BP Autosports Supra Slowly Coming Back to Life

[Alex L.]

It's been awhile since I've posted anything about the Supra on here. Since my last post, there has been a substantial redirection of the project in order to start the "final" stages of it for it to finally be "complete", which some of you may have seen on Facebook. These terms are laughable to consider when thinking of a project car, but I'm reaching the end of what I'll be able to do with my budget, time, and ability to compete.

 

While the turbo remains the same 94mm that I had posted about previously, virtually everything else pertaining to the turbo system has changed. I decided to switch to a 2JZ-GE fixed cam head as opposed to the 2JZ-GTE fixed cam head I had previously planned to use, which necessitated a new header and intake manifold. As many of you know, I build exhaust manifolds, and I wanted the header for this setup to be something special. The vast majority of turbo headers/manifolds on the market are constructed of 304SS schedule piping, which gets the job done. The next step is 321SS, an alloy of stainless steel with titanium and nickel added to its structure to increase its corrosion resistance and resistance to thermal fatigue. This, in turn, allows a header/manifold to be constructed of thinner material without sacrifices in longevity.

 

The ultimate alloy to use for this application is Inconel, a nickel alloy used in upper echelon motorsports, aerospace, and industrial applications due to its extreme resistance to thermal fatigue and corrosion. This translates to the ability to build a header/manifold out of the thinnest material possible without sacrificing longevity. I chose to construct my header out of 0.049" wall Inconel 625, the most commonly used Inconel alloy in motorsports, and the easiest to obtain and work with. As with any material, it presents its own unique characteristics and challenges when working with it, but, once the learning curve is conquered, it's a joy to craft with. My header is of stepped tri-Y construction with dual slip collectors used throughout. It's flanged for PTE or Garrett promod turbine housings, and holds twin Turbosmart Pro-Gate 50mm wastegates. On the bottom side and not pictured are bungs for individual EGT sensors. The head flange, turbine flange, and wastegate flanges are stainless steel, as Inconel and stainless can be freely welded together, and sourcing or having custom flanges made out of Inconel would be a pointless use of money in my eyes. If memory serves correctly, the header weighs approximately 23lbs sans wastegates.

 

The intake manifold is a one-off piece I built for this application with materials from RMR, Race Part Solutions, and Sleeper Designs. It holds a Wilson 105mm throttle body with Wiggins provisioning on a flange I hand made. I have a bit more work to do on the intake manifold before it's complete in the form of an additional row of injector bungs, direct port bungs, boost reference ports, making the fuel rails, etc., but it's complete enough to be a place holder for the intercooler tubing for the time being.

 

The intercooler, while not easy to see in the photos, is a design that I've had bouncing around in my head for some time. It's common practice to use 0.1875" aluminum sheet to construct air tanks on intercoolers in high boost applications due to 0.125" sheet metal ballooning/rupturing under these conditions. Most intercoolers you see are either cut and welded sheet metal, or bent out of a singular piece of sheet metal with a press brake. Large flat surfaces are a recipe for an exploded intercooler, especially when constructed out of 0.125" sheet. I wanted to construct my intercooler out of 0.125" aluminum to save on weight while making it as strong as possible. My solution for this problem is to incorporate radii into both air tanks that will be pressure bearing, with strapping over the tank-to-core welds that should be the most likely to fracture under these conditions. In theory, I can use the strength of an arc to more evenly distribute the pressure load as opposed to building it out of cut and welded pieces of sheet metal, as I don't own a press brake to properly bend sheet metal. The inlet/outlet of the air tanks are flanged for Wiggins couplings, while the water tanks are constructed with -20 ORB bungs for the water inlet and outlet. The hot side air tank also houses my blow off valve, a Turbosmart Power Port. The core itself is a 6" Bell air-to-water core, very high quality and designed to be abused. The intercooler came in at under 30lbs for a 6" air-to-water intercooler, minus water, obviously, which I believe is respectable for an intercooler of this size.

 

The intercooler tubing, exhaust, and wastegate dump tubes are all made of titanium pie cuts sourced from Ticon Industries. I greatly enjoy working with this unique metal, and try to incorporate it into my car wherever possible. The exhaust is a 5" fender exit cut to the contour of the fender. The dump tubes are atmospheric and exit downwards rather than vertically, as I couldn't devise a way to bring them vertically without it looking poor. The intercooler tubes are 3" hot side and 4" cold side, and are complete with Wiggins flanges. All of the titanium is either polished or semi-polished, which I did to the best of my abilities on my Harbor Freight bench top buffer. I'll be adding color to the cold side components, but will leave the hot side components polished/semi-polished, and allow them to change color naturally as heat is applied to them. The wastegate dump tubes will receive gussets between them to prevent vibration, as well as allow for easy indexing of the wastegates when the car will inevitably be apart again. I have also built a 6" through-bumper air intake tube, capped with a 9" to 6" titanium velocity stack sourced from Mark at Proper Fabrications.

 

Engine management is a ProEFI Pro 128 system with as many bells and whistles were necessary. I purchased a RacePak drag logger dash to provide telemetry both real time and post-pass as a logging device. I purchased a set of four Motion Raceworks steering wheel mounted buttons and brackets to allow me to keep necessary functions (line lock, purge, bump box, and scramble, for example) within easy reach compared to the dangling switches that I had before. These buttons are aesthetically pleasing as well as ergonomically placed, checking the boxes of both my criteria for them. Wiring will be the next order of business, and I'll need to determine which switches, indicator lights, and accessories will be necessary to make the car function as I'd like.

 

My cylinder head is currently at Headgames awaiting Dave to work his magic on it. We're both very excited to see what possibilities there are with a 2JZ-GE cylinder head, and this should serve as a good test bed. I have a pair of custom grind Kelford cams that will be going in it in addition to Dave's valvetrain. The cams are covered with a pair of beautiful Autobanh Motorsports billet dry sump valve covers, as well as one of their billet coilpack brackets. The front of the head is occupied by a Sleeper Designs billet mechanical fuel pump bracket, with a Weldon 12.5gpm mechanical fuel pump, oversized for my eventual move to methanol.

 

Cosmetically, the car has nearly every carbon fiber body panel that can be purchased for these cars, including a Grannas Racing full-face carbon bumper and Paisley lip. I'll be purchasing a new carbon hood for it, as I cut my previous carbon hood to accommodate the titanium hood exit exhaust and wastegate dump tube during its last running iteration. I have yet to decide which style hood I'll be putting on it this time, and will most likely wait, as there are many more pressing matters at hand.

 

Steering and suspension have both been changed in the form of new IDS drag coilovers and a Grannas Racing manual steering rack. The IDS coilovers offer much more adjustment than the OG HKS Drags I had on the car previously, which should allow the Supra bounce to be tuned out of the car. The Grannas steering rack is much lighter than a factory steering rack, and incredibly easy to install.

 

I still have a number of components and systems to figure out and/or design for this setup (I.E. rear mounted radiators, fuel cell, etc.), and it's still some time from running, but it's complete enough to depict its overall form. I'm happy with the way it's came together thus far, and am excited to continue building this setup.

 

Now, after my rambling novel, on to the pictures:

 

 

 

 

 

 

 

 

 

 

[Doc1647545523]

A thing of pure beauty

[Forrest Gump 9]

Sorry, tl;dr

 

I thought your car was silver. Anyway, that’s some sick fab parts

[Cordell]

Sorry, tl;dr

 

I thought your car was silver. Anyway, that’s some sick fab parts

 

It is silver, has a carbon fiber nose on it.

 

Looks great Alex. Keep throwing pics up on Facebook I enjoy seeing what you’re working on.

[Geeesammy]

Looks awesome dude, great work as always

 

My $0.02, leave the turbo intake snout tube as is, with just the tack weld, looks soo sick and shows the craftsmanship that goes into getting that bend

[Not Brian]

tl;dr

Everything you see in the pictures is lighter and stronger than normal shit, everything else is top-shelf, Alex is awesome, etc.

[Robochan]

Hot damn. Looking amazing.

[BIGGU]

amazing work has gone into this. I still remember when it was just BPU!

[-Alex-]

Very impressive, glad to see you posting updates on it again!

 

For those of us not familiar with these, what made you decide to switch from a GTE to a GE head? I imagine with all the changes made necessary, there must be some pretty strong benefits.

[Alex L.]

Thank you for the kind words, all. In regards to the cylinder head switch, the GE heads are theoretically more efficient than the GTE heads.

 

When you consider volumetric efficiency, a forced induction engine has the assistance of a turbocharger, supercharger, or nitrous oxide to force additional oxygen into the combustion cycle, hence its name. A naturally aspirated engine relies entirely on its cylinder head's ability to flow air to accomplish an efficient combustion cycle.

 

In looking at the two heads next to each other, the intake ports on the GE heads sit higher than those on GTE heads, giving a better angle for air to enter the cylinder. The exhaust ports on a GE head are large, straight, and round, whereas a GTE head's exhaust ports are small, oddly shaped, and recessed oddly in the casting (primarily cylinders one and six).

 

While there is more work to be done to utilize a GE head in the form of deleting the distributor and figuring out a different way to have the CAS read, I believe the new head will be more efficient than the old one.

 

In theory, that is.

[DKilbourne]

Holy shit. That looks amazing.

[cstmg8]

Awesome project and beautiful work as always Alex. Can't wait to see this thing on the track.

 

Sent from my Pixel 2 XL using Tapatalk

[unfunnyryan]

 

[Alex L.]

Thank you, all. I'm excited to see it coming together as well.