seems nobody knows for sure what the 67 442 4-speed cam specs are at @.050. best i can guess is 206@ .050. my question is what is the LSA for sure. thanks Joe.

 

This may help, ..

 

no just gives advertise duration. but thanks for your quick replay.

 

That's the same grind my 4 spd 70 350 rallye is supposed to have. If the GM rated 286 is the same way Pontiac rated well knowing the common Pont 068cam listed at 288/302 the 288 is known to be 212 @ 050 so my guesstimate is 210 or so IMO on the Olds 286

 

Here is the formula, now you can calculate it off the previous chart I sent you.

 

Th

is is off an old post, shows it at 114.

 

ok so 114 Lsa for sure. w-30 cam 328 - 245 so thats -84. 286-84 = 202@.050 right ? or 245 is 75% of 328, so 75% of 286 is 214@.050. whats the right way lol

 

You cannot determine the 0.050" duration without either knowing the exact shape of the lobe or checking with a dial indicator. The aggressiveness of the ramps on the lobe will change the 0.050" duration numbers. For that matter, the diameter of the lifter will change the 0.050" numbers.

 

does the 114 LSA work good with the 400 ci ?. and not knowing the duration @.050 how to you go one cam bigger in size ?

 

It will give a decent wide power band with strong vacuum good idle for power brakes and AC friendly smooth idle should pull past 5000-5500 making power at WOT

 

Valve events at 0.050" for 393859:
Intake open/close = -2°/44°
Exhaust/open close = 46°/-4°
Overlap = -6°
Duration I/E = 222°/222°
Lobe centers = 114°
Intake CL = 113°
Exhaust CL = -115°

I used this cam in a 350 Vista Cruiser and it was as Gearman described it.

 

I suggest stop thinking of it as "one bigger" or "one smaller" and just look at the specs to determine what will give you the operation you desire.

 

it is smooth at idle, had it up to 5400-5500 pulled nice. does not really turn on till 2800 rpms .

 

found the opening and closing specs. 1967 4-speed cam is on a 114 LSA, the automatic cam is on a 111.5 LSA and the w-30 cam is a 113 LSA. now if i could get the duration at .050. a good guess would be 212* @ .050 for the 4-speed cam

 

The 050 was shared in this post and elsewhere here. My initial guess of 210-212 was low it apparently is 216/217 ish on the Super Cars Unlimited one but another has come in at 222/222 but considering it has the .472 lift of all the larger ones those #s sound right

 

so what is it ? lol

 

The Spring, 1970 Supertuning booklet from Olds confirmed these specs for the "1970 310hp Sync. Trans":
P/N: 393859
IO: 30° BTDC
IC: 76° ABDC
EO: 78° BBDC
EC: 28° ATDC
Intake CL: 110°ATDC
Exhaust CL: 118° BTDC
Lobe Separation 114°
Advertised Duration 288°/286°
Overlap: 58°
Valve lift: 0.472/0.472"

Other articles have shown this information on the 393859:
Duration at 0.050": 221°/221°

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But if you buy a new one it is apparently this , so it appears the new ones are wrong and on a 112 lsa and a bit less dur and lift altered too.. probably good I bought a NOS Wolverine Blue Racer W31 cam for my Rallye the other day anyway.

 

whats the specs on your w-31 cam ?

 

same as oem advertised as 308/308 by GM but 232/232 @ 050 and on a 114 lsa same .474 .474 lift. my car as manual brakes manual steering heater only w 3.91 gear 4 spd and did big valves and head and intake porting so with headers it will appreciate more than the 70 QB code 350 4 spd cam (400 442 4spd cam) in my Rallye 350 F85

 

The specs you asked for are in Post 11.

 

where did you find them specs ?

 

I got those when I was building a 350 in 1983. I knew a racer, a great parts man at one of the large Olds dealers in Minneapolis. The specs, and others, came from a factory document that he let me hand-copy.

 

nice thanks