Head gasket? WTF

[Missileman]

2 hours ago, Slap said:

If it isnt the leak in the zorst mani gasket doing it maybe just maybe it's clean from unburnt fuel from missfires or leaky injectors.

naa

[admS15]

No miss fires or leaky injectors. I pressurised the rail when I pulled it out but rest assured the injectors will be sent for a clean and flow check and missile man a new set of manifold studs has been ordered. Don't want to have to touch anything for a long time.

Overnight parts from eBay

[admS15]

When pulling everything apart, i noticed the exhaust cam out by 1 tooth to the right. Whoever put the timing belt on 7 years ago set it like that.



My question is, should i set it up like that considering the tune has been done with the cam in that position?

Is that 1 tooth advanced or retarded and what effect is it having on the power curve?

Thanks gents.

[Dose Pipe Sutututu]

Might have been done on purpose to aid low down power, a bit ghetto OR it was installed incorrectly lol.

You'll find your AFRs might change too as altering the cam timing and or cam duration/lift affects the engines VE.

Setting it back to 0 should end up giving you a bit more top end

 

[Ben C34]

That's advanced.

Normally you would advance the inlet and retard the exhaust. So that is weird. I would be putting it back to zero for sure.

 

[admS15]

So if i set back to zero, this will effect base timing,then I'll need to check with timing light and set back to 15° or no?

 

Funny thing though, the cas looked pretty centred the way everything was.

 

I read quite a few threads last night where guys have found the same thing. 1 set it back to zero and apparently his car ran like crap. Tempted to leave it as is and not create headaches but then again i want to do everything right.

 

f**k, what to do..

 

 

 

[Dose Pipe Sutututu]

Set it to 0, re-time the motor and back on the dyno for quick squirt, car should make a bit more power up top.

Regarding exhaust cam years generally give you more top end, so in your case going from an advance back to where it should be is essentially retarding the exhaust.

[GTSBoy]

The smart thing to do is to put a degree wheel & pointer on the crank pulley, take off the cam covers so you can see what the lobes are doing (and perhaps mount a dial gauge to actually measure the valve events) and then see what's happening with the engine as it is currently assembled.  You never know, the exhaust cam could be a dodgy grind, and the tooth was a crude correction.  Or it could have just been a clumsy f**k when the belt was last changed.  Either way, knowledge is power.

[iruvyouskyrine]

If i was you as the head is getting a decent birthday i would set it back to zero, (obviously) check your base timing, and go and get a touch up tune done. Probably some more power to be picked up and you can sleep well knowing everything is all sweet. Touch up tune should only be somewhere between $200-400 i would imagine depending on tuner and if you want multi-fuel.

[Slap]

Advance exahust cam gear will aid boost spool up rate and midrange snapiness.
Loose some low end.
If its tuned that way leave it.

There is no normaly for cam gears.

N/a cars- advance in - ex retard
Boosted cars -retard in - advance ex

Its silly to tune boosted cars like an n/a car unless you want shit top end a touchy off boost low rpm low torque rev. About the only gains will be low rpm on boost.

[Ben C34]

5 minutes ago, Slap said:

Advance exahust cam gear will aid boost spool up rate and midrange snapiness.
Loose some low end.
If its tuned that way leave it.

There is no normaly for cam gears.

N/a cars- advance in - ex retard
Boosted cars -retard in - advance ex

Its silly to tune boosted cars like an n/a car unless you want shit top end a touchy off boost low rpm low torque rev. About the only gains will be low rpm on boost.

You are the only one eve lr to recComend that.

As for the retard inlet bit in particular that makes no sense as people with rb26 spend heaps of cash to get vct to advance the intake cam to improve boost response. 

Do you have any examples of your theory?

 

[Slap]

You are the only one eve lr to recComend that.
As for the retard inlet bit in particular that makes no sense as people with rb26 spend heaps of cash to get vct to advance the intake cam to improve boost response. 
Do you have any examples of your theory?
 

They may but not all rbs have vct and it wont aid boost anything like the setup i described.
Do some research ben!

[Slap]

https://www.hpacademy.com/forum/general-tuning-discussion/show/cam-gear-adjustments

https://www.hamotorsports.com/cam-gear-tuning.html


For people that want more info!
Or truth

[admS15]

.

[Ben C34]

1 hour ago, Slap said:

https://www.hpacademy.com/forum/general-tuning-discussion/show/cam-gear-adjustments

https://www.hamotorsports.com/cam-gear-tuning.html


For people that want more info!
Or truth

So the hp a ademy thread basically confirms advancing the intake cam improves low to mid, and the ha motorsport info I reject!

[Ben C34]

https://www.enginelabs.com/news/spooling-up-tuning-dohc-variable-valve-timing-for-boost/

[admS15]

So basically my exhaust cam is advanced roughly 7 degrees, apparently thats how much 1 tooth is and that should aid spool and low end power and torque. My car doesn't really fit this picture.

Most cars with my setup, hf turbo e85 etc make around 200kw at 4000rpm and max torque around 4.5k rpm. Peak power 300-320kw.Mine only makes around 150kw at 4k rpm and is lazy with low end torque, peak torque comes in around 5k + but does get to the peak kw figure, makes 312.

So that much advance is either too much and having a negative effect or there is something else in my setup holding it back down low.

I dont want to lose anything down low as that's what id really like to improve but i will set the timing back to zero as per factory and see how it feels. If it runs like crap or gives me the shits in any way, I'll just put it back to how it was considering the car has been running pretty good and is fast enough as it is really.

Gtsboy's suggestion of degreeing everything is probably the way to go and leaves no question unanswered but unfortunately i dont have the patience and required tools to do it.

[GTSBoy]

13 minutes ago, admS15 said:

Gtsboy's suggestion of degreeing everything is probably the way to go and leaves no question unanswered but unfortunately i dont have the patience and required tools to do it.

There are times when taking it to a workshop that has that stuff is worth the investment. In my case it's easier and cheaper because brother-in-law, but I'd still do it regardless.

[admS15]

There are times when taking it to a workshop that has that stuff is worth the investment. In my case it's easier and cheaper because brother-in-law, but I'd still do it regardless.

I have a cousin who is an engine builder but unfortunately he moved overseas a few years ago[emoji26]

[Slap]

https://www.enginelabs.com/news/spooling-up-tuning-dohc-variable-valve-timing-for-boost/

Thanks for the confirmation ben. He even states "that it is POSSIBLE to tune a NEWER turbo using VCT like you would a NATURALLY ASSPIRATED car."


AdamS15
Probably the spark timming holding ya back being e85 or air intake or fuel delivery (TUNE).
Advance ex will make off boost low rpm very sad but power up hard as boost spools.
I have set my car up both ways with a 33hiflo turbo and even though advance in and retard ex greatly improves off boost performance and give great slack slow driveability for street it is worth trashing the perk for the hit of boost and high mid range gains.

Stock rb20det has like 150+kw.
Have you been driving beefier cars latley?
My 6lt (240+kw)makes my rb feel wussy af down low but the rb makes up for it with boost hit.