3/5/7 angle valve jobs?
Discussion
Pumaracing said:
So Mr OP. Aren't your heads finished yet and some new bhp numbers to show us?
No, I am due to get them back this week, they have gone to be fitted up at the recommended valve spring height and one valve is too far out with the others, so has to be machined into the head 15 thou, so they all have 30 thou washers under the valve springs to give the right spring install.i will post up whether good bad, or ugly!
Fingers crossed...
SpeedTalk in the U.S. has an 'Advanced Engine Tech' section with participation by many world-wide. I believe PistonHeads would gain highly from such a sub-Forum where you advanced 'gearheads', world-wide, can concentrate on the finery's of what it requires to make an engine 'tick'. As to Mr. Vizard's question about his up-coming book? If the book is already 'chaptered', define the theories/ideas/knowledge covered, per chapter, in a dozen or fewer written lines, then all Forum participants can comment/question the covered subject matter of each chapter? -Dave- U.S.A.
what's the hole/drilling in the top pic on that inlet port? just curious 
Brummmie said:
I'm off to knight engine services nr silverstone with the heads today, while I'm there I will have the ITB's port matched. But I will go armed with a few questions now.
I'll Dyno it once the work is done anyway.
Get Dave to put the kettle on , and get his Mrs to get the cake out ! will be down there later building up a poxy k series I'll Dyno it once the work is done anyway.
Look forward to seeing what it makes... Is this about as far as you can take this engine now or you got anything else planned??Its up and running, no difference whatsoever. Only the curve alot less jagged thanks to the new valve springs i suspect, but power the same!
It needed a bit more fuel in the midrange when mapped.
Feels a bit more responsive on the throttle, to be honest i think the exhaust manifolds have are out of legs, and they need to go up a size.....
It needed a bit more fuel in the midrange when mapped.
Feels a bit more responsive on the throttle, to be honest i think the exhaust manifolds have are out of legs, and they need to go up a size.....
Brummmie said:
Its up and running, no difference whatsoever. Only the curve alot less jagged thanks to the new valve springs i suspect, but power the same!
It needed a bit more fuel in the midrange when mapped.
Feels a bit more responsive on the throttle, to be honest i think the exhaust manifolds have are out of legs, and they need to go up a size.....
If making new manifolds....may as well attach a turbo or two to them lol.It needed a bit more fuel in the midrange when mapped.
Feels a bit more responsive on the throttle, to be honest i think the exhaust manifolds have are out of legs, and they need to go up a size.....
Long-time lurker who has just spent an enjoyable half-hour reading through this rather technical thread........
I have a question about forced induction and gas speeds at the intake ports.
I understand that with forced induction, you are increasing the density of the intake air and therefore the mass of air that the engine consumes. The denser air should flow at the same velocity through the intake pipework as it would if the engine was naturally aspirated (unless frictional losses are in any way affected by gas density?) up until the point of the intake valve.
I was under the impression (awaits to be corrected having missed something blindingly obvious) that gas velocity is proportional to pressure differential - so on an intake stroke, the pressure differential between the port and the cylinder (until filling is complete) will be higher on an F/I engine than for N/A......so is the gas velocity past the valve (at least initially) higher on an F/I engine?
I have a question about forced induction and gas speeds at the intake ports.
I understand that with forced induction, you are increasing the density of the intake air and therefore the mass of air that the engine consumes. The denser air should flow at the same velocity through the intake pipework as it would if the engine was naturally aspirated (unless frictional losses are in any way affected by gas density?) up until the point of the intake valve.
I was under the impression (awaits to be corrected having missed something blindingly obvious) that gas velocity is proportional to pressure differential - so on an intake stroke, the pressure differential between the port and the cylinder (until filling is complete) will be higher on an F/I engine than for N/A......so is the gas velocity past the valve (at least initially) higher on an F/I engine?
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