mtnickel

Might not even idle fast enough when cold...unless you have some way to manually open it. I forget which is which, but there is a valve just for the A/C, and one just for the idle. The A/C one you can probably do without (obviously if you don't have A/C). Are you using a stock ECU? Other solution is to use one of the coil type Auxilary valves for warmup. It just lets more air in for a while till the coil heats up and shuts it (apply 12v at startup). That's a common solution for cold starts on megasquirt cars that don't want to deal with an idle valve. (like any of these: http://www.carpartswholesale.com/parts/nissan/nx/auxiliary_air_valve.html ) Mark

As stated... IMO, you're asking for trouble wanting 400whp on the rb20det without cracking the bottom end. But if you plan to build it a little, you'll need....pistons,rods,bearings,oil pump, arp rod/head/main bolts, and a bunch of seals. That's just on the inside...then as was previously stated.. "every one of these swaps will require custom exhaust, engine management, custom intercooler ect ect non of which is cheap" not to mention a BIG turbo. For the cost of building an rb20, you're probably 'better off with the Rb26. It'll handle 400whp reliably without touching the bottom and, and can get you pretty close to that HP on stock turbo's and injectors to boot! It's economically the best bet. Injectors and turbo for RB25 to get you to that HP level will be about 1200, or $600 if you can handle some fabrication and ingenuity (I'm using holset turbo and STI side-feed injectors on my rb25, $350 and $180 respectively).

Google is your friend here... http://www.skylinesaustralia.com/forums/Rb20-Limits-t238632.html The general consensus that i've seen is about 350whp for the RB20det. But a big question here is what is deemed "reliable". I asked myself the same question when deciding what HP to shoot for on my RB25. sure i've seen plenty dyno's with the engine making 400-460whp, but how long will they last. Daily driven, probably a long time if properly tuned and maintained. But with auto-x or lots of 1/4 mile runs, or any trackd days, the life could severely be compromised. I've settled on about 350whp for my comfortable goals on the rb25det. That's 65% more power than stock and over 410 crank HP. By comparison, a stock LS2 6.0L corvette engine makes 400hp. Perhaps i'm a pesimist, but from all my reading, i'd keep goals to 330whp Rb20, 375whp RB25, and 425 whp rb26 when not touching the bottom end. If you need more than 425 whp in a Z you should probably be building it up with the bare minimum of head studs, metal head gasket, better oil pump, and likely pistons/rods. Mark

I'd say stock type Nissan gauges aren't very accurate. Plus the metric Bar readings are less desirable for me anyways. I like where this thread is headed though and can feel a sticky coming. Also loved the idea to use 2 Water temp gauges for oil and water. I too am one in favor of keeping all stock gauges. That AutoGage looks great and very stock like (saw from your website). I'll probably use the same one. I haven't found much info on the tachs though. It'd also be nice to konw the difference between the 3-wire, 4-wire tachs, and which ones use magnetic pickup or the coil signal (I hear 4-wire = inductive pickup, 3-wire = current version (pre-74). Anyways, i'm ranting...but appreciate the input and effort here. Mark (260z - rb25det in the works)

almost forgot... http://www.nismoparts.com/catalog/?section=934 link

Nismoparts.com 161, and 28 for the pan and pickup Respectively. I think i'm going to have a go at just cutting the entire bottom off (1" from flange) and welding it back up...converting front to rear also will wing the pan, put in a windage tray, and confirm the baffling is still decent. The winging will help anyways. Mark

GREAT SUCCESS. I was worried about getting the speedo hooked up with my swap...can put my worries to rest. Just gotta figure out what gear i need. Mark

For what it's worth, from my clutch research, the clutchmasters are looking good. Aparantly in a direct test on a Ford Probe DXD (south bend) vs Clutchmasters PP, the Probe one was near stock levels, where the Clutchmasters had significantly more. Additionally, they use geometry to maintain a stock pedal feel (think leverage). http://www.rr-racing.com/SB.htm comparison. Specifically i'm looking at the segmented kevlar fx300 rated at 110% over stock load. Upon emailing them, they stated about 425lb ft of torque. That's not quite 110% of the stock 220 ft lbs, but still pretty good for my goals (350whp RB25). They are retail @ $500, but i swear i saw them on ebay a while back for only $300. Now all i can find is $405 ish. I might call them directly and see what sorta deal i can get. What clutch did you end up choosing? EDIT: Upon further investigation, i found that the PP tests might be biased. Another showed the DXD plate doing aprox 28% increase over stock which is close to their 30% claim.

here's what i'm talking about for completeness...

I think i'm gonna go for the more widely available z32 NA trans even though shift position is weird. I posted a link in the RB forum about how i might have mine. Instead of using that linkage bar at all, you bolt the shifter right to the output rod...then you need to make a pivot somewhere. Should move the shifter position a good 4" or more forward. Mark

I actually just found a good source today. Used to be nagasaki jdm motors, they went bankrupt and OSAKA japanese bought them out. http://www.osakajdmmotors.com/ Prices look pretty good. Now i can get a low miled 300zx NA trans for $250...that seems good. Funny that the turbo's were $450 for just a different bell housing. Decent price @ $2k for RB25 engine and trans...but probably RB20 trans. Otherwise JK japanese has a good selection although a bit more money. As for parts...right now i think I'm OK...just need to get the transmission thing sorted out. Need those lower tranny brackets and dust cover but the engine place might have those. I'm a little TO'd that when i bought the project car, the engine with it (rb25) was all half taken apart...just hoses, brackets, intake, things like that.

Hi guys. I'm debating which transmission to put in my 260z with rb25det. It will definately be an FS5R30A (z32, z31T) Transmission...but my question is based on the reliability of these units. I have access to 88 300zxt 30a transmissions from wrecked cars. Quality is not guaranteed and these trans are now 20 years old. The benefit of these z31's are the better shifter placement. Price is $400 Alternatively, i live on the west coast (vancouver) and have access to LOW miled JDM 300zx Z32 NA or Turbo transmissions. So potentially could get a good condition one. Pricing is $500. So, what is the reliability of these transmissions? Are they known to have grinds? Gear lockups? Would it be better to suffer the modification for the z32 transmission for benefit of low miles, or just go with the older one. Mark

The thing is, cost is not close. I can get an Rb25/rb26 bell housing for about $100 Z32 trans = about $400 for low miles and NA (not beat on). Comparatively, Rb25s are very hard to come by and pricing is usually 800-1000 here. Also, swapping in another z32 trans if need be (heaven forbid) would be pretty easy too. I like fabricating stuff, so i think it'll be fine. Just gotta find those eyelet end things. Mark

I've found Bell housings for as cheap as about $100 shipped. But more typically $130-150 will get the job done. Then a newish JDM z32 trans is the best bet in my opinion. If you want to know where to get a bell housing...let me know, i can connect you with people...these specifically are in canada, but i'm sure they will ship to US.

The more i think about it, the more i want to do it this way. The hardest part will be finding good bushings that support the shift stick (like the one shown above). My pivot rod will be considerably shorter (6" or so) and such the bushing/eyelet will need to have decent lateral flexibility...it certainly can't be solid mounted. My only other option was to try and track down a z31t trans or a 3.0l V6 hardbody 2wd, or 2wd pathfinder trans. These are very close in size to the rb25 trans (and shifter location). The hard part is finding a good condition low miled one. Good condition z32 trans are easy to come by since many JDM importers bring them in...2wd/hardbody pathfinders, not so much.

Hi guys. Just wanted some input on the shifter linkage of the z32 trans in the s30. I know some of you are cutting the linkage, but to me this seems like it's putting the geometry out of whack. I take it the shifter works by a) twisting the rod, and pushing or pulling it. With the factory length rod, the twisting at the end of the long rod doesn't move the angles out that much, but with a short rod it surely does (since the bottom of the shift stick move laterally a decent bit. Perhaps it's a non-issue, i don't know. How do you guys like your shifter action (for those that have modified yours)? I am thinking about doing something like this... That rod you see going back is just a pivot point...no idea why he made it so long. I was going to do something similar but pivoted off the top of the trans somewhere.

Will be interesting to see the results here. On a side note...for those who have put the z32 trans in the s30 chassis...would you recommend it? OR should i go through the hastle of finding a 2wd pathfinder / 3.0L 2wd Hardbody or /z31 turbo 87+ trans. These are all basically the same as the rb25 trans, but more difficult to find. I can get the pathfinder one on ebay for about $600 shipped...but mileage and condition won't be fully known...OR i can get a basically newish z32 NA JDM trans that will surely have tones of life. Can i get the shifter far enough forward by cutting the linkage? That shifter linkage really baffles me in how it works (regarding the shaft and the geometry of it...guess i'd have to see it in action to understand). Just thinking out loud...but right now i'm leaning to the z32 trans for availability reasons (plus it's cool to say in the end that you have a z twin turbo trans).

You still have to swap bell housings though, right? Also, anyone have any idea how much power the rb20det trans can take? (same as a KA, or SR). I'm only going for around 300-350whp on my rb25 and currently have an Rb20 trans....just wondering if i just just use that (saves me tracking down an RB25/26 bell housing and dealing with headache of z32 length). Mark

Where did you get this Throttle cable...with the new ball and all. what length? Thanks Mark