CRG Discussion Forum

Camaro Research Group Discussion => Originality => Topic started by: Dr L-88 on January 21, 2015, 03:04:28 PM

Title: 140 cam.........................how much vacuum ?
Post by: Dr L-88 on January 21, 2015, 03:04:28 PM: I'm sure some of you have run the 302 Z/28 140 cam in your small blocks at one time or another. I am curious as to how much vacuum this cam will generate.

Here are the cam specs:

First Design Off-Road cam, P/N 3927140
Casting #3927141
Intake 257 duration @ .050" (333 advertised)
Exh. 269 duration @ .050" (346 advertised)
Lift: .493" intake, .512" exhaust
Intake Max lift @ 108 deg. ATDC
Exhaust Max lift @ 116 deg. BTDC

As always, thanks in advance for your input.
Rex
Title: Re: 140 cam.........................how much vacuum ?
Post by: 69z28302 on January 22, 2015, 03:00:00 AM: Rex you didn't buy a Camaro did you?
Mike
Title: Re: 140 cam.........................how much vacuum ?
Post by: Dr L-88 on January 22, 2015, 03:24:31 AM: No.........................still stuck with this old Corvette ;D
Title: Re: 140 cam.........................how much vacuum ?
Post by: Jon Mello on January 22, 2015, 05:04:51 AM: Rex, I ran the 140 cam in my old '69 Z for three years and never had a gauge on it to measure the actual vacuum, but there was never an issue with the operation of the power disc brakes, if that is the area of your concern.
Title: Re: 140 cam.........................how much vacuum ?
Post by: BillOhio on January 23, 2015, 01:25:51 AM: My car still has one. Never noticed anything funny on my brakes. If you want to hear one, there's some videos on you tube.
Title: Re: 140 cam.........................how much vacuum ?
Post by: Oaklyss on January 23, 2015, 02:46:45 PM: 6-7"hg. Use an adjustable vacuum advance unit. Change power valve(s) to 3.5 and add power valve blow-out protection as engine will pop sometiimes when cold. And nothing sounds like these cams!
Title: Re: 140 cam.........................how much vacuum ?
Post by: JohnZ on January 23, 2015, 05:31:13 PM: The stock Z/28 cam (-346) will pull about 9"-10" Hg. at 900-1000 rpm; I'd expect the "140" off-road second design cam to pull about 2" less.