EFR 6255 Discontinued.. 6258 Here I Come!

I was initially at a dilemma on whether to go for the smaller snail in the BorgWarner EFR (Engineered For Racing) range or to settle for something slightly larger such as 6258 since Stage 2 of my engine mods entails significant cylinder head and camshaft profile mods. You know me la... Being an NA Bagus kaki since I started modding cars I like my forced induction engine to behave like a large capacity NA engine without having to rev to kingdom come for some decent power. To illustrate my dilemma the specs of the 6255 and 6258 (single scroll T25 flanged version. The twin scroll version uses a T4 inlet flange with a larger 0.92 A/R) is as follows:

• 6255 and 6258 A/R: 0.64
• 6255 and 6258 Compressor Wheel Exducer Diameter: 61.47mm
• 6255 and 6258 Compressor Wheel Inducer Diameter: 49.6mm
• 6255 Turbine Exducer Diameter: 55mm
• 6258 Turbine Exducer Diameter: 58mm

(Dunno what I'm talking about? Read more about turbo terminology and details in Garrett's excellent faq)

The only difference is a 3mm larger diameter exducer for the 6258's turbine. More details can be found in BorgWarner's turbo website TurboDriven.com. The website includes an excellent match bot program that will assist in turbo matching. The decision by BorgWarner to discontinue the 6255 once current stocks run out has really made the decision for me. Apparently the decision to discontinue was because in many customer cars the 6258 has proven to spool as early and as well as the 6255 yet has more top end! The 6258 is rated from 225 to 400hp while the 6255 is rated from 200 to 350hp.

 To summarize on why EFR:

• Gamma-Ti turbine wheel that has about half the mass of an inconel version found in majority turbos
• Dual Ceramic Ball Bearing Assembly with Metal Cage.
• Forged Milled Extended Tip Compressor Wheel ala Garrett GTX
• Stainless Steel Turbine Housing. Bye bye rust!
• Water Cooled Bearing Housing. Bye bye ricer spec turbo timers!
• Large Internal Wastegate. The EFR can be configured for external wastegate operation if you so wish.
• Compressor Recirculation Valve aka BOV. No need to purchase a separate BOV.
• Boost Controller Solenoid Valve allowing ECUs to control your boost strategy if your ECU has this feature.

Graphical view of the EFR's features

More details can also be found in my earlier post. Picture of the 6258 provided by BorgWarner

6258's Compressor Map

Technical Drawings provided by Borg Warner



 The order is now out and hopefully the snail will arrive by end January. Patience is virtue.

Happy New Year 2011 Everyone!!!

Tomei Type S Fuel Pressure Regulator

A Bro once told me "If horse no eat grass how can horse run?". This is extremely true for engines as before you can increase the power you will first need to ensure the engine's fueling demands are met for the power you want it to produce. The fuel to the engine is the grass to the horse. Please forgive me for being phylosophical but I find it ridiculous whenever someone says that with component or upgrade X you can have a major increase in power while saving fuel. Stay far far away from such claims or snake oil.

The three major fuel supply mechanical components for the Slowtra's engine are the fuel injectors, the fuel pump and the fuel pressure regulator. The fuel pressure regulator or FPR's job is to maintain the fuel pressure in the engine's fuel rail. The fuel pressure regulator "regulates" the fuel pressure in the fuel rail  by returning excess fuel back to the fuel tank. Some of the newer engines such as the Honda K20 run a returnless fuel system which dispenses with the need of having a fuel pressure regulator. The ECU takes over the role of the fuel pressure regulator by altering the injector pulse width to give a precise fuel delivery.

Picture below of the stock fuel pressure regulator

Once the engine's fueling demand is significantly increased the stock FPR becomes a redundant paperweight as it is unable to cope with the increased fuel pressure from higher flow fuel pumps and larger capacity injectors. The stock FPR is also not adjustable hence one cannot adjust it to increase or decrease the fuel pressure. The fuel pressure at idling for all QG engines as stated in the service manual are as follows:

Vacuum Hose Connected

Approximately 235 kPa / 2.35 bar / 2.4kg/cm2 / 34psi

Vacuum Hose Disconnected

Approximately 294 kPa /2.94 bar/ 3.0kg/cm2 / 43psi

This is where the installation of an aftermarket FPR becomes critical as the fuel pressure can be adjusted  to suit the engine's fuelling modifications. I was initially going for the Sard FPR but decided on the Tomei instead as the Sard is becoming too common. Having a Bro using the same FPR help convince me too! You know who you are :) Also while the Sard is initially cheaper than the Tomei it only comes with one type of end fittings (the push fit type) and one will need to purchase AN fittings separately if one decides to go the AN route or purchase the SARD FPR which comes with AN fittings standard at additional cost. Pictures below of the Tomei's Type S FPR's box

The contents of the box sans manual. Lovely looking decal. Wonder where I should stick it? :)

The excellent manual is in both Japanese and English.

Details of the Tomei Type S FPR can be found here. Type S probably means "Small" as Tomei has a physically larger FPR it calls the Type L which is recommended for high flow, big power and high boost engines. Tomei may call it small but I can tell you compared to the stock FPR the Type S is Gojira! The part number for Type S is 185001 while Type L is 185002. Closeup of the Tomei Type S

The mounting bracket. Tomei separately sells nicely customized fuel rail adapters for specific performance engines. Obviously QG engines are not in the list but I'm not planning to use the stock fuel rail anyway so not a problem here. If you're looking to purchase the Tomei Type S or L please ensure you are getting from reliable sources as there are already fakes around. Details of the fake Tomei FPR can be found here. The problem is even more prevalent with the Sard. The first guiding principle when dealing with such problem is please don't be a cheapskate. If you're being offered a Tomei or Sard FPR at prices to good to be true then it probably is a fake. The regular Sard FPR with push fit end fittings retails in Bolehland for RM3XX while the Tomei is slightly more.

More details to follow post installation. Please be patient as this may take a while :) Next will be my upgraded injectors and fuel pump. Stay tuned.

5Zigen Honda Civic Type R FD2 Currently the Fastest FF Racecar in Japan

The 5Zigen Honda Civic Type R has broken the Tsukuba record for front wheel drive and front engine cars with a scorching 58.222 seconds during the RevSpeed Time Attack event on December 10th. To give you a comparison of how fast that is, a stock Nissan R35 GTR in the hands of a top driver will do around 1 minute 2 seconds. The CTR is an all out race car though. Details and pictures of the car can be found at the following:

• Speedhunters
• The Octane Report

Unfortunately for Honda NA Bagus fans the car is turbocharged! Laughing gas is also a feature to extract more power and to minimize turbo lag. Never underestimate your everyday front engine and front wheel drive sedan grocery getter.

Engine Spec

This is an early draft of what I expect the Slowtra's engine to be. This is Stage 1 btw.

Engine Assembly
Pistons: Ross custom forged.
Cylinder Head: Stock
Head Studs/Bolts: ARP
Conrods: Custom, steel forged. Supplier TBD
Crankshaft: Stock
Crankshaft Big End Bearings: TBD
Headgasket: Stock is MLS steel but not good enough for the boost & power level I'm aspiring so it'll be either the Fel-Pro Permatorque MLS or Ajusa 3 layer MLS. Might get both for R&D since these don't cost that much
Cylinder Head: Stock
Cams: Stock
Valves, Springs & Retainers: Stock

Turbocharger Assembly
Escargot: Borg Warner EFR 6255/6258 i.e. equivalent spec to Garrett GT2860/2871R/GT28RS except tricker and faster spooling. Details in upcoming post
Turbo Manifold, Downpipe and Exhaust: Tonnka
Turbo oil and water plumbing : AN fittings with braided hose
Wastegate: Check EFR Internal
BOV: Check EFR CRV (Compressor Recriculation Valve). No ricer spec sounding BOV please.
Boost Control: TBD

Cooling System
Oil cooler, sandwich adapter plate & fittings/plumbing: TBD
Intercooler: Garrett
Intercooler piping: Tonnka
Intercooler connection: Possibly Adel Wiggins if budget suffices else constant tension hose clamps
Water Injection System: AEM or Cooling Mist
Radiator: Koyo or Mishimoto Automotive
Thermostat: TBD
Hose Clamps: WRC spec constant tension hose clamps

Fuel System
Injectors: Deatschwerks 600cc
Fuel Pump: TBD. N16 runs similar config pump as the GC8 Impreza WRX
Fuel Pressure Regulator: Tomei
Fuel Rail: GT Auto
Stainless Braided Hoses with AN Fittings

Induction System
Throttle Body: Currently stock but who knows
Intake Manifold: Currently stock but who knows. The Golden Eagle prototype on Vios Turbo looks dangerously tempting.
Intake Manifold Spacer Kit: Outlaw Engineering
Airbox + Air Filter: ITG Maxogen if budget suffices else it'll be K&N

Engine Management
ECU: Haltech but then again Bro Mr Vios Turbo is now playing with Autronic. Tough call!
Wideband O2: TBD

Engine Builder - GT Auto

After months of research and discussion I've finalized on the Slowtra's engine builder. The Slowtra's engine will be build by GT-Auto. GT-Auto is responsible for many of the monsters I know including the SP, Lemon and of course a certain Toyota Vios Turbo. You guys know who you are :) GT-Auto is also responsible for the fastest 8 sec drag Evo in the Bolehland Motorsport Scene. These guys are the real deal.

I cannot wait to get started on the collaboration work as unlike most fast N16s here the Slowtra will have the supposedly inferior QG16/18DE engine and not SR16/18/20/DE/VE based. QG actually stands for "Quality" and "Green" so you can imagine what the original brief of the engine was. However all this is going to change soon. Stay tuned for 2011 the year the Slowtra is no longer slow.

More Early Christmas Presents: Stoptech 309 Compound Street Performance Brake Pads

Arrived home after a long day's work today to find this box sitting in my compound.


Unpacking the box revealed some spare parts for the Slowtra and my performance rear brake pads. These are the new Stoptech 309 compound street performance brake pads which I ordered from G Spec Performance the same place where I got my braided clutch line. Picture below of the pads and what's left of the original box for the brake pads.

The original box has been discarded to make the package Bolehland Customs friendly. Picture of the backing plate complete with noise reduction shim.

Friction surface

I originally wanted to get Hawk HPS but was adviced by Greg of G Spec that the Stoptech is better as he had been running these for a month and the fade resistance is much better, they stop great on the street, and still stop well when hot. Comparison data provided by G Spec:

• Stoptech 309 suitable for usage up to 1300 degrees Farenheit (704 deg Celcius) - light track, autocross, canyon runs, performance street). HPS showed significant fade at 750 degrees F (398 deg Celcius)
• Stoptech 309 has 25% more cold bite than HPS
• In an industry standard brake fade test, HPS experienced significant fade after the 3rdstop. Stoptech 309 had more bite after our 15th stop than HPS on that 3rd stop.
• Pad wear was 50% less after the test was completed, shows much better durability, especially at high temperatures
• Stoptech 309 come pre-shimmed for reduced noise, HPS do not include shims.
• Stoptech 309 pads are pre-scorched for reduced green fade and more consistent performance, HPS are not.

Best of all the Stoptech 309 Street Performance pads cost about the same as the stock Hitachi brake pads and less than the Hawk HPS. And what about Endless? While these look nice with the blue backing plate the price is really nuts especially when you consider these are only rear brake pads. Even basic Endless SNP compound pads cost significantly more than the Hawk HPS.

So is the Stoptech really that good as it is made out to be? I will report out in about a month's time when I install together with my DBA 4000 Series rear brake rotors which hopefully are in a cargo ship on its way to Malaysia by now.

Dietary Supplements Part 3 - Ti Bolts for Alutec Strut Bar

Sometimes I don't understand aftermarket performance parts manufacturers. Why go through all the trouble of manufacturing the entire strut bar from aluminium including the mounting bracket only to fit everything together with el cheapo mild steel fasteners? While my Alutect front strut bar looks as good as day one the same cannot be said of the fasteners which attach the bar to its mounting brackets. Despite lots of TLC these were beginning to rust! I was just going to settle for some stainless steel items as titanium versions will cost nearly as much as the bar itself from my previous experience. However three factors caused me to eventually go for Ti. Number 1 the UK Pound is at an all time low against the Malaysian Ringgit, number 2 Pro-Bolt had the specific sized bolt I was looking for on sale and number 3 I had two leftover Ti M10 washers so this meant I only had to order two washers instead of four. Talk about luck! Apart from being lighter than steel titanium like aluminium also does not rust.

Picture below of the stock rusty fasteners with the Pro-Bolt titanium equivalent

Closeup of the "stock" nut which was beginning to show spots of rust.

Took me bout 15-20 minutes to DIY install the Ti fasteners. Picture post-install.



When budget is avail I'm going nutty and replacing the three nuts that mount the top of the front damper to the suspension strut tower with titanium equivalents. Will need six nuts for that though..

Early Christmas Present: Works Bell Rapfix II Steering Quick Release and Short Boss

My wife came back from her working trip in Japan with a nice box.

Opening the box revealed the following 2 items - Works Bell Rapfix II steering wheel quick release and short boss kit.

As mentioned in my earlier post I was working with The Tuners Group in Australia on the short steering boss application for the Slowtra. So how did the parts end up in Japan? Well it turn out that while The Tuners Group is one of only two authorised Works Bell Factory Authorised National Distributors outside of Japan but most importantly they also have warehouses in Japan and the capability to ship within Japan itself. This means that I pay The Tuners Group prices for the Rapfix II (believe me its even cheaper than buying in Japan itself as I contacted several Jap contacts to confirm. I am getting the Rapfix II for bout AUD299. Retail in Japan is 31,290 yen) and also save on the shipping costs. Only cost me approx RM30 to ship to my wife's hotel in Tokyo.

Picture below of the Rapfix II components. This is my second Rapfix II with the first being used on the SP. You can read more about that here. There is no play and the feel and quality is second to none. For the SP I had a red body/silver sleeve Rapfix II but this time round for the Slowtra I decided on an all black unit.

Here's a closeup courtesy of The Tuners Group website

Please note this is the real deal and not a rip off. You know which rip off companies I'm talking about as they are widely available here. Works Bell hold numerous patents including the patent for ball lock quick release systems which they received back in 2001 but they have not I repeat Have Not licensed this technology to any other company.

So why did I decide to get the real deal? It's not only because of the branding. The steering wheel and steering system is a critical component of a car and there can absolutely be no quality or strength tradeoffs. Imagine having play in your steering when you're attacking a tight hairpin or worse still having the steering wheel come out completely. Instant disaster! The Rapfix II features a plug and socket made from high strength A5056 alloy which is then heat treated to H34 standard to increase yield strength of the metal by 60% and then cold die forged. For comparison sake consider a gravity cast wheel/rim strength with a forged version in terms of strength and weight. The Tuners Group also clearly explains the materials used and manufacturing technology here. SUS304 stainless steel springs, SUJ ball bearings and SUS XM7 stainless steel cap screws are used to assemble the Rapfix. The problem with knockoffs is that while it may look similar to the real deal you cannot determine the exact composition and strength of the alloy being used nor can you determine manufacturing process simply by looking at the product.

If I recall clearly 4+ years ago everything was in Japanese but now there is also a nice installation instruction clearly written in English.

Installation details and post to follow once I determine my steering wheel. Having used the Momo Monte Carlo and Model 78 previously I am now deciding if I should try something else. What steering wheel I use will also be determined after discussions with my tuner. I'm dreaming about having ECU map selector button on the steering itself or datalogging functions or... Better stop here. While mine and the standard version of the Rapfix II has 2 electrical contacts a new 4 contact upgrade is now available. Stay tuned.

Excellent Customer Service - The Tuners Group

I've been thinking to ditch my airbag steering wheel and get something proper like the Momo Corse Model 78 I was using on my previous car together with a quick release boss. Or maybe my carbon fetish will lead me to a Reverie pre-preg carbon steering wheel as used by the WRC teams? Nothing beats a proper "race" oriented steering wheel for feel.

I wanted a proper Works Bell shortened steering boss as using one with a longer length together with the Rapfix II meant my fingers couldn't reach the indicator and light stalks without me reaching forward.

Now the problem here is the N16 is not exactly available in Japan. I contacted The Tuners Group in Australia as they claim to offer the Rapfix II cheaper than retail in sushi land. I initially didn't hope for much but after exchanging some data for my car including the proper chassis designation for the equivalent model in Japan (The Bluebird Sylphy G10) they actually found the correct boss kit for my car and put in on their online web shop. So much better than the typical "I'm sorry but we do not have an application for your car as it is not sold in Japan" response. A big thumbs up!

Will blog more later after I order the short boss and Rapfix II.

Clutch Hose Evolution

Piccie from Bro Mugil on my evolved clutch hose with shorter hose length and alloy AN end fittings which he sourced for me from Down Under. Unfortunately only one end (the banjo end) is avail in aluminium. I think I am suffering from OCD :)

My Rims and Tyres are for Sale!

OK. This is it! I've decided to go for 17 inchers and selling my Gram Lights and tyres. Details of my rims/wheels here. My tyres are Michelin Pilot Sport 3s in 205-50 16" size. Tyres have been used for only 5000km+ only. I can sell the rims and tyres separate. Serious enquiries you know how to reach me. No low ballers please.

Larger Wheels - Work Emotion CR Kai

Another wheel available for my PCD and wheel lug configuration, the famed Work Emotion CR Kai. These are now low pressure cast and no longer forged. About a kilo heavier than a FN01R-C for 17" X 7" and more expensive unfortunately. Looks great though.

Larger Wheels

I'm starting to think if I should go to larger wheels or rims to contain the power that I'm building the Slowtra to produce (>2 times)? I really hate wheelspin as all that energy and power is wasted in heat, smoke and noise. I'm thinking if I should go for 215-45 series tyres on 17" X 8" or even fatter tyres on 17" X 9" wheels? This should clear the big brakes nicely too. On the other hand there are also camps advocating stretched tyres for a stiffer sidewall feeling.

The problem is N16 comes with fashion obsolete 4 lug 114.3mm PCD. While this might have been fashionable more than ten years ago when the likes of Evo 1-3 roams the streets nowadays all 114.3 PCD are 5 lugs. What this means is that most rims are meant for that configuration. Thinking if I should convert to get the wheel I want? The 114.3 PCD 4 lug option is extremely limited but here is one nice example still in the market. 5Zigen's FN01R-C "Hot Version". The are relatively light for a cast wheel but I still dream about forged Rays TE37s.

So my choices are stick with what I have (16" X 7" Rays Gram Lights), go for larger sizes and convert to 5 lug or stick with my current wheel mount config and get something like the FN01R-Cs. What do you think? I know what some of my close brothers will say :P

Brake Master Cylinder Breakthrough!

Remember my horror and disgust on finding the puny size of my brake master cylinder? Well the good news is I've found the correct part number courtey Nissan 4U.com. Now I just have to bite the bullet, source, order then hope it fits and works. Cap Saw says its a 99% bolt-on!

Part number for Nabco 15/16" Non-ABS brake master cylinder is 460105M422. Check your master cylinder properly to ensure it is a Nabco. Nissan uses two BMC suppliers - Nabco and Tokico. The parts between both makes are NOT interchangeable.

Slowtra's Rear Brake Pad

I've completed my rear brake pad research and ordered my rear pads. Picture below of  my rear brake pad's backing plate complete with noise reduction shim.

The brake pad I'm using is different from regular TCM N16 1.6 SG-L and XG-L Sentras. Thanks to Nissan parts sharing the brake pad is the exactly the same as the USDM B15 Sentra SE-R with SR20DE engine and the famed JN15 Pulsar VZR N1. Brake pad drawing courtesy of Hawk (Pad Shape HB421)

and Endless (Pad Shape EP263). Measuring my stock pad with a vernier caliper confirmed the dimensions.

Sharing the same brake pad with a performance car has its merits. For one there are lots of brake pad options. Endless lists the following compounds for the EP263 - SNP, NS97, SS-Y, SS-M and CCA.

And what about the local disc brake Slowtras? I believe it should be this pad shape from my eye balling. Pls note that this is from eye balling only as I did not have the opportunity to dismantle the rear brake pad of local TCM Slowtras for measurements and verification.

This pad is apparently also the same as a Mazda RX8. The total pad surface area is slightly less than my pad as the max height is ~3.5mm less.

So did I get Endless or Hawk or? I'll save that for another story when my brake pad arrives

BorgWarner EFR Snail

Those of you whom know me well will know I am an "NA Bagus" kaki. However this new turbine is making me excited about turbocharging something which I've not been for a long long time. Very excited. More details here:

http://www.full-race.com/articles/borgwarner-efr-turbos.html
http://www.motoiq.com/magazine_articles/articletype/articleview/articleid/1750/borgwarner-efr-turbo-feature-set.aspx

The EFR is claimed to be the most responsive and fastest spooling snail in its range. Bye bye turbo lag..

Slower-Phy?

I had a chance to take some quick snap shots of the Sylphy when I was @ TCEAS doing my rear disc brake and beam conversion. This is what happens when the major criteria in a car's design is NVH, comfort, cost and less cost.

The G11 Sylphy rear beam. The much maligned Scott-Russell lateral link fitted to the N16/G10/B15 is MIA which is a good thing for starters. The beam, arms and shock absorber mounts are all in one piece and integral with the beam. Can't do much here in terms of adding aftermarket anti-roll bars and chassis bars. Any upgrade on stiffness would mean upgrading the entire beam assembly. Ouch!

The lines in blue are hydraulic brake lines. Closeup of the hydraulic brake lines. The trailing arms have a bend so Nissan had to mount the brake lines on the straight beam itself.

Holy cut-outs on the beam Batman! Got flex?

No these are not reversed super aero brake cooling ducts but merely the platform to locate the rear coil springs and damper/shock absorber.  The Sylphy is the only current market 2 litre car still on rear drum brakes. Some 1.5 litre cars have better rear disc brakes.

Here's an ESM picture of the G11 rear beam and suspension. Don't ask me where I got it from :)

These are bout the pictures I managed to take. Other "interesting" design decisions include: PCD denoted Pitch Circle Diameter and is the distance between 2 opposite wheel or rim lugs and is a good indication of wheel bearing size and hub or upright stiffness. The Japs have settled for 2 sizes. 100mm PCD 4 bolt pattern for smaller cars (A and B segment ie. Myvi, Vios, City)  and 114.3mm PCD with 5 bolt pattern for larger C and D segment cars (Civic, Altis, Lancer, Accord). The 2 litre Sylphy is approaching D segment in size but uses the 100mm PCD 4 bolt pattern. Erm. Obviously the designers are not worried about caliper piston knock pad under performance or track driving conditions. Stop Tech has a good explanation on what piston knock back is here.

And finally (I forgot to take a picture but you can check it out on the web or better still go ask a TCM salesman. I am very interested in the answer) the Sylphy's speedo goes to only 190km/h max. JDM meters on a Bolehland car? I find it hard to believe. When I asked my TCEAS technician he just shrugged his shoulders and mentioned "CVT". You make the judgement. I admire the frankness and honesty.

Interestingly Impul in Japan (not the MYDM ripoff) has a 170hp engine package including throttle body, cams, pistons and even ECU upgrades. You read it from me first here. :) While the MR20DE engine like any other modern 2 litre engine shouldn't have an issue with such a power output I would really like to see how the flexi, truck like suspension and CVT gearboxed Sylphy cope with the additional power and stress. The brakes are also going to have a field day! As I mentioned in an earlier post, what a crying shame from the same company that spawned the 200ps 1.6 Pulsar VZR N1, Skylines, Sylvias and now R35 GTR. Bolehland Nissan performance driving enthusiasts deserve a better car!

MYDM N16 Manual Transmission Horror!

I mentioned in an earlier post that the Slowtra's gearbox model is the RS5F70A. This is because the European Nissan Almera N16 ESM (Electrical Service Manual) states this particular gearbox for both QG16 and QG18 engines. Well I was Wrong!!! At least for our dear Bolehland domestic market 1.6 manual Slowtras. Here's why I say so.

Picture below of RS5F70A gearbox from Euro N16 FSM

Picture below of the RS5F30A gearbox used by Euro N16 Almera 1.3, 1.5s and the Proton Saga BLM. Yes the Proton Saga uses this same gearbox.  Don't believe so? Check here.

Below are actual pictures of my gearbox.

Here's a hint. Count the number of bolts on the case cover (red box). The RS5F70A has only 5 bolts. The RS5F30A has 6 bolts. My gearbox has 6 bolts. Does this mean my car uses the 30A gearbox? Well I'm still not sure but having seen lots of pictures online of 70A boxes I'm 101% sure it definitely ain't the 70A. The number of strengthening ribs around the driveshaft appears to be different from the 30A from what I can see on my box versus the ESM. Aichi Machine Industry also list another gearbox used by Sentras (not stated which model or gen though) called the F52A but that has 6 gears and is likely used by USDM B15s.

One joker in Autoworld forum even told me to go ask the technicians in TCEAS. Like I haven't asked before desperately trying the local forums. D'oh! Well the technician in the TCEAS spare parts centre which I usually go to didn't know and asked me to go ask the service technician. Which I immediately did so only to be told to go ask the spare parts centre. When I further probed the service technician he said he didn't know and that he wasn't familiar with manual Sentras. Most customers are auto! All this from the largest TCEAS in Butterworth. Err.. Think I better stop here. Oh and they (the TCEAS technicians) don't wear white uniforms. What a joke! I just wish I can get hold of the parts catalogue and ESM for MYDM TCM N16s.

So why am I so preoccupied with what gearbox I have? Well the 30A gearbox is rated to a max of 150Nm of torque and the 70A gearbox 200Nm. So you tell me which gearbox is stronger and able to withstand the rigors of positive crankcase pressure? On top of that there are plenty of LSD (no not the drug) options available for the 70A. I am now on the lookout for a good to excellent condition preloved RS5F70A gearbox. There's also the other matter of whether the 70A box and mine are sharing the same mounts. Might have to source for that too. Bummer!

Black or White? Ultra Racing Front 4 Point Lower Arm Bar and Room Bar

These arrived together with my rear beam but I simply ran out of time. Besides I didn't really dig the white powder coating. White is about the worse colour for something meant for the bottom of a car and exposed to all the road grime, dust, dirt and anything else you can think of.

The lower arm bar is as its name implies, ties the front lower arms for a more rigid assembly. So why is rigidity so important? Well anything that flexes too much including a car's chassis, bushes, tyres, etc. becomes a sort of a spring by itself except that unlike a car's suspension system this spring is uncontrollable which is not good for handling. Per Mike Kojima "The lower control arms front mount in our car (N16/B15) hangs out in space unsupported. This causes the lower control arms to move under hard cornering load causing steering inaccuracy and tire contact patch loss."

The room bar is the bar linking both the B pillars behind the front seats and also serves to improve the car's chassis rigidity.

All Ultra Racing bars are made from steel as opposed to lighter aluminium. Ultra Racing claim via its website that all brackets are 4mm to 5mm steel while hollow steel tubes and oval tubes are 1.2mm to 1.6mm thickness. Ultra Racing also claim that as steel is stronger than aluminium for the same size and thickness and that in order for aluminium allow to be as strong as steel it has to be at least double the thickness thus the weight saving is not so apparent anymore. You be the judge but I know which material I would prefer if I had the choice. Let's just say that the top Japanese manufacturers such as Okuyama Motor Sports aka Carbing offer their bars with aluminium alternative.  

I have sent my Ultra Racing bars to be painted matt black and should get them back for installation in about a week. Stay tuned.

Clutch Hose Upgrade - Installed

I had my G Spec Performance braided clutch hose installed together with my rear beam and disc brakes. The clutch hose is meant for the QR25DE but fits the QG no worries. The only difference from stock is the longer length which is not a problem. Picture below of stock clutch hose.

The airbox had to be removed to facilitate installation of the clutch hose. Picture below of the installed braided clutch hose

A teflon hose with stainless outer braid is not as flexible as a rubber hose necessitating a longer length. And make sure you properly bleed the hydraulic clutch cylinder after changing the hose. My Motul RBF600 brake fluid also doubled up as clutch hydraulic fluid. I'm thinking of sending my stock clutch hose to an AN fittings and braided hose supplier for replication complete with aluminium alloy end fittings. Any takers?

Brake Upgrade Part 1 - Rear Disc Brakes and Beam Upgrade

Going fast is not only all about building horsepower. A car will also need to be able to stop as well if it is not to turn into a flying coffin. By some strange logic TC decided to equip the second or arguably the fastest Sentra variant in Bolehland with rear drum brakes. Drums are cheap to manufacture and the brake shoes are even cheaper. However they're mostly useless for hard and performance driving on something as big and heavy as the Slowtra. I decided to upgrade the rear brakes to disc brakes as the first part of my brake upgrade.

The rear beam on drum braked N16s do not come with the mounting bosses for the disc brake caliper so to upgrade to rear disc brakes one has to either try and weld the bosses on the beam itself or source for a used beam complete with rear disc brakes. I did try the third option which was to buy everything new but TC wanted to charged me in excess of three thousand smackers just for the beam alone and we haven't even started talking about the calipers, rotors, etc. Clearly going for a used beam is the only economical option. Oh and here's what you need for a rear disc brake upgrade:

1. Rear Beam from an N16 variant complete with disc brakes (caliper, brake rotor/disc, pads, brake hoses), axles, hubs, etc. The complete assembly. Even the dust boot on the drum is different from the disc brake so hardly anything cept the some bolts are reusable. I've decided to upgrade my brake hoses to PRO-RS items. Everything else is stock Nissan
2. Rear handbrake cables. The drum and disc brakes use different handbrake cables.
3. About 1 litre of brake fluid. I'm using Motul RBF600

It took me quite some time, ok more than 2 years in my case to finally find a decent condition rear beam.  Blame that on other life priorities. TCEAS in Bayan Baru did managed to source for me a beam two years back but that didn't really fit my grade. The calipers and pads are all stock items. No point going for performance items yet as I'm on stock front brakes and upgrading to rear pads with a higher coefficient friction will just spoil the braking balance. Besides I have part two, three, etc. to write :)

Pix below of my rear beam after unpacking. Even the service centre manager helped to unpack the goods. Thank You Sir! The beam has been repainted and likewise the calipers. I choosed silver for the calipers for the oem look. Don't really dig ricey red. The long dangling things are not "tentacles" but are the handbrake cables.

I also had my "works engineer" who sourced me the beam to upgrade the stock bushes on the beam trailing arms to Superpro items. Thank You Ah Tiong (Hoong Hooi Motorsport). Ah Tiong even painted the calipers when his regular painter declined due to "too much work". The stock bushes cannot be physically removed from the beam as its shell had to be reused for the Superpro. This means using a burner or welder to burn away the bush. The shell was then spot welded to the trailing arm and the Superpro bush fitted. Pix below of the Superpro rear beam trailing arm bush.

So why all the hassle on the bushes? Picture below of the stock rear bush tells the whole story.

The stock soft bush is great for NVH as it allows for lotsa movement in all planes but this detrimentally impacts handling during hard braking and side load (cornering). The Superpro minimizes this. There is also the harder 90 durometer Superpro bush if one aspires to build and all out race car like the Dog III. I'm using the standard variant part number SPF1942K. The harder variant is SPF1942-90K. If you're interested in the bushes please contact me.

It took most of the morning to remove the stock beam. The exhaust heat shield had to be removed to access the handbrake assembly.

The PRO-RS rear braided brake hose installed to the caliper first. The mech managed to install the hose at the wrong side despite clear labels marking which side and which end. Luckily I spotted the mistake.

 
These are the ABS sensors for the rear wheel. Since the Slowtra does not have ABS these were removed. Per my TCEAS technician my beam's JDM as these use a different sensor compared to the MYDM N16 Sentra. There are two sensors (one per side) and part of the cabling is secured via brackets to the beam trailing arm.

The sensor goes here if  you're curious. I just grabbed a socket wrench quickly to help the mech to remove.

Picture below showing the drum brake beam vs the disc brake beam

The disc brake beam actually has a larger diameter compared to the drum brake beam. 65mm vs 55mm. IMHO the disc brake is able to generate more load and stress to the beam hence the need for a stiffer and stronger beam .

Picture of below of the beam installed on the Slowtra together with brake hoses.

Rear caliper and rotor.

All MYDM N16 and USDM non-Brembo equipped B15 variants run a 258mm diameter X 10mm thick solid rotors with same pad shape and size. Rear caliper has a single piston of 33.96mm. Compare this to the drum with a 203.2mm inner diameter and 17.45mm single piston. Clearly my stock 7/8" master cylinder is maxed out! Luckily brake pedal travel is not compromised and pedal feel is excellent with the PRO-RS braided brake hoses. Took quite some time to properly bleed all the brakes as I also had my front brake hoses upgraded to PRO-RS items. These might not stay too long on my car though as I have other plans for my front brakes.

Here's how the rear disc brake looks behind the wheel. Took the entire day to install and bleed the brakes. I also installed my braided clutch hose and changed the Slowtra's engine oil and oil filter.

Driving back home the improvements were immediately very obvious. The rear end felt more firm and planted. The brakes were so much better in terms of feel. Better stopping power was also noticeable. I'm not done though. I have a DBA 4000 series rear disc on order which should be arriving from Down Under in January. Have not decided on what rear pads to use yet. There's plenty of choices avail from EBC to Hawk to Carbotech so no worries there. And why am I only talking rear brakes when an FF car requires 70-80% front braking action? What about the front brakes? My front brakes pads are on its last legs but I'm not changing coz I'm planning to revamp my entire front brake config. And I mean it. Please be patient for Part Two and Three. I promise it won't take two years :)