What cams are people running in 8 ports?

[MrNoo]

What cams are people running in 8 ports? This will be an all steel engine on injection in a 1275 S thick flanged block +60" and large valve Arden head. S main caps are these ok to use or do we go down the Swifty route and buy their mains kit and line bore/hone. Regarding use, it will just be a hoon around/track day car.
It is due to go in a 997 Cooper so am slightly torn between the "purists" Amal carbs or injection.

[Supersonic]

It is a long time since I ran an 8-port engine but I recall I used an AEG 637 cam, again I think the part number was AEG 636. That was in my race car which ran a Arden big valve cylinder head on 40mm twin Webbers. The Webbers were so easy to keep right, never ran any other carburettors, thought they were too difficult to setup.

Alan

[Fanfaniracing]

I have a 296 degree Cam in my 1320.

I also run two 40 DCOE Webers and i am very happy with it!

Rest of the Engine is Cooper S with four bolt Main Cap.

Cam and Cap were made for me at APT in the US

[MiNiKiN]

It is due to go in a 997 Cooper so am slightly torn between the "purists" Amal carbs or injection.

Well, why not use the best of both, the "purists" Lucas Mk1 injection

[MrNoo]

It is due to go in a 997 Cooper so am slightly torn between the "purists" Amal carbs or injection.

Well, why not use the best of both, the "purists" Lucas Mk1 injection

Lol!! Not got one of them lying around in the shed unfortunately or I would. I guess a couple of 40's would do also. I will get the engine machined up and put together and hopefully by then I will have made my mind up.
Many thanks.

[Richspec]

286 on a 1380 with MS injection (older road head)
296 on home made Jenvey Injection (older 'race' head)

On my 1293, I've had supersprint? 599? (too much top end for a road car) (newer big valve head)
then onto the newer Minispares Rally Cam (both with MS injection setup)
then tried the rally cam with the rotrex on it and plenum etc
Now going down to 'Road' cam and road head.

I don't need 200bhp at 8000 revs.

[MrNoo]

286 on a 1380 with MS injection (older road head)
296 on home made Jenvey Injection (older 'race' head)

On my 1293, I've had supersprint? 599? (too much top end for a road car) (newer big valve head)
then onto the newer Minispares Rally Cam (both with MS injection setup)
then tried the rally cam with the rotrex on it and plenum etc
Now going down to 'Road' cam and road head.

I don't need 200bhp at 8000 revs.

How did you find the 296? Too cammy? What rpm did it start to get going??

[Richspec]

nah, it was fine, the 8 ports will pull a higher degree cam without being overly cammy. Even the rally cam was something like 300 degrees on the 1293 and pulled well, but it was very well setup on the injection.
I don't know what the figures are for the old 296 8 ports, at a guess the same as the 5 port flavours?, i believe they're gone anyway.

Make sure the big valve head will clear your bores, I was told that the race heads are only suitable on 73.5mm bores.

power bands are just the same as normal ie 3500 onwards they really start to come on strong, the 599 was more like 4-4500 though

The choice of cams for the 8's is really poor sadly, they could probably benefit from updating.

[mk1]

Don't waste your money on Amals.

If you are going to the expense of running an 8 prt, it's not worth faffing about with Amals, they are difficult to tune, on or off & usually spray fuel down the front of the engine.

An 8 port is TRANSFORMED with a good injection setup.

[MrNoo]

Many thanks, yes, injection is the way i'm leaning towards, as you say going to the hog of 8 port may as well get the most out of it, best get saving!!

[Simon776]

My engine has the 636 (effectively the same lift etc as a 649) camshaft; being under a well sorted original Arden 8 port with sensible compression ratio transforms the character making it more driver friendly and useable compared to a 649 in a 5 port.

The Amals on mine are 1970's originals that seem to work very well and don't dump loads of petrol down the front of the engine. No real drawbacks; the first start up of the day is a bit of a faff, it does sound a bit agricultural on tick-over; Amal parts availability is good although Burlen refuse to believe the carburettor model number exists.

[mk1]

Hi Simon,

Good info on the Amals. I think most peoples issues with them are finding someone who can set them up properly.