rx-line

I've been using the search function a bit and the higher compression engines seem to be more common on the RB30 builds. Does anyone have dyno results for a RB26 in the 9.5:1 compression range or can point me in the right direction? 64-70mm turbo, ported head, cams would be helpful. Thanks,

What compression pistons?

Yeah, making more sense to pay for the rb25 box. Have killed 3 RB20 boxes so far. Running launch control,slicks, 6 paddle clutch and 1.5sec 60 foots royally dicks them. Usually Synchros wear off making the shift to second at full load near impossible, shift to third is none to great. I have broken shift forks as well. At the power I'm pushing in the 20 you'd be lucky to get weekend at the strip. Car weighs 2600 or so, ford 9" rear. I've gone so far as to do the 6-8 hour job of re-building one, didn't last a whole lot longer than other spares I had. I was going to continue with the 20 but the r25 tranny is a must and at that point it's too cheap not to get the engine. I like to idea of the using R34 ECU and wiring harness, hopefully they will send me a fuse box with the harness. Just trying to get into the 9's

Actually I was looking, the Stagea did not have TC correct? The one I am looking at does not have the large cylinder off of the throttle body. So that would make it a Stagea engine?

RB25DET NEO , AWD vs RWD trans Looking to swap my RB20det with an RB25det NEO and run the RB20 nistune wiring / ecu as it is in an rx7. Push to Pull Conversion, Intake manifold, shaft yoke etc. differences aside. However the dilemma arises when shopping the Canadian market for the engines. My biggest issue has always been the weak Rb20 gearboxes. Keep in mind I have the ability to modify the transmission & oil pan and that I will have to increase the driveshaft tunnel size anyway. All long blocks with trans, turbo, ecu etc. RB25det RWD S2 - $3200.00 (Don't really want anyway) RB25det RWD Neo - $2800.00 (Preference) RB25det AWD Neo - $2200.00 First question, do the AWD versions only come in Stageas? Or was there an R34 GTS-4? As it is advertised as coming from a skyline. Does the AWD version feature the same transmission from a R34 GTR? I.e same transfer case, gear set, 6 speed, etc. If so is it stronger than the RWD box? Lastly is there any mechanical / electrical differences from AWD / RWD besides oil sump? I heard something about Traction control on factory ecu being different, but likely won't effect me unless I maintain current harness for some reason.

Good point, progressive timing and rich fuel definitely helped my RB stay together for as long as it has. Heat is definitely the culprit in ring compression / failure, but the quickest way to heat is often cylinder pressure ( Boost, compression, nitrous, etc.) assuming everything else is fine? More Air = More Fuel = More Pressure = More Heat, I think i'd be right in saying that. 1.8bar would be relative to the amount of flow, what turbo are you running?

How tough are the automatics in these? Really don't hear much about them. Most basic autos with some miles don't seem to like a bunch of power added and start to slip. However a skyline auto is likely much tougher than the auto's I've had experience with.

I wouldn't be going past 25psi, typically stock rings are not meant for such high cylinder pressures. Especially in an engine known to have ring land issues In theory you would no want the rings to touch and compress on one another. I'd be looking at other items rather than boost pressure to hit 500hp. In my RB20 this year I did about 12 runs in a weekend at our local strip. I was upping boost constantly and ran a 10.67 twice with 25psi @ 131mph and 27psi @ 133mph (Different 60 foots). I then proceeded to run 29psi and 30psi. The engine still works "fine" and is fully standard stock internals, however it has a fair amount of blow by and I suspect piston failure due to cylinder pressures.

When my MAF was bad the car wouldn't rev past 3000rpm, it made my car run rich and when I changed the MAF it did not run right as the plugs were fouled. Thoguht I would share that. Pull the MAF sensor plug while the car is running, should make a difference on AFR's, idle speed etc.

From what we can tell the only thing changed was the filter, I would look at the Maf extensively to check for damage. My car would not start and sputtered going into boost when the plugs were fouled. Also check for ground wire to coil packs/ignitor.

Hahaha I guess this one takes the cake as there are no classes for RB20 powered cars.

Threads need to be lubbed in order to keep the steel alloy of the stud from galling the aluminum, this will give an accurate torque, rather than a false torque if galling has occurred. A false torque could cause a leak for sure. Also you might want to try torquing from the inside working your way from side to side to the outside of the head, we have had good luck with this. As for a reason things change a fair bit when you clamp a head to a block, it's surprising how things move. If the above fails I would look at the head and block to see how well they have been surfaced. Here's a thought as well, you might be experiencing above average crank case pressures due to you rings not being seated in with the new build. Make sure not to use synthetic oil when breaking it in, it delays the process by a lot. This may be exaggerating the leak. Hopefully this may help you.

Get a wideband, and a fuel pressure gauge, actually these should already be in your car. They help immensely when troubleshooting as you can drive down the road and help determine things like fuel filter, fuel pump, ignition issues etc. You can also see if your fuel pressure correlates with an issue in AFR, if they don't match than it could be an issue ECU/vaccum side. Rather than just opening the hood and looking for issue that can't be seen.

A strut/spring setup in the rear with quick/light compression and slow rebound will allow the car to squat and transfer more weight over the rear wheels. I woudl think the front would have a stiffer spring with high rebound in contract. This is what I can gather however. I can't tell if you have slicks or not but I went from 1.7's to 1.5's in just learning to use them properly (proper burnout heat). Also doing your burnouts in the water box will coat your wheel wells in water and when you get to the line and stage it drips down on the tires! This is bad. Also slipping the clutch off the line will cause you to get off the line super quick and without spinning tires if done right. Really a hard thing to master. Do you have launch control? what RPM are you leaving at? What tires are you running>?

I'll see if I can upload a video to youtube at some point. Here's some pictures for now. It was fairly close to lifting the front wheels in first and when hitting second as you can see in the photo. Higher launch control, a bit more power and some suspension tweeks might do it. The cars got some blow by issues now but still runs fine. I think I might make the jump to an RB25 neo as I need the bigger transmission anyway (been through 3 RB20det trans, typically synchros get chewed off within a weekend or you break shift forks).