Compendium of cam info

Here's the place for info on converting to a Type V motor!
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tencentlife
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Compendium of cam info

Post by tencentlife » Thu Dec 13, 2007 10:10 pm

Here's some info I collected on several camshafts that work in wbx's with hydro lifters. If anyone has other info on cams you've used in a wbx or obx that wouldn't be easy to find elsewhere, please add to this thread by posting your figures.

Sorry for the poor quality; this is just a scan of a hand-drawn chart. Hope you all can make it out and some of you find it useful.

It was all measured in a mocked up engine with a stand-in solid lifter, except for the CB 2252 which was taken from a built engine with hydro lifters and is incomplete. I took lift at the cam itself (indicaed by C"), and then lift at the valve with 1.1 and 1.25 rockers. Interesting how much changing ratios alters the opening/closing events' timing, and in ways that aren't entirely predictable.

The MV and DH OEM cams were serviceable used ones, but the figures may vary by a couple degrees and the lift could be a bit more on a new stick. The CB 2252 had 10k miles on it, the 2254 was unused.

I set up a repeatable process and did the measurements at least twice for each. The degree points could vary +/- 1 degree; I would say lift is within a couple thou.

For each cam, there is the calculated lobe center angle (LCA), the duration at 0.050" lift based on my measured lift points, degree position at 0.001" open and close, and 0.050" open and close. In the middle is maximum lift either at the cam or the valve ("LIFT @ L.C"), and the degree point where it occurs.

I wouldn't estimate myself what the advertised durations might be; I think it's particularly irrelevant where hydro-grind cams are concerned anyway. Where an advertised duration is indicated, it is CB's figure, not mine.

Enjoy the lumps!

Image
Last edited by tencentlife on Sun Jul 20, 2008 3:46 pm, edited 1 time in total.

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fastback
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Post by fastback » Fri Dec 14, 2007 6:57 pm

goody.

A couple of camsharts from CB/eagle hydraulic grinds:



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Last edited by fastback on Sat Dec 15, 2007 5:18 am, edited 1 time in total.
VW type 2 splitbus 2.1 WBX turbo
11.92@187.89Km/h.

tencentlife
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Post by tencentlife » Fri Dec 14, 2007 9:24 pm

Right on.

51MAN
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Post by 51MAN » Sat Dec 15, 2007 7:00 pm

I have some numbers, but I didnt take them.. I seem to remember that they may be "official" specs... but I am not sure...
Now I just have to remember where the file is...... :roll: :D :D

Chris.. PM'd yer...

tencentlife
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Post by tencentlife » Sun Dec 16, 2007 10:33 am

I think either actual cam cards or numbers taken by personal measurements would be most useful. Info we could glean from advertisements and such, less so. Myself, I especially want to know things like intake closing position, as that is needed to calculate dynamic CR, and the amount of overlap, etc.

I have the cam cards for the CB 2252 and 2254. I'll get those scanned and put up here as well. I think my 2254 numbers may be slightly different from fastback's for the same cam.

51MAN
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Post by 51MAN » Sun Dec 16, 2007 6:49 pm

I'll PM you the numbers (just in case they are confusing to the thread) so you can have a look at them and see if they are usefull..

tencentlife
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Post by tencentlife » Sun Dec 16, 2007 8:21 pm

Well, if YOU think they're useful, put 'em up!

51MAN
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Post by 51MAN » Sun Dec 16, 2007 8:32 pm

Well... make what you will of this...
MV and DJ cams are the same....!!! ??
DG is the 1.9 early and late versions with the same carb and not Fi... 78bhp is the spec for both even though there is a difference in cam...!!!

Looking at it, I dont understand why vw didnt use the 2.1 cam in the 1.9 too.. surly it should give better inlet charging with the "restricted" carb chokes...??

DG
Valve timing at 1mm lift.
Inlet opens. 5° BTDC (1° from 01/86)
Inlet closes. 34° ABDC( 30° from 01/86)
Exhaust opens. 38° BBDC (36° from 01/86)
Exhaust closes. 4°ATDC (8° from 01/86)

MV
Valve timing at 1mm lift.
Inlet opens. 10° BTDC
Inlet closes. 48° ABDC
Exhaust opens. 50° BBDC
Exhaust closes. 0° ATDC

DJ
Valve timing at 1mm lift.
Inlet opens. 10° BTDC
Inlet closes. 48° ABDC
Exhaust opens. 50° BBDC
Exhaust closes. 0° ATDC

mattcfish
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Re: Compendium of cam info

Post by mattcfish » Sat Nov 09, 2013 1:11 am

I need help with cam measuring lingo.
I'm trying to identify the cam in my 2.2L wasserboxer while still in the engine. The motor is on a stand, I've made a degree wheel, and have rigged up a dial indicator to an intake valve. I should add that I'm using 1.25 rockers and have subbed in a solid lifter.
When they say "at 1mm lift" does that mean 1mm after the valve begins to open? What about closing? Is that 1mm before it closes or 1mm after it starts to open again? With my ratio, 1mm lift should be a larger number, what number should that be? 1.25mm? Any clarification would be helpful, I'm not matching the MV specs very well. "Tencent's" figures are even more unobtainable.
Thanks

Ian Godfrey
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Re: Compendium of cam info

Post by Ian Godfrey » Sun Nov 10, 2013 6:12 am

normally i would measure the 1mm at an intake lifter. You could measure it at the push rod at the cylinder end if it had some kind of guide so it went straight up and down under your dial indicator. you could make a special push rod with a hollow for the tip of the gauge (even a piece of dowel could work). You should then be able to plot the cam on the intake side. Move you fixings to an exhaust valve and go plot again.

mattcfish
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Re: Compendium of cam info

Post by mattcfish » Mon Nov 11, 2013 1:08 am

After painstaking measurements over and over again using solid lifters, a dial indicator, and a degree wheel, with the engine on a stand, this is what I came up with.

My cam
Valve timing at 1mm lift
Inlet opens.13° BTDC
Inlet closes. 48° ABDC
Exhaust opens. 38° BBDC
Exhaust closes. 4° ATDC

Max lift intake=.36" to .37" with 1.1 ratio rockers
Max lift ehaust=.35" to .36" with 1.1 ratio rockers

That makes it a cross between a DG and an MV. MV intake, DG exhaust.
The intake is advanced around 3-4 degrees over stock with 3-4 degrees more duration.
The exhaust is 12-14degrees retarded with 9 degrees less duration.
Looks like something got messed up in the regrind.

The intake is close enough to an MV, with a little advance that should actually help low end.
The DG exhaust bothers me though. The engine has had lumpy idling characteristics from the beginning, despite having the entire fuel injection system and ignition replaced. Can't see how the retarded exhaust valve opening and shorter duration on a 2.2 engine could help anything. Am I wrong?

Short of replacing the cam, could putting 1.25 ratio rockers on just the exhaust help smooth the idle out by allowing the exhaust to breath better in relation to the intake?
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jackstraw
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Re: Compendium of cam info

Post by jackstraw » Tue Apr 10, 2018 6:12 pm

Bump bump bump stick. Anyone know how to get the pic back in the first post?

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ajdenette
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Re: Compendium of cam info

Post by ajdenette » Thu Apr 12, 2018 8:13 pm

Camchart.jpg
Here it is, so it will be around for a long time I attached it here but there is also an extension for Google Chrome that will make the photo's appear as they used to.
You do not have the required permissions to view the files attached to this post.
Alex

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()_)-----()_)----)_)

jackstraw
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Re: Compendium of cam info

Post by jackstraw » Thu Apr 12, 2018 9:42 pm

Awesome. Thank you.

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