Head work

[Rumbul]

Hey guys I was thinking about doing some head work on my Jspec . I have a new gt3540 waiting to be bolted on also have a link g4 .

The head was off and all measurements checked 2000 kms ago . Replaced valve stem seals at the same time .

But it's time to get this thing flowing . Can anyone recommend a good cam , spring, retainer , lifter combo ?

 

[BYBY5L]

without knowing alot about ya car, my 2c is kelford and ferrera, pricey but top stuff, i know alot of people in nz with them and they love them, also known people with hks's that have gone to kelford, well im actually one of them, ive got a set of 276hl's waiting to go in place of the hks's

 

[ozyvr4]

Hi there Rex. I would ask Tim about his setup . BC 272's are quite good price & have good results.

 

[BMGTZ]

1mm over size valves in my experience gace better gains than just a set of 272 Bc cams.....but oversizevalves and some decent cams is a different story

 

[brisvr4]

Cam choice depends on what you want to do with the car?
I run BC280's now but I used to run their 272's with BC springs and retainers. Shifted at between 7500 and 8000 and have had no issues.
Next time the head is off it will be getting 1mm oversized valves as per Brian's post.
Last time out at Willowbank with the 272's i crossed the traps at 8000 in 4th and it was still pulling strong.
That's said, my setup suits my needs and may not suit others.

You will get every option under the sun thrown at you with claims that theirs is the best, it's pretty much down to you to research each option to see what will work for you.

 

[Rumbul]

Thanks for the feed back guys . So when you say 1mm oversized valves do you mean the valve stem is 1mm oversized ? (Making them stronger ) or the valve seat is over sized ?

Sorry for the amateur question

 

[BMGTZ]

the valve head is larger in diameter . So the seat needs to be recut to a larger diameter making the opening a larger area. {1mm is about as much as you can go on the stock seats.} The throat behind the seat then needs to be ported to the same size

 

[Rumbul]

Ok that makes heaps of sense , so most good engine machine shops can do this for you ? Is it generally and expensive exersize ?

If I'm running standard valves , could I just install some cams with out taking the head right off ?

 

[ozyvr4]

Yes you can mate, but changing valve springs with the head on would be a challenge, but cams and lifter would be easy.

 

[Rumbul]

Sounds like a good plan oz! At least until I forge the bottom end .

These things are the biggest money pits !!!

I'm on a first name basis with jnz tuning ....

 

[BMGTZ]

the valves on their own are very worth while....and stealth. lumpy idle is sometime a pain right near a cop. I am doing a 2mm oversize head with a new build......finding someone that wont fuck it up is the limiting factor

 

[4piknup]

I noticed you mentioned this the other week in a different topic.
What are the valves stolen from? And is there room for them, like on the cam overlap and between the valves?
I was thinking of this (after you mentioned it) and thought it would really suit the fatter bore size of the 2.4...

Vosenberg heads are right over the road from my place. Bert is really nice guy
Or, galloways in pinjarra have a cnc machine to cut seats...

 

[BMGTZ]

available off the shelf Jack....common thing the DSM boys do so try sources in the U.S.A such as Maperformance.

 

[4piknup]

Had a quick look at manley catalogue other day. But they only list .5 and 1.0 over. Will look harder.
Cheers

Also saw a awesome thread about mivec on intake cam only using some evo9 parts. that would get the jummy up on the converter nicely...

 

[BMGTZ]

http://www.ebay.com.au/itm/250520553700?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

2mm oversize

 

[EVO-00X]

Problem is the bigger the oversize the more metal that has to be removed from the oem valve seat and it compromises its strength and longevity.
With the power thats being made these days out of street driven EVO's, you probably wouldnt bother going oversize valves IMO depending on the power figures you're after.

 

[dakiller]

I'm in the process of building a whole motor for mine.

Definitely get revised 3G lifters, ITM are the brand lots of DSM's in the US use, much much cheaper than oem and just as good.

My plans are Kelford 264 cams and Kiggly beehive springs. The springs are about the best ones money can buy, and while the cams are only a 264 degree, they have a bit more lift and more aggressive ramp opening, so are quite comparable to most other 272 cams flow wise.

I am sticking with stock valves, just because it will cost quite a bit more to get new valves and have them and the seats cut, I'm trying to do this all economically, so just a light lapping to clean them up. Port work will be decided once I speak to the machinist to see how much it'll be,

As to vendors, I made myself on first name basis with JNZ as well, get looked after quite well there, as well as maperformance, they sorted shipping prices that are hard to beat anywhere else.

 

[Rumbul]

I just received my new Slave cylinder today , also replaced all my shifter Bushings at the same time and wow what a difference that made .

Now it's just time to run the engine in on some low boost . So fun driving the old vr4 .

Think it may need the drive shaft rebuilt though