| ausmini https://www.ausmini.com/forums/ |
|
| Lumpy Cam Vs Rough Running https://www.ausmini.com/forums/viewtopic.php?f=2&t=61326 |
Page 1 of 1 |
| Author: | 72clubman [ Thu Feb 25, 2010 7:48 am ] |
| Post subject: | Lumpy Cam Vs Rough Running |
Not sure if my new motor is just running rough, or if its the CAM which has a Seat duration is 292 degrees inlet, 295 exhaust i find at idle the car seems to shake a bit, tried idle speeds from 900rpm to about 1300rpm how do you tell the difference between a sporty cam and rough engine running? |
|
| Author: | drmini in aust [ Thu Feb 25, 2010 7:55 am ] |
| Post subject: | |
With that much duration it's more race cam than sporty. Try increasing the advance, if this improves low speed running and torque, mod the advance curve some more by reducing the camplate advance. This way you can have the same total advance but more at idle. Mine has a 9° dizzy plate, idles at around 20° advance, 38° maximum. (Note it has bathtub chambers, so needs lots of advance). |
|
| Author: | 72clubman [ Thu Feb 25, 2010 8:26 am ] |
| Post subject: | |
my dizzy was modified by graham r i notice full advance comes on by about 3000rpm sits around 25-28 deg total advance and 10 deg @ 1000rpm so the car drives ok, but just vibrates heaps while idling so it would most likely be the cam then? do you reckon penrite HPR 40 is too think oil its a 25-70 i get good oil pressure? |
|
| Author: | drmini in aust [ Thu Feb 25, 2010 8:37 am ] |
| Post subject: | |
I used to use HPR 40 in my worn 1310. Then I rebuilt it and used HPR30. I think KMart's KMX 20W/50 is a better Mini oil, and much cheaper. I reckon yes it's the cam, but you could improve it lots with some more idle and low speed advance. Advance it 5° for a test and see if the bottom end clears up (don't rev it high). If so, get Graham to take another 2 or 3° out of the plate. I reckon you want 15° static advance with that cam. |
|
| Author: | Super-mini [ Thu Feb 25, 2010 3:50 pm ] |
| Post subject: | |
if GR did it, best to take it back to GR? i reckon 25/70 is too thick for a fresh motor, you might get good pressure but flow would be reduced and it would sap a couple HP |
|
| Page 1 of 1 | All times are UTC + 10 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|