rockabilly

i run a std head and valves, ported and polished by me, spool rods, cp pistons, tomei oil pump. 800bhp and 660 lbs of torque @ 1.5 bar boost, why waste so much money on parts not needed. i would spend the money on a gearbox and clutch, christ you will need one, a very good one..bernie

Just got round to uploading these from last year, so I thought I would post them. Also here is the famous 360 spin at spa with me driving and nick as passenger.

so fair points. i had a etm manifold and a gt35r fitted before with a 1.06 rear. but the motor was just to much for it,. we ran it at 2.2 bar but it could not produce enough air. the engine is designed to be as responsive as possible but have 800bhp @ the fly.. the car is awesome to drive and the turbo sounds superb. it just needed about 500-800rpm quicker spool. if you use the gt35r at 2.2 bar then when you get to 7300rpm its out of puff and dies. the dyno showed this. yes its an awesome turbo but imho too small for me.we do quite often get the chance to stretch the cars motor upto 8000rpm in 5th..lol p.s some say why rev to 7300 when the power will be there in the next gear. until you have driven a responsive 30 with a gt40 (gt4088r,gt4094r,gt4202r)based roller bearing turbo at 1.8 bar boost and 8000rpm, you have never lived...lol

update guys, housing been sorted, just waiting for it coming home..

take the car to a garage, get the exhaust probe that normally goes in the tailpipe, but put it in the expansion tank for the radiator, dont let it touch the water ,,just let it sniff, any hydrocarbone reading will show hg failure.. easiest and cheapest way to check.when combustion pressure on a failed hg is the fault and pressure is getting in the water system then also cylinder fumes are in there too, the probe will pick these up..

any news?.

i have arp studs in my awd rb26/30 gtr, you have to trim one down to get the sump on, no issue though..

rb25 sump bolt straight on no adapter bonnet issues yes in a 32 not a 33/34

i suspect the issue is related as with all these large power build to the fact that 400kw,s is almost double the std output. yes nissan recommended 7.5/30 for a 250bhp rb25det. once you stick some forged pistons in there with twice the piston to bore clearnance than std, an oil pump that flows almost 1.7 times more than stock and alot larger amount of air pressure from a bigger turbo the factory specs go out of the window. i should have wrote 15/50w which is what alot of the big power cars tend to use. .yes you can fit oil rstrictors and oil drain all will help. in my eyes thinner oil in a big power car always seem to be an issue, seen it many times before, if is not leaking everywhere its blowing out everywhere. i just think its no suitable..my own views. as for 20/50w,this block was used along time before nissan ever put a twin cam head on it.the oil grade change had to be as you cannot run a turbo car on a multigrade oil, it burns it. so we have a 40 year old crank designed for 20/50w, running a turbo or two. maybe in oz people use a 0-30w oil, but i have never seen a car run it here in the uk, especially a big power car, which for an rb25det this is..

0-40w wont be helping you..too thin.. this is a 40year old engine design, it was made to run on 20/50w when new. least i would use is 10/40,, just my view..

i had a t3 gt35r with a 1.06 rear on a etm manifold, made 670bhp @ the fly @2 bar boost. thats on a rb26/30 big cams and 8000rpm. that was its lot, we tuned boost up but no more power just heat..

hi guys, thanks for the interest in this thread, good reading. i have sent my .96 t4 twin scroll rear housing to the states now for this mod to be done, mine wont be on the road till mid april for testing as i have a couple of jobs i am doing right now on the car. another reason i chose this one over the sp one is there is no spindle in the exhaust flow path, when the gate is in the centre postion the turbo will be as before, its only when the gate is swung over the flow is forced onto one scroll, the guy modding the housings has done back pressure testing with good results, you can decide at what boost pressure you want the gate to swing too.also if it does not work i only have to buy a rear housing, save me cutting a 6boost manifold to bits which i would need to do with the sp one..bernie uk price wise. it cost about 630 us dollars plus postage. iknow its not cheap but may save me time in going twins..lol imagine having 800bhp and boost from 3000,full boost buy 4000rpm.lol if he can get a gt4202 to spool to 1.6 bat by 4700 on a mitsi 3000gto then i am impressed.

thats what i saw when i looked at it BoostdR.. i can see any great hotspots on this set up, he says when idling the gate is in the closed position until positive pressure is reached to the level of the spring you choose, also on gear changes as boost drops the same again, it closes and you have major instant responce. i will try it out and see how it goes. the guy works for a living and this has been a 6 year project for him, he could not find suitable people to make the valve cheap enough so he bought his own cnc milling machine and made it himself..

well....i am at the moment removing my rear housing from my gt4094r and sending it to the states to have a different type of quick spool valve machined into it. check the quick spool valve thread on here for pics..ifi dont like that then will sell and deffo fit twin 2860,s ....

just waiting for prices mate. will post up the two prices when i get them.. think its similar to the sp one by the time you have posted your housing there,its been modded and posted back. will update when i hear more.. i do know though that on a 3000gto with a gt42 turbo. 20psi was acheived by 4300rpm with the valve and its been on the car now 5 years no issues..

i thought this but you can have it in stainless or inconel.... this is an email clip from him to me. We have two models. The standard model comes with stainless steel 304L internals, and the pro version comes with nickel 600 (Inconel) internals. The pro version provides peace of mind for those who think they will be running in very high horsepower and temperature environments. Both models come with all required bracketry and the actuator so the unit is a complete bolt-on kit.

here are the only pics i have of his device.

hi guys, resurecting an oldish thread. i like the idea and did some research. i have found a guy in the usa who modifies yours existing t4 twin scroll exhaust housing. so basically he cuts out the divider and fit a pivoted flap in there, similar to the spool valve. differences here are. the valve is in the exhaust housing so you still keep the twin scroll manifold and no sandwich plate to fit, so dump pipe still fits also the flap is at 45 degrees when closed so make a nice transcient flow of exhaust gas and creates no blockage or hotspots. i am going to be sending my rear housing to him for mods so will try to update on the results. i like th spool valve idea but not there design, i would imagine massive heat build up behind the closed flap where this idea eliminates this. any thoughts on this type of design guys??. bernie

waxracing, tell me you are going to put another tensioner/idler on that cambelt before you install it.. that will be fun in a rear wheel drive car.lol

i just got a std rb26 one and extended it..simples

i have to agree, having driven it in my 33gtr last year nothing can compare, forget playstation,the track is nothing like the playstaion in real life,yes the layout is but the gradients dont come through on the playstion, dropping into the corner they call the crowd pleaser at 100mph on a tight 90deg bend going into a 1 in 3 descent cant be replicated..

could anyone overlay my graph onto avs please. just for comparisons..thanks

so the graph only goes to 6500 rpm?.

so 87 is 87 divided by 28 times 1000 correct?. 87/28 3.107 x 1000 = 3107rpm

hyped6, i would be checking you have not got a collapsed silencer. we have a 33gtr here making 500bhp @ the hubs on std manifolds. its not the manifolds thats the problem. do you still have a cat fitted. if yes check its not collapsed.