sti heads V gtb heads

[rustyford84]

what is the difference between sti/wrx heads compared to gtb heads?

[Marky]

Need to be more specific which years you\'re looking at

[rustyford84]

oh sorry I have a single cam ej22 I got told to put v3-4 wrx heads on it but I just found some 97 gtb legacy heads just want to know what the difference is thanks mate

[funkytown]

if they are revision B or C gtb heads they will be better than the WRX heads,

If they are revision A heads i would probably go with the WRX heads.

not withstanding compression ratios you will need to think about, wiring it all up and manifold selection, and whether the internals are suitable for turboing, or keeping na, and if NA what you think Turbo heads are like for that purpose.

[rustyford84]

oh wow that\'s sounds technical I will be putting aftermarket pistons in and was hoping to keep my intake as it wont be the typical top mount intercooler set up as I want to build a twin turbo (one per bank) not primary secondary set up

[funkytown]

if you are getting pistons, i would be also getting at least a set of factory STI / GTB rods, or forged ones. NA rods (assuming an NZ 2.2) wont like boosty boost for long.

Errrm regarding the intake manifold - im not sure your factory 2.2 one has the same bolt pattern as the wrx / GTB heads pattern. you should check first.

Using a particular manifold has nothing to do with the turbo application you want to run. Both NA / Single & Twin turbo applications run the same orientation / shape / design manifold for the most part. (i know some of the later NA ones run tricky center plenum set ups however) Again assume you have an old NA 2.2.

Given manifolds are all mostly identical this has no bearing on running FMIC / TMIC or direct turbo -> manifold.

sounds like you meed to do some more research around what you\'re trying to acheive, or describe it here some more to give us \'internet helpers\' a wider perspective.

[rustyford84]

sorry don\'t mean to be a pain im new to the suby world haha yes I have a 92 NZ new 2.2L have been told a few things from the wreakers here in Hamilton but I think there just trying to rip me off if I have to rebuild from scratch I will but id like to keep my 2.2 as have been told by lots of people they are one of the strongest blocks and I like being different haha

thanks for your help though mate much appreciated.

[funkytown]

your not being a pain at all just trying to help in the most constructive way.

So as it turns out i also have a 2.2NA block that i have equilavent GTB heads on (actually v3/4 sti) but as close as you get. i turned it into a turbo block but cost quite a lot of money to do.

Some myths, unless you have a closed deck - ie the top of the bores are mostly filled in they are not the strongest type around. They are simply an open deck, and the crank is a center trust design (worse than rear thrust). In this regard you are basically being fed porkies. If its a closed deck - its a minta and worth a tonne of cash but i doubt that.

If you want to run a factory boost levels, on factory turbo sizes then the open deck / center trust design is fine and no need to change. If you want to run beyond 250wheel KW then you might reconsider that.

With respect to pistons and rods i think i\'ve covered. At a minimum you want to consider changing to a turbo rod, not NA rods, as they will fail. and basically the same applies to pistons, but makes the CR ratio turbo freindly (with the right head gaskets).

You can then bolt on the required heads and away you go. Please go and work out what the bolt patterns are - they have a known change in the turbo stuff between 97 GTB like you say and 98+ GTB, and the same in the WRX / STI world. The NA stuff im pretty sure is somewhat different again (particularly the SOHC stuff). Then comes the wiring..!!!

turbo 2.2\'s are really fun and go well btw. hopefully the size of the mission doesnt discourage you - just be aware of how big it really is.

[Joker]

was gunna wade in but Funky pretty much answered it I believe he (or another user) has physically tested the differences between V3/4 STI and similar aged GTB heads

and the only difference was about 3 degrees on the exhaust cam? Other wise [almost] identical

Flow on a TT is pretty darn good and that goes for the TMIC\'s on those Dinosaurs, \'upgrading\' to a bigger intercooler is a downgrade on a 97/98 BG GTB

(there is a flow test chart around somewhere

my \'race\' motor I have also has CDB (Closed deck block) and TT heads and was putting out 280kw at one stage in its life [single T setup in car about 3 owners before me]

[rustyford84]

if its ezyer for me to keep single cam heads I will I am however looking for an other 2.2L block but no one seems to have an empty one and im not paying $800+ for a motor that needs a recon and I cant pull mine out yet as we use it every day

you guys are really helpful thanks

[Marky]

Genuine question (not being a dick) - why not just drop in a good 2L WRX / legacy motor as-is?

Unless you have big big goals no point spending up on forged bits and bobs

Although I guess that train of thought ends up with "why not just buy a 3k WRX and be done with it" I spose

Can just see it being less heartache than trying to build up an n/a motor from scratch (and the clutch/gbox/certification $ that comes with it)

If not carry on and if in doubt ask on here not the wreckers

[gotasuby]

Sas may have a empty 2.2 block. Maybe best to pm him

[funkytown]

a 2.2 block is much cheaper than that dude!

its worth pointing out at this stage too, that all 2.0 NA and Turbo, 2.2 NA (and turbo if you can find) pre 98 are all the same

so you can pick and match all sorts of bits.

ALSO the rods from all those engines are all the same geometry too

its just the pistons changing from 92mm to 96.9mm to give the increase in capacity.

[rustyford84]

no you have a good point there mate, yes this dose sound like its going to cost a lot more than its worth if anything I would rather work my N/A motor as it is very torquey and is only FF not 4WD at the end of the day I would love a TT legacy and there only like around $2000 on trade me

[rustyford84]

I got told I can get 55thou out of a 2.2L ?

[funkytown]

you can get what now? sorry i dont understand what your question is in relation to

[rustyford84]

sorry I meant to say I got told you can bore a 2.2L out 55thou over pistons but not sure if that is true or not

[funkytown]

oh you can overbore them yup, generally we talk about 1st and second oversize, being 0.5mm and 1.0mm over the factory size, and applies to any subaru EJ (or other rebuild AFAIK).

I just quoted you the factory piston sizes. For the record i run 97.5mm pistons in mine as first oversize 2.2\'s. But most people only ever quote the CC of the original donk. 2232cc is 1st oversize in 2.2 land afaik...

btw i use those instead of thou/inchs as im newer school and or not from the US.

[rustyford84]

haha im old school iv just come from V8s so still getting use to all the newer talk eg Kw etc

[funkytown]

cool cool, note also the subtle but significant difference between KW and WKW, the first kw at engine and later engine at wheels.

hope you have had an enlightening morning here