My new liberty with mods :)

[jslayz]

Perhaps all the boost is being blown out the exhaust......too much overlap. Intake sounds MONSTER.
They checked the cam timing yeah?

J

[dr20t]

Gb - jslayz makes a potentially valid point here

Have someone sit down and calculate the dynamic compression ratio - I know this is almost impossible without pulling the motor apart, but I'd guestimate combustion chamber volume and the rest should be easy to figure out

Mick

[kiahatsiu]

If no one knew what the cams were, how would have they 'dialed them in' correctly?
I suspect the issues with this car are going to be resolved shortly. Fingers crossed.

[<GB>]

well danny doesnt know what it is, ive always said its cam overlap thats caused this issue. who knows

mrt would have selected the cams surly someone would have said something about them when ordering them...

revzone fixed the engine the second time around and they said they had dialed the cams in.


danny thinking the cam timing is correct.

Gb - jslayz makes a potentially valid point here

Have someone sit down and calculate the dynamic compression ratio - I know this is almost impossible without pulling the motor apart, but I'd guestimate combustion chamber volume and the rest should be easy to figure out

Mick

it might have to come out anyway, if it does ill do it myself. at the moment those cams will be saying in.

i might have a crack at the comp ratio myself id say its a fair bit lower that most engines built and needs higher boost lol not 18 psi im running now, danny had it to 250 awkw so far with out a new tune... should be sweet at 25psi ah ha ha ha ha

[kiahatsiu]

e85 and boost; problem solved.
Failing that, I hear 1gz-ge V12s will fit in with relative ease. Use the AWD celcior gearbag and you are away.

[dr20t]

e85 and boost; problem solved.
Failing that, I hear 1gz-ge V12s will fit in with relative ease. Use the AWD celcior gearbag and you are away.

All well and good to throw more boost into it but if the air and fuel mixture can't atomise correctly due to a very low dynamic compression ratio then you will always have problems.

If they ordered pistons for a static compression of 8:1 or under, with that sort of cam overlap (very rough calculation and assuming a 50cc combustion chamber, you're dynamic compression will be sitting just over around 5:1. That's ridiculously low and will cause all sorts of erratic correction problems for a stock ecu. Unless your idle is at 1800rpm or so like a rotor!

One other thing that might help is switching off closed loop, so it's constantly reading open and not trying to correct afr to target? This might help flatten the erratic idle and lean out conditions from the massive overlap of the cams.

The mismatched inlet and exh cams arent so much of a problem as long as this was thought out when selecting. The biggest problem is the separation between inlet and exhaust, over 20 degrees, which in simple terms means your exh valve is open for a long time before inlet closes. This is great for venturi effect as long as the resultant remaining mixture is compressed enough to cause a big bang. However with that much overlap you would hope for static compression of about 9.2:1 to get the best off boost response and ve up top.

Please don't take this as gospel I'm just throwing some rough numbers in here

I'm not meaning to rub salt into the wound here but mrt have a lot to answer for here man

Mick

[<GB>]

the car was in constant open look when danny first got it, rev zone left it like that, probably to mask some of the running issues

[Kekotic]

the car was in constant open look when danny first got it, rev zone left it like that, probably to mask some of the running issues

So after you and Bruces experiences with Revzone, can we officially put them on a list of places not to go for tuning now?

Hope things get sorted with your car, you sound a little more hopeful now than a few weeks ago?

[<GB>]

the car was in constant open look when danny first got it, rev zone left it like that, probably to mask some of the running issues

So after you and Bruces experiences with Revzone, can we officially put them on a list of places not to go for tuning now?

Hope things get sorted with your car, you sound a little more hopeful now than a few weeks ago?

well im not sure they can do our style ecu's but other stuff they might be fine

[dr20t]

I just re-read the cam specs - I stuffed up I thought you said 268 degree exh cam not 258 like I thought

So the above calcs are wrong. And there's nothing wrong with a difference like that in inlet and exh cams at all. In fact for our ej's the tried and true are the bigger inlet an smaller exh cams.

However like you said they suck balls for mixing a 2 & 2.5 set of cams the monkeys

Hope its getting closer to fixed gb

Mick

[<GB>]

I just re-read the cam specs - I stuffed up I thought you said 268 degree exh cam not 258 like I thought

So the above calcs are wrong. And there's nothing wrong with a difference like that in inlet and exh cams at all. In fact for our ej's the tried and true are the bigger inlet an smaller exh cams.

However like you said they suck balls for mixing a 2 & 2.5 set of cams the monkeys

Hope its getting closer to fixed gb

Mick

yeah, sucks balls

i got an email from crosworth US and they said they couldnt have sold these cams and put me onto their UK division

[<GB>]

Small updates with still no good news on it lol


Crosworth
Intake
20004723
Ej25 Sti
277/11

crosworth
Exhaust
20004725
Ej20 wrx
268/10.2

i recived this today from crosworth....

im not sure why my exhaust nummbers dont match up the one they have listed...


Thank you for your email.

If you have the camshafts 20004723 (Intake) and 20004725 (Exhaust), it means you have the KK3766 camshaft set.

It is a camshaft set for single AVCS Subaru engine with Electronic throttle or what we call US type camshaft sensor triggers.

These camshafts are designed for Subaru Impreza with EJ25 with single AVCS.

I attached the information card to this email for your information.

Is your car single AVCS or Dual AVCS?


You pointed your car was a 2008 Liberty. We have limited experience with Liberty/Legacy.

We currently have 2 types of Single AVCS camshafts in our catalogue KK3766 and KK3920. The difference is in the camshaft triggers as you can see in the picture below.



The one on the left is for “North American” spec single AVCS engines with Electronic throttle.
The one on the right is for “JDM/Euro” spec single AVCS engines.

Basically, in the late production of single AVCS engines, some of the Euro/JDM cars were fitted with US type cam triggers and sensors.

The difference between these is the triggers shape and the camshaft sensor position.

[bigBADbenny]

Quote>>> KK3766 Application: Subaru STi EJ25 Engines - Stage 2 278/274
Stage 2 - This is Cosworth's more agressive cam. It is a 278/274 cam that will shift the powerband up higher than the S1 cam, making it ideal for larger sized turbos like the Garret GT35R and larger. It has a slightly noticable lope at idle, but does not sacrifice drivability.<<<Quote

ideal for larger sized turbos like the Garret GT35R and larger

[<GB>]

Quote>>> KK3766 Application: Subaru STi EJ25 Engines - Stage 2 278/274
Stage 2 - This is Cosworth's more agressive cam. It is a 278/274 cam that will shift the powerband up higher than the S1 cam, making it ideal for larger sized turbos like the Garret GT35R and larger. It has a slightly noticable lope at idle, but does not sacrifice drivability.<<<Quote

ideal for larger sized turbos like the Garret GT35R and larger

But the numbers on my cam are slightly different to those ones,

Did u get that info off their site?

[bigBADbenny]

http://tinyurl.com/7jzk7my via http://tinyurl.com/749dchx