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MG MGB Technical - Swiftune camshaft

Has anybody got data on a Swiftune SW5 camshaft please?


Thanks

Colin
Colin Parkinson

Colin,
have you checked out the Swiftune website?,
the only guy I know of who knows about Swiftune A-Series cams is Hap Waldrop of Acme Speedshop in the USA.
I presume you are asking on the A-Series forums because I can't find anything about them making cams for a B-Series motor.
Colyn
Colyn Firth

Hi Colin-
Found this if it helps--
Most people seem to run them as a street cam peeking out at around 5500rpm in Mini's
If it's going in a B series engine it's going to be fairly docile, not much better if any than a MGB cam, certainly won't be powering up to the red line
A stump puller in a B series I would think

The specs I found, these are at a Checking clearance of .016" at the lobe, which I imagine would be running clearance plus ramp height @ the lobe so actual timing - the bottom figure quoted of .036" lift on overlap is inlet lobe lift measured at tdc----not sure if this is actual or if the .016"checking clearance has to be added to it
----------------------------------
Checking height: 0.016" @ lobe

Timing: (Intake): 16/48 (Exhaust): 52/12

Nominal lobe lift: (Intake): 0.281" (Exhaust): 0.281"

Duration (Intake): 244 (Exhaust): 244

Lobe centre angle (Intake): 106 (Exhaust): 110

Lobe separation angle: 108

Lift on overlap: 0.036"
William Revit

Colyn, no it is a cam for an MGB, not A series.

Swiftune web site tells me nothing about MGB, and they are very busy building engines for Goodwood Revival.

I had dropped on this cam and am building a nice road engine. Thought it might be OK as I believe it is 'an ultimate road cam'!!


William, where did you get those figures from? Are they Mini or MGB? From that info you are indeed correct, it is not much better than standard, certainly not Ultimate Road!!

Colin
Colin Parkinson

Mini specs Colin, but I would expect SW5 to be SW5
I have heard that the SW5 punches above it's weight torque wise in a A series compared to other cams of similar spec but for a larger B series engine I feel it could be a bit tame
Just depends on what you plan to do with it-
Just to compare I have just fitted a cam with very similar specs to a SW6 in a friends 1800 MGA road car It goes like a train right through from 1500 rpm to 6000 but has a bit of a choppy idle--If the car you are doing is a basic road goer then the SW5 might be the business---Swifttune would have tested it I would think and be able to give you advice--

I found the specs here----just scroll down through them

https://www.tapatalk.com/groups/miniclassic/list-of-cams-and-timing-figures-t5261.html

cheers
willy
William Revit

Colin,
I really would check its for a B, I live just down the road from Swiftune and afaik they don't do anything for a b series.
David Brenchley

David, yep it is for a B!!! Bigger than a Mini one!

In a Swiftune box. They do not do a cam for a B series any more. This is a litte used one.

Colin
Colin Parkinson

Thanks for the link Willy, useful.
Colin be wary of A series cam specs in Bs they are much milder.
Take the Cooper 998 cam 2-6500 rpm C-AEG567 0.250 cam lift 0.318 valve lift 16/56/51/21 timing 252 degrees 0.015 clearance. This is the same as the Std MGB cam which is really mild in the B. The same as the Healey BJ8 cam. A favourite cam for BLMC it would seem.

We tend to run Piper HR270 at 9.75:1 for road use and for track day fun the Piper HR285 at 10.25:1 ( if less than 10.25 then the cam is flatter than the 270 below 5000 and only makes slightly more than the 270 above that!)
Peter Burgess Tuning

Peter, Colin
Had a chat to my camgrinder mate and he agrees that it will be fairly tame in an 1800 'but' pointed out that it does have a little more lift than a std MGB cam and that Swifttune cams are fairly fat in the lobe design and that although the specs look low the cam actually opens the valves quite quickly compared to most others and the cam ,although it should idle very smooth will actually operate more like a cam with a few more degrees duration---A bit like a basic cam with higher ratio rockers

If the engine is basically std and is going to be driven like a std car then it could be just fine

You have to be really honest with yourself as to how many revs you are planning to use and the purpouse of the car

It's got me in--I've been searching everwhere for mention of this cam in an 1800 and actually found something
Second one down in the list, the cam is angrier but SW5 gets a mention in the brief
It may well be something magic--don't know
Be warey though as they are rating a std MGB cam higher at their stage 3
I still think it's going to be a lesser cam than an MGB cam unless there's some magic in there

Maybe if you emailed these NZ guys they could give you a guide seeing as they mention it

http://www.aucklandcams.co.nz/cam_listings.php?title=MGB%201800
William Revit

The profile 14 looks to be what we have as a standard B grind from Piper. I think it is the 567 Leyland cam.
Cam grinders seem to have lost the OE spec for Bs. I have a brand new OE standard cam but do not want to send it in and lose the cam by mistake! I sent a 770 OE cam in for measurements and the OE ST tubular box was thrown away by mistake, I got the cam back but saddened to lose the OE packaging .
Peter Burgess Tuning

I'll ask my bloke if he has the std MGB specs
I know he has profiles for most BMC/Leyland cams
William Revit

Thanks for your comments. It seems the profile of the SW5 does nothing for a B. The engine is +.060 pistons, lightened and balanced and for fast road use only.

Peter, I think I will follow your advice on this one and go for a 270, and probably get Piper to reprofile the SW5.

Colin
Colin Parkinson

Hi Colin, it is always a good idea to buy a new cam as repro ones do not, as a rule, get re-hardened so life is somewhat curtailed.
Peter Burgess Tuning

Colin
Have a look at the Newman PH1 Cam specs,
It is their fast road cam and on my 1950cc 5-brg engine it produces 140 bhp with 150 ft-lb torque.
It it awesome.
(Newman make the Moss supercharger cam)

Cheers
Colyn
Colyn Firth

Thanks Peter, I dont think any reprofiled cam is re- hardened, and not all new ones are hard enough, as i have found out!!!

I cannot remember the figures we got, but soft as pig sh!t!!

Colin
Colin Parkinson

Colin
Now that we know it's for fast road use, I doubt the SW5 will be any good to you
It may have been borderline ok for a std replacement cam for a stock MGB
but if you're wanting fast road it isn't the cam you want, specially as well being .060"up

The SW5 appears to be a decent cam for road use in a A series but your engine is nearly double the capacity and will need more camshaft to go with the increase in size

There has been a lot of people use a cam here called a 240 which is a bit strange really as it has 280 duration 30/70-71/29 with good results, a nice driveable cam
As mentioned early on I recently fitted up a cam similar to a SW6 in a friends MGA(1800)
It was also a 280 duration cam but with more overlap being 35/65-70/30---possibly slightly stronger up in the revs than the 240 cam but a choppier idle whereas the 240 you can hardly tell it's got a cam in it and driver friendly round town
I'd be tempted not to go over 60deg overlap if you want to use it as a smoothy road engine
A mate had a Waggot cam in his wife's daily which was a ripper -you could just notice it had a cam in it but it was easy to drive , no lumping about and it went quite well in that mid rev range
The specs of that for your interest were--
Waggott-253-- 29/56--60/25----.265" lift@l

I guess you're probably best sticking to your local known products though really, specially with Peter on board to advise you with what he's had good results with but the main thing is to quiz yourself on what rev range you need, do you mind a choppy idle, do you want to be able to lope around town in it etc and then make your decision based on that
It's real easy to get sucked into a big cam cos it goes hard up high but then drive it round at nowhere near the required revs to get the best out of it, better to under cam than overcam
Did I say that-? being a lifelong sucker for big cams
Choose wisely it will be the heart of your engine
willy
William Revit

This thread was discussed between 30/08/2019 and 02/09/2019

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