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Wedge
02-17-2010, 07:20 PM
Hi , I wanted to know how can i know for sure the engine i have has Poncams intalled i dont see any writtings on the cams themselves ?

Thank you .
Zacho
02-17-2010, 10:27 PM
As far as I know tomei cams do have the brand cast in...like so.
http://www.nissansilvia.com/forums/uploads/monthly_09_2009/post-16322-12543137220775_thumb.jpg

If you do suspect aftermarket cams of perhaps another brand, check to see if they have the cutouts to access the head bolts while the cams are in. Some aftermarket cams won't have this cutout (tomei poncams do have them, just like stockers)

These aftermarket cams (kelford) have no cutouts,

http://www.enjukuracing.com/images/Kelford.jpg

While tomei and OEM cams (among some others) do have them...like so

http://i2.frsimg.com/images/detailed_images/Tomei_RB26Poncams_4_10299.jpg

Better yet, show us a picture?
mcfly
02-17-2010, 10:59 PM
A sure way of figuring out what cams you have is to measure them. Measure the width and height to get base circle and lift.

There are only so many cams made for the rb that it's easy to find the manufacturer then.
Wedge
02-18-2010, 03:17 PM
I do have cut outs, I cant measure the lobes yet because im away from home for now but if i dont find out before i get back ill measure them after. Here are some pictures i dont see a Tomei stamping no where on them .

http://i39.photobucket.com/albums/e162/bashand2001/RB26%20Transplant/SDC10156.jpg
http://i39.photobucket.com/albums/e162/bashand2001/RB26%20Transplant/SDC10158.jpg
http://i39.photobucket.com/albums/e162/bashand2001/RB26%20Transplant/SDC10160.jpg
http://i39.photobucket.com/albums/e162/bashand2001/RB26%20Transplant/SDC10161.jpg
M13
02-19-2010, 02:11 AM
Those are OEM.
Wedge
02-19-2010, 02:48 PM
How can you tell ? I want to be sure since I paid for an engine that was suppose to have Tomei Poncams in them !
Zacho
02-19-2010, 09:10 PM
If you want to be sure, measure them as McFly said. If you were told you have tomei cams I would think that they all would have the brand cast in like I posted a picture of above.
charles620
02-20-2010, 04:06 AM
I sold Wedge that motor and it suppose to come with tomei poncams when I bought the car from adam@feast...

I have a set of stock cams but they don't have those markings...
Wedge
02-20-2010, 08:47 AM
I will rotate the crank 1 turn when i get home , maybe i just cant see the brand name when on TDC . Then if i cant see it ill measure them . When i took off the valve cover to have them poweder coated i thought it was odd that i couldnt see the brand name anywhere .
4jo3
02-20-2010, 04:59 PM
tomei poncams are usually reground stock cams. it is best to measure to find out what they are.
mcfly
02-21-2010, 12:29 AM
tomei poncams are usually reground stock cams. it is best to measure to find out what they are.

jun cams are typically reground stock cams too. But boy do they work stellar.
This explains the base circle reduction to get the bigger lift.

32mm vs 29 for big juns
8.4mm lift vs 11.35
M13
02-21-2010, 03:43 AM
How can you tell ? I want to be sure since I paid for an engine that was suppose to have Tomei Poncams in them !

that picture and poncams I've seen had TOMEI cast in, but it may differ from manufacturing dates/runs.

Check your base circle and lift to be sure though.
Allan74
02-22-2010, 05:16 PM
FYI. Tomei grind Cams inhouse, from blanks.....(saw the video) ;)
4jo3
02-22-2010, 08:09 PM
is that pro or pon?... i was sure poncams were regrinds and procams were ground from blank camshaft stock. now it may be the other way around ... you have me second guessing myself.... do you have a video?
mcfly
02-22-2010, 08:25 PM
is that pro or pon?... i was sure poncams were regrinds and procams were ground from blank camshaft stock. now it may be the other way around ... you have me second guessing myself.... do you have a video?

only HKS made billet cams, out of japan anyways.
Wedge
02-25-2010, 08:44 PM
Ok i measured a lobe on exhaust side and the base circle is 32,43 mm and the high of the lobe is 41,19 mm .
mcfly
02-26-2010, 12:11 AM
well a pon cam would be a close bet
cant tell if it is type a or type b by the lift.

Then again they could be any aftermarket cam with a 9.15~ mm lift.
Allan74
02-26-2010, 06:53 PM
cant tell if it is type a or type b by the lift.
If they are Tomei's, you can tell between Type A and B.....just not R and B (without them being side-by-side to compare).

R has matched 250 Duration, A has split duration 250/260, B has matched 260. All are equal lift.
mcfly
02-27-2010, 01:10 AM
yes, so you cannot determine a/b from the lift.
Skym
02-27-2010, 01:30 AM
Some reprofiled stock RB20, RB25, RB26 cam specs are mentioned here -

http://camshafts.co.nz/Nissan.aspx
jimbojones
03-10-2010, 11:00 AM
Ok i measured a lobe on exhaust side and the base circle is 32,43 mm and the high of the lobe is 41,19 mm .

Math says these are 8.76mm lift...lowest Tomei goes is 9.15 and those look nothing like my Tomei's...

Tomei stock #'s: http://www.tomei-p.co.jp/_2003web-catalogue/e090_camshaft-specs.html

Edit: base circle should be 32mm. Are your measurements EXACT?

HKS Step 1's are the only cams I can think of that come (prebuilt) as 8.7mm lift; duration 264....I cant read the last digit clearly in the photo (looks like maybe 269?). Would also have 'HKS' stamped on it and I think their lift/duration are also stamped. If it's NOT 264, then these may be a knock-off/regrind.
mcfly
03-10-2010, 11:04 AM
Jimbo is on to something, my math sucks and they can't be pon cams ;)
Wedge
03-11-2010, 10:09 PM
The measurments could be a little wrong i just used my caliper and did my best to take the measurments but it should be by much i dont want to take out the cams just to measure them but ill try to check again if my measures change . The HKS dont have the indentation in them so its starting to look like i have stockers in their !