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Camshaft ID
https://www.ausmini.com/forums/viewtopic.php?f=5&t=502		 Page 1 of 2
Author:  Christoph [ Mon May 03, 2004 10:12 pm ]
Post subject:  Camshaft ID
I have just started stripping down the 998 engine that came on the parts car (the one with the 12G295). So far i have found a duplex timing set up (just what i wanted) and a camshaft with '620' stamped on the end. There are no other numbers stamped on it anywhere, or any grooves/rings/bands anywhere either.
Does anyone know if the '620' has anything to do with the profile and if so what profile it is?
The camshaft is pin drive and has 3/8" lobes.
BTW the camshaft profile does look similar to the 260ish degree cam in my car currently, compared with a stock 1098 cam (not that its easy to see the difference though).

cheers.
Author:  drmini in aust [ Mon May 03, 2004 10:33 pm ]
Post subject: 
Could be a Camtech. They grind cams for Karcraft, too.

My old Camtech list shows 616, 631, 619 (VP3), 630, 625.

A 620 is listed for an MGB, but profile was also used for A series. Timing is 20-60/56-16. :wink:
Author:  Christoph [ Mon May 03, 2004 11:10 pm ]
Post subject: 
Thanks, so i guess that means the cam would have a duration of 260/252 probably not better than what ive currently got, but anto might be interested in it.
Author:  Anto [ Tue May 04, 2004 10:29 am ]
Post subject: 
Yes he would. Especially as Kevin has pointed out how easy it is to do a cam change!
I should have put money on it being duplex, shouldn't I??
Well I'm off to Warren's now to get some valve stem seals.

Cheers,
Anto.
Author:  drmini in aust [ Tue May 04, 2004 10:33 pm ]
Post subject: 
Anto, whatever cam you fit, buy a NEW set of lifters... otherwise it may have a short life.. :cry:

<edit> I'd say it would go harder with a Graham Russell cam. 1098s need around a 270 duration cam to wake 'em up! :wink:
Author:  Christoph [ Tue May 04, 2004 11:22 pm ]
Post subject: 
Where do these Graham Russel cams come from/where can you get them? We are from canberra and no nothing about them... apart from the high praise of Dr mini in aus gives them.
Author:  drmini in aust [ Wed May 05, 2004 6:58 am ]
Post subject: 
Russell Engineering,
113A North Rocks Rd,
North Rocks, (Sydney).

ph (02) 9630 2195

<edit> They build some (most?) of the fastest Mini race motors in Australia- used to advertise in Mini Magic magazines.... 8)
Author:  Anto [ Wed May 05, 2004 5:24 pm ]
Post subject: 
For comparisons sake I think the duration of the cam I'm currently running is something like 230/252 according to Hammill. The Camtech would also have more overlap on exhaust (don't know if that is a good thing or not, but anyway).

Yeah I can remember the Russell Engineering ads. Did he race a white Cooper S?

Anto.
Author:  Christoph [ Wed May 05, 2004 7:19 pm ]
Post subject: 
overlap is good as long as you have a good exhaust system, the exhaust's extracting effect draws in more fresh charge into the combustion chamber if the overlap is bigger. So yes, more overlap is a good thing, only downside is at low revs it causes the rough running associated with most high duration camshafts. However i dont think the greater overlap would cause rough running in this case. please correct me if im wrong.

cheers
Author:  drmini in aust [ Wed May 05, 2004 7:29 pm ]
Post subject: 
With an RE-13 cam, my 1310 will choof around at less than 2000 revs on light throttle, take full throttle (45 Dellorto) from 2700 with 1.5 rockers, and it don't let up until 8000.. 8)

Duration is 277 intake, 286 exhaust.. it has more power and torque than the Camtech VP3 I had before.

My son's 1132cc Clubbie has a Camtech 631 in it- 272* duration. It pulls well even with just an HS4 carb, rockers are stock 998.
Author:  Anto [ Wed May 05, 2004 7:30 pm ]
Post subject: 
Well it is only 40* of overlap as opposed to 30*. And anyway, I like that 'cammy' sort of idle - that way people know your engine is tough! (until, in my case, you dump the clutch and prove them wrong).
This sounds like one of those 'wouldn't an LCB and Perry exhaust system suit your car' kind of spiels.... :) :)
Author:  drmini in aust [ Wed May 05, 2004 9:51 pm ]
Post subject: 
Yes, a Perry LCB runs nice on a 1098. :wink:

I've found SU's make an engine sound cammier at idle than a Weber or Dellorto does with the same cam. Strange.. 8)
Author:  Anto [ Thu May 06, 2004 8:59 am ]
Post subject: 
Mine already sound a bit rough at idle, but that could be the slightly worn throttle spindle perhaps!
Author:  Christoph [ Thu May 06, 2004 5:09 pm ]
Post subject: 
What duration cam could the 1100cc take with the 12g295 and still be good for around town driving aswell. My current setup has bags of torque but doesnt seem to have much top end power (well i guess it is a stroker, but it feels a little restricted above 5,000rpm). I was very surprised at how well your 1310 ran at low rpm.
Author:  drmini in aust [ Thu May 06, 2004 7:52 pm ]
Post subject: 
I used to run a bored 1100 with a 544 cam (288* duration...) and it flew..
It's a bit hairy for a 1098 crank- they do bust if you rev much past 7000 ... ask me how I know.. :cry:

Cams around 270* work good- Camtech 631, Kent 286, Tighe 104, etc.
A 1098 can stand more cam duration & overlap than a 998 due to its extra stroke

Graham Russell puts an RE13 grind in just about everything and it works. James Be's 998 turbo 998 has these same shape cam lobes but on a wider LCA- it's got around 15psi at 7000 now.. :wink:
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