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A2 vs BCF2 cam?
02GF74 - 9/11/07 at 10:28 AM

Was gonna put data about these but the Burton website details for the A2 cam does not match that on the sheet, details of whchc I cannot recall exactly but go something like this:

BCF2 FAST ROAD
in: 37/73 ex: 73/37. FULL LIFT: 9.65 mm DUR. 290deg. 2,500-6,000

A2 FAST ROAD
in 35/70? ex 70/35? LIFT 9.4ish mm DUR 285
3,000-6,500

Also power bands are from memory.

So in summary the A2 has less duration and 0.2 mm less lift vs BCF2, timing is earlier and power band is shifted up 500 rpm. Cam experts should be able to say what each of these do for power/torque.

So with that little information, which of the two is better for me if I am after best acceleration from low speed and medium speed e.g. overtaking? Not interested in top speed.

MikeRJ - 9/11/07 at 10:46 AM

BCF2 lift Inlet 9.69, Exhaust 9.59
A2 lift Inlet 8.86, Exhaust 8.81

The power bands quote in the kent catalogue should be taken with a pinch of salt, it depends heavily on the rest of the engine.

The A2 is a an old cam, I would have expected the more modern BCF2 to be better, but I havne't tried either so can't really say.

I can however recommend the BCF3, gives an impressive gain in power and has very a reasonable idle. This has less duration (284) than the BCF2, but more lift (about as much lift as you can use without modifying pistons).

Marcus - 9/11/07 at 12:22 PM

Is this a Kent A2 or the Burton power one?
There is a difference.
I was recommended a Kent 234 or 244 by Mr Kent at the Classic motorsports show last year - They said the A2 was much better for the pre crossflow. The BCF2 is a high torque cam - no bad thing in a seven, but I went for the 244 as Caterham used to use it in their 135bhp Super Sprint.

amalyos - 9/11/07 at 01:02 PM

I can't comment on the other cams, but I used the Burton A2 cam in my 1300 Sport Escort 22 years ago..... ahhh memories.

That went very well and I was pleased with the performance, although I did flow the head and change the pistons.

thunderace - 9/11/07 at 02:52 PM

i went for the bcf3

http://www.race-developments.co.uk/special.htm

£45 from cams

Volvorsport - 9/11/07 at 04:05 PM

i had an A2 in my xflow way back when too .

teh main difference is the A2 doesnt need valve reliefs in the pistons .

if your stuck about deciding ring East Lincs Motorsport , hell tell you straight away .

02GF74 - 9/11/07 at 04:47 PM

bcf2 doesn't need cut outs but bcf3 does.

I think the 234 does as well - need to look up the burtpon cam spec sheet to confirm.

so it seems bcf2 is the "better" opf the two.

david walker - 9/11/07 at 06:59 PM

BCF3 doesn't need cutouts and is IMO by far best cam for X'Flow without modifying pistons

bigrich - 10/11/07 at 05:26 PM

BCF3 used in my old mark1 no piston mods but a little lumpy at idle, pulled really well

ande - 23/7/15 at 03:22 PM

sorry to dig up an old thread but i am searching for a definitive answer to my cam situation, lots of people reckon the bcf3 doesn't need piston mods, i have a 1300 fwd crossflow with a bcf3 fitted, +40 pistons and i have about 1mm pv clearance, been told i should have them machined, it also has an adjustable cam sprocket, could this be adjusted to gain more clearance?

Paul Turner - 23/7/15 at 04:10 PM

quote:
Originally posted by ande
it also has an adjustable cam sprocket, could this be adjusted to gain more clearance?


You can indeed adjust the timing to get more clearance but you would not get the optimum performance since the manufacturer will have developed the cam to work best at the recommended setting. Set to timing too far out and chances are it will run very poorly.

Why don't you just take all your parts to a well respected engine builder and let him build you an engine that actually works.

Since you are asking so many questions it obvious you simply don't have the knowledge or experience.

MikeRJ - 24/7/15 at 01:52 PM

quote:
Originally posted by ande
sorry to dig up an old thread but i am searching for a definitive answer to my cam situation, lots of people reckon the bcf3 doesn't need piston mods, i have a 1300 fwd crossflow with a bcf3 fitted, +40 pistons and i have about 1mm pv clearance, been told i should have them machined, it also has an adjustable cam sprocket, could this be adjusted to gain more clearance?


No, you do not adjust cam timing to gain the best piston-valve clearance. Cam timing is adjusted to get the best power curve from the engine (i.e. best compromise between peak power and mid-range torque) and the pistons should be machined if more clearance is required.

It's pointless doing things the other way around, you could end up with an engine that doesn't even run as well as a standard one. To be brutally honest, if you don't want to put the work in to build the engine properly, or you can't afford to get the engine built professionally then you would be better off sticking to the standard Ford cam.