Limited Late Model Motor - Build Your Own Race Engine, Part Four

At last, we're finally ready... 

   

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At last, we're finally ready for the dyno.

Finally, there's light at the end of the tunnel. In this, the fourth installment of Circle Track's Limited Late Model engine build, we're finishing up the assembly before heading back to KT Engine Development to dyno test our results. This is the fun part of the build, all the pre-fitting and measuring has already been done, and many of the steps on the following pages make the engine look complete. But just because we're doing "simple" things like bolting up the oil pan and valve covers, this is still not the time to get careless. Attention to detail is paramount if you want all your hard work to result in a race engine that not only makes good power but also will be dependable race after race.

Remember, our goal when we started this series, was not just to impress you with a cool engine when everything is finished, but to show you how you can do much of this work yourself. The money you save can go toward purchasing better-quality parts or the tire bill. It doesn't matter as long as it's assisting your racing program.

Along the way, we've tried to provide plenty of tips that will help you should you try to build-or rebuild-your own race engine. We chose a Chevrolet because it is by far the most popular make of engine to be found on tracks across the country, but no matter what brand you race or what class, much of what is found in this series can benefit you. After all, it doesn't matter if you are racing a pure stock or a Super Late Model, good engine-building practices don't vary. Let's get to it.

In the last installment we...        read full caption In the last installment we put the valvetrain together, and if you remember, we had issues with the pushrods rubbing the heads. We fixed this with Isky's adjustable guide plates. But we ran out of space and didn't show you that while we got the pushrods where we thought we wanted them, we totally screwed up the rocker locations. As you can see here, the rockers' roller tips aren't centered on the top of the valve stems. This is an engine failure just waiting to happen.	This can be fixed by grinding...        read full caption This can be fixed by grinding the interlocking tabs on the Isky pushrod guideplates to build in even more adjustability. With the rockers studs loose so that the guideplates can be moved and the rockers sitting on top, everything was adjusted until the pushrods weren't rubbing and the rockers were centered over the valve stems.	Before installing the front...        read full caption Before installing the front seal, apply a thin layer of silicone around the edge of the opening in the timing cover to keep oil from leaking around the outside edge of the seal.
Gasket prep not only helps...        read full caption Gasket prep not only helps prevent leaks, but it also makes the gasket tacky enough that you can stick the gasket wherever you want and it won't move while you get the other component fitted up. But it's a good idea to only apply gasket prep to one side. If you apply it to both sides, it can sometimes make the gasket "squirm" or move slightly when you are tightening down the bolts.	Before bolting up the timing...        read full caption Before bolting up the timing cover, liberally apply assembly lube to the chain while you spin it over at the crank. The chain only gets splash oiling, so no matter how much you prime the oiling system before initial startup, it won't get anything.	One product that can make...        read full caption One product that can make your life a lot easier is an engine-specific bolt kit from ARP. It has all the correct bolts you will need for bolting up all the accessories-everything from the timing cover, to the oil pan, to the distributor bracket-all in one package with everything marked. It eliminates a lot of time wasted rooting around in your bolt bucket or making trips to the hardware store when you realize you don't have the fastener you need.
For this install we're using...        read full caption For this install we're using a Moroso standard-volume oil pump, which comes with an excellent oil pump driveshaft. Don't make the mistake of using a stock-style pump driveshaft. It uses a plastic locking collar, which can break and leave you without any oil pressure. A good aftermarket pump driveshaft like this one uses a steel collar which won't break. Make sure the pump driveshaft stays engaged with the oil pump while you are sliding both into place.	The oil pump is held in place...        read full caption The oil pump is held in place with a single bolt; there is no gasket.	You need to make sure the...        read full caption You need to make sure the oil pump is clean inside and out, so go ahead and remove the four bolts holding the cover in place.