Question about porting head
#1
Question about porting head
Im pretty much ready to bring my head and block to a machine shop to get decked and figure out what bushings I need, etc. I've heard about wanting to get some places on the head ported for better airflow, what should I ask my machinist to have done because this the first time I've ever been to a machinist. Here is what I currently have in plans
- Line HONE for new ARP Studs
- Head Deck
- Block Deck
- Check Cylinder walls
- Figure out bushing sizes needed
Is there anything Im forgetting? Any comments will be greatly appreciated, thanks!
- Line HONE for new ARP Studs
- Head Deck
- Block Deck
- Check Cylinder walls
- Figure out bushing sizes needed
Is there anything Im forgetting? Any comments will be greatly appreciated, thanks!
#2
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The machinists sometimes call the truing of the head and block mating surfaces "touching off" when they only remove the smallest amount of metal. You don't want to remove more than necessary to get it true. If you say "decking" without qualifying that term, they may remove more than necessary to try to raise the compression ratio, which is undesirable in a turbo motor.
Porting will give very small increases and is labor intensive and therefore pricey. Opening and smoothing the bowl behind the valve seats is where most of the gains are found. The machinists know this. Unless it is a competition car where every fraction of a second of lap time is incredibly important I don't know that I would spend too much money on it. That being said, my head is ported. But I got a good deal on it.
Porting will give very small increases and is labor intensive and therefore pricey. Opening and smoothing the bowl behind the valve seats is where most of the gains are found. The machinists know this. Unless it is a competition car where every fraction of a second of lap time is incredibly important I don't know that I would spend too much money on it. That being said, my head is ported. But I got a good deal on it.
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