FM 246P piston

[WerbyFord]

Do you think the difference in overlap is explained by the same checking lift theory?It does make the mapping project sound more interesting doesn't it.

Yes- by definition the overlap change will EXACTLY equal the duration change as you measure at different lobe lifts on the same cam.
This even holds true when comparing different cams if their lobe separation is the same.

mapping all these old cams is worthwhile. I was generously sent a couple early 1958 cams, solid and hyd, mapping those was interesting too.

[frnkeore]

Ford seemed to like that 228 duration lobe. They also used it on the 271 HP, 289 with a 109 ICL. Lobe lift on it was .298. That's .477 x 1.6 - .018/.020 lash and .524 x 1.76 - .025. The FE C3AZ-D, ICL is 112.5

Werby, is one of your '58 cams a Edsel?

[WerbyFord]

Ford seemed to like that 228 duration lobe. They also used it on the 271 HP, 289 with a 109 ICL. Lobe lift on it was .298. That's .477 x 1.6 - .018/.020 lash and .524 x 1.76 - .025. The FE C3AZ-D, ICL is 112.5

Werby, is one of your '58 cams a Edsel?

Yes - one is the super-hot-Hi-Po early 58 solid cam, donated by Sunjet60, 203-206 at .050 as I measured it, which Gonkulates to a nearly honest 300hp 352cid if you use the EDC heads and super-hi-rise intake (ok it's about 1/4" taller) and the big AFB with the vacuum secondary before they went to the floppenvalve AFB to save money.
I've got this cam down as B8A-A.

This may have evolved into the 390/330pi cam when a little lift was added in 1961.
And that may have evolved into the hydraulic 390GT cam at 206-206 for early 1966. More exhaust duration turned it into 207-221 and the 428CJ cam.

The second 1958 cam was donated by FERoadster, and is the "cheater hot" hydraulic cam, EDD, from the early 58 361/303hp Edsel, comes out to 196-196 at .050 lobe.

That was said to idle "too rough" (really???) and is a big step hotter than the later B8A-B hydraulic at 186-186 at .050, used in grocery getters thru 1965.

Always happy to take donated factory cams and degree them for the cause!
Usually the peak lift is down a little, to be expected, but the low lift and .050 and .100 durations seem pretty dependable.

[427John]

Haha,the Mike I referred to in my posts with the 360 horse cam is Sunjet60,I know well the 58 that the early solid cam came out of.

[frnkeore]

The second 1958 cam was donated by FERoadster, and is the "cheater hot" hydraulic cam, EDD, from the early 58 361/303hp Edsel, comes out to 196-196 at .050 lobe.

That must be the cam out of my engine. This are the cam specs from my July of '57 factory repair manual:

17/59 = 256 Dur / 111 ICL
57/19 = 256 Dur / 109 ICL
.2265 cam lift

How does that compare with the cam for seat seat duration, lift and timing?

There also seems to be some difference or confusion in what the hydraulic rocker ratio is, in reading old info, like the PDF above. I've seen other specs that they are 1.76, too. My factory manual doesn't list the rocker ratio or cam lift but, does have the spring ht difference (seat & open) of .400, right for that cam lift and 1.76 @ .399.

I'm including 2 pages of the '58 Ford Repair Manual. It doesn't list the rocker ratio, either. It does give the checking, lift specs and the lobe lift is much different, .2265 vs .241, seems odd.

[chris401]

Does anyone have the cc volume of the valve pockets on this piston?.. I am building a 360 horse 352 and am having a tough time getting the spec compression.  The piston sits down in the hole .053  Even after decking the block .030. I think there is still a .015 shim gasket available otherwise I will go with the .020. Not ideal..

I posted on the other forum some time back when I measured the 352 pistons. I have no 1960 HP data, TommyT has some photos below. From my findings whether passenger car or pickup truck the FACTORY 352 cast pistons through March of 1966 were flattops without valve reliefs. The casting number on the inside is C0AE. In April of 1966 the 352's were built with cast pistons C5AE. I believe I measured 6 or 8cc total and were very very slightly taller. My information came from first time teardowns (dated bearings). For a few years the closest gap I had was a pickup truck December 1965 C0AE non valve relief piston set from a pickup and a April 1966 F-100 C5AE with reliefs. The last one I went through was a March 1966 block from a 4V 352 Galaxie. It had C0AE pistons and C6TE-G heads.

[WerbyFord]

Frnkeore,
Here are the lobe lifts from the early solid I measured.
Jives pretty well with .241 intake .244 exhaust lobe lift.
Almost no wear at the rear, where the oil is, quite a bit of wear at the front.

Lobe Lifts   I   E
1   0.232   0.229
5   0.228   0.236
2   0.234   0.230
6   wiped   0.238
3   0.242   0.242
7   0.232   0.242
4   0.240   0.244
8   0.241   0.244

Duration at .050 was about 202 intake, 206 exhaust.
Duration at .100 was about 162 intake, 167 exhaust
LSA about 112
I didnt have an early timing set to get the advance/retard.

Decent duration but really low lift, I guess they were still using flathead Ford springs.

[frnkeore]

If you run Fords timing numbers, it comes out to the intake having a 111 CL and the Ex 119, giving a 115 LSA (4° advance) and 26° over lap.

The Edsel is, with it's In 111 and Ex 109, 110 LSA (1° retard), gave 36° over lap. Maybe the "rough" idle was the result of the 10° extra overlap.

If you subtract the lash, the lift is only .008 apart and would be the same, if the early hyd rockers were 1.76.

Does anyone have a known '58 hyd rocker to measure rocker ratio?