Topic: Measured(not advertised) specs on RC327 cam?

[gschuld]

Does anyone have the measured in motor cam specs on the RC or Dynoman 327 cam?

I’ve got 4 RC catalogs from different years and the specs don’t match up consistently between them.

Intake open/close
Exhaust open/close
Lobe centers
Lift

Thx

George
George

[NitroHunter]

Not exactly what you're looking for, but I once measured an RC 315 in two radically different heads. Zero lash, readings taken off the retainer. One head completely stock, the other was extensively modified. Seat depth and valve length had effectively altered the rocker ratio drastically, from the readings you'd never know it was the same cam. 

[livefast_dieold]

Does anyone have the measured in motor cam specs on the RC or Dynoman 327 cam?

I’ve got 4 RC catalogs from different years and the specs don’t match up consistently between them.

Intake open/close
Exhaust open/close
Lobe centers
Lift

Thx

George
George

Hi George, did you get my message on the 315 right? Check at what valve lash they were measured, It's my understanding they have been varied over the years.
Are you going to use the 327 on a 750cc engine? Curiouson how it performs on a 750, as dynoman is advertising it for big bore engines

[gschuld]

Odd on the different numbers....

No, I didn’t see the message on the 315 cam.

I have the parts of a vintage road race engine that has a custom profile that appears to be identical to my RC327 cams.  I made an aluminum pattern of the lobe shape (2 actually) and they appear to match perfectly, the lobe centers measure the same.  Lift is the same.  For some reason it appears to be a 327 cam, but rotated 3 degrees advanced at the cam gear.

I’ve seen and read about several people using the 315 cam in a 762cc road race engine, but I don’t recall seeing a score of the 327 cam being used in one.  Longer duration, higher rpm compared to the 315 with a very similar lobe profile and same lift.

I’m curious as to how it would work.  If someone were to try to raise the powerband rpm range over the 315 cam, it would seem a reasonable choice?

George

[754]

I bet the 315 with high compression at stock bore would surprise you.  Just a hunch

[gschuld]

Frank,

Ricardo runs the 315 on his road racer and seems pleased with it.

George

[PeWe]

Frank,

Ricardo runs the 315 on his road racer and seems pleased with it.

George

I think he runs valve lash of 0.25mm that match his pistons/ chambers. I had a thread about DP315 and different lash. My 1005cc engine did not like smaller lash causing more overlap and less compression. I measured compression for various lashes.
But I went for not that high compression due to longer street use. Thicker versions of RCS base and MLS head gaskets.
RC295 profile work much better in my engine for street, 2000 - 8500 rpm
Cam holders condition is something I have measured too. Higher lift and more duration on a specific cam.  Maybe a lift of 0.03 mm more on a lower mile set than my old.

My old K2 I only found as a frame  had 970 MTC pistons + RC327 cam + F2 valves In as well as Ex (ex machined to 29 mm) back in the 80"s, street as well as on the strip.

I wonder how the valve train ratio were.