs to?  - Justin


hy not just get the heads w/ the valcovers and everything else.

How do those heads compare to the 472/500 heads? I know they are mid-sized chanbers (like 96cc). But with the right pistons  :scratchchin:
User avatar
STDog
One Sick Caddy Freak
 
Posts: 4171
Images: 0
Joined: Wed Aug 03, 2005 11:53 am
Location: Rocket Town USA

Re: 500 V864 Conversion

Postby Chris S » Thu Nov 03, 2005 2:26 pm

The flow really sucks on those heads, that's why nobody uses them.  But depending on what you are building for, why not?  Not like we are talking about total performance here.
Chris S
One Sick Caddy Freak
 
Posts: 1621
Images: 0
Joined: Thu Oct 14, 2004 6:50 am

PreviousNext

Return to Big Block Cadillacs

Who is online

Users browsing this forum: Bruce Marihugh, Mike P and 5 guests