[Johnny406]

I am freshening up my old 406 for my 65 LeMans project and I am going to install a little Elgin E-980-P. It does not have a typical cam card so my question is, how can you tell how much if any advance is ground in this cam? Here are the specs:

E-980-P Details
Range Part Number Direction Cam Int Valve Int Advdur Int Timdur Int Open Int Close Int Overlap Lash Int Center Int Cyl Footnote
C E-980-P INT .296 .444 288° 214° -1° BTC 35° ABC 69° HYD 108° 8
EXH .311 .466 298° 224° 48° BBC -4° ATC 116°

Thank you,
John

[screamingchief]

(ICL + ECL = ___ ) ÷ 2 = LSA

LSA - ICL = amount cam is advanced

(108 + 116 = 224) ÷ 2 = 114

114 - 108 = 6

So the valve timing numbers tend to suggest that the cam is ground with 6° of advance.

HTH

Bret P.

[Johnny406]

Thank you so much Bret, it sure does!!

[rick840]

Bret forgive me:
224 devided by 2 is 112 so
112 -108 = 4
4 degrees advance

Rick

[P@blo]

That's the number my Summit 2801 was stamped with.

[screamingchief]

Originally Posted by rick840

Bret forgive me:
224 devided by 2 is 112 so
112 -108 = 4
4 degrees advance

Rick

Yep,you're 100% right,that's my bad.

In my defense,it was kinda late,-and- I was posting that in a hurry.

Also been so busy & hectic around here lately that I've had a hard time concentrating on much of anything,let alone keep my math straight,LOL.

Oh yeah,note that it's spelled divided,not devided.

BTW,as a side note to that,those valve event timing numbers are for the .050" duration.
(-1° BTDC/35° ABDC/48° BBDC/-4° ATDC)

Seat events for 288°/298° adv. dur. would be:
(36°BTDC/72°ABDC/85° BBDC/33° ATDC).

Originally Posted by P@blo

That's the number my Summit 2801 was stamped with.

That's because they are the same cam,almost certainly made by the same cam co. as each other,just being marketed by numerous other vendors under their own name,it's reboxing parts @ it's finest.

Now you say,,,but Bret the advertised duration numbers are different between the two cams???

That's all just smoke & mirrors to make each cam co. blur the fact that it's pretty much the same exact cam that everyone else is out there selling,one co. rates theirs @ .006" per SAE (say Summit),and the next co. (say Elgin) rates theirs @ .004" or even .002" instead,as there is no real "standard" where each cam gets it's advertised duration rated at,one looks to be slightly "bigger" than the other due to the perception that it has more advertised duration than the other one has,but truth is they're the same cam.

This cam:
Brand & part no.: Elgin #E-980-P
Grind & lobe no.:
Tappet type: hydraulic Flat Tappet
Spec = intake/exhaust: (notes)
Adv.dur. = 288°/298° (I/E split = 10°) (Adv.dur. rated @ ???)
Dur. @ .050" = 214°/224° (I/E split = 10°)
Lobe lift = .296"/.311"
Lift @ 1.5 rr. = .444"/.466"
LSA = 112° ICL = 108° ECL = 116°

Advertised/seat events:
IO = 36° BTDC
IC = 72° ABDC
EO = 85° BBDC
EC = 33° ATDC
Total OL = 69°

.050" events:
IO = -1° BTDC (1° ABDC)
IC = 35° ABDC
EO = 48° BBDC
EC = -4° ATDC (4° BTDC)
OL @ .050" = -5°

The specs I have for the Summit 2801:

Brand & part no.: SUM - 2801
Grind & lobe no.:
Tappet type: Hydraulic Flat Tappet
Spec = intake/exhaust: (notes)
Adv.dur. = 272°/282° (I/E split = 6°) (rated @ ???)
Dur. @ .050" = 214°/224° (I/E split = 10°)
Lobe lift = .2947"/.3100"
Lift @ 1.5 rr. = .442"/.465"
LSA = 112° ICL = 107° ECL = 117°

Advertised/seat events:
IO = 29° BTDC
IC = 63° ABDC
EO = 78° BBDC
EC = 24° ATDC
Total OL = 53°

.050" events:
IO = 0° ATDC
IC = 34° ABDC
EO = 49° BBDC
EC = -5° BTDC
OL @ .050" = -5°

The slight difference in the .050" numbers between the two cams is purely because the Summit lists the CL's as being 107° ICL & 117° ECL.

But 107 + 117 still = 224.

So yeah,both are 112° LSA.

Summit just lists their cam as having 5° of advance,but the odds favor that when it's degreed,it'll be exactly the same CL as the rest of those "generic" cams are at.


HTH

Bret P.

[P@blo]

Right on Bret! I always enjoy reading your posts. My 2801/980-p came in right at 107* on both the first and second try. No more regular lifters for me and will be running the hard-faced Melling JB951 from now on.