StockyMcStock

my GT40 has the oil restrictor built into the cartridge, but it's plain bearing. have you guys heard of plain bearing GT's suffering the same fate you're talking about above? or is it just the ball bearing cores? also i'm using -6 braided speedflow lines, is there any way your lines can be too big? i'm worried that it will take a while for that volume of space to be filled with oil on start-up that's all. it's high mounted so the oil will probably drain back into the block when the car is turned off

i would imagine the springs for an R33 RB25 would be the same. if you want to get out of it cheaply, consider a set of 2nd hand GTR springs. i hear they are a direct replacement

i used the standard 25 head gasket from nissan and modified the front VCT/coolant gallery thingo so that it worked with the new block. time will tell as to how good it works.

always use a thermostat!

make sure the pins are correct and see how it goes. interesting about the series 1 coilpacks being a bit better, anyone else found this? NIB you mentioned using a GTR ignitor can help, is there much wiring and mucking around to do when installing one in place of the RB25 job?

before you do it all, wire ONE coil in and crank it, see if it sparks on that plug still. will save time re-wiring if it doesn't work.

platinum - i can see no major problems with getting the series 2 coil bracket and coils, skipping the ignitor and wiring them in directly. i beleive it will work just fine. if you can't get the bracket though, just remote-mount them with leads on the firewall.

not really. surely there'd be a few top-of-the-line bearings for the 26? you only need one company to make good ones and they're the ones you'd buy. for instance, i got genuine nissan mains for my RB30 but i almost went King bearings or Clevite. with the 26 you can choose genuine nissan first off again, as i would. but it may be a more common process than i think i guess, i just assumed all the drag RB26's used nismo or tomei (for example) bearings for the higher RPM experienced by the 26. very interesting subject though.

why would you use RB30 bearings in place of proper 26 shells? surely the cost difference couldn't be the reason due to the extra machining needed to make them fit?

the isky spring shop? haha sorry had to. just ask some engine parts suppliers, or a cam shop. i know tighe cams up here in QLD can get em if you're desperate.

yeah isky springs seem to be the go.

the yanks love em, and make lots of power with them. they are cheap because they use (from what others can figure out) machined-down T04 wheels through the whole range. that means each different size of wheel is not designed individually and optimised, so they're not quite as good as the new series of wheels. they do, however, work well and make lots of power.

that's insane, sounds like your tuner was taking his time then

6 hours! holy crap! 6 hours of tuning time is absolutely ridiculous, unless it were a race car. it should take 2-3 hours for a good tuner to get a 95% perfect tune going.

600cc injectors should get there - but i'd go 740 nismo items to give you a bit of leeway. the oil cooler will be fine, just because the engine is making more power than standard doesn't mean the oil gets significantly hotter.

are you rebuilding the engine FULLY each time the bearing gets spun? try blowing compressed air through the bearing supply gallery, it may be blocked with gunk. other than that, i'd suggest a supply/pressure problem, possibly because of the sump baffling issue above.

on a side note, i find it hilarious that a piston can be "rated" at 10psi. does that mean the piston will be okay on a motor with 10psi, huge back pressure, poor camshaft design and 14:1 compression? or does that mean that the piston will be okay on a motor with 10psi from a blower, with no back pressure, a perfectly selected camshaft and 7:1 compression?

hmmm..... so you can do plenums with the AAC valve on the rear eh? i might be interested in one of those.......

all good reading and a cracker of a thread guys! i'm not too worried about improving my power output, or my throttle response with a plenum change. i just need a front-facing plenum because of space restrictions. modding the standard one and keeping the AAC stuff at the rear is the best option i can see, as i will be running a powerFC which uses this stuff for cold starts etc. if i could get a custom plenum that incorporated all the AAC gear, then i might consider it. but modding the standard one just appears to be the best way about it at this point in time.

see now that is a good looking job there - pity you're in perth i could have used your fabricator to do another one. how much did it cost to get done?

no, it would create a horrible obstruction to flow. air conditioning textbooks are very interesting reading. IIRC one 90 degree bend with radius equal to diameter of the pipe is the same as three metres of straight pipe.

sorry i was referring to porting the inlet runners there, which is what most people do with a custom plenum anyway. how'd you set up the thermometer ISL33P? i'd be interested in doing this myself but you'd need six of the buggers, making it possibly very costly? 33SOM: i'm using a powerFC too, which is another reason i don't want to ditch the factory plenum with the AAC valve. cold starts etc are very useful things to have working well i have found.

the only real way to tell if it's leaning out a cylinder or two is to take EGT measurements off each cylinder. simply making more power is not what you're looking for. you want a plenum that will distribute evenly, not just flow more air, which is why i said flow testing is largely useless. all it really shows is that a runner has a larger diameter than another and will allow more air through at a given pressure. just getting more power out of it is not such a useful indication that you have a better plenum, for instance it may simply be making more power because three of the cylinders are running white hot exhaust runners because of the mixture leanness there. if i could afford a decent jap-brand plenum i would get it, but cutting up and modding the standard one would be a lot cheaper.

i don't believe there is any significant engineering behind ANY of them, that's the problem if i really wanted to i would make one myself but it will give similar results to the standard modified one i believe, just cost me a lot more.

i don't expect it to improve power at all, i just have to have a front-inlet plenum because there's a supercharger and a GT40 on the other side of the engine. there is no possibility of retaining the standard inlet design at all. instead of buying a custom unit i would prefer to just mod the standard one cleanly, but whether or not the charge distribution would be good at all is anyone's guess. having said that, i have no more faith in a brand name plenum than a modified standard one, doing flow simulations on similar systems in solidworks has led me to the conclusion that it's basically all guess-and-check until the engine doesn't blow up. flow testing is largely useless for a complete system of inlet pipe-plenum chamber-runners as it doesn't simulate what's actually happening when the engine is on full song. pressurised air in a system feeding six runners out of a box is a LOT different to just pulling vacuum through the pipes individually and measuring how much comes out. anyway enough ranting - how much did it cost you Booky?