440 damper timing marks not correct

[grjammer]

Purchased a 77 440 "rebuilt" from a member here, and decided to go through it as I could not get any machine shop info. It was advertised as a forged crank, which it does have.
VIN pad is stamped 8T440 E, No vin number, so okay someone put a forged crank in it maybe? It is also stamped on the VIN pad with the maltese cross and a big X, so .010 under on mains and rods from factory.
Opening it up, found the counter weight stamped with M .010 and R .010. Would seem to be the original crank or a helluva coincidence? It is definitely forged, ugly and huge parting lines.
I checked bearing clearances on mains and rods, all were good, and has .020 over bearings, so was cut .010 more. ( I was told it was cut .010).
There is no casting number anywhere on the crank, so can't ID it that way.
Damper has the correct casting number for the year, and is a forged crank damper.

My problem is when I put the #1 really close to TDC, my damper timing mark is at 2 o'clock. should be like 9 or 10. The elastomer looks perfect all the way around, no deformities.
I can not find any RB that has a different timing mark location on the timing cover, but maybe there is one?
Should I just scrap the damper and buy a fluid damper? Any thoughts or ideas would be appreciated.

 

[PRH]

Maybe what you have there is a SB damper??

In any case, you need a different one…….although I wouldn’t say you “need” a fluid filled one.

 

[Demonracer]

Look into a decent priced SFI rated balancer. Someone here in FABOland probably has one, put up a "Wanted" ad.

 

[grjammer]

Not a SB damper, the casting number is correct for 77 440. I am just getting a oem style from 440 source.
Thanks for input.

 

[Carnut68]

Timing cover wrong?

 

[grjammer]

I haven't seen one with driver side timing marks.

 

[RustyRatRod]

Truck motors used forged cranks through the end of the big block run in the 1980s. Get a piston stop and find TDC.

 

[72Duster440]

440 Source has a good price on a fluid damper if that's what your looking for. Not much more than just a stock replacement. I picked one up over the winter and it fit and works great

 

[grjammer]

I am using a dial indicator with heads off for TDC, and doing the intake lobe center method to check/degree cam. I am replacing the damper with a 440 source one, and a new set of timing gears. Supposed to be a new set but had a lot of slack. My intake lobe center measurements arent matching what the spec says. 107 vs. 110. Not sure if this cam and lifter came as a kit or not. Lifter crown is at .0015 to .002 and lobe taper is .0015 so should be good. Still hunting if there is a published install other than what the intake lobe center is. This is an old nos Sealed Power HP cam replacement CS-661. Going to try and map the cam for open close values and see how close the specs are. I wonder if Sealed Power had a different value for intall but can't find any notes in the 2 sources I have for this cam. If intake duration at 50 is published at 214, and measures at 214, wouldnt that be 107 center? I know this is overkill, probably should just dot to dot run it, lol. but lots of fun to learn the cam science.

 

[PRH]

There is no correlation between duration @.050 and the installed position.

The CS-661 is a replacement for the HP 440 cam.
It should have an lsa of 115, and an intake C/L of 112-113.

 

[grjammer]

The old Summit spec and another I found both list 110 as intake lobe CL.
My measurements on the degree wheel at .050 lift on the intake lobe are 149.5 and 64.5. Added this is 214. Divided by 2 this is 107. So i need to move to 110 is my assumption. Just trying to verify.
Calculating LSA from the the spec doesnt match. 116 ex cl + 110 int cl is 226 giving an lsa of 113.
When it cools down in the garage I am going to measure BTDC and ABDC and use the formula to give actual centerlines and measured lsa. should be interesting.

 

[PRH]

If the duration @.050(at the lifter) measures 214, and you want it at 110 C/L the intake open/close points for that lift would be:
Open- 3atdc
Close- 37abdc

With a 115lsa, and the cam in at 110, that puts the ex C/L at 120…..which supposedly measures [email protected].
Exhaust events @.050-
Open- 52.5bbdc
Close- 7.5btdc

 

[grjammer]

Numbers are matching up to what specs say within a deg. Going with dot to dot after installing new timing set. Thanks for input.

 

[oldkimmer]

U will still have to re measure if u installed the new set after u did the measurements. Or did u have the new set on b4 u started to measure. Kim

 

[grjammer]

I am going to re-do it all once I get the new gear set. It is a multi keyway crank gear so I can change it if I need to. I may have more questions later on.