mc100

Hi all,

could somebody tell me what the difference is between a version 5/6 sti engine and the engine from earlier sti's?

I have for some reason always beleived the heads to be different, in what way I don't know but if somebody could shed some light on it for me.

Thanks guys

Jimbob_Scooby

iTrader: (3)

Hi mate, as far as i know there is no difference between the 5 and 6's. Although the 5 and 6's are different from the early ones. They have different cams and valves i do believe. Some of the early STI's had CDB's as i have just bought an early CDB for my X reg Type R which is supposed to be a version 6 on the year, but got the version 5 spoiler thats the only way to split the 5 and 6's

mc100

Thanks for that.

Would it hurt then if I used a different engine (from an earlier model) in my version 5 sti?

What's a cdb by the way?

Is there any difference in the block of an Sti and a wrx or is it just the internals?

mc100

Any advice us greatly appreciated :-)

mc100

Anyone guys

joz8968

iTrader: (13)

CDB = closed deck block. Does not have an air cavity around cylinder walls - it's all 'filled in' with metal right upto the heads' mating face Stronger than a ODB and SCDB.

STi v.5/6 AFAIK are one and the same engine, in as far as components used, etc.

As said, the v.5/6 STi have superior components than the same MY99/00 WRX. Such as forged pistons (not sure about rods), and freer breathing heads with more aggressive cams, shims over buckets, etc.

joz8968

iTrader: (13)

Any EJ short block (fully assembled bottom end) can easily be interchanged. It's truly 'plug and play' in that any MY's heads will bolt onto any block. To this end, it's best to keep your cars existing heads, as you can keep all the exisitng ancillaries/looms, etc. i.e. just plonk your existing heads on whatever block you fit; no messing about.

The v.5/6 STi heads are very good and will easily flow over 500bhp if you want it....

mc100

That is just the info I needed to know.

Thank you for that.

Would one block be better in anyway that another (a cdb compared to a odb) or does it not really matter too much?

joz8968

iTrader: (13)

CDB can take more bhp than either SCDB or ODB
SCDB more than ODB, so:-

1. CDB
2. SCDB
3. ODB

But the 'runt of the litter' lol ODB is believed to be good for at least 500bhp! anyway. I think there are quite a few running this sort of power through 'em...

joz8968

iTrader: (13)

I wouldn't get too wrapped in what "x"DB it is.. more the quality/brands of forged piston/rods; crank; bearings; displacement, etc.

These are what matters for longevity/big power.... Unless you want to go stoopid power, in which case a CDB should then be used...