1.8 8V DX camshaft choice

Hi guys 

Thinking of running twin 45, what cam would you suggest to go along side the twin 45?

Spec: Rebuilt bottom end, with new oversize pistons, New followers, flowed head with new valves. 4 branch manifold and performance exhaust.

kind regards.

There's a huge choice of cams depending on the full spec, compression ratio, valve springs used, solid or hydro lifters etc.

Standard springs, lifters, pistons etc are good up to 7k but a 290-300 degree cam won't work with a standard 10:1 CR for example that to 45's can feed.

If the c.r is up around 10.5-11:1 then a 276-280 degree cam with 0.430 lift is a good all round option for road use and still be respectable if you do any track days or sprinting.

The 45's will need 34mm chokes to make around the 155hp the basic spec should make. The inlet manifold will need port matching to the head though (head off on the bench job) and will need the ports opening if it's an old type used manifold as they're tiny and will kill any advantage of the 45's. Brand new manifold are miles better but still need a little work to give the best from them.

JMRacing said

There's a huge choice of cams depending on the full spec, compression ratio, valve springs used, solid or hydro lifters etc.

Standard springs, lifters, pistons etc are good up to 7k but a 290-300 degree cam won't work with a standard 10:1 CR for example that to 45's can feed.

If the c.r is up around 10.5-11:1 then a 276-280 degree cam with 0.430 lift is a good all round option for road use and still be respectable if you do any track days or sprinting.

The 45's will need 34mm chokes to make around the 155hp the basic spec should make. The inlet manifold will need port matching to the head though (head off on the bench job) and will need the ports opening if it's an old type used manifold as they're tiny and will kill any advantage of the 45's. Brand new manifold are miles better but still need a little work to give the best from them.

Thank you for your reply.

As to the head its hydraulic, and 45 manifold was used on a dx and ports are nearly same side I have checked that.

Thinking a piper 275 unless I there are better ones to go fit.

Thanks