screamin'

Sounds like fun! If you are really keen, consider some side draft Webbers or independent throttle bodies. I run itb's and some big cams, and oh the sound! More mild cams and itb's would be great street cred emitting sound from an early Zed. The Neo has the right turning mass for rev's, so I'm keen to see what it will pull if my old RB20DE managed 8,600rpm for six years of rallying. With a car as light as a 280 I would just look at taking some off the head, induction and exhaust mods, a tune and see how it goes. From there decide if you want to part with a lot more cash for a little more gain.

I'm building one of these for competition use at the moment, to replace my previous R32 RB20DE. I'm in New Zealand and it seems the 2.0 Neo engine made it out here in a few auto R34's. The Neo is really quite different to the earlier version, with much lighter crank, rods and pistons. The pistons also run just one compression ring, so things look good for a high revving well ballanced engine once we are done. I am not sure on the factory specs of the motor because we are modifying everything to suit my R32 head, so stock measurements in this area are not critical. Similar to my previous engine the block will be decked and a little more taken off the head. Due to the way the valves sit in the cumbustion chamber hopes to get mega compression are out the window, but hopefully the torque I will miss out on can be made up with rev's -I like that kind of comprimise! Instead of trying to bash out some calc's on this, we decided to give the parts to the machine shop and get them to go as far as practable with what we have considering the car won't do high mileage. I'm picking the single compression ring will need to be replaced fairly regulary to keep it on song, but it's not a bad thing to get in there every now and then to check how it is all going. What are your plans for the Neo? Street car?

Do it for a point of difference on a roadcar yes, but don't expect any instant gains from it. The build aspect is fairly easy if you have access to a CNC machinist that can make the adapter plate and weld to what's left of your intake manifold. The secret here is what intake runner length you end up with as to how it perfoms and this varies on what other mods you have. I built my ITB engine for a specific class of rallying. I wanted to skid an R32 and have the reliability of an RB to run in a 1600 - 2000cc capacity class. (note a turbo would put a 1.8 multiplyer on my cc rating) It took a few years of tuning and tweaking, but four or five years on it is making easily over 100hp/litre, has great throttle response and is very competitive. I wouldn't be so keen to have my setup in a roadcar (especially a daily driver) as it just isn't that drivable in traffic. Most of that would be down to the cams I run and the fact it is tuned to function in the 5,000 - 9,000rpm region. 1,500 - 3,000rpm just isn't any fun surging along. If you outsource the work, yes it will cost you a bunch of cash. It will never make hp/litre like a Honda. It will sound cool. PM me if you are interested in details of the setup I run.

Geez, rip into the guys who want to build N/A engines... A 3.0ltr N/A twin cam will go hard if you can get enough compression in it. You just have to look how well the old L series engine goes in the light Z shell to know that. So I'm the guy from NZ who rally's the 2.0ltr N/A with ITB's. Quick note on what we did to get the compression up since hi-comp pistions for and RB20 are pretty much non existent. Like mentioned above, we machined the block to get the pistions proud when at TDC and also machined the raised edge off the outside of the pistions so they could come closer to the head. To test clearance we bolted the head on with no gaskest and turned the moter over. My cams have a lot of lift, so we were pretty keen to make sure the valves cleared also. This bumpped the compression nicely and mad the moter real responsive and lively. I rev it hard because it is only 2000cc, and I can't help myself! As you know the 3.0 will produce torque and you really should only need 7k. We are pulling it down at the moment because we think we can go a bit further with these mods.There does seem to be a bit of space in there. Will be doing the old fashioned pasterscene on the piston durring the dummy up to get a measurement of clearance this time. Good luck with the build, would love to buld one of these 30/25's with carbs!

Took about three years of tuning and racing before we got it really humming. Unlike more conventional RB setups (read turbo) there are no preset maps to start with for the ECU. Stpe one was to make it start, step two idle and so on... For the last five years I've been running this setup I have had the trumpets open with individual filter socks. A real pain having to clean them all the time because of the gravel dust, but clean filters makes a big difference to the power output. I am planning on getting an airbox built, but am too busy racing it to pull the intake off and make something up, plus it's going alright atm, so no point fixing it...

Been keeping an eye on your progress from here in NZ, the Silvia is looking good. Looks to be fairly torquey pulling from low down out of some of those turns. Quite a contrast to my revvy N/A that I have to keep strung out up on the cams, good fun though. First pic above. Is that brake smoke coming out of the front wheels? Must have been a pretty big stop coming in to there.

From in-car is sounds like the induction dissapears, but does make some good sound from the outside. Just off the 8,600rpm limiter coming up to the camera. ECU is a Link G4 and cams are a must IMO.

You're right, there is f all info out there on them. Didn't stop us from building a setup though. I've been running ITB's on my rallycar for a few years now and they work a treat. http://www.skylinesdownunder.com/forums/showthread.php?t=52581&page=14 Mine are 4AGE Toyota ones off a 20 Valve, mounted on an adaptor plate and the original intake runners. Cam, head, pistion work etc has leat to a fairly angry little N/A RB20DE. Has taken a few years of tuning and trying things as no one in NZ had done one like this, so it was a bit hit and miss originally. Mine runs open trumpets with individual filters, so all tuning is done from the TPS, which works fine now. As far as the brake booster goes I had the same issue with lack of vacuum, made worse by the cams I run. I run a Wilwood dual cylinder pedal box for brake bias, which also means I can run with no booster and it is a good leg work out. Good luck with the build, even if it does't go faster it will sound fantastic!

My ITB's wide open...

Now track widened another 54mm, fibreglass GTR front guards and 30mm fibreglass rears to capture the OZ Wheels.

^^^ Makes me wish my N/A ITB's weren't always covered in dust...

Shane from Tauranga. Race an r32 rallycar. 2ltr non turbo itb. Doing it sideways in the gravel every weekend!

R32 Skyline RB20DE 1998cc ITB's, ported head, custom cams, Link ECU etc Stock bottom end 131rwkw

Nice, a gravel rally thread on a Skyline website. I feel quite at home all of a sudden. Skyline's in bits at the mo doing a rebuild to see if we can find some power without cheating and putting on a hairdryer It's only been a month and these vid's are making me impatient. Might have to ship the Skyline over and come for a play some day! A couple of NZ video's for ya's.

Yep fully caged, just painted black and fitted tight to the pillars because I don't want to see it when driving. We found a heap of internal engine damage when we pulled it down, so much so would wouldn't expect it to start, let along run as good as it did in those videos. Had a slight fuel issue in a Targa where we couldn't get enough 10% ethanol fuel, causing some bad detonation. Then the car got stolen and thrashed cold a month ago, just to put the icing on the cake. So there better be a good performance jump once we are done...