'62 Ranchero - 250 - Aluminum Head update

Update:

As soon as I removed the cam gear, the camshaft dowel pin fell into the oil pan. I had to pull the oil pan off to get the dowel pin. The dowel pin is rather loose in both the old cam and new cam (about the same); I can move the dowel pin at least 1/32", and maybe as much as 1/16". Is this OK, or should I replace the dowel pin? The cost is negligible, but with the current situation I don't know how long it will take for a new one to ship to me.

If anyone here has a spare camshaft dowel pin, I will gladly pay for the pin and for expedited shipping.

Thanks
Bob
 
bettin Matt at VI would B quick (summitt too by Y go that rout).
I am an 'essential' emloyee & everybody I C 'out there' is doin their thing & wantin business.

Doesn't it sit in a 'blind hole' so no chance of fallin out? wouldn't wanna use some 'threat set' ?
 
chad":1utjiau6 said:
bettin Matt at VI would B quick (summitt too by Y go that rout).
I am an 'essential' emloyee & everybody I C 'out there' is doin their thing & wantin business.

Doesn't it sit in a 'blind hole' so no chance of fallin out? wouldn't wanna use some 'threat set' ?

It does sit in a blind hole. I think it’s supposed to be tight, but if loose it could fall out.

Thanks
Bob
 
pmuller9":161u0jce said:
Are any of your local auto parts stores open?

What are the pin dimensions?

Stores will be open tomorrow, but I don’t expect them to have the dowel pin. Summit apparently did not.

It’s 1/4” dia x 3/8” long.

Thanks
Bob
 
The part is PIONEER # PF-200

It's listed under "cylinder head dowel pin" in parts searches. It has alot of applications. If you go to the pioneer catalog and type in pf-200 under parts search then click on it and select buyers guide it will list all the years and engine applications for the pin.

http://showmetheparts.com/pioneer/
 
drag-200stang":g6d4u4rq said:
Have you thought about longer valves, like Fast 64 used on his Al head...That would be better?

So, please educate me on the advantages of longer valves - I'd have more spring height, allowing more lift before coil bind? I'd have more clearance from retainer to seal for higher lift?

Would need new springs if the valves were much longer, right?

I believe the valve/spring combo is ok for the cam I'm installing (Clay Smith 280H/110). It was five years between the original build and this upgrade; it could be several more years before any further upgrade. Just a carb upgrade could take months to sort out properly.

Thanks
Bob
 
Econoline":o1ppfc66 said:
The part is PIONEER # PF-200

It's listed under "cylinder head dowel pin" in parts searches. It has alot of applications. If you go to the pioneer catalog and type in pf-200 under parts search then click on it and select buyers guide it will list all the years and engine applications for the pin.

http://showmetheparts.com/pioneer/

@Econoline,

Thank you for this! There are so many applications (at least, four cylinders and inline sixes, maybe v-6's as well), this gives me hope that it could possibly be at some local auto supply store.

Thank you,
Bob
 
62Ranchero200":sje6vdgp said:
Econoline":sje6vdgp said:
What's your compression going to be with this combo Bob?

Funny you should mention that, I just performed this calculation, resulting in a calculated 10.614 SCR.



Thanks
Bob

I would ask that anyone who has time would check my math and let me know if I have forgotten anything or made any calculation mistakes. Am also a bit concerned about piston to valve clearance, only in the unlikely event of a timing chain failure (assume one or more valves are in the fully open position while the corresponding piston(s) reaches TDC in that cylinder). I think it would be close but may be OK.

I think combustion chamber will be about 3/8" (0.375") deep now after mill (I don't have the head back yet)
Per discussion here, compressed thickness of Fel-Pro 7916 PT-1 should be .050"
Piston is .005 down the hole
Piston dish is .129 deep (I THINK open valves will fall over dish, there is only about 1/4"-3/16" undished piston rim)
Lift will be .512 with my 1.6:1 rockers

Thanks
Bob
 
Econoline":3763ye9x said:
The part is PIONEER # PF-200

It's listed under "cylinder head dowel pin" in parts searches. It has alot of applications. If you go to the pioneer catalog and type in pf-200 under parts search then click on it and select buyers guide it will list all the years and engine applications for the pin.

http://showmetheparts.com/pioneer/

As I suspected, no local auto parts store stock this or even have it on their web site for special order. It's listed as out of stock by Rock Auto. Vintage Inlines and Clay Smith are my only hope unless some individual has a spare pin. I already know that Clay Smith is running on a skeleton crew and may not be shipping now, even for items already in stock.

Thanks
Bob
 
HI Bob, I when through your math and it looks right to me. Let's say the timing chain broke using all your above measurements I get a .049 valve to pistion clearance if the cam was at its full lift of .512 and the pistion was at TDC, what is not accounted for in this is the coefficient of thermal expansion see the below link if you want to dive into theose formulas. A Cast Aluminum head would expand at higher and faster rate than cast iron. My best guess is the valve to pistion clearance would increase some at normal engine operateing temps. In my experience I don't see much of a chance of the double roller timing chain set breaking though. Best of luck on your cam swap. (y) :nod:

:banghead: :eek:opsie: Edited :shock: yes completely forgot about the cam and Rod bolt interference that would happen if a timing chain broke, as in Xctasy's below post. You are already running a duel roller timing chain set though in your 250 aren't you?

Formulas for Thermal Expansion
https://www.engineeringtoolbox.com/line ... _1379.html
 
The valves are at a slight angle so you will need to measure from the head deck to the closest spot on the intake valve.
Then add the gasket thickness, piston dish depth and piston to block deck clearance.

The valve lift is calculated at .512 but the actual valve lift may be different.

I got 10.612 static compression ratio.
The dynamic compression ratio with the 280 cam and the intake lobe center at 106 atdc is 8.4
 
bubba22349":28lza340 said:
....The Falcon engines are a non interference engine, but let's say the timing chain broke using all your above measurements I get a .049 valve to pistion clearance if the cam was at its full lift of .512 and the pistion was at TDC, what is not accounted for in this is the coefficient of thermal expansion.
Formulas for Thermal Expansion
https://www.engineeringtoolbox.com/line ... _1379.html

The cam to conrod situation makes a US Ford 200 six and the 250 six both interference engines if the cam timing is not kept to the standard 116 degrees Lobe Center, that's Not the LCA, but the timing BTDC event.

Im an ex Mini A series guy from way back in 1993 to about 1996. The Australians used stadard BMC chain pitches, and the block is mapped out similar to the Ford 144-250 small six.


Since the Australian 200's and 250's used the same kind of Mini A series 1275 and Mike1157's 250 conversion to 5.0 timing gear also used Holden Small Block 253/308/304 Vee-Eight and the Toyota 18R timing chain, this video will help you.

As JackFish found, if the base cam blank is re-pitched wrongly during the cam grinding process, WHICH DOES HAPPEN, then you get rod to cam shaft contact. In the case the the USA 250 timing gear, both the 69-72, and later 73-80 timing gear, the timing can slip.

When checking the cam tiimg, drop the sump, and check for clearance. These engines are most certainly interfersnace for cam to conrod clearance in certain situations. The failure or slipping of cam timing can cause what English copy writer Graham Robson described as "Spectacular Disarrangement's". This was a referenace to an old Dutch Spyker term for Serious Terminal Cam to Crank Contact.

Take a little time out to preview this. The A series ran either a twin row chain, or single row chain, later on, with a tensioner, as yall will know, in serive wear is huge with the Ford single and twin row timing gear set, of any type. Its the nature of a pushrod engine, and Ford, like Morris and later BMC/British Leyland and then Austin Rover, they worked the tolerances on making a Bad Idea Work Well...


https://www.youtube.com/watch?v=rad7cdJ ... e=emb_logo

https://www.youtube.com/watch?time_continue=rad7cdJmT6k
[bbvideo=560,315]https://www.youtube.com/watch?v=rad7cdJmT6k[/bbvideo]


Part 2 of 2.

Then go through the basics, this post below is on the 200, but the same principals apply.


See viewtopic.php?f=1&t=75618&p=582243&hilit=CAM+TO+CRANK+CONTACT#p582243

You don't have to go so far or worry too much, but just Be Aware that Ford packed a lot of cubic inches in a very small space in the 144-170-187-188-200-221-250 small sixes, and the weakness is that timing chain wear then causes cam to con rod contact.


This is only on the Short deck 187-200 7.803" and tall deck 250 cubic inch 9.38-9.469" engines.

The short deck 200 and all 250's were factory Stroker engines. The rare 187 Argentina engie is an overbored 170 with a four bearing 200 crank, same issue.

Not and issue with the USA 7.803" deck 144, 170 (1960-1964, and 1960-1973)
the Argentina and Australian Medium Deck 8.425" 3.1 liter 188, 3.6 liter 221 (1968-1996 Arg, 1968-1970 Australian)

or tall deck 9.38" Australian 200 (1971-1992).

The 200 and 250's are the ultimate economy engines. Ford didn't make a mistake, they just designed them as inventory filler engines for those who didn't want SBF V8's like the 221, 260, 289, 302, 351s, 400's or gasp, the little 255 4.2. Every year from 1962 to 1983 for the 200, and 1969-1980 in the USA and Canada for the 250, they existed to fill a cost effective gap, and man, where they ever an inexpensive engine to make.

In Argentina and Australia , they were Y block 292 and Windsor 289/302/351 and Cleveland 302/351 step down options.
 
pmuller9":32pztlv3 said:
xctasy

It looks to me like the con rods are between the cam lobes, same as the big six.
viewtopic.php?p=627749#p627749
Am I not understanding your post?


Um, no, PM. Its not cam lobe to rod contact. This is not to use JackFish as a poster child, as my mates 1985 EFi Turbo Xflow 4.1 liter Fairlane AIT did exactly the same thing when the auxiliary fuel system leaned out the engine. The result was rod to cam contact after a rod was bent. It used the Buick Regal "Dutweiler" style T-Type/GN Turbo/GNX style Auxilary CFi upstream fuel adder. See xctasy fordsix.com AIT Falcon turbo computer.

The problem is generically rod verses Camshaft. Its the camshaft casting that touches cast iron rods and some forged ones as well. Sometimes the rod bolts touch the cam casting or forging.

Early 144-170 cams have no relief scoops, and the 200/250 engines have interference issues here during cam chain failure.

See viewtopic.php?t=65908

JackFish":32pztlv3 said:
Stock cam:
stockrelief01.jpg


Clay Smith:
4relief01.jpg


JackFish":32pztlv3 said:
chain01.jpg

#1 @TDC
TDC01.jpg

#6 @TDC
TDC06.jpg

The other side of the rod.
rod01.jpg
 
62Ranchero200":2zotcgp3 said:
drag-200stang":2zotcgp3 said:
Have you thought about longer valves, like Fast 64 used on his Al head...That would be better?

So, please educate me on the advantages of longer valves - I'd have more spring height, allowing more lift before coil bind? I'd have more clearance from retainer to seal for higher lift?

Would need new springs if the valves were much longer, right?

I believe the valve/spring combo is ok for the cam I'm installing (Clay Smith 280H/110). It was five years between the original build and this upgrade; it could be several more years before any further upgrade. Just a carb upgrade could take months to sort out properly.

Thanks
Bob
Yes on all the above. and more modern spring selections .
See Fast 64's... thread in the Aluminum head forum , he just when threw this and covers it well.
I posted mostly to help spread the knowledge about the Al head and the better valve length for people starting out with bare heads.
 
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