Engine of the Week is presented by
There are a number of things that you don’t want to have happen when you go racing. At the top of that list is a crash. However, if you’ve been around racing long enough, you know all too well that it’s only a matter of time before a crash could happen to you.
Sergio ‘Flaco’ Gonzalez, owner of Flaco’s Performance & Tuning in Pasadena, TX, took out his S-10 Chevy truck to race for the first time in No Prep, only to hit the wall in a crash, forcing the truck to undergo a rebuild.
“Our first race didn’t go so well,” Gonzalez admits. “We rebuilt the truck for radial racing and I’ve been doing that ever since.”
Sergio, who’s better known by his nickname Flaco, has been around cars and the racing industry for most his life, first influenced by his father who always raced cars.
“I’ve been around the race track since I was about eight years old,” Gonzalez says. “My dad always had a race car, so I was always around race cars and race tracks and stuff like that. I’ve been in the industry for about 30 years now. I just kept on working on cars and here I am today.”
As mentioned, Flaco owns a shop called Flaco’s Performance & Tuning. The one-man shop is located in Pasadena, TX and is focused on fabrication, tuning and wiring.
“Essentially, I get race cars set up, running and ready to go test,” Gonzalez says. “My main focus is on LS stuff. I’ve been working on LS since 2002. I started the shop around 2005. While LS is the main focus, I will also work on small block Chevrolets and Fords too, as long as it’s race car associated.”
While Flaco’s Performance & Tuning might not do engine work, Gonzalez has several friends who are very capable engine builders, and he does plenty of business with Naiser Racing Engines (NRC) up the road in Houston.
Flaco currently has two S-10 Chevy trucks that he races with – one name Toxic and one named Mona Lisa. In Mona Lisa, Flaco was the first to run a 3-second pass on a 275 tire with an official time of 3.90.
Toxic was the S-10 mentioned earlier that suffered a crash racing No Prep. That truck today is set up with a single turbo, 450 cid LS engine and now runs in Limited Drag Radial (LDR). Behind the wheel of Toxic, Flaco has gone as fast as 4.10 at 182 mph.
“We have run Toxic a lot more and have won a lot more than Mona Lisa,” he says. “We have a lot more data on Toxic. It’s a 450 cid LS engine with a single turbo from Forced Induction. It’s their GT55 107mm. It’s got a center-counterweighted crank, a Dart block, aluminum rods, and Wiseco pistons. The cylinder heads are Mast LS7s. Those are inline heads. The engine features a cast block, cast heads, a CID intake – it’s a pretty straightforward deal.”
When Flaco first got this engine done, a friend of his did the work. When it was time for an engine refresh, Flaco took the LS to NRC, who also did some head work on the engine.
“The combination was well thought out in terms of the camshaft and the cylinder heads,” he says. “NRC did do some work on the cylinder heads so they performed better in conjunction with what we’re doing, and the block can handle plenty of power. In the valvetrain, we decided to run Inconel exhaust valves and titanium intake valves. The camshaft is a solid roller cam from Lil John’s Motorsports.”
Running on alcohol and 45-lbs. of boost, Flaco says this 450 cid LS engine cranks out an impressive 2,600-2,700 horsepower. “It’s somewhere in there in that range.”
Engine of the Week is sponsored by PennGrade Motor Oil, Elring – Das Original and Scat Crankshafts. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor, Greg Jones at [email protected]