Adjustable Cam Timing Gear fitment

JerryL · Post by **JerryL** » Tue Sep 02, 14 2:22 pm

Unfortunately, on dismantling my Facel engine (383 cid BB circa 1960) I did not take proper note of the cam gear fitment, only taking this picture:

The timing gear is obviously of the adjustable type and the clowns who first rebuilt this engine did not know how to fit it either, resulting in piston - valve contact. Not serious for the pistons but I still had to replace some of the inlet valves.

So I need advice on proper position for the cam gear on replacement.

The crank gear has not been removed and the key is in the 0° position....

....... on the inner scale.

My question is: to which point (presumably on the outer scale?) should I line up the dot on the cam gear?

Logic would say to the 0° position again ............... but is that right?

Advice appreciated, thanks. (I've tried to find instructions on the Net - to no avail).

Dave999 · Post by **Dave999** » Tue Sep 02, 14 7:12 pm

most have dots on the teeth, and you would line the both up nose to nose

you can't see the dots if the chain is over them

different gears on cranks have different standards

0* on the inner may well be the position

but i'd be inclined to install and check the poistion of max lift on no. 1 inlet against the cam card if you know the cam manufacturer.

or dial in the cam fully using one of the other methods

check comp cams web page for a detailed method.

Dave

Dave999 · Post by **Dave999** » Tue Sep 02, 14 7:19 pm

thus

http://www.compcams.com/technical/instr ... es/145.pdf

Dave999 · Post by **Dave999** » Tue Sep 02, 14 7:24 pm

cams have numbers on

if its a mopar performance or standard cam somebody will recognise.

timeing set could be anything

but popular dual roller sets are made by rollmaster, cloys etc

if its a rollmaster/Romec i have some insructions somewhere

Dave

Pete · Post by **Pete** » Tue Sep 02, 14 8:02 pm

I think many people on this site have learned (sometimes the hard way) that often the timing marks cannot be trusted - it is not just a case of "Joining the Dots" and the only safe way is to degree the cam in against the cam card (or web search...) and this involves a dial gauge and a solid lifter to ensure the can timing conforms to the specification. Often if you fail to do this the cam actually ends up retarded and this will lead to unsolvable Over-heating issues......

Blue · Post by **Blue** » Tue Sep 02, 14 8:43 pm

Yep been there! In the past if I was fitting a mild hydraulic cam I would just match the dots, jobs a goodun never had a problem.
Until a few years ago.
Fitted a mild hydraulic in my 440 with a Cloyes timing set, could I keep that thing cool? could I arse!
After much time and expense working with the cooling system in desperation I tore it down and degreed the cam, 6 degrees retarded.
Borrowed 2 other new Cloyes timing sets and each one had the crank slot in a different place and not one of them was right. I used an offset bush to correct the one that was the least wrong and it ran perfectly cool after that. After that if I change a cam or a timing set I degree it to be sure it's correct.
I only ever use good quality billet timing sets now and I've yet to find one that's not correct out of the box.
Fail to degree or use cheap timing sets at your peril! I'm sure theres loads of cars running around that perform poorly or get hot because of cheap timing sets that haven't been checked.

JerryL · Post by **JerryL** » Tue Sep 02, 14 9:17 pm

Thanks for the info guys. I downloaded the instructions thanks Dave.

I have no idea what cam is installed. The timing gear seems to be of Ausy manufacture judging by the kangaroo stamped on the crank gear (stands to reason as the engine was re-built down under).

I have been unable to extract any information about the parts used in that rebuild.

I will try to ID the cam so I can get some info on it, but seems most likely to be a standard Mopar item .................. but maybe not

Without spec for the cam and no solid lifter in my back pocket, it will be difficult to check the timing.

Pete · Post by **Pete** » Tue Sep 02, 14 9:21 pm

Possibly a "Rollmaster" so that is good news.....a very good quality set if that is the case.......

Blue · Post by **Blue** » Tue Sep 02, 14 9:32 pm

If the cam is an unknown quantity, you can find the point of maximum lift and install it "straight up" which means neither advanced or retarded.
The marks on the bottom cog work like this,
if you install in key way marked 0, use 0 on the outer edge to line up with the mark on the top cog, and so on for the other marks, + is advanced - is retarded. 0 would be the straight up position.

Dave999 · Post by **Dave999** » Wed Sep 03, 14 12:02 pm

http://www.romac.com.au/Std_&_Offset_Crank_Info.pdf

fine aussie RollMaster timing sets with german iswis chains amongst other stuff

http://www.romac.com.au/Tech.html

they also do nice race approved balancers

Dave999 · Post by **Dave999** » Wed Sep 03, 14 12:56 pm

solid lifter

take a hydrulic lifter

get some plyers

take out the snap ring in the top

pull out the middle with a self tapping screw applied lightly to whatver hole is in the top plate or it might just fall out depends on design

take out the valve n guts. help them out by applying WD40 down pipe to oil hole in side

remove spring

if you want to check gemoetry you can shim it with washers or a ball bearing so the top plate/seat is near as damn it at the top

i wouldn't bother just for cam dial in all you need to see is 0.x inches of lift on the ramp. as the lobe is coming up and going down

obvioulsy with 1/4 inch lash this is not going to work measured at the rocker unless you shim

put it all back without spring

jobs a goodun

then put the spring back when done

make sure you note what way up the metering plate under the pushrod seat goes in they have a swage to em that differs from 1 side to the other (hump on 1 side is a ditch on the other)

Dave

JerryL · Post by **JerryL** » Wed Sep 03, 14 8:59 pm

Thanks for info again Dave.

Thanks Blue, good to get this confirmation. I will try to get my brain round those Rollmaster instructions, head scratching required.

Not sure my gear is Rollmaster. I don't see the kangaroo marking on their site/gear.

On another project for a short while.

Blue · Post by **Blue** » Wed Sep 03, 14 9:02 pm

Certainly looks like a roll master, or a 440 source knockoff, they are both good quality

JerryL · Post by **JerryL** » Thu Sep 25, 14 5:31 pm

Ah Ha

Reassembly of my engine is at last proceeding having been delayed by lots of pleasant family matters

On cleaning up my timing gear I have found that it is a JP Performance 5989 timing set.

http://www.jp.com.au/Performance.html