Shadbolt cam specs

New posts disabled. Archived technical discussion about the Datsun PL510
Tyler
Posts: 94
Joined: 14 Feb 2007 17:15
Location: Vancouver
Contact:

Shadbolt cam specs

Postby Tyler » 11 May 2008 18:56

well i got a shadbolt 445 cam and i forgot the cleaence for intake and exhaust

User avatar
Byron510
Moderator
Posts: 11676
Joined: 01 Jul 2003 23:06
Location: Maple Ridge, BC

Re: Shadbolt cam specs

Postby Byron510 » 11 May 2008 20:29

For street use, stick to the stock specs of 0.008" In/0.010" Ex. (hot settings always)

Byron
Love people and use things,
because the opposite never works.

User avatar
Rehs
Posts: 524
Joined: 20 Mar 2006 21:54
Location: Richmond, B.C.

Re: Shadbolt cam specs

Postby Rehs » 12 May 2008 10:47

I thought the stock clearance was:
Int. 0.008" Exh. 0.010" Cold
Int. 0.010" Exh. 0.012" Hot

According to the specs I got from Shadbolt, the running clearance(Hot) was:
Int. 0.008" Exh. 0.012"

I ran these specs. with my 445 and it quieted the valve train down quite a bit from running it stock. Just remember to let it warm up on really cold days or you'll get the occasional slight intake back fire/pop.

User avatar
rnorrish
Moderator
Posts: 4021
Joined: 23 Jun 2003 12:49
Location: BC : CANADA
Contact:

Re: Shadbolt cam specs

Postby rnorrish » 12 May 2008 23:03

Andrew, you have the HOT and COLD backwards. The clearance gets smaller as things heat up...
richard norrish
'68 'goon resto / '71 ice racer / '72 'goon project / '70 4-door rust pile / '67 520 project
----------------------------------------------------------------------
shardik wrote:My swap will be made of solid gold and it will run on puppy farts.

User avatar
Rehs
Posts: 524
Joined: 20 Mar 2006 21:54
Location: Richmond, B.C.

Re: Shadbolt cam specs

Postby Rehs » 13 May 2008 00:09

rnorrish wrote:Andrew, you have the HOT and COLD backwards. The clearance gets smaller as things heat up...


Ok, just to be sure, I went and checked the Haynes Manual. Umm... Rich, Is it backwards day out there in Chilli Whack? Here's what Haynes has to say(Including the periods!).

Valve Clearance (warm):
Inlet ... ... ... ... ... ... ... 0.0098 in (0.25 mm)
Exhaust ... ... ... ... ... ... ... 0.0118 in (0.30 mm)
Valve Clearance (cold):
Inlet ... ... ... ... ... ... ... 0.0079 in (0.20 mm)
Exhaust ... ... ... ... ... ... ... 0.0098 in (0.25 mm)

User avatar
rnorrish
Moderator
Posts: 4021
Joined: 23 Jun 2003 12:49
Location: BC : CANADA
Contact:

Re: Shadbolt cam specs

Postby rnorrish » 13 May 2008 17:36

Then Haynes has is backwards...

as everything gets hot, the clearances close up.
that why it's better to do it hot, as you are then setting it for operating specs.
set them cold, and too small, they will heat up and "bind".
this actually just keeps the valve open for the whole turn of the cam. bye bye compression.

i should check those manuals I bought... hate to stuff my foot in my mouth.... but I'm at work.
so, "SUBMIT".
richard norrish
'68 'goon resto / '71 ice racer / '72 'goon project / '70 4-door rust pile / '67 520 project
----------------------------------------------------------------------
shardik wrote:My swap will be made of solid gold and it will run on puppy farts.

User avatar
jason
Supporter
Posts: 4960
Joined: 13 Sep 2004 18:00
Location: Vancouver, British Columbia, Canada

Re: Shadbolt cam specs

Postby jason » 13 May 2008 18:33

I'll save you the trouble Rich, the Nissan Factory Manual for 1973 from that box of manuals we got states:

cold Intake .20mm
exhaust .25mm

hot intake .25mm
exhaust .30mm

Of some interest, that's also for the L18 in the FACTORY MANUAL. I guess that means that Nissan did put L18's into the 1973 510's then as their manual includes it....
Jason

User avatar
rnorrish
Moderator
Posts: 4021
Joined: 23 Jun 2003 12:49
Location: BC : CANADA
Contact:

Re: Shadbolt cam specs

Postby rnorrish » 13 May 2008 22:55

oh man. this doesn't make any sense.

maybe that's why my motors (Datsun ones at least, not VWs) are so quiet - I always run .008 & .010 hot.
richard norrish
'68 'goon resto / '71 ice racer / '72 'goon project / '70 4-door rust pile / '67 520 project
----------------------------------------------------------------------
shardik wrote:My swap will be made of solid gold and it will run on puppy farts.

User avatar
banzai510(hainz)
Posts: 3685
Joined: 24 Mar 2004 07:01

Re: Shadbolt cam specs

Postby banzai510(hainz) » 14 May 2008 06:14

MY Schneider specs say .006 .008 cold from the spec book.
Long as it works

User avatar
bertvorgon
Supporter
Posts: 9966
Joined: 04 Aug 2003 20:45
Location: White Rock, B.C. Canada

Re: Shadbolt cam specs

Postby bertvorgon » 14 May 2008 06:26

Any of my performance cams have always been .008" intake and .010" exhaust HOT, which were either Shadbolt Cams, or my latter ones from Colt Cams.. I get the motor to 180-190F, shut it off, and do the intakes first, then the exhaust. Stock I always used .010" intake and .012" exhaust hot.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

1973 2Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1968 Vintage 3HP Mini Bike
1971 Vintage 13' BOLER trailer

510rob
Moderator
Posts: 4559
Joined: 09 Oct 2003 23:37
Location: Vancouver, BC
Contact:

Re: Shadbolt cam specs

Postby 510rob » 14 May 2008 15:28

Racer Brown made brief mention of the cold lash versus hot lash subject in his famously detailed camshaft article in the How To Modify Nissan Engines and Chassis (edition one has it, and I think edition two has it as well). It's probably about 2 or 3 lines out of 42 pages, from what I remember...

User avatar
Byron510
Moderator
Posts: 11676
Joined: 01 Jul 2003 23:06
Location: Maple Ridge, BC

Re: Shadbolt cam specs

Postby Byron510 » 14 May 2008 22:25

It took me a while to research this...
Originally I though Rob had referenced the How to Modify your Nissan/Datsun OHC engine. The lash info specifically was not there, but I needed to skim the book anyways…

The comment that Rob referred to is out of the "How to Hotrod and Race your Datsun 510,610 240Z" - The Bible if you will. And this section on camshafts is one of the reasons why it's called the bible. There was a newer edition of this book, but this cam shaft section hit the cutting floor, and I have no idea why. This is a very in depth chapter and relevant to all camshaft design and application..

Anyways, here is the page about lash. Don't worry; I wasn't the one who marked this copy. In fact there’s pen all over this copy. I do have a virgin copy of this book, in a dehumidified/fireproof room... this is my working/reference copy :D

Byron

PS thanks for making me look this up Rob, I needed a refresher!
Attachments
Racer Brown...0002 (Large).jpg
Love people and use things,
because the opposite never works.

User avatar
rnorrish
Moderator
Posts: 4021
Joined: 23 Jun 2003 12:49
Location: BC : CANADA
Contact:

Re: Shadbolt cam specs

Postby rnorrish » 14 May 2008 23:21

that reminds me, who measures it at the cam? and who measures it at the rocker tip?
this article made me think of all the extra lift i get, doing it at the tip, but using at-the-cam specs. :D
richard norrish
'68 'goon resto / '71 ice racer / '72 'goon project / '70 4-door rust pile / '67 520 project
----------------------------------------------------------------------
shardik wrote:My swap will be made of solid gold and it will run on puppy farts.

User avatar
jason
Supporter
Posts: 4960
Joined: 13 Sep 2004 18:00
Location: Vancouver, British Columbia, Canada

Re: Shadbolt cam specs

Postby jason » 03 Aug 2011 20:02

I flipping got caught with this again, I just set the valve clearance on my stock cam at .010 inlet, .012 exhaust! Bloody hell, guess I have to do it again !
Jason

User avatar
Byron510
Moderator
Posts: 11676
Joined: 01 Jul 2003 23:06
Location: Maple Ridge, BC

Re: Shadbolt cam specs

Postby Byron510 » 04 Aug 2011 22:04

Jason - it'll work fine for your stock motor - no worries. You're going to check it a few months anyways - right? :wink:

Byron
Love people and use things,
because the opposite never works.


Return to “Technical - Archive”



Who is online

Users browsing this forum: Google [Bot] and 3 guests