[Fot] Mystery cam

[Bill Babcock]

I redid the numbers with the rockers removed, with the dial indicator in the cup of the centered pushrod. Measured open/close at .050. I set the intake lobe center to 108 using .070” before the maximum lift reading (.370) and then got these numbers: 
Intake opens (.050”) at 28 BTC
Closes (.050”) at 66 ABC
Exhaust opens (.050”) at 62 BBC
exhaust closes (.050”) 33 BTC

Calculated: 
61 degree overlap
274 duration intake
275 duration exhaust
106.75 lobe separation
Intake lobe center 109
exhaust LC 104.5

the calculated intake lobe center using 050” from open/close is a degree more than the measured using .070” before max lift. seems odd, but it's been a long day staring at little numbers. At least it’s starting to look something like a cam. 





> On Jun 14, 2016, at 4:19 PM, Kas Kastner <kaskastner at gmail.com> wrote:
> 
> And at  what clearance are you getting these numbers? I've a bunch of cam data I can check against and maybe assist here. Are you taking the checking clearance of about.016 or at .050?
> 
> Never be beaten by equipment.
> 
> 
> On Tue, Jun 14, 2016 at 11:12 AM, Bill Babcock <ponobill at gmail.com <mailto:ponobill at gmail.com>> wrote:
> I set it up like a Tiltech 298DX and got:
> Intake
> 45 BTC
> 71 ABC
> Exhaust
> 82 ABC
> 35 ATC
> 
> Intake duration = 296
> Exhaust duration 297
> Intake lobe center 103 ADC
> Exhaust LC 113.5 BTC
> Lobe sep 108.3
> Overlap 80
> 
> Still doesn’t look quite right.
> 
> 
> > On Jun 14, 2016, at 10:46 AM, Bill Babcock <ponobill at gmail.com <mailto:ponobill at gmail.com>> wrote:
> >
> > Searching around on the web, it kind of looks like a TilTech 298Dx, but I don’t recall buying a cam from Larry and Tony Garmey doesn’t think so either. I could just set it up as if it were, but it would be good to know.
> >
> >
> >> On Jun 14, 2016, at 10:40 AM, Bill Babcock <ponobill at gmail.com <mailto:ponobill at gmail.com>> wrote:
> >>
> >> Oh, and the lift is .372
> >>
> >>
> >>> On Jun 14, 2016, at 10:11 AM, Bill Babcock <ponobill at gmail.com <mailto:ponobill at gmail.com>> wrote:
> >>>
> >>> I’m building a new motor for Peyote from the bits of it’s previous engine. I discovered the front main bearing cap was cracked in half when I decided to freshen the motor. I’ll work on replacing the cap later—maybe get a billet one made, but in the meantime I’ve run into a minor problem. I don’t know for sure what cam I have or how it should be set.  Tony Garmey says it’s a BFE cam, but I can’t find any specs for those and can’t get ahold of Ken.
> >>>
> >>> I ballparked where I think the cam might want to be and got this for measurements:
> >>>
> >>> Reading the Intake and exhaust valve movement from the spring retainers I use 0.033” as the open/close height which is .050/1.45 which as I recall is the ratio of the stock rockers”
> >>> Intake open .033 @ 36 BTC
> >>> Intaake close .033” @ 76 ABC
> >>> Exhaust open .033” @ 76 ABC
> >>> Exhaust close .033” @ 42 ATC
> >>>
> >>> By my calculations that gives:
> >>> Intake duration 292.0 degrees
> >>> Exhaust duration 298 degrees
> >>> Intake lobe center 110.0 ATC
> >>> Exhaust lobe center 107 BTC
> >>> Overlap 78
> >>> Lobe separation angle 108.5
> >>>
> >>> Pretty sure this isn’t exactly where it needs to be. I have a vernier sprocket so I can adjust the timing precisely. My questions are:
> >>>
> >>> What cam is this?
> >>> Where should it be set?
> >>> How much advance?
> >>
> >
> 
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