OBX256deg x 9mm cams,sort of a review,sort of a question

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noobee
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OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Mon Jul 30, 2012 2:30 pm

any input appreciated.
I was thinking of getting some regrinds but my son has been using an OBX lsd diff center in his 13b turbo for a few hillclimbs,been happy with it so far.So I thought I'd give a set of their el cheapo cams a go.$263 +$70 postage from california.They turned up in 7 days,upon unboxing they appeared to be very well machined all over,surface finish good, no chatter anywhere,nice radii,journal sizes all mic'ed exactly the same .they then went on the shelf with a lot of other stuff for 6 months.

two months or so ago I put them in without changeing anything else,exhaust cam went in no problem,took about an hour after opening bonnet.Inlet cam also in and pulley on without losing timing in 30 mins(including a cup of tea).However when doing up pulley bolt,it seized a little at about 15 mm in.I had one hand tap this size at home so tapped it in situ...tap was promptly buggered in about 1.5 turns,its a 30 mm hole.Soooo.. they forgot to put protective paste in thread when they were heat treated.
I wanted to drive the car so back in with the stock inlet cam,again without losing timing.Drove it about 600 k's over the next few weeks.definitely a change for the better in upper rev range,only a little lumpier at idle,happy so far.didnt actually expect much from just this as engine is otherwise stock and still got stock exhaust manifold.I was a little worried about the hardness of the cam but there are no wear marks on the lifter or on the cam.

I wasnt at work so I bought a triple set of hand taps locally ($32 for suttons plug,intermediate,taper) and tried tapping further starting with the intermediate...buggered that too in another turn.I machine some moderately hard materials at work and this was scary listening and watching the tap flex while winding back out.I waited till I was back at work and grabbed a handfull of machine taps(plug only but a little stronger than hand taps and with an expensive coating on them) with a and a .1 oversize drill as I suspected the hole was also a little tight.I drilled it out in my baby lathe at home(just fitted).again scary hard noises coming from this.Finally got it tapped after this,but still ruined another (machine) tap.
also found CAS slot was .04 undersize,again very hard.had to use a diamond file from work for this.

I was rained in two weeks ago so I decided to put the inlet cam in and start on more of the stuff on the shelf,timing belt,waterpump,crank seal,adjustable pulleys.(you were right Dann,sort of.I finally remembered I got them from here
viewtopic.php?f=44&t=47296&start=15
,lol)
I first put it in again without changing anything else,but when I started the engine it had a very cranky idle,I put a timing light on the ignition....waaay out.so time to pull the covers off and do things properly.
After fitting most things and deleting aircon I was still rained in and still waiting on a new crank bolt(turns out It would have been quicker to get them from the UK than from 5km away).so time to find out what these cheap cams really are.
IMG019.jpg
IMG021.jpg
IMG023.jpg
IMG024.jpg
CAMTIMING-OBX256--1.xls

So what do I really have,what do they compare to?
I'm mainly only experienced looking at Ducati desmo cams,and that more than 20 years ago(before kids,lol)so I dont know whats normal for these engines.
sun is shining,i've got 4 days off work,yard is almost dry enough to get car out of shed.if new crank bolt doesnt turn up shortly,i'll be just throwing the old one in and start driving.
Mick
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noobee
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Mon Jul 30, 2012 2:39 pm

could only post 5 attachments.
IMG026.jpg

lost my phone with all my photos on it.so heres a stock cam in my baby lathe.just fits!
IMG040.jpg
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Apu
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby Apu » Mon Jul 30, 2012 2:44 pm

Sweet jesus! Do you realise that it's just on a year that you bought those cam gears off me Mick?

This is well before I became the distributor for Works Engineering and I was just buying stuff for myself. It was intended for my car but didn't realise that damned VVT would mean no cams / adjustable cam gears for me!

noobee
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Mon Jul 30, 2012 2:53 pm

yep,I'm a slow worker nowadays.I often buy stuff just in case I might need em later.At show and tell at Mt Sugarloaf a few months ago Dann said he could have got them for me at a decent price,lol.I thought then I'd got em off ebay.
Mick

Apu
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby Apu » Mon Jul 30, 2012 2:58 pm

You got them at a really good price!

noobee
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Mon Jul 30, 2012 3:07 pm

too right!thats the upside.
thats why I bought them when I didnt need them.downside is,I've got a really messy shed with stuff I dont need (yet!)
Mick

project.r.racing
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby project.r.racing » Mon Jul 30, 2012 3:33 pm

noobee wrote:yep,I'm a slow worker nowadays.I often buy stuff just in case I might need em later.
I also do this, It drive the missus up the wall. I also have some Toda 256dx9mm cams and cam gears been sitting on a shelf in the garage for 6 months.

noobee
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Mon Jul 30, 2012 4:35 pm

get any data on lift profile with them?
thats the sorta thing i'm after.so I know if i should be leaving them right where they are or not.
only data I got with these was"256degree X 9mm"
(I really didnt expect anything more for the money)
I'm

sailaholic
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby sailaholic » Mon Jul 30, 2012 4:47 pm

Google tighe cams. They have a list of profiles for these motors you can compare to.

Sent from my GT-I9100 using Tapatalk 2

project.r.racing
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby project.r.racing » Mon Jul 30, 2012 4:48 pm

Mine is a BP-05 engine with solid lifters, so completely different to you B6-ZE. So profiles will be different.

noobee
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby noobee » Wed Apr 02, 2014 4:17 pm

a couple of extra pics for philm,
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PhilM
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Re: OBX256deg x 9mm cams,sort of a review,sort of a question

Postby PhilM » Thu Apr 03, 2014 11:14 am

Thanks Noobee
Good garage engineering.
I will see what I can make up to fit my dial gauge so I can work out my cams. I have not got my car back from the painters - maybe tomorrow. I/ Dann also have to work out why the Megasquirt wont hold a tune in its flash memory.
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