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Whats Under Your Bonnet ?

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Only reason i went aftermarket piston was because i had a crack in piston 1 and 2.So i thought might aswell go oversize while I'm at it otherwise would have kept the stock pistons.

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  • :'( So much theoretical gobledegook. Anyone would think that k motors were weak and complicated, when in fact they are the total opposite.   Rad Rolla, do your self a favour and ask how long people

  • Author

I am still decideding whether i will use aftermarket pistons or not.

 

I will decide when i get the engine, and it will depend on the condition of

the bores (and my cash at the time).

 

Originally i was not going to, but i figure if i do the

job, it may as well be done right.

 

Still unsure :y:

fair enuff

  • Author

What else have you guys done ?

 

The more different combos the better :y:

 

So, once again.............whats under your bonnet ?

  • Author
as per my signature

 

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I think i will be running similar duration to your tighe 104 grind. Unfortunately

most of the cam joints down here are not interested in doing profiles for a

k motor and so i will need to give them specs from tighes to work from.

 

But, from what i hear about the quality of tighes work, this is not really a bad thing :y:

I bought a rebuilt 5k bottom end with about 10,000 kays on it for $150

Threw in the tighe 113 (25/65 65/25)from my old 4k, with a 3k double row timing chain.

Converted it to solid lifters (gutted hydraulics), with 3k pushrods and 4k rocker gear.

I ported a 5k head I got from a mates ke20 club car, it already had holden double valve springs and k-line guides fitted.

Ended up with 9.6:1 CR.

Already had pacemaker 4-1 extractors and 1 7/8" exhaust.

Weber 28/36 DCD

 

Minus the induction and exhaust the motor owed me under $500 fitted including a vrs kit, clutch kit and oil/filter etc. Has run like a dream for over 3 years now, only hassle I've had is a leaky extractor gasket and a front crank seal.

 

It is in a ke15 with 5 speed. Averages around 12km/L with all sorts of driving. Has better drivability and throttle response than a stock motor. Makes your average v6 look well.. average. :y: It is cool, when you feel lazy you can putter around roundabouts in 5th and ease away nicely. It will happily rev to way past 8 grand, but it is quicker to shift at 7 and put it in the meat of the torque band. It runs nicely on 95 octane and will tolerate being run on the hottest of days on 92 without pinging if you are desparate.

 

The goal was to build an allround reliable no fuss performance/economy motor.

3K block.

4K crank. Can't remember the size of the pistons, but they were CB Charade with capacity out to 1359.9

Standard height head, but pistons machined down (too high) to give 10.9:1

Hot 202 blue motor valve springs.

25/65 Cam, with about .430 lift.

Balanced.

4-2-1 custom HPC coated extractors, 2 1/4 exhaust.

Twin SU's to start, (really good), ended with twin 40mm Webers. (even better.)

 

This thing sang. Did 5 years work as a PRC rally motor, and still as strong as the day I put it in.

 

Have now gone 2TG.

Edited by Redwarf

My cam is a clive 160 grind.

Edited by harun

  • Author
I bought a rebuilt 5k bottom end with about 10,000 kays on it for $150

Threw in the tighe 113 (25/65 65/25)from my old 4k, with a 3k double row timing chain.

Converted it to solid lifters (gutted hydraulics), with 3k pushrods and 4k rocker gear.

I ported a 5k head I got from a mates ke20 club car, it already had holden double valve springs and k-line guides fitted.

Ended up with 9.6:1 CR.

Already had pacemaker 4-1 extractors and 1 7/8" exhaust.

Weber 28/36 DCD

 

Minus the induction and exhaust the motor owed me under $500 fitted including a vrs kit, clutch kit and oil/filter etc. Has run like a dream for over 3 years now, only hassle I've had is a leaky extractor gasket and a front crank seal.

 

It is in a ke15 with 5 speed. Averages around 12km/L with all sorts of driving. Has better drivability and throttle response than a stock motor. Makes your average v6 look well.. average. :y: It is cool, when you feel lazy you can putter around roundabouts in 5th and ease away nicely. It will happily rev to way past 8 grand, but it is quicker to shift at 7 and put it in the meat of the torque band. It runs nicely on 95 octane and will tolerate being run on the hottest of days on 92 without pinging if you are desparate.

 

The goal was to build an allround reliable no fuss performance/economy motor.

 

Sounds good, (especially the price) :S

 

What advantages do you get from that mix of 3/4/5k parts ?

  • Author
3K block.

4K crank. Can't remember the size of the pistons, but they were CB Charade with capacity out to 1359.9

Standard height head, but pistons machined down (too high) to give 10.9:1

Hot 202 blue motor valve springs.

25/65 Cam, with about .430 lift.

Balanced.

4-2-1 custom HPC coated extractors, 2 1/4 exhaust.

Twin SU's to start, (really good), ended with twin 40mm Webers. (even better.)

 

This thing sang. Did 5 years work as a PRC rally motor, and still as strong as the day I put it in.

 

Have now gone 2TG.

 

How much work was needed to get the 4k crank into a 3k?

 

Could i have a rough price for what all that cost you ?

(i am still working out budgets and working out how much i can afford to do)

 

Thanks

  • Author

Forgot to add;

 

I went to repco and bursons to find out about pistons this morning.

 

Bursons said that because national parts have now gone under they cannot

get acl pistons.

Instead they offered 40thou over, ''precision international'' pistons, for $250.

 

Repco said that they could probably still get acl pistons direct from the supplier,

at approx $320 for 50thou over slugs.

 

The funny thing was that the guy at repco has just moved over from nz and he

said he had a KE30 with a hot 4k, which was then replaced by a 5k he bought off a

mate.

 

It was good to talk to someone who actually knew what a k motor was ! :S

 

Anyway, according to this guy, in nz they get the cheap jap imports and so you can ''easily''

pick up a 5k for $150. He suggested i go onto the nz site 'trademe' and buy one then ship it over.

(not sure what this might cost though)

 

He also suggested i put on a 3k bigport head, which i was interested to hear.

I was not sure this was a good combo and what it will do for the compression.

 

Anyone know?

 

Also;

 

Does anyone know the differnce in port and valve sizes between a 5k head and a 3k-b one ?

 

And, is there space to put bigger valves in a 5k head ?

 

Thanks again to all, and sorry about all the questions :y:

I believe 3K, 3K bigport head on 5K block bumps up the compression ratio.

I think the standard port size on a 3K head is roughly 28mm and for bigport roughly 30mm.

Best bet about if you can put bigger valves into a 5K head would be to see a mechanic. Again nothing is impossible, it just costs money.

Edited by harun

I believe 3K, 3K bigport head on 5K block bumps up the compression ratio.

I think the standard port size on a 3K head is roughly 28mm and for bigport roughly 30mm.

Best bet about if you can put bigger valves into a 5K head would be to see a mechanic. Again nothing is impossible, it just costs money.

 

I've already told you this once in this thread. a 3k, 3k BP, or 4k head on a 5k will drop CR. FFS do a search on dished piston vs flat tops. :S

 

The mix of 3/4/5k parts is to convert to solid lifters, do some searching on that too! :y:

Edited by Taz_Rx

Well the man is thinking of getting new pistons.

I would think he we would go flat top for maybe he wasnt interested in forced induction?

It really dosnt bother me if it drops compression or not because it aint the mods that i will have done.

Edited by harun

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