Racing Engines - Crate Or Built?

My guess is that you have already read some articles exploring the issue of using a crate engine versus a built engine to power a typical Late Model Stocker or the like. I know I have and each writer, for the most part, seemed to have some vested financial interest in the situation.

It's understandable that engine builders are unlikely to be big proponents of crate motors. For track owners whose primary interest is filling seats, things could be somewhat different. Full starting grids are what race fans want, and going the crate motor route with the intent of cutting costs should lead to more cars. On the face of it, apart from being diametrically opposed, there does not seem to be many issues here. But, when delved into in more detail, the reality of the situation is far more complex.

Like others who have put forth their thoughts on this subject, I, too, have an axe to grind. I want to see a situation that best fits the needs of the racer and the track owner. I feel my position as a racer who builds (or shows others how to build) race engines but can better afford crate engines makes me reasonably unbiased. With that said, here are my observations from helping No. 10 Andy Mercer and No. 64 Nick Losito, two drivers who competed at Hickory (North Carolina) Motor Speedway last season.

The year started with us running just the No. 64 car, but we ended up joining forces with the No. 10 team when we saw that we could benefit from their chassis knowledge and they could profit from our engine expertise. Both cars ended up highly competitive, but the Mercer car used a built motor while the Losito car used a Chevy crate motor. Let's start the ball rolling with the crate motor.

So, what does the crate engine have going for it? As a value deal, General Motors does a good job of putting a viable race car powerplant into the hands of an otherwise financially challenged racer/team. We bought our Late Model, complete with crate motor power, from a major-league team that was running it as part of a NASCAR driver diversity program. We got the car with track test time and some 20 races on it. While Nick Losito, hot off multiple karting championship wins, got seat time at Hickory, I decided to do a little research on what it takes to fine-tune a crate motor.

Some tracks want sealed engines, while some (e.g., Hickory) allow the engine to be rebuilt. This rebuild allows refinished bores, but you don't get the option of larger pistons. Stock replacement rings and bearings are mandatory. Replacing these parts, fine-tuning clearances, and selecting stock parts (such as valvesprings) is about the extent of what can be done without incurring a rule infraction.

The first person I consulted for crate motor tips was Ken Troutman of KT Engine Development in Concord, North Carolina. According to Ken, the out-of-the-box crate motor typically generates between 400 and 418 hp, with 405 being about the norm. However, within a couple of races, almost regardless of the starting point, the power would usually drop to about 390. Ken's take on this was that the factory honed the blocks without a deck plate, and the best ring seal came in but then went away to a stable, lower level in approximately 100 race miles. After deck-plate honing the minimum out of the block, a re-ringed but otherwise stock crate motor would put out about 410-412 hp and pretty much stay there.

I found this power decay theory of Ken's very interesting. By the time Nick had put in some 1,000 test laps in the No. 64 car at Hickory, we took out the motor to dyno it, freshen it up, then re-dyno it. Ken's prediction was frighteningly accurate (or lucky), as our motor put out exactly 390 hp before it was rebuilt (Fig. 1).

At this point, we tore down the motor and shipped the block to KT Engine Development to receive new cam bearings and be hot-tanked and deck-plate honed. The heads were stripped and cleaned, the valves check-lapped, and new selected stock valvesprings were installed. Before starting Ultra Pro Machining (which services heads for Cup cars), Nick's dad, Don Losito, was the engine builder for Kenny Bernstein's Cup team, and Don rebuilt the engine. When run on the dyno, our engine made right around 412 hp and-bearing in mind no oversize pistons are allowed-we knew how to keep it there all season. Other than meticulous ring and bore prep, long life depended on a top-notch air filter and equally top-notch oil.

About this time, we got a spare crate engine from a team that was graduating from Late Model competition. We put it on the dyno as received and were surprised to see it crank out a hair shy of 430 hp and torque to match. But any excitement at the prospects of using this motor quickly vanished when a teardown revealed it was far from legal. Getting back to a legal situation with this unit required a new block and heads. Using this and our other motor, we found what it took to make an extremely competitive engine approach 420 hp-legally.