I just have to throw in my results of the three years of research on the turbocharger exhaust housing testing that I did for A. W. D. Back in the day, everyone was just going along with the 16cm housing and that was it. Then a few guys were taking a 12 housing and "modifying" the wastegate and getting massive low end power from the combination of the 12cm housing and a big set of nozzles. I too joined the 12cm testing and due to the intense fueling and resultant high drive pressure and increased cylinder pressure, head gasket failure occurred. In looking at the head gasket, it looked as if it went through a war with breaches in the gasket between the cylinders and the water jackets. Upon putting the engine back together after lowering the compression to better suit the power and boost the engine will be sustaining, I went with the 14cm housing. Still had pretty good low end power, but the engine was not up to snuff in the higher rpms. Not a week later, I tossed the 14cm housing into the collection of old housings and bolted back on my 16cm housing and with the OEM turbo it was by far the best combination for the 370B injection nozzles in the testing. My 7000 lb truck was pulling 15. 5 second times at 92 mph in the quarter mile on all terrain tires with the transfer case in 2 wheel drive. The 16 housing also is helpful in reducing egts and drive pressure, which will add reliability and help keep you from having to pull the head off your engine (or even worse pay someone to do it for you). I still was running with hp figures in the 500 range, which is out of the efficiency band of the 16cm housing on the HX35 turbo. Piers at BD was just at the time testing the HX40 18. 5cm turbo and I immediately ordered up the first one he could send out my way. Boost went up from 45psi to 50+psi, power shot through the roof, and egts came down to almost respectable limits. Quarter mile times stayed the same, however, in spite of the fact that I was spinning the rear wheels even in fourth and fifth gears. Mph came up to 97 mph at the top end of the track. The HX40 18. 5 turbo also reduced the drive pressure significantly and I have no problem pulling any trailers, nor do I have any turbo lag problems that I have read about in similar postings over the past few months. I hope this is useful in helping you make the decision.
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Chris Timochko
AUTO WURKS DIESEL R&D TEAM
1997 5sp 4X4, Rhino Linings, Espar Heater, A. W. D. HX40 turbo, ATS 3pc Manifold, BD 4" Brake, Marine Compression, A. W. D. Custom Tuned Injection Pump, A. W. D. Intercooler, A. W. D. 370B Injection Nozzles, Delivery Valves, Governor & AFC Spring Kit, Psychotty Air, A. W. D. Water Injection, NOS Diesel Kit, A. W. D. 6" Chrome Exhaust System, BD No Smoke Valet Switch, McLeod Dual Disc Clutch, Mag-Hytec Rear Cover, Cummins Chrome Kit, Optima Red Tops, Hadley Bully Horns, Hurst Line Loc, Goodyear Wrangler AT/S 305/70/16s.
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Project U96 - 1996 3500 2WD racer. A. W. D. Marine Ultra Low Compression, A. W. D. Teflon-coated Pistons, A. W. D. High Lift Camshaft, Ported and Honed Cylinder Head, Intake and Exhaust manifold; A. W. D. HX40 Turbocharger, ATS 3pc Exhaust Manifold, A. W. D. Water Injection, A. W. D. Custom Fabricated Fuel System, Race Spec A. W. D. /BD P7100 Injection Pump, A. W. D. Custom High Flow Fuel Injection Nozzles, BD Auto transmission and Custom TC, Weld Draglites, Goodyear Eagle Drag Slicks, 5" Single Stack Through The Bed, Mag-Hytec on Rear and Transmission.
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