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prostock85 03-11-2013 05:48 AM

Thanks everyone, I'm at a total loss because I have no idea what I have. I'm
Guessing the cam will have some insight. What was weird to me was the rods were installed in the 1/5/2/6/3/7/4/8 order from front to back. I thought that's how fords were done?

rmbuilder 03-11-2013 05:48 AM

Prostock,
The cam is a Comp:
Intake
281º seat
220º@.050”
.320” lobe/.544”valve/1.7

Exhaust
284º seat
224º@.050”
.333”lobe/.566” valve
This cam, matched to a 345 cc cylinder head, on a 502, makes for an interesting pairing of components.

Bob

prostock85 03-11-2013 06:09 AM


Originally Posted by rmbuilder (Post 3883488)
Prostock,
The cam is a Comp:
Intake
281º seat
220º@.050”
.320” lobe/.544”valve/1.7

Exhaust
284º seat
224º@.050”
.333”lobe/.566” valve
This cam, matched to a 345 cc cylinder head, on a 502, makes for an interesting matching of components.

Bob

Bob, any ideas what I'm left with after these specs? I'm not sure what my revs should be as well as assumed power. Somewhat of a stupid question but what's the difference between the 345 cc and 119cc listed on head specs? (I only machined and assembled turbo grand national motors so my knowledge of these things is limited.

MER Performance 03-11-2013 07:25 AM


Originally Posted by prostock85 (Post 3883465)
Running a bit rich

That's a little more than; running rich. Without actually seeing the rings, it is hard to tell. The 502s had a issue with oil control, or you are sucking oil from the intake valve. How are the deposits on the stem side of the intake valve? Clean your rings off and shoot a pic from the side so, we can see the rings and also the cylinder bore.

If you have a 345 head on a 502. I will say in a NICE way; that was a bad choice! Mr. Bob Madara, will give you his camshaft, cylinder head , combination EXPERT TECHNICAL, opinion on that subject. I respect his; camshaft and cylinder head recommendations.
Mark

prostock85 03-11-2013 07:53 AM

1 Attachment(s)

Originally Posted by MER Performance (Post 3883512)
That's a little more than; running rich. Without actually seeing the rings, it is hard to tell. The 502s had a issue with oil control, or you are sucking oil from the intake valve. How are the deposits on the stem side of the intake valve? Clean your rings off and shoot a pic from the side so, we can see the rings and also the cylinder bore.

If you have a 345 head on a 502. I will say in a NICE way; that was a bad choice! Mr. Bob Madara, will give you his camshaft, cylinder head , combination EXPERT TECHNICAL, opinion on that subject. I respect his; camshaft and cylinder head recommendations.
Mark

Can only post a pic at a time from phone.

Intake stem

prostock85 03-11-2013 07:55 AM

1 Attachment(s)
Rings

prostock85 03-11-2013 07:57 AM

1 Attachment(s)
Bore

MER Performance 03-11-2013 10:04 AM

Sorry about the piston, if see now it was not the stock one.
The intake valve, deposits are normal for something that is tired. I expected to see worst.
The rings look like they are doing their job, 2nd ring shows the shinny area on the bottom 1/2 of the ring. Deposits at 2nd ring lang, not showing much blow-by from top.
The cylinder bore, shows all the cross hatch, gone in the thrust area. How many hours since last rebuild?
Can you measure, the piston to cylinder wall clearance, check the bore for taper and excessive wear areas?
Check your ring end gap, top ring then check the 2 nd ring gap. Just curious, to see what they are.

I will have to reply later or someone else can, I have much to do.

cp5899 03-11-2013 10:21 AM

My guess is the 345 is the intake runner volume and the 119 is the combustion chamber volume.

I think the 345 head is considered big for a 502 and the cam is pretty small. So having big heads and a little cam make for an "interesting pairing of components". At least that's how I'm reading it.

prostock85 03-11-2013 02:02 PM


Originally Posted by MER Performance (Post 3883607)
Sorry about the piston, if see now it was not the stock one.
The intake valve, deposits are normal for something that is tired. I expected to see worst.
The rings look like they are doing their job, 2nd ring shows the shinny area on the bottom 1/2 of the ring. Deposits at 2nd ring lang, not showing much blow-by from top.
The cylinder bore, shows all the cross hatch, gone in the thrust area. How many hours since last rebuild?
Can you measure, the piston to cylinder wall clearance, check the bore for taper and excessive wear areas?
Check your ring end gap, top ring then check the 2 nd ring gap. Just curious, to see what they are.

I will have to reply later or someone else can, I have much to do.

I will work on that once I get home from work. Hours since rebuild are unknown. They have 390 or so in total.


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