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K Series Port Sizes

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Deleted

Edited by Sbox

From what i`ve seen, the 5k intake ports are a couple of mm. larger than the 4k ones. :drgrim:

Deleted

Edited by Sbox

name='tojo2' date='Jan 10 2008, 11:30 PM' post='219384']

From what i`ve seen, the 5k intake ports are a couple of mm. larger than the 4k ones. :drgrim:

 

PM me a pic and I will add it to the post, this sort of stuff belongs in the FAQ. Once we get it sorted.

 

 

Will do. Wont be home until weekend though.

Sbox, from what I've seen over many years of playing with k series motors:

 

Top is dished piston 4k/5k (small combustion chamber, metal plate on back of head with protrusions under no1 and no4 spark plug holes).. approx 28mm intake ports.

middle, normal flattop 3k/4k (ke3x-ke70).... approx 25 mm intake ports (metal plate on back of head)

bottom, k/3k bigport. (ke1x-ke2x).... approx 30 mm intake ports (has welschplug on the back of the head)

^^^ YES... I have a complete JDM 4K dished piston motor in the shed running and a 5K dished piston motor. BOTH heads are the same. Ports on 5K are slightly bigger I have found on dished piston motors same as my JDM dished piston 4K.

 

philbey do you also have a dished piston 4K? If so would you part with the push rods if your looking to upgrade to a 5K or something one day?

 

As for your heads Sbox. The dished piston heads have a cast lug under spark plug 1 and 4 tube hole so that is how you identify them.

 

Your middle head is plain and boring.

 

The bottom one is an overrated old probably cracked 3K big port head. Shit valve stem seals in these cylinder heads so a must is to covert them to a later model valve stem seal arrangement.

 

Also big port heads were on the more high compression K motors. So they usually will give you higher compression than normal so it will increase your CR.

 

And from what i can see in the photos the 2 bottom cylinder heads are out of a KE20 due to the water heater outlet pipe and how it is situated.

 

Also 5K came out with hydro lifters normally these motors usually run dished pistons. NOW there are some do exist 5K with flat top pistons and solid lifters and with solid lifters you need adjustable rocker gear. There rare to find in solid form in a van etc. BUT can be converted easily your self. 3F Toyota lifters, longer push rods :fuzz: and then some ke70 4K rocker gear (I used ke70 3K as well prob less wear and steel rocker posts). But have a CLOSE look at the for sale threads on this forum. There is a flat top solid lifter 5K going cheap in QLD near me right now..LOL Look really hard but.................

 

 

Cheers

Cameron

Forgot to add. K motors and 2K motors have smaller valves than normal 3/4/5/7K motors SO check your valve size in the big port head as if it is an early big port will have smaller valves also.

 

Cheers

Cameron

Sbox, from what I've seen over many years of playing with k series motors:

 

Top is dished piston 4k/5k (small combustion chamber, metal plate on back of head with protrusions under no1 and no4 spark plug holes).. approx 28mm intake ports.

middle, normal flattop 3k/4k (ke3x-ke70).... approx 25 mm intake ports (metal plate on back of head)

bottom, k/3k bigport. (ke1x-ke2x).... approx 30 mm intake ports (has welschplug on the back of the head)

 

 

Makes sense since my 4k heads are for flat top pistons and the 5k is dished. Havent come across a dished 4k yet.

 

Do the dished 4 and 5k heads have the same cc combustion chambers?

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