4.3 heads a few questions
Discussion
Following on removing gaskets looking at valves inlet 40mm so not bv valve has raised lip round combustion chamber as 900T-R mentioned 
questions is it worth changing to bigger valves skim heads. Will be using arp studs on refitting. Don't mind spending if it's worth while also who would you recommend for head work based in Cheshire
questions is it worth changing to bigger valves skim heads. Will be using arp studs on refitting. Don't mind spending if it's worth while also who would you recommend for head work based in Cheshire On the advice of John Eales, I went for the intermediate large valves. On a 94 mm bore they will probably result in pretty much the same airflow ultimately while being a bit more tractable down low.
Having said that, a dyno session showed 300 PS (296 bhp) with the standard sized small valves with a ported intake manifold and big trumpets, ACT twin plenum and exhaust manifolds w/ decats, mapped ignition (123ignition) and a big airflow meter (which is pretty close to the theoretical maximum with 40 mm intake valves on a pushrod engine with parallel valves and the combustion chamber shape) so in standard tune the valves are not really the limiting factor. Pushing for 320-340 bhp with some more upgrades now
Having said that, a dyno session showed 300 PS (296 bhp) with the standard sized small valves with a ported intake manifold and big trumpets, ACT twin plenum and exhaust manifolds w/ decats, mapped ignition (123ignition) and a big airflow meter (which is pretty close to the theoretical maximum with 40 mm intake valves on a pushrod engine with parallel valves and the combustion chamber shape) so in standard tune the valves are not really the limiting factor. Pushing for 320-340 bhp with some more upgrades now
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