3k - Limited Mods

[Dan]

Alright.

 

Well, as some of you may have read in the General Discussion area, there have been some new regulations brought in, in regards to driveline modifications. Note: we are ONLY allowed to run 3ks, or K's. Don't say to run a 4k or 5k because its so much better than the 3k!

 

Before, we were only able to use the stock head, with limited work done to it, and standard pistons etc. However, now we can run flat top pistons, and any head that will bolt on without modication to its mounting points, manifold or carburettor. Head must be of the same port configuration as stock, ie: 2 port head.

 

My question is, what would be a viable alternative to the standard 3k head, that I would perhaps be able to bump the compression up a bit with. Now, i'm planning on running flat-top pistons; what head would be a good alternative; perhaps a K head??

 

Other driveline modifications that are now allowed (not allowed previously);

- ability to fit any diff that fits into the standard housing, that came as OEM equipment (ie: if a datsun diff fit into the diff housing without modification we can run it, also can I use diffs from ke70s?)

- ability to run any gearbox gearing, providing it fits in standard housing

- limit to 13x6" wheels

 

My current plan (other than engine) is to run the K40 gearbox, with a locked 4:3 (and 4:1 or 4:5 for different tracks); and some jellybeans i've got as rims...

 

Any help or suggestions would be greatly appreciated.

 

Dan.

[Teddy]

1) get a good 3k head

2) get it crack tested

3) shave the absolute mole outa it

4) do some good porting to it

 

5) shave the block some more

 

Twin side drafts & nasty cam :thumbsup:

[Dan]

Sorry, I should have explained more clearer.

 

We've been given freedom in relation to cam's, although you can only run standard carbies and manifolds. Exhaust may change providing no modification to the manifold is made to achieve it. I plan to run a 2" dumpy behind the front wheel.

 

Therefore porting the hell out of the head and shit like that is a no-go zone - we can only 'clean up' the head in respect to head modifications.

 

And, unless twin side drafts were available on stock 3k's released in the Australian public, in a vehicle with four seats - we can't run them either :thumbsup:

 

So, basically, what I'm asking is, is there a more suitable head out there than the stock 3k head?

 

Dan.

[thomo]

k series head and twin down draught(?) carbs of a ke16 fast back, standard, 4 seater, higher comp, bigger ports, crap valve seals but i don't think the rules say you can't run later model standard ones

i don't know what car you have so i don't know bout diffs or gearbox

[Felix]

so you are restricted to factory option carbs?

what fuel are you allowed to run?

standard valvesize?

[Raven]

Twin down-draught Aisan's :thumbsup:

 

Go for it!

[coln72]

Just say that you had to shave the head as it was warped :thumbsup:

 

Twin Aisans are good.

 

Get a set of factory headers - the ones with the twin engine pipes and weld a 2" system onto that.

[Rolla__Boy]

I have a recently reco'd heavily shaved 5K head sitting here doing nothing.

[Dan]

We're restricted to factory option carbs, yes. I'm not quite sure what the go is with fitting optional carbs though, because it does say in the manual that it should represent a base model car.. I will have to make contact with Fabio Martinelli about that...

 

Yes, we are limited to Unleaded fuel with an additive or octane booster (readily available to the public for street use, that only) and the only mods to the ports we can make are just to clean them up a little bit. We are only really allowed freedom in that...

 

I'll keep you in mind if I want to put a 5k head on the 3k Geoff, but I'm looking to up the compression a bit...

 

Wasn't the KE1x released with a K or did it have the option of a twin carb, and was there any KE3x-5x released with a 3k with dual carbs?

 

Dan.

[Dan]

Oh, and factory headers with dual pipes? Please explain!

[lappy]

Twin carbs are a no no :jealous: it says in the book No more than 1 carby and in the back of the rule book it lists what type of carby your car has from the factory and that is the only one you can use

[Rolla__Boy]

This head will up the compression. It's been shaved ALOT!!!

 

It appears to be off a dished piston 5K, so with the flat tops in the 3K, it will be good

[coln72]

Bugger on the twins - were a factory option right up to KE70 I think. I know there are two different types of air cleaners available from Toyota. Can you run a carby off a celica or a datsun? Think they are bigger. An other option is to machine the carby a bit. Think Super Jamie did that when he was running a standard carb

 

Factory headers - cast iron manifold with two outlets. Two engine pipes coming off that which join up under the firewall into a single pipe. Can cut a bit off where they join up into the single pipe and weld a 2" exhaust on real easy.

[Rolla__Boy]

The KE55 I just got has twin pipes like that

[Felix]

i thought pretty much all the ke30 and ke55 series had the twin exit exhaust manifold, and 4-2-1 style system. the ke30's definitely did.

 

i wouldn't use the dished 5k head on the 3k. 3k's have flat top pistons. 5k dished heads have something like 16cc chambers to start with, before skimming. you would end up with something like 15-16:1 CR. think you would be best aiming for around 11:1 or so.

 

with the carb, you could always experiment to see if the venturis from a bigger aisan could fit. depends if you have rules governing the size. you can interchange them between k series aisans reasonably easily. there is quite a variation in the sizes on stock carbs. think they range from 18mm up to 24mm from memory....would have to have a look through my box of aisan carb shit.

Edited June 15, 2006 by Felix