Jump to content
SAU Community

Recommended Posts

Every head should be CC'd if you dont knows it's history.

I know mine had the face machined prior to me buying it and again was faced after the front water gallery was tigged up.

My R33 RB25DET head's bowls averaged at 58.7 CCs . It's time consuming to get the bowls volume close to each other (0.2CC +/-). :)

no. 6 cyl had the largest bowl volume: 59.8CCs. Had to remove a bit of material to clean up the pitting left from detonation.

PS: I used a burette to measure the bowls.

Edited by Alf
Problem solved.

Looks like the cat or middle muffler has collapsed and blocked most of the exhaust.

Got it to 1 bar after I dropped the exhaust at the dump pipe flange and went for a blat up the street.

Whoo hoo, now to just replace the cat or muffler and back to the dyno.

Think Ill have a few beers tonight.

Hope those beers were good.

I should have thought of that. I had a cat collapse once and it was doing similar, but seems fairly uncommon. Well done.

the greddy copy manifolds have been discussed in the froced inuction forum, the casting quality seems to be poor, and you can get them off ebay for about $200, noone has got dyno proof yet if they work. I think the siemens injectors are all top feed, so unless you get an r34 fuel rail, which fits the greddy copy manifold, they wont fit. Even with the rail, im not sure if the siemens are the same dimensions as the r34 gtt injectors

Ohhh ok.

I just thought they had smaller housings than a GT35 or are they the same but with smaller wheels?

Do a search for the results of R31Nismoid...its his old turbo that you are talking about.

Also, another quetion... those of you running RB25 heads vs Rb26. IS there a measurable difference between the results are ppl getting with the same turbos...main variable being head and inlet plenum?

Not sure if i should bother with an RB26 head or not

Do a search for the results of R31Nismoid...its his old turbo that you are talking about.

Also, another quetion... those of you running RB25 heads vs Rb26. IS there a measurable difference between the results are ppl getting with the same turbos...main variable being head and inlet plenum?

Not sure if i should bother with an RB26 head or not

Forget about whether or not the RB26 head itself is "better", the fact is it will work out cheaper when you add it all up. Inlet manifold, multiple throttle bodies, plenum, top feed injectors, cams, solid followers, no VVT, adj camshaft pulleys, valves, valves springs etc etc. They are what makes an RB26 head the ONLY way to go.

:P cheers ;)

I cut the cat out of my exhaust today - it is completely screwed and deformed internally. If you hold it up to the light you can not see any daylight.

In the end I couldnt even get the car to idle there was that much back pressure.

It is approx 2500 kms old - I am currently in discussions with regards to a warranty claim so dont want to mention any names as yet. It was not a cheap item though.

yeah - that gets a little expensive when you get defected and they decide to take a closer look - I did consider it though.

Custom Exhaust Specialists in Bris are doing me a 3.5 inch custom cat they have XR6 turbos making 700-750 flywheel horsepower with - its cheaper than the 10k fine :-)

time to put a "hi flow" one in then? :P

i need to scan it this weekend but i ran outta fuel so i need to do more work on the dyno after i change the pump.

How is a good way to get out of the fuel problem? i want to get over 400rwkw if i can with the stock head.

peek power was at around 160ks an hour in 4th gear.. i need to bring it down a bit but wont worry about that untill i get the fuel pump situation fixed up.

Full Boost comes on - 110ks an hour (20psi) in 4th gear all the way up to the end 20psi

It even has 5psi of boost at 92ks an hour in 4th.. comes on early i wreckon

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • You will now be able to lift the parcel shelf trim enough to get to the shock cover bolts; if you need to full remove the parcel shelf trim for some reason you also remove the escutcheons around the rear seat release and you will have to unplug the high stop light wiring from the boot. Next up is removal of the bracket; 6 nuts and a bolt Good news, you've finally got to the strut top! Remove the dust cover and the 3 shock mount nuts (perhaps leave 1 on lightly for now....) Same on the other side, but easier now you've done it all before
    • OK, so a bunch of trim needs to come off to get to the rear shock top mounts. Once the seat is out of the way, the plastic trim needs to come off. Remove 2 clips at the top then slide the trim towards the centre of the car to clear the lower clip Next you need to be able to lift the parcel shelf, which means you need to remove the mid dark trim around the door, and then the upper light trim above the parcel shelf. The mid trim has a clip in the middle to remove first, then lift the lowest trim off the top of the mid trim (unclips). At the top there is a hidden clip on the inner side to release first by pulling inwards, then the main clip releases by pulling the top towards the front of the car. The door seal comes off with the trim, just put them aside. The the lighter upper trim, this is easy to break to top clips so take it carefully. There is a hidden clip towards the bottom and another in the middle to release first by pulling inwards. Once they are out, there are 3 clips along the rear windscreen side of the panel that are hard to get under. This is what the rear of the panel looks like to assist:
    • Yes. Autos typically work from the speed sensor on the pinion shaft of the diff. I also think that even if you have a proper speed sensor for the bog manual in the manual box, that the signal it outputs is not compatible with the auto dash anyway. You should consult that manual (the book, not the gearbox).
    • And I just realised that that advice is slightly nonsensical for a GTR, because you need 2 of them. But it is otherwise true.
    • Having had a reasonable look at the car, I'll be able to remove the (one time) rams and retract the hinge (they are held in the down location by a tiny (m3?) sacrificial screw) which will get it physically back in shape. From there if you remove the rams you need a resistor to turn off the airbag light (as Mark said, there are plug in kits and I might go that way because its reversible). And...per all the threads on here, even if you have the resistors to turn off the airbag light, the bonnet light will stay on as it writes to the airbag computer history - that is either replace the airbag controller, reprogam the EPROM (if I can work out how), or remove the globe from the dash. Having seen how sensitive this system is, if I had my time over I'd pre-emptively remove the rams, even on a road car, because this is all a very unnecessary pain in the arse. Reminds me, time to go and have a look at the Fuga too....
×
×
  • Create New...