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Valve, Head Cleanup

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I figured it must have been, the welded back of the head threw me a little. The combustion chambers seem a little deeper than I was expecting, but fair enough! :)

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  • Author

I'll measure the port sizes and confirm. In the engine manual it was showing that something bolted onto that bit that is welded up.

You're probably reading from a 4k manual (is it a 4k bottom end? - Look for engine number).

 

4k's had either a blanking plate to block the hole, or a similar plate with a water outlet to the heater box on it.

So I bought a valve spring compressor from supershit auto for $50

I made mine.

Unfortunately there is some very extremely shallow pitting on the valves, combustion chamber but luckily not the valve seats. This ment I didn't get a mirror finish poilish with the 1200 gritt but meh..... It is a shiteload cleaner.

I'd be careful with the pitting - can possibly cause hot spots which can lead to pinging/knock/etc etc.

While you've got the head off give the intake/exhaust ports a clean up as well - wouldn't go any higher grit then, say, 320 (400 at the most). Need a bit of roughage to keep the air/fuel mixed.

  • Author

Yeah I'm borrowing a dremel with a fine grinding stone to take out the pitting.

My fingeres are completely fudged from all the fine sanding. I have only cleaned 2 cylinders :)

  • Author

Well I can definately say the ports are larger than normal. The intake manifold does not line up with the ports.

The head has roughly 33~34mm ports and the intake manifold has 27mm ports.... Whoever modded this car before me was hopeless......Or just ignorant.....

Anyhows i will be visiting the exhaust shop to pillage some pipe to weld up a new manifold.

Might also look at doing the quad carby setup as I have nearly finished cleaning the bike carbies :)

 

Should have the head all cleaned up and shiny tonight as I didn't get a chance to do it over the weekend, going to my mates workshop and borrowing his tools :P

Track down a 3k-b manifold.

  • Author

I'll see if I can but I won't hold my breath....

  • Author

I've looked in the for sale section and also the wanted to buy but alas.... nothing.....

Someone in Adelaide was already looking for one but they had no such luck.

If you do find the single carby manifold I'd be keen.

Would the single carby manifold use the same carby flange as the 4k's? If not then I will make one myself....

Simon are the 3k, 4k inlet manifolds the same OD as the bigports?

 

Could always do a port match and hope that it does not affect it too much.

  • Author

But that would only be matching the ports at the head. Would that not put to waste the big ports?

But that would only be matching the ports at the head. Would that not put to waste the big ports?

 

Depends how far back you port it, The smaller runners can speed up the velocity too.

Simon are the 3k, 4k inlet manifolds the same OD as the bigports?

 

Could always do a port match and hope that it does not affect it too much.

 

Yeay mate externally they look the same except the fact the single carb BP mani didn't have a brake booster line.

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