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Need Some Help

Featured Replies

Hey peoples, I need some help/advice. I just put a 4k, 5 speed, extractors and ehaust and factory twins in my ke35. I have a 3k bigpot head that I am going to clean up and put on the 4k block. what should I do to the head? and what sort of cam should I go for? also how hard and is it to change the cam on a k series?

any help would be greatly apreciated...

 

Cheers,

hmmm, how much do you want to spend?

 

If you want to go absoluetly crazy, get the ports completly welded shut, then completly re-drilled, get some major valve work and shave the head a bit :greenbounce:

 

As for cam... hmmm...

 

talk to Superjamie, Felix & Redwarf.. they are the K expirts off the top of my head .

Before you do anything, work out a budget. How much do you want to spend? Money = power. As I saw on another forum, "How fast would you like to spend, sir?"

 

As for changing cam in situ? Not easy. Never done it myself, and have no interest in doing it. Would be quite difficult. For me, it's an engine out job, and do it on a stand.

 

Where are you located?

 

R

If you want to go absoluetly crazy, get the ports completly welded shut

I didn't think the sentence was going to go further than this. lol

  • Author

ok firstly I'm in tas, secondly I don't want to spend heaps on the rolla as I already have another money pit/ car.

the rolla is only really going to be used for club events and playing on some gravel roads.

all I intend in doing is tidying up the head, bigger valves, spings, a cam.

and maybe a pair of webers on the twin manifold thinking a pair of 28/36 thats if I get game enough to run some huge compresion and run it on avgas.

now if anyone can give me some constructive sugestion on valves, cam and spring that would be great.

 

Cheers,

Okay. Bigger valves aren't really necessary. Mine doesn't have them, and it goes fine. The biggest I've heard of being used are Gemini valves, but that's your decision.

 

I used to run a Wade 169x grind cam, 30/70 .269 lift. Great user friendly club motorsport type cam, worked well with the factory twins. Wade's used to be, and I think still are, in Nth Melbourne. Any decent engine builder can hook you up with the correct springs.

 

I'd look at getting something like a pair of SU's rather than going for twin downdraft Webers. Even a or a pair of Side draft webers, as there's a good amount of space on a 35 to put aircleaners (always a problem on earlier KE's). However, Webers are as dear as poison. But hey, that's just my opinion.

 

Forget about Avgas. You can't run it in club competition, unless you have an Historic log booked car. About 10.5:1 CR is what you're chasing if you want it to run well on PULP.

 

Hope this helps.

 

R

  • Author

cheers, for that. 10.5:1 is what I should acheive from the head swap I think.

 

and as for the carbs well I know I should be able to pick up a pair of webers for under $200.

what sort of su's should I look out for? and what sort of dollars should I expect to

pay?

and from everything I have read I believe that I should use holden 202 valve springs, 4k or bigger valves.

I'm not going to touch the bottom end yet. but when I do all I'm going to is freshen it up a bit.

 

is it worth considering running a elcetric fuel pump instead of the mechanical one?

and I have seen both good and bad results from thermo fans so I'm unsure if I sould get one or not.

 

the car is already fun to drive I just want it to be funner.

I have non-standard 202 blue motor springs in my motor. Springs depend on Cam. Decide on the camshaft, then chase springs. There is a set formula, and as I say, any good engine builder should be able to advise. I know Crow cams often do springs to match there cams.

 

I paid $200 for my 1-1/2" SU's. (HS4's). Add to that a manifold, and a linkage set-up. I personally don't think the downdraft webers will work as well as you would like. You'll have to custom set-up linkages anyway for your Webers if you get them.

 

A good pair of Weber side drafts are about $400 to $500, plus set-up.

 

As far as putting the K head straight onto a 4K, I don't know what the CR would be, bu I know people in here can definitely tell you. I don't think it will be as much as 10.5:1 without shaving a fair bit of the head.

 

Cheers

 

R

  • Author

well I guess I'll have to take a bit off the head then...

and I want be going through an engine builder I'll be doing it myself...

I think I stick with the standard twins till they can't suply enough juice.

  • Author

yeah I was already planning on doing that when I got new valves.

is there anything I should specificly get done to the head when I take it to the machine shop? as I will be doing that this week some time...

for what you want to do, i would get hold of a 25/65 cam with 400 thou lift at the valve. with a port cleanup and valve job it should give you a strong wide powerband from 3000 to 7000+ RPM depending on the head type, induction and exhaust setup.

 

if you keep your max revs to around 7500, you don't need to worry about balancing or larger valves or anything like that. you can also get away with factory springs running 400 thou lift. really you don't need any flash head, just make the most of what you have available as you can always skim the original to get up around your desired CR.

 

this sort of level of mods will complement your twin downdrafts nicely. you could also go to a small weber if you are chasing better economy for a daily driver.

 

if you already have a decent bottom end, i've found you only need to spend around $400 to put together a tough streetable engine, not including boltons. providing your valve guides are good, if you supply your head dismantled and cleaned, it should only cost around $100 for a skim and 3 angle valve job. add $100 for a cam regrind, and $200 for gaskets, seals, and incidentals.

  • Author

felix are you saying not to use the bigport 3k head or to use it?

  • Author

oh and is there any trick to getting the cam in and out or is it just going to be a royal pain in the arse?

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