Shadbolt cam specs

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Tyler
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Shadbolt cam specs

Post by Tyler »

well i got a shadbolt 445 cam and i forgot the cleaence for intake and exhaust
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Byron510
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Re: Shadbolt cam specs

Post by Byron510 »

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

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Rehs
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Re: Shadbolt cam specs

Post by Rehs »

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.
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rnorrish
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Re: Shadbolt cam specs

Post by rnorrish »

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
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shardik wrote: My swap will be made of solid gold and it will run on puppy farts.
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Rehs
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Re: Shadbolt cam specs

Post by Rehs »

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)
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rnorrish
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Re: Shadbolt cam specs

Post by rnorrish »

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
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shardik wrote: My swap will be made of solid gold and it will run on puppy farts.
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jason
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Re: Shadbolt cam specs

Post by jason »

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
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rnorrish
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Re: Shadbolt cam specs

Post by rnorrish »

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
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shardik wrote: My swap will be made of solid gold and it will run on puppy farts.
banzai510(hainz)
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Re: Shadbolt cam specs

Post by banzai510(hainz) »

MY Schneider specs say .006 .008 cold from the spec book.
Long as it works
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bertvorgon
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Re: Shadbolt cam specs

Post by bertvorgon »

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

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510rob
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Re: Shadbolt cam specs

Post by 510rob »

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...
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Byron510
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Re: Shadbolt cam specs

Post by Byron510 »

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!
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rnorrish
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Re: Shadbolt cam specs

Post by rnorrish »

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
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shardik wrote: My swap will be made of solid gold and it will run on puppy farts.
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jason
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Re: Shadbolt cam specs

Post by jason »

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
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Byron510
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Re: Shadbolt cam specs

Post by Byron510 »

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

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