In a 1970 W-30 engine in a a car with AT, A/C and PB would the factory have put in the bigger W-30 Cam (as they did in the 4-speed)? Or, would the factory have put in the regular 442 cam?

I was told it would be the normal 442 cam because the larger cam wouldn't allow enough vacuum to build in the intake and the PB and possibly even the AT would be negatively affected.

Anyone ever heard either way????

 

402569 (328 deg.) was synchromesh trans W30 only in 1970.

 

Run,

Not sure I understand your reply. Sorry!!

 

He means, no the 328 deg W30 cam was manual trans only. Yours probably has the 308 degree cam.

 

AH? Well, now I get it. My mechanic thinks my car has the 328 cam even though it is AT, AC and PB. Of course until we open it up we are not certain...but he thinks so. If so I guess that explains the extreme rumble and shake of my engine.

 

According to Nov 72 catalog you have 400165 which was mild, 285 deg. intake/287 deg. exh. It was used on all AT 442s that year. Regular ST 442s used 406768, which had 294/296 deg. The W31 and early 66-7 W30 had 308 deg; the SM 70 had 328 deg. If you have a rough idle and low power until 3000 you probably had someone put in the big cam; if so, your power brakes won't work well. Or, something is wrong with the engine like burned vales, vacuum leak, etc.

 

Ditto what Run to Rund said.

The 1970 Engine Assembly Manual confirms that -- in 1970 -- automatic W-30s received the exact same cam as was used in all other automatic 442s, part number 400165.

The 308-degree cam mentioned was used in the W-31s. It made its only big-block appearance, if I remember correctly, in the non-AC 1968 Hurst/Olds. Too bad they didn't put it in automatic W-30s instead of the milder cam. I bet it's a good fit. [Edit: Yes, there was also a different 308-degree cam used in the '66-67 W-30s. I don't know how its openind and closing events might have differed from the 1968 and later 308 cam.]

I wonder how many guys ordered a brand new automatic W-30 in 1970 and were shocked to find it idled much smoother than their friend's manual W-30? There was absolutely nothing in the dealer and customer information which would've let them know the automatics got such a mild cam.