Chris Wilson

RB26 engine, Tomei oil pump, standard out of the box pressure relief valve shims, and two new Garrett GT2860-10 turbos. Stock oil feed lines to the turbos. Do they need any additional restriction? Here in the UK I have asked 5 people, all well versed in either Skylines or Garrett agents, and have had 5 different answers... I am told by 2 of them that the ball bearing turbos have restrictors inside them, after the oil feed female port, and invisible externally. Others say the Tomei pump delivers so much pressure a restrictor in each Banjo bolt on turbo female fittings of 1mm is vital. Others say no restriction is needed. Another says 1.5mm.... Real world experiences please

Is there a preference as to which type of stock coil to use on a modded RB26 engine? I have early RB25 coils with internal amplifiers, are they just as "powerful" as the coils with the separate amplifier? Thanks.

Having built a virtually brand new RB26 engine to replace the RB25 in my R33 GTS-t car I have come to the stage of weighing up the PAS pump mounting. The RB26 crank damper has the PAS belt pulley out further away from the front end of the engine. I see that it lso ha an extra belt rib, 4 rib belt on the RB25 damper, 5 rib on the RB26. If I change the pulley on my RB25 pump, and fit the RB26 cast PAS pump mounting and the dedicated tensioner bracket, is that going to sort it? Or do I find a good RB26 PAS pump and mounting complete? Any clear photos of the RB26 pump, I need to see if the hydraulic pipework fittings are the same? Thanks.

Here in the UK the dump pipes are commonly called the turbo elbows, and it's those to which I was referring. I believe the HKS ones have provision for the stock braces, which I really would like to continue to use, I don't suppose anyone has any decent photos of an HKS "dump" do they? Thanks for the reply.

Hard to tell from photos, but to me those valves look very pocketed, and that would explain the rather poor low lift flow figures.

Th cartridge is just a dummy the turbo people sent to make the manifold from. The runners sze and length were based on RPM expected, as well as getting the runners within 10 m of equal length. Availability of Inconel at a sensible price had some influence, too. Kept the ID fairly small to keep gas speed up.

Having all been so helpful I thought you guys might like to see where I am now with this. Inconel manifold, supported turbo, split gate dump, and silencer now dry built, awaiting final detailing before ceramic coating, along with turbo turbine housing: Thumbnails at http://www.gatesgarth.com/4age/primary/primary.html

Looking at on line photos of HKS and Tomei turbo elbows there does not appear to be any boss to bolt the stock pressed steel braces to them, which go down to the engine block, to help unload the manifolds. Do their makers not allow for these braces to be used then? Thanks.

I want to ditch the stock CAS and run separate crank and cam position sensors to feed my Motec M800. I would welcome a look see at any other peoples set ups. I'd prefer to keep the stock crank damper. Thanks.

Asked this question on a couple of other forums, too. The vast majority of people who replied suggested a GT3071R with a .64 A/R, and Turbo Dynamics and Owen Developments concurred, so I have ordered one of these to do initial trials with. the T28 footprint helps a lot, as the installation is very tight (see IrfanView HTML-Thumbnails if interested). I took the car down to Thame this morning and Primary Designs are making and fitting an Inconel manifold, support bracketry for the turbo, and a silenced exhaust system, all thermally coated in Zircotec. I have used primary designs for an F3 system, and for some prototype work before, and can't speak highly enough of this company. They now take on some general motorsport fabrication work, too, so there's less toing a froing than there used to be, as they can fabricate ancillary stuff in house. I justify their high prices by telling myself 60% of the F1 grid can't be wrong in using them They were making a new Arrows BMW Megatron turbo manifold, and it was truly a work of art, more deserving of the Tate Modern than any exhibit I have yet seen there They should have a gallery on their web site, some of things they make are very deserving of photographic record. http://www.primarydesigns.co.uk is their place. Thanks for all the fast advice, committed to this turbo now, so we'll see how it goes. I have decided to struggle and remake the rear bodywork to accomodate and air to air I/C. I may well run some cams with less duration when I have the engine out for the low compression pistons and refresh. Thanks again

I have photos of a Gt 30 / 40 mocked up on one of these manifolds on my RB25 engine. Compressor housing fouled the engine mount rubber isolator slightly, a bit of judicious cutting solved it, or a different mount would.

I would quite like the simplicity of a NONE water cooled housing, but I am also keen to have a Ni-Resist turbine housing, having seen how a standard cast iron turbine housing on an IHI RX-6 (Apexi) turbo warped on my Skyline engine. I know. I ask too much....

Just to clarify I am looking for 380 BHP at the engine flywheel. Fuel would ideally be UK Super Unleaded (98 RON) but I would stretch to a 50 / 50 Super Unleaded / 118 octane leaded race fuel mix. Management is going to be Motec M800, engine will be on dual twin choke 48 mm throttle bodies. Pics of the thing as is, awaiting me taking it for its manifold build are here: http://www.gatesgarth.com/4age/4age.html Thanks for the replies, keep the ideas flowing please

I know there are few really clued up folk on turbo sizing here. looking for suggestions for the following race engine spec: Toyota 4-AGE 1.6 litre Formula Atlantic spec engine, currently an N/A producing about 208 BHP. Will keep the 304 degree duration cams currently in it, bit compression will be dropped from 13.5 to 1 to 8.75 to 1 with new pistons. Revs safely to 10,000 RPM. looking to achieve about 380 BHP in a 580 kilo Sports GT chassis for track only usage. Transmission is six speed sequential Hewland FTR. Exhaust manifold will be custom made (in fact the car is in at Primary Designs on Wednesday this week, so I need to decide on a turbo by then). Can be divided or none divided turbine housing, externally or internally gated, and I have a spare new Tial 44 mm external gate to use if required. Intercooling will be by air to water and should be pretty efficient. Looking for some reasonable power starting about 5000 RPM 'ish. Turbo Dynamics suggested a TO4R with divided turbine housing, what do you guys think? Thanks.

Motec now have a forum monitored by Motec Australia staff, no doubt someone there can answer your question: http://www.motec.com.au/forum/ Please post up any info here, this interests me as well. Thanks and good luck.

Looking for a company to ship an R33 GTS-t Pfitzner straight cut, dog box gear kit to the UK, with billet forks. Who might do a good deal over there? Thanks.

Sure looks like an RB25 block to me, no provision for rear turbo drain, different head gasket pattern. Not familiar enough with an RB30 to say if the block could be that. At .50 mm oversize and with rusty bores you should still be able to rebore it and be safe. The block needs a deck skim, too, to clean the head face surface up.

Any decent photos of where people have plumbed a rear head oil drain into an RB26 cast sump please? Thanks.

I see some RB26 engines with welded on pipe adaptors in the top water rail (above the intake manifold). These, often 3 of them) feed into a water swirl / bleed pot at a higher level. Presumably the idea is to remove any steam pockets. My set up is in bits, bead blasted. I am wondering if it's worth modding the rail for this? Car is for track usage, all steel RB26 on twin 2860-10 and Tomei 280 degree 10.8 mm lift cams, on Motec M800. Is it overkill, bull or a worthwhile mod? Thanks.

Single Apexi RX-6 turbo on mildly tuned RB25. Tomei rod bolts, 7750 RPM limit. Admitedly engine had done a LOT of track days, but never over revved. looks like bolt failure, but the engine I am building to replace it will have either RB26 rods or Carillo / Tomei in it. Full pics at http://www.gatesgarth.com/bang/bang.html Expensive...

Got a Trust sump extension with the extended oil pick up strainer pipe on my in build RB26 engine. According to FAST parts CD the RB26 pick up uses a gasket between the pick up and the block. The Trust type pick up has a groove as provision for an O ring. It seems the RB25DET pick up uses an O ring, should I use one of those? Anyone come across this before? Don't want any air suction leaks!! Thanks.

Must put my glasses on before posting (smacks forehead, seems obvious now, sorry... ) Thanks!

As this engine is mainly new bits I have no witness marks to help me. Which way around does the crankshaft toothed sprocket for the cam belt go, it has a ridge at one end. The factory manual shows it has a right and a wrong way around, and shows an arrow, but the description of the arrows meaning is in Japanese.... Thanks.

I am thinking of removing the oil to water heat exchanger stuff on my new RB26 N1 block. I would make an 18 mm to 3/4 UNF male to male adaptor for the block and bolt on a thermostatically valved oil cooler sandwich plate direct to the block where the heat exchanger elbow normally sits. The oil filter would then screw straight on the adaptor. What I would lose are the bypass spring loaded ball valves that allow oil to bypass the filter if it gets blocked , or can't take full flow cold oil, (which are in the stock elbow). I am running a Tomei oil pump, will this be an issue? has anyone done this to tidy up the block and unload the water coolant system from dealing with engine oil temperature reduction? Engine is track use only, and will be properly warmed up, with regular oil changes. Thanks

If you don't tell the engine it'll never know your dark secret. So long as they are the right diameter, fit the cams, and have the right number of teeth at the right pitch they'll both work fine. So yes, they'll mix and match perfectly. Just Loctite up the adjuster screws once the timing is set, for added insurance.