Rb20 Suspected Timing Issue

[Nightslug]

hi all,

I have a suspected timing issue on my rb20det

basicly its not making the power it should be and is over all down on power

mods are

20det motor 112.00kms reasonble low kms keept in good condition

25det turbo good conditiion

dsr uprated coils

370cc ca18det injectors all flow test pre install

walbro 255lph fuel pump

FMIC kit

link g4 gts plug in to controll everything.

everythings been check over to made sure its all in check

arfter a full complete tune its only just making 170kw at its very peak(13.5psi) my previous power before the ecu was 155kw

my tunner said its knock limited when tunning upwards of 170kw and possible that the timming belt is out one tooth casing the motor to basicly not make the power it should be making with thses mods (190 to 200kw) all tunning was done on a hub dyno

im drawn away from it being the turbo as its dosent blow and smoke what so ever and holds boost all the way up the rev range

your thoughts? if i take the cambelt cover off is there any simple way i can confirm that its out one tooth? looking at marking etc?

thanks

[Moodles2]

rb20 making 190-200kw with those mods and a stock rb25 turbo, to me sounds alittle far fetched. 13.5psi doesn't exactly sound safe for a stock rb25 (unless it's had a steel wheel put in).

I would have thought if it was out by 1 tooth it would run like utter crap that it would be noticable though.

As for timing belt alignment, I know it's from the RB26 manual, but the only thing that will really be different is the timing cover: http://rbforums.org/pdfs/r32rb26timingbelt.pdf

[Nightslug]

rb20 making 190-200kw with those mods and a stock rb25 turbo, to me sounds alittle far fetched. 13.5psi doesn't exactly sound safe for a stock rb25 (unless it's had a steel wheel put in).

I would have thought if it was out by 1 tooth it would run like utter crap that it would be noticable though.

As for timing belt alignment, I know it's from the RB26 manual, but the only thing that will really be different is the timing cover: http://rbforums.org/pdfs/r32rb26timingbelt.pdf

Yeah those were the power figures qouted by my tunner atleast 180 to 190kw id say anywho,

its only putting down around 160ish kw at the moment as he tunned it back to 12psi...

[t_revz]

hi all,

I have a suspected timing issue on my rb20det

basicly its not making the power it should be and is over all down on power

mods are

20det motor 112.00kms reasonble low kms keept in good condition

25det turbo good conditiion

dsr uprated coils

370cc ca18det injectors all flow test pre install

walbro 255lph fuel pump

FMIC kit

link g4 gts plug in to controll everything.

everythings been check over to made sure its all in check

arfter a full complete tune its only just making 170kw at its very peak(13.5psi) my previous power before the ecu was 155kw

my tunner said its knock limited when tunning upwards of 170kw and possible that the timming belt is out one tooth casing the motor to basicly not make the power it should be making with thses mods (190 to 200kw) all tunning was done on a hub dyno

im drawn away from it being the turbo as its dosent blow and smoke what so ever and holds boost all the way up the rev range

your thoughts? if i take the cambelt cover off is there any simple way i can confirm that its out one tooth? looking at marking etc?

thanks

does that mean between 155 and 170 was only ecu?

i think you`ll find a stock rb25 with stock turbo and same boost FMIC etc will only be around 200ish

[t_revz]

hi all,

I have a suspected timing issue on my rb20det

basicly its not making the power it should be and is over all down on power

mods are

20det motor 112.00kms reasonble low kms keept in good condition

25det turbo good conditiion

dsr uprated coils

370cc ca18det injectors all flow test pre install

walbro 255lph fuel pump

FMIC kit

link g4 gts plug in to controll everything.

everythings been check over to made sure its all in check

arfter a full complete tune its only just making 170kw at its very peak(13.5psi) my previous power before the ecu was 155kw

my tunner said its knock limited when tunning upwards of 170kw and possible that the timming belt is out one tooth casing the motor to basicly not make the power it should be making with thses mods (190 to 200kw) all tunning was done on a hub dyno

im drawn away from it being the turbo as its dosent blow and smoke what so ever and holds boost all the way up the rev range

your thoughts? if i take the cambelt cover off is there any simple way i can confirm that its out one tooth? looking at marking etc?

thanks

does that mean between 155 and 170 was only ecu?

i th

[Rolls]

So you've upgraded the turbo from the rb20 one to a 25 and with a tune you have gone from 155 to 170kw? Sounds bang on to me, what is the issue?

Power is around the norm, most people with rb25dets don't even make 200kw on that boost, you've got half a litre extra and you expect to make the same?

If the timing was off by one tooth you'd be making 120kw and it would run like crap, I really don't think there is any issue here you are just expecting more than is the norm. What does your tuner mean it is knock limited, as in it is getting high knock readings? if that is the case then you have an issue somewhere else, was he having fueling issues? What kind of afrs are you running? High egts can cause it as well, is it possible your cat shit itself? Drop the exhaust and see what power is like.

Edited September 27, 2010 by Rolls

[JonnoHR31]

pull timing cover off and line the marks up, if they dont line up then its out, simple.

200rwkw is possible with some cars but not all will make that power, even on a hub dyno. 170 is a little below average but still fairly normal for the mods

[Lithium]

basicly its not making the power it should be and is over all down on power

your thoughts? if i take the cambelt cover off is there any simple way i can confirm that its out one tooth? looking at marking etc?

You have a GTS4, eh? Who tuned it, I am guessing Aaron? Has he ever tuned an R32 GTS4 before?

One of my mates had similar issues trying to get power out of his GTS4 years ago on a steel wheeled VG30 turbo, he tried running more boost than you are (peaking at like 19psi) and all sorts and never went north of 190kw. Even in RWD mode the ATTESA setup seems to drain the poor wee RB20

[Nightslug]

So you've upgraded the turbo from the rb20 one to a 25 and with a tune you have gone from 155 to 170kw? Sounds bang on to me, what is the issue?

Power is around the norm, most people with rb25dets don't even make 200kw on that boost, you've got half a litre extra and you expect to make the same?

If the timing was off by one tooth you'd be making 120kw and it would run like crap, I really don't think there is any issue here you are just expecting more than is the norm. What does your tuner mean it is knock limited, as in it is getting high knock readings? if that is the case then you have an issue somewhere else, was he having fueling issues? What kind of afrs are you running? High egts can cause it as well, is it possible your cat shit itself? Drop the exhaust and see what power is like.

New zealanders dont run cats.

Its running safe as in terms of being lean or rich

Long story short it made 155kws with stock ecu, then i added a link g4 and larger injectors to keep up with the blower and it made just over 10kws more 165 170kw

he told me the moter allmost seemed to respond like a non turbo rb20de higher compression motor.

[Lithium]

Hi man, do you have a dyno plot you can share?

I actually tuned a mates GTSt (Looney_head off SDU) last weekend which is running a VG30 turbo and I was quite interested to see how that'd go, partly thinking about your results. We ended up with about 201rwkw on MacLennan's dyno from a 149kw starting point so yeah, quite different results.

Have you looked into sorting out the cam timing?