Wednesday, June 29, 2011

Ed's FJCruiser 4 link Transformation















After months of work, we drove the FJ for the first time yesterday. We are very impressed with the handling and drivability of the whole package. Ed's Toyota is truly the nicest, cleanest, best performing piece of 4 wheel machinery that Krawltex has ever built.

The new stainless rear brakelines do wonders for the stopping power. Now the rear disc brakes will actually lock up before the TRD/Brembo upgraded front brakes. Ride quality wise, the rear 2.5x12" King coilovers and triple bypasses are matched perfectly to the 12" of front travel the Total Chaos/King combination provides. Whether it is a hard launch off the line or throttling acceleration in a turn, the 4 link geometry and Anti-rock sway bar plant the suspension firmly to the ground without any signs of body roll or dive.

To re-cap what this incarnation was about, let me explain what all had to be done to match the quality of the front end and the problems that had risen from building the drive train up. First off, a TRD Supercharger with a bigger boost pulley and fuel management system, coupled with 35's and 4.88 gearing equates to a blown up rear Toyota axle. What was chosen to replace it was a hybrid axle, a first of it's kind. Before we began this project, we installed a Rockjock 60 in to another FJ Cruiser. What we didn't care for was how tall the rear axle was with a link truss, and what we had to notch out of the frame to make that package fit.

Instead of what many shops (including ourselves) had already installed, we enlisted Currie to take the same axle flanges and weld them up to a custom 4130 chromoly Fab9 housing that was 2.5" wider than the axle it was replacing. This was the essential component to a street legal axle swap because the outer axle flanges Currie developed allow the use of the factory brake backing plate with all of it's ABS/traction control glory. Hi9 was chosen for a 4.88 geared nodular center section and ARB locker. Currie cut the custom length 35 spline shafts. These were the biggest we could package and still utilize the factory brakes. The traction control and ABS are exclusive to the FJ Cruiser and will light the dash up like a Christmas tree if anything is out of the computer's specifications.

Suspension wise, we went with the traditional 4 link with triangulated uppers. Chromoly heims with 1 1/4" lowers and 7/8" uppers were chosen. It's riding on mock-up links while the Heretic Fab heat treated chromo links are still in the hardening process. Downsouth Motorsports (our go to guys for shock building), suggested the 12" body coilovers and bypass shocks with what seems to be the perfect spring rate right out of the box. As mentioned before, it matches the front suspension travel to a tea. We contemplated ways to radius or notch the factory frame for clearance. What transpired was chopping the rear frame completely off the truck, behind the middle body mount under the rear door. 2x6" square tubing was hand cut in to frame rails that not only radius upwards in to the wheel well and down to the factory rear cross member location, but also curve inwards to provide ample clearance for shock packaging. Coil over hoops go through the floor with frame bracing inside and outside the cab. A Currie Anti-rock sway bar plants the rear tires. All of the adjustable link bracketry, arm mounts, axle truss, and shock mounts are 1/8" chromoly stacked plate, TIG welded of course.

All of the sexy suspension could not have been performed without addressing the fuel containing situation. Many people perform 3 link suspensions with a pan hard bar under these Toyotas, because the factory gas tank sits on the driver's side inner frame rail. We wanted this truck to have the best ride and most travel, without sacrificing flex. So Fuelsafe was enlisted to build a custom cell. What makes this cell so special besides the Fuelsafe monicker, poly bladder, internal baffling, and aluminum shell? Another first of its kind, our fuel cell has a modified top plate to adapt the OEM Toyota sending unit/fuel pump assembly. We chose this route so the TRD Supercharger/APR X1 fuel management system could keep it's very specific fuel pump AND we could use the factory in dash fuel gauge without the need of adding an auxilary unit. The whole package is enveloped in a 1x1" steel cage, then shod with a 3/8" 60/61 aluminum shell.

This truck is a complete Beast! It has custom touches from head to toe. The ride quality is second to none and the FJ is a complete blast to drive. To reflect upon all of the mods which have taken place at Krawltex... Here's a short build list of this project: 2.5" wider per side Total Chaos long travel suspension w/4130 axle shafts, A-arm gussets, King 2.5" coilovers and triple bypass shocks, limit straps, chromoly upper/lower A arms with uniballs and aluminum skids, knuckle gussets, steering extensions, TRD Supercharger with APR X1 fuel management/7th injector, cam gears, and smaller pulley for more boost, Doug Thorley long tube headers, 02 Simulators, 2.5" madrel exhaust TIG welded, Lefty 4.1 t-case w/twin stick, 4.88's and ARB in the front, Currie chromoly 9" w/Toyota end cups to utilize factory brakes (for ABS), Krawltex built triangulated 4 link, 1 1/4" and 7/8" chromly heims, chromly heat treated links, 2.5x12" King coilovers and triple bypasses, Krawltex built rear frame, Fuelsafe custom cell to utilize OEM Toyota fuel pump, Fab fours bumpers and rock sliders. We also chopped all the factory crossmembers out of the truck and flush mounted them with the factory frame rails. Then we built 3/8" 60/61 aluminum skid plates from the front bumper back.

Last step is an interior cage, custom dash/gauge work, and possibly an aluminum rack system. But we are going to take a breather and let Ed enjoy his truck for a while! I will finish off the exhaust today while Chris works on interior paneling. Here is a link to the current 4 link build and here's a link to the entire NEWARE FJ BUILD