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.