Deboss Garage is building something special for Rob Ferretti’s 2018 YouTuber Project Car Showdown. The team chose a 1990 Audi V8 they hope will do well in the road course events due to the Quattro AWD system. The Audi came from the factory with a 3.6 L DOHC V8 with a four-speed automatic transmission. However the team will replace that engine with an all-aluminum 5.3 L L33 Vortec V8 from a GMC truck. The engine will be destroked to 4.8 liters and feature two compound twin-turbo systems from a Power Stroke for a total of four turbochargers. The goal of this system is to build high torque at low RPM and a total of 700-800 horsepower. Power will be sent to the Quattro AWD from a built Audi RS2 six-speed transmission built by Advanced Automotion in Corpus Christi, Texas.
Source: Deboss Garage and Project Page
if the goal is to produce low end torque why they will destroke the already small L33?
Good question. Generally destroking by itself removes low-end torque. They are using the 4.8 L to help with the level of boost they will be running. Deboss answered a similar question with this “The 4.8 handles the boost the best. It has longer dwell and less mass.”
It’s a really dumb idea. A) They are talking about mounting the turbos where the back seat was. This is going to exacerbate the already LAG prone compound turbos. B) Did I mention that compound turbo setups are prone to lag? It’s turbo lag times 2 because you have….wait for it…TWO fucking turbo to spool. C) There is NO WAY they are going to run the boost levels necessary for a compound set up. There is a reason you don’t see gas engine race/drag teams running compound setups. Too much lag, too much pressure, too much complication, cost, weight, and space.
With that said. For shits and giggles it’s cool to see.
mate, look up compound turbo sytems. 2 different size turbos, small one spooling quick and force feeding the big one to spool faster, mean minimal lag and the widest possible power range.
To clarify point C) There is no way they are going run the boost levels that would necessitate using a compound set up. Those diesels are using 50-100+psi. Where 20psi will be pushing it with this engine.
Hate to say it but you’re on to something there. Really it will be a learning situation for him.
Remember he said he was focused on the road race events. You really need great torque in the 2,800 rpm to pull yourself out the corners. So maybe when he says low-end he means mid-range. He probably doesn’t care about lag either because the road race should keep the rpm above a certain level. But your right, we will have to wait and see. There are so many variables that were not mentioned that could influence the system.