Adjustable timing set for 250?

As far as I know there is no such thing. I wonder if FSPP is up to this one...

Poor mans solution maybe? I wonder if the stock (for different years, as I remember there are variations) plus aftermarket sets are known for what they are timed at? Is this info available?

Pricewise stock sets should go for 3 sets for $100 or am I totally wrong. Now, if there is one at zero, one at plus a few degrees and one at minus a few degrees would that be a "handful" adjustable set...timing issue covered, additional strength not offered.

Or then to play with some offset bites.

Az Coupe
is working on an adjustable timing set for the 250.
I asked him a couple of weeks ago..
I aslo asked him about a header that fits the 250..
Also being worked on.


Nathan

We've been trying to get a chain set for a couple years. But I really put the pressure on them the last time we talked. They promised they would get on it, so we will see.

Hope to hear good news soon. Thanks for the update Mike.

But for the time being; I remember reading that '69 timing set is the most aggressive (least advanced maybe). So anybody know for sure? Where is the info for the variations?

I've got '69 coming in, but that most probably is not what I want.

Thanks!

Howdy Back All:

The '69 - '72 cam timing gear set is closer to, or may be, straight up. Later pieces were altered from FoMoCo for better emissions numbers. We are waiting and hoping that Mike can get his source going on timing sets. We're hoping, not only for adjustible, but double roller as well, for durability.

My Comp cam, with NAPA quality factory replacement timing set, came out at straight up, when it was degreed. That may change depending on the source for cam and for the timing set. Either or both may be different than straight up. It is a good idea to check by degreeing your cam once installed and before buttoning up everything. As always, the devil is in the details.

Adois, David

It should be possible to broach a new keway and get real close to where you want it.

If some enterprising machinest were to make a bushing with two or three different slots and a key for the original keway. This is assuming that there is a strong timing set to start with.

Easiest way I know, but requires machining:

Mill the crank snout to 200 diameter past the front main. Re-broach for the crank key. Use the Oz 250 timing set (52 links).

Make a sleeve for the timing cover, to step down the seal bore, if no ready-made seal may be found. Run an Oz damper.

Simple processes for a machinist.

What I was suggesting was to turn down a bushing for a broach and make it a little long. Chuck it up in an indexer. Cut a keyway, rotate x number of degrees and cut slot for broach, rotate again and cut again. Remove it from the indexer and cut the excess length off.

Put a key in the keway use it to locate the sprocket on the bushing and run the broach thru both slots. An arbor press would work fine for broaching it.

You would need to know the value (adv or ret) of the original keway as measured on the engine, then figure how much degrees per tooth ( number of teeth devided by 360) It could be worked out mathmaticaly and you would have a broach for converting regular gears to 0 +2 +4 or 0 +4 +8.

This bushing and 50.00 or less on a broach and you can cut lots of gears for cheap. I wouldn't do it for just one engine but a guy like Mike could use it to fill a gap in the market.

Sory Adam, my tendancies run toward production. If I were still machining cranks I wouldn't hesitate to cut the snout.

Anybody ever thought of an adjustable dowel pin at the end of the camshaft?

As far as I understand the dowel pin does not see a lot of force. So how about grinding 50% of the pin length flat from both sides, then drill and tap a hole thru it and cut a slotted or socket set screw for it. The length of the screw would match the slot width of the cam sprocket.

8) addo, how about starting with the oz 250 timing set, and opening up the crank gear to fit the 250 snout instead of turning the 250 snout down to fit the gear? then you would just have to recut the gear keyways. might be easier.

Any news on the set? Anybody?

I'm waiting on the used sample from Simon. He's mailed it, but we went surface (sea mail) to save beans.

FWIW....We checked a few weeks ago with a timing set for a 302.
The crank sprocket was a direct fit onto the 250. It slid right on!
All that's needed is to add a few links to the chain.

So the crank sprocket is already done.
The cam sprocket is already done.
Just need the chain.

Mike is currently working on it. I would expect he'll be stocking them in a few months.
Later,
Will

302 timing set just needs the cam sprocket center hole enlargened to 1" plus the slot for the dowel pin, and the chain needs one LESS link for 250. The cam sprocket mod is not a problem but I haven't found a chain that would be the right length - I'd guess it is there already, maybe in a different brand engine.

302 chain is alot narrower so can't use any of the 250's wide sprockets.

80Stang,
We had one of Mike's 200 roller timing chain sets on hand along with one for a 302 made by the same manufacturer.
So he'll use a 200 cam gear, new, longer chain, and a 302 multi-indexed crank gear.

Piece of cake!
Will

i went out and bought a crow cams unit for 50 bucks its got up to 8 degrees advance and retard on a 2 degree increment

prostkxy":k802g50e said:

i went out and bought a crow cams unit for 50 bucks its got up to 8 degrees advance and retard on a 2 degree increment

Click to expand...

The Oz 250 is a little different than the US 250. The block is larger and cam placement is slightly further out. In addition, the US 250 crank snout is larger, actually the same as the Ford 302/5.0, so the Oz 250 parts won't fit.

Does10s":1lu0xim7 said:

80Stang,
We had one of Mike's 200 roller timing chain sets on hand along with one for a 302 made by the same manufacturer.
So he'll use a 200 cam gear, new, longer chain, and a 302 multi-indexed crank gear.

Piece of cake!
Will

Click to expand...

Great, when is it for sale?

Naah, I'm not in a hurry, just want to get things rolling and try to multi-task all the areas of the 250 rebuild. At the same time, the block is at the shop, I'm working on the pistons to be machined and so on...

BTW Will, I dropped a PM.

I've been through the prelims of this exercise as well. The chain length varies by approx 1 link compared to the Oz sets. However - all chains available seem to be in even numbered links. So, there will be some greater degree of uniqueness to the product, as it will either use a 54 or 52 link IWIS chain, not 53. That will mean upsizing or downsizing sprockets...

In the shorter term, re-broaching the crank gear on a standard set may be the best option.

Cheers, Adam.

We'll its not all that easy. Even though the crank snout is the same size for a small block and a 250ci, the tooth count is off. As we all know, the gears must have a 2 to 1 ratio, unfortunately they don't. The 250 crank gear has 19 teeth, the SBF has 21. Thus, either the cam gear needs to be larger (dia), or the crank gear smaller. So either way, it going to take a new gear. A larger cam gear won't work, as it wouldn't fit inside the timing cover. So producing the crank gear the only option, which puts us back to square one. And we didn't even bother to look to see if the alignment was correct.

The roller chain is not an issue, but from what I've been told it is fairly costly to broach a new gear, about 5 grand. So the question is, can we sell the quantities required to offset the cost of making the new gear? Or charge an extra fifty bucks per, based on 100 sets, and still sell them? Are there 100 guys willing to spend $150 per set? I know Does10 and I are good for a few sets. : : :