boomini wrote:
Is there such a thing as too big of an intake valve??
Yes it can be too big depending on the port shape, especially the small radius, compression ratio and the cam, because a sudden change in area will slow the gas speed down dramatically and this is not what you want as it enters the cylinder. You want it rushing in at max speed cramming as much in as possible to get your volumetric efficiency up.
But it can definitely be too small too, depending on what the port, compression cam, rockers etc are.
Without pulling yours apart and giving it to a true expert (i.e. not me) then you won't know for sure.
But the rockers are relatively easy to change and set up (this is critical) to see if it makes the difference you are looking for.
I would sort out the missing first, that will really kill your power. I had a broken dizzy at an event that made it intermittently run on 3 cylinders. It was still really good, but was not what it is when all four are running.
Also check your valve clearances. Uneven wear or manufacturing tolerances in the whole valve train can mean different durations across each valve which will rob a few hp. Measure the opening of each valve and duration at 50 thou lift to optimise the timing and duration across each one. It is fiddly but can gain that few hp back again. Refer to the Project Small Bore part 2 links below.
Graham Russel did a good three part article on an 1100 engine
http://russellengineering.com.au/projec ... -bore-pt2/Which is also on minimania, which I find easier to read
http://www.minimania.com/Project_Small_ ... inder_Headcheers
michael
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