Jump to content
SAU Community

Recommended Posts

the gears can always let you unlock the best of what you have got, shifting the powerband just enough to make it what you were after.

you wont need to change the belt when you change the gears though. Just put the motor to TDC on 1 and draw a mark on the belt where the mating marks sit on the gears. the new gears will have the mating mark in the same spot.

I think just line everything up at TDC and reference the std markings in the block and timing backing plate etc. Belts can skip a tooth and flop around the crank pulley and when you tensio it back up be a way off where the old markings were. Best go on the block markings and not care about the belt

that's the right way to do it, yet I detected OP did not want to pull lower timing case off as its the majority of the task in changing the belt (done 10ks ago).

in which case you can be dodgey and do it the other way.

myself id do it properly. just sayin'

Ok, So have wasted time and money thinking about the RB25 and 20G setup and leaning on it for all its worth. I want to be sure that walking away from what has been a champion turbo is the right thing to do. Also will give a good baseline for other setups being trialled

So by the end of the day will be interesting to compare:

RB20 RB25

TD06-20G. 8cm 12cm

Cams Std 256/8.5 Tomei

Fuel E85 E85

Both engines run the same inlet and exhaust manifolds. As it is an R32 RB25 it does not have NVCS will be interesting if the better breathing hot side, bigger cams and bigger engine will result in more power then I was making on the RB20

Figured I'd do an update on my setup.

old-return-flow-intercooler-kit-RB25.jpg

I made 235kw on 18psi, RB25 TD06 20G 10cm.

All you cool cats worked out my intercooler was shit house, you were all right!

I've stuck to return flow as I want it the engine bay as factory looking as possible, but a much better setup.


HKS-type-S-intercooler-kit-installed.jpg


Ended up taking it for a drive on Monday, left the boost controller on low just to be safe. Low boost was set at 14psi previously, and with the new intercooler it's pumping out 20psi! Crazy how much restriction the old cooler setup made. Pulls like a freight train now too which is great. Also feels less laggy too, win win win!

So thank you for all your input lads :D

Edited by Run-It-Hard

I will need to get it on a dyno soon, needs rego first though (ran out lol).


I ended up finding a HKS type S intercooler kit in Japan and got it sent over. Neat bit of kit, managed to get the return up nice and high too with a bit of moding so I'm all smiles :D

by the end of the day will be interesting to compare:

RB20 RB25

TD06-20G. 8cm 12cm

Cams Std 256/8.5 Tomei

Fuel E85 E85

Both engines run the same inlet and exhaust manifolds. As it is an R32 RB25 it does not have NVCS will be interesting if the better breathing hot side, bigger cams and bigger engine will result in more power then I was making on the RB20

I'll take a punt and say that the 25 won't wake up down low with the bigger housing, but should shade the 20 between 4-7000. Will be an interesting comparison.

8cm and you reckon it was lazy down low?!

Do you think that's because the turbine was choking at the lower shaft speeds (in that tiny housing) or a different reason?


A 20G shouldnt be lazy down low, especially with an 8cm hey..

I had a 12cm on mine for a month, was so bad lol.


TD06-12cm-tune-RB25-dyno-sheet.jpg

Although it could have had better response with my new cooler setup. Cams might help it out too, dunno. Trent's set it plenty of times that he loved his, he had cams too.

▲ id have to agree! mine had an 8cm rear on rb25 and was way lazy down low..12cm i think will make it more doughy and i dont think up top with that much of an advantage

LOL...really? Something very different between our setups then. I was hitting 18psi at 3,200rpm or something stupid and show was over with the thing losing its pull over 6,500rpm. It was mega grunty with the 8cm housing. And that was with cams at 0 and only a 2/3 tune.

I like the way the 12cm drives but on a very rough tune with no ignition the 12cm housing has generally added 800-1,000rpm to response. Would be far easier and nicer to drive with the way it delivers its power.

Will see if we get any of theloss in response back with the changes we made today....the car got pulled off the dyno due to another car needing some urgent work.

Will keep looking for a 10cm housing but think the T67 will go on before a find the right sized housing for the 20G. That will be the real test as I am pretty sure we have maxed out the compressor on the 20G so the question is will the billet wheel flow more with the TD06-12cm vs the T67-25G 10cm . That will be the real interesting test. Smaller, lower flowing turbine with a 78mm cast compressor wheel VS a larger higher flowing turbine with a lighter, smaller billet 73mm compressor with the larger 12cm housing.

I would go straight for the proven 10cm if I had one so ...no other choice then to waste tuners dyno time with my games :)

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

    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
×
×
  • Create New...