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Just got off the phone to Andy & he has tuned 2 r33 this week with basically they same mods & they were in 180rwkw bracket! The only difference is that the were running 95ron! so the 98ron stuff aint looking to good!

The first tank of 98 I ran in the GTR I had to pull a couple of degrees out of it because it was pinging a bit so.... could be.

I'm assuming that Kutzie is tuning the thing to the point just before detonation. And that the detonation is the limmiting factor for your combination.

It's obviously not the dyno, I doubt it would be Kutzie's operation. That leaves ur car...

I could be a lot of different things.

It could quite possibly have a higher static comp ratio. Or silly things like a dodgy injector, a wrong set of spark plugs (often the tips heat up to a point where they induce detonation), a broken or damaged spark plug.

If it's been re-built, dose it have a DET head? Has somone f**ked around with the combustion chambers or ports?? You could be getting hot spots at the point of combustion.

Do you have an unknown blockage in ur exhaust system (stuffed cat or muffler can cause so much back preassure in the housing, heats up the exhaust valvesw and induces detonation), intake or charge pipes.

Do you still have a stock crank case breather set up? It's not uncommon for a rebuit engine to breath a little heavier (depending on the way the builder set gaps and clearances) and if you have those lines going back into ur intake that can induce detonation. Maybe get urself an oil air seperator or catch can.

It could be lots of things......

OR

You just got a dodgy tank of fuel. I can vouch for the fresh tank at BP in Kingston atm.

Oh by the way. If you do take it to another dyno and the operator dosn't have a super keen ear or a Knock Box (Head Phones and amplifier to listen for pre-detonation)... with ur car, wich is super prone to detonation... You might be building urself another motor.

Plus, if u do get a higher reading on another dyno, it still dosn't mean you have more power.

If I had ur problem, I'd replace my plugs, use a very good oil and filter, drop my exhaust and check the cat, take my pipe work apart and have a look, run another tank of 98 through it then take it back, strap it down and see what happens... you'll know quite quickly if it'll make more power.

Sory about the long post.

As far as i know about the rebuild dav griffith put in the following:

forged piston set 20tho

gtr rods

arp conrod bolt set

race series main bearing set

bigend bearing set

nissan gaskets

nissan cam belt

basically the rebuild was ment to be achieve basically standard spec with just them parts setup to achieve that!

yes it still has the DET head on it!

yes kutzie did tune it to the point just before detonation, but backed off abit!

exhaust is fine less than 3months old!

im not gonna bother taking it to anyone else cause kutzie know's his shit!

he said for starter run some 95ron through is and get it back on the dyno & that will bascailly tell me weather its the fuel or my motor!

Cheers

Al

  • 2 weeks later...

This should be an interesting test then, as my new RB25 is being tuned in Melbourne at the moment on 98ron. To see if there is any difference in the 98ron fuel that comes over base straight, And also the power difference! Dyno to Dyno as there is about 15 cars in Hobart that have also been tuned by this dyno that is in Melbourne as well. (Sam Cornell’s)

Once I have run a couple of 98ron tanks through it in Hobart, I will take my car to Pro and see kutzie and check it on his dyno

I do think it could be your motor by the sounds of things and as XRATED has said go through every thing and check it.

I know of at least 30+ people running BP 98ron in Hobart and none of them have hade any problems at all.

Yer i think the fuel is good! & the Problem with my power output is that my turbo is about to shit its self! Took a temp reading off one of the pipe's that comes of the turbo & it was 95' degree's @ full noise. plus it wont hold anymore than .7bar it keeps dropping back & that with an AVCR. So im goin to do Turbo & 555cc Nismo Injectors. And then let Andy have another go!

What turbo's are people running? any suggestions? I was thinking of this one:

Spec as follows: GT30R

Bolt on GTS-T Turbine Housing 0.70a/r Internal Gate

Turbine Wheel = 84trim

GT Ball Beareing Garrett Core

Comp Wheel = 56trim, 57mm Inducer

Comp Housing = 0.60a/r Approx HP = 450hp Flywheel

Alan

Edited by al_r33
This should be an interesting test then, as my new RB25 is being tuned in Melbourne at the moment on 98ron. To see if there is any difference in the 98ron fuel that comes over base straight, And also the power difference! Dyno to Dyno as there is about 15 cars in Hobart that have also been tuned by this dyno that is in Melbourne as well. (Sam Cornell’s)

Once I have run a couple of 98ron tanks through it in Hobart, I will take my car to Pro and see kutzie and check it on his dyno

Sounds like a fairly pointless comparison to me; no two dynos and no two dyno runs are exactly the same, IMHO the only before and after testing worth even using as an advisory figure is done on one dyno and one only.

Anyway, 138rwkw is very average. My 17 year old redtop RB20, with a high rpm misfire and 10psi boost, stock except for a 3" cat back squeaked out 116rwkw. For an RB25DET to make 138rwkw with a rebuild and your mods something has to be seriously not right. Even a REALLY low reading dyno wouldn't account for that, IMO.

Sounds like a fairly pointless comparison to me; no two dynos and no two dyno runs are exactly the same, IMHO the only before and after testing worth even using as an advisory figure is done on one dyno and one only.

Anyway, 138rwkw is very average. My 17 year old redtop RB20, with a high rpm misfire and 10psi boost, stock except for a 3" cat back squeaked out 116rwkw. For an RB25DET to make 138rwkw with a rebuild and your mods something has to be seriously not right. Even a REALLY low reading dyno wouldn't account for that, IMO.

No sh!t no two dynos are the same every one nows that,

Mainly just to check to make shore the fuel is ok!

  • 2 weeks later...

Alan....

Ive just read all about your problem...WOW

With what you seem to have done to your engine and all the right mods by now you should be putting out towards the 200 mark

Dont bite my head of for asking but is your R33 a Automatic...

Alan....

Ive just read all about your problem...WOW

With what you seem to have done to your engine and all the right mods by now you should be putting out towards the 200 mark

Dont bite my head of for asking but is your R33 a Automatic...

yeah Al's car is manual and im pretty sure he has narrowed it down to a dicky turbo.

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