Rb20de Itb Build

[Superior Auto Parts]

ITB just like an M3 lol.

From my experiance with NA. ITB will let the car breath a lot better but you can stop there. How far are you going, are you doing cams exhaust computer?

Results will be interesting

I would love to see the head built to raise your redline up^^

[Slide]

He is already running a Link and i believe he has said that cams have been ground to match the ITB's.

[BADR33]

i recken you need to bump up the compression more, run a e30 fuel.

im not sure if the rally side of motorsport is allowed to run ethenol fuel yet. i know its been approved for general motorsport use.

although you then possibly want to play around more with your extractors and look at throttle postion ajustable trumpets. and some form of a ducted cold air box. im still waiting for you to come down to wellington with your crazy setup.

the link has the ability to be tuned via tps for setups like this, the newer g4 link is even better with sequencial injecton. on turbo cars it has 4d mapping, so you can tune it to make full boost on 20% throttle if you wanted.

[screamin']

Hey Geoff, I was halfway to Welly yesterday racing in forestry north of Taupo. Looks like I was 2nd 2WD so I'm happy with that.

The car is running a G4 Link, planed and ported head, cams with adjustable gears. The motor is going pretty strong at the moment, but there is more in it yet. We're doing away with the brake booster soon so I can run bigger trumpets so we can dial in more duration on the cams and get rid of the reverberation out the intake.

I run it on 98 cause it's easy to get from any BP and stick to that. We've changed the exhaust a few times and the current system seems to be the goods.

The G4 is tuned just off the tps at the mo, because we can't get enough vacuum off the itb's with the cam overlap.

It's something different and turns heads wherever I race it. Surprises a few the fact that we've got it working so good on the gravel.

[NZM.031]

ITB's and big cams FTW! or just run a set of webers... yeh baby!

[BADR33]

shane i was talking to a guy that builds quite a few race engines, you may of heard of him, mark maholland.

and the topic of itbs on na came up,

he was telling me about how he built for some race car, i can't rember now, it was ajustiable trumpets with vacume operated valves,

so say if you planted boot the trumpt, chamber drops right down, as soon as you back off it snaps backup.

not the easyest system to explain.

apparantly a couple years later they started using it on f1 cars.

he was also telling me that if you spent a bit of time developing the intake system you could actually build boost, yes boost with out a turbo. its all to do with capturing the sound waves and getting it to go all towards the trumpets at the right time.

it was a rather interesting conversation i must say, brought up some rather interesting ideas. all bought up by the suzuki g13b offroad racer we were tuning for the taupo 1000km race.

good to hear its all running well and your doing well, good to see you also got a g4 link, there an awesome piece of gear.

[Lithium]

he was also telling me that if you spent a bit of time developing the intake system you could actually build boost, yes boost with out a turbo. its all to do with capturing the sound waves and getting it to go all towards the trumpets at the right time.

it was a rather interesting conversation i must say, brought up some rather interesting ideas

Helmholtz resonance tuning shouldn't be a new idea really for anyone exploring using ITBs or any serious NA tuning really, the whole idea behind going to ITBs is to redefine the intake runner resonance and use that to maximise throttle response and torque across the utilised rev range. Such tuning is also what good exhaust design is all about :-)

[screamin']

Yeah I've heard of Mark. I'm quite lucky really, my Dad builds race motors, from rotary's to chevs and now an RB, been doing it for about 30 - 40 years now.

Variable length intakes would be ideal, but I'm not going down that track. 100% perfect tune at every throttle percentage isn't required on a loose surface like gravel, plus it's just another thing to go wrong. Part of what we are doing with the new trumpet design will effectively create boost, but I'm not plumbing in an intercooler just yet!

Right on the money there Lithium.

[bomb3r]

Hey man, this is throughly impressive, thanks for sharing the info and progress