ScoobyWhite

I do not know if you that search the top of HP change in this engine the cams!
I would like your opinion, please!

I see that HKS introduce this new cams for our car:
http://www.hks-power.co.jp/products/...ej20/ej20.html

I have a EJ20 Phase2 and I think that this cams are like bolt-ons and do not need tune or anything that we are not ready! - Just Fit and power you will see


Thanks

Tim W

iTrader: (1)

You will have to remap your ecu to see the true benefits of different cam profiles...and going down the route of buying Jun or HKS cams is very expensive, even reprofiled cams from people like Kent or Piper aren't cheap, especially when you consider the small headline figure gains they will make (although cams can improove power and torque accross the entire rev range.

It's not really worth going down this route unless you have already done everything else, including building a strong engine with ported heads...

ScoobyWhite

So what is the changes you do in the heads??

Regards

Tim W

iTrader: (1)

Had all the ports tidied up along with the combustion chambers, new one piece valves, double springs, top hat underbucket shims, new buckets and finally the reprofiled cams...it ain't cheap either

ScoobyWhite

And only the cams (valve springs included or not) anyone try this setup?? What was the increse/results that you have??

Regards

Fangoria

iTrader: (1)

Yes I'm interested in this also - cams only as so-far I have not heard good results on cams only

ustolemyname??stevieturbo

iTrader: (1)

I would imagine seeing as its very possible to get well over 400bhp using standard cams, very few bother upgrading, until well beyond that level.

IMO your money would be better spent elsewhere.

Fangoria

iTrader: (1)

..........and once you start touching over 450bhp you start to get other problems like inherent weaknesses with Cylinder heads which I know quite a few people in that power level have had

ustolemyname??stevieturbo

iTrader: (1)

What sort of weaknesses ?

Engineer@Uni

Gentlemen, there is one undisputable fact about turbo engines. The cam design matters verry little. Intake is forced, and hence even low lift, small duration cams will alow plenty of air in. Exhaust is also forced for the exact same reason. Much more exhaust gas makes more pressure and hence better exhausting of gasses. When tuning a naturally aspirated engine, exact timing and lift is mandatory not only to maximise the scavenging effect of the overlap but also to minimise losses from the cams (might sound excessive but cams in F1 engines cost upwards of 16hp in losses).

Even high horsepower skylines keep the stock cams. As has been correctly stated unless you're after very high power figures and highly refined engine tuning setups Cams are a very expensive mod for a very low hp gain. Also, the diagrams in the link posted are fairly pointless: If the ECU isn't remapped to suit the new cams, bolt-on alteration of the valve cycle doesnt mean anything. You could well find that the cams that perform the best with a remap actualy drop hp with the wrong ECU.

ustolemyname??stevieturbo

iTrader: (1)

Different cams can make very worthwhile gains on a turbo car. I think you will find most of the big power Skylines, Supras, and now a few of the Subarus do use different cams.
They are making over say 250bhp/litre, in some cases more.

Spending £1k or so to buy, then labour to fit cams to a pretty standard Subaru engine is a complete waste of money IMO, which is my answer to the original question.

Once you are past say 500bhp, then maybe its worth considering. Not really before then.

Bob Rawle

Cams can make a huge difference, the STi5/6 cam set is far better breathing than the equiv Eurospec that you have, in addition fitting vernier cam pulleys will further increase peak power, mine rose by some 1200 rpm after fitting verniers (from 6400 to 7680 rpm), suitably remapped of course. The head castings are identical on JDM and Eurospec of these model years.
In addition the EJ207 engine is capable of running far more ignition than the EJ205, the only differences are pistons (cast v forged) and .... cams. Rods, block, crank is all the same.

If you are thinking of changing then you should also look to other things as well, cast pistons are a limiter.

Re head limits as mentioned by Steve he is talking about the micro cracking that occurs on virtually all the Phase 2 heads, if ignored this eventualy works its way thro' to the water jacket, mine did but I had been running 1.9 bar for 40,000 miles. Happens even on std engines.


bob

ronin_hungary

iTrader: (6)

I have sent you an e-mail, regarding STI5/6 cams...

Cheers,

R.