If the actuator is not adjusted properly, you will get a lag in power. For example, the actuator is supposed to start pulling your vane lever down at 3-5"hg, but if it is not pulling down until 8-10"hg, then it will take a second or two to get to the boost your looking for. MAF data should read 800-1000 when WOT. There's kind of two questions here. If you're asking how much boost is safe for a stock turbo, then BB has the answer 18psi or so. If you're asking how much boost you can run before you have to beef up a stock ALH block, around 28-30 psi. Any more and you'll need better rods, girdles, head studs, etc. D. Here's a tidbit for anyone else out there the likes to over-engineer their projects and work out all the details: Dry weight of a 1.9 TDI (AHF) with AC and DMF (but no clutch) according to my digital scale is 361 lbs. See pic for exact configuration. Last edited: Dec 13, 2012. VNT-15 should sustain 18.0 max. and spike no more than 21.0 PSI in a typical 1,500RPM-redline 3rd or 4th gear test. 28 PSI for 17/22? Seems a bit high. 26 PSI sustained was recommended by the original VNT-17/22 distributor a little while ago, and even that's a little high. 28 PSI is also close to the limit of 3 bar MAP. Volkswagen 1.9 TDI ARL engine 4 - Cylinder Turbo Diesel unit 1.9 L4 8v Turbo. Diesel. Data. Engine info Volkswagen 1.9 TDI ARL displacement: 1896. cc. configuration: Frank's VW TDI's, LLC. 1007 Olive St. Lockwood, MO 65682. Fax or Ph: 417-232-4634. But personally, I would jump on that used engine. Throw in a cam and set of lifters (very reasonable) and a new timing belt kit and that engine will be ready to go for another 200k miles or more. Last edited: Oct 22, 2009. D. 1.9 TDi tuning causes more heat build up, the turbo works harder, and the driver is expecting much more from the engine. An intercooler that is well-designed can give you 5% to 10% more power from your mods, and resist heat soak for a longer time. Guidelines for Higher-Boost Applications. To run boost levels from 6 to 10 pounds, Weiand recommends the following: Forged blower pistons with a static compression ratio of 7.5:1. Steel crankshaft. Four-bolt main caps. Steel harmonic dampener. Stainless steel valves. Three angle valve job to promote better cooling. SuWF.