2JZ head porting.

[2JZR31]

I think a car like yours should have this head. It will need it.

[21OWA]

haha yeah thats what im thinking
im not sure how far my guy up here was going to go with the head
if TK is going "all out" on this head then im really keen!
ill also be going 1mm oversize valves, new guides, new seals, new locks thats all ferrea gear and also going double springs and titanium retainers
i could even stay std size valves if TK wanted it that way, its proven that std valves can go well over 1000rwhp by Ken Henderson

only thing is that the head will need clearancing for the high lift cams

i sent TK a pm and will see what he says

[2JZR31]

And in all reality the same money will give me easy 10's with a new converter and tires

[21OWA]

haha i think u will get 10s by just running DR's lol

im after a little bit quicker than 10s tho :D
also, the turbo i have should make full boost by 5000rpm with a 1.01rear, maybe even quicker if TK does my head

[Rz]

TK , im kinda on a mission to have my car going atm after some major changes so ill have to turn your offer down.

but ill make a little contribution to thread you may be interested in.
the biggest problem i see with the exhaust ports on these motors is not the ports themselves , but the manifolds that get bolted to them , as in pretty much every one ive seen (mine included) does nasty shit to the gas flow as it exits the head.
these pics should explain it better ...

standard ports :





fine with the standard manifold in place ... as it closely follows the angles of the ports :



but then we go and do this to it :



:knock:

HTH

[Rz]

Nope!, cutting the seats & facing the valves raises the tip height - I just set the head up with the cams & buckets in but no valves etc, then just push the valves up & measure the clearance then grind the tip of the valve down to get it right.
Haven't bought a shim for years...

You in?

im pretty sure the valve tip finishes dead level with the face of the retainer on these motors ?
allways thought shims are the only way to do it , unless you grind the retainer aswell .... feel free to correct on this one as i really have NFI.

[pH@tTm@N]

yeah rz thats exactly it eh. although it cant be all that bad since the big lads would go twin turbo if it was so terrible???

21OWA it would be cool to see the before/after at a few differnent boost levels with your gear by the sounds.

[21OWA]

yeah but thats the problem if he uses my head tho
i cant give him b4 and after results, just b4 and after flow figures unfortunitly

as for the manifold and curves ect, aslong as the curves/joins are smooth than it shouldnt really matter to much
even the best exhaust manifold on the market for the 2J is the same way


and btw, that manifold is $2399US!! so thats $2890AUD!!

cheers
Troy

[Rz]

my friend .... just because someone claims to have 'the best' of something on the market and gives it a price tag to match , means nothing to me and most of the members on this forum.
i can assure you that manifold makes no attempt to address the issue i mentioned above , and infact it probably makes it worse.
does it mean its rubbish ? of course not , but its no better than any other manifold at that point.

[flopper]

just out of interest TK, how do the 2JZ figures compare to some of the V8s you've done and things like a recent Commodore engine or a Falcon 6 (SOHC or DOHC). do you have any figures from a motorbike engine or something like Honda engine that you might have worked on?

[TK]

RZ - believe it or not, the manifold design used is not that important, so long as it dosen't bottleneck the flow it's not a problem.
Hard to explain untill you see the before & after of the ex bowls & short turns - that's where the real flow restriction is.
It's irrelevant how much the ex manifold flows when the biggest restriction is right at the start of the exhaust tract.
This is the biggest point I'm trying to make by doing this, you can spend as many $$ as you want on bolt on's, but they can't overcome the limitations of the factory head.
You could use a log manifold & get better results with a ported head than you would with stock head & a mega-dollar aftermarket manifold, of corse using both is better still.
What I want to do is prove beyond doubt to turbo guys that porting is a very effective way of increasing power and drivability on boosted engines - at the moment the biggest focus is on shoving bigger turbos on to get more top end power without any finese.
Porting can allow a boosted engine to make the same power on lower boost with greatly reduced lag time & far superior drivability - but for guys only interested in dyno figures (& it would seem too many of the turbo brigade fall into that category) it dosen't seem that attractive.

flopper - for the power they produce they are horrid (going by flow figures posted earlier), stock heads seem to be completely unsuitable for boost - I don't know what toyota was thinking, stock 1970's v8 heads have better intake/exhaust ratio (although not as much overall flow).

21OWA - I'd prefer to use stock valves, mostly because that's what the majority of guys will be using.

RZ - what would it take to convince you to hand your head over?

TK

[pH@tTm@N]

yeah come on RZ - we want to see 12's out of this improvement.

[TK]

Update :
A local guy has come forward with just about the perfect car for this, thanks to Supercrown for pointing him in my direction.
Level of mods is spot on, car has a good development history & dyno sheets of it's current output, better yet currently the manifolds are off so it isn't that much more work to remove the head.
Plus he's a local, so freighting the head is not a problem.
Head is coming off over the weekend & all going well will arrive here monday night.
He'll be along here in the not to distant future to post current specs on the car & a dyno sheet.

Let the fun begin!

TK

[Dansedgli]

Sweet, this will be interesting.

There is a tuner in wa who tried doing headwork on a BA motor and found no gains and went back to a stock head. He was already making 510rwkw.

Thoughts? Did he do it wrong?

[21OWA]

sounds good
will be intersting to see what flow figures you get out of it b4 you start and then after your work on it

cheers
Troy