Mast Motorsports Dyno – LSX Engine Epic Part 4

Kick the tires and light the fires! Well, maybe not all of that yet, but we can definitely light off the Mast LSX 440 and burn up some fossil fuels on the Mast Motorsports dyno! In the last installment of the Mast Motorsports Engine Epic (part 3), we completed the LSX 440 and were ready to test and tune. Get ready, Turn up your volume, and tell your significant other your busy, because this is where I show you how much fun the guys at Mast Motorsports have. It’s dyno time!

Mast Motorsports dyno tests each and every one of their hand built LSX engines.  Greg’s engine was no exception. In fact, there was a buzz around the shop about this particular build because not very many “Old school” carbs come through.  It’s pretty cool to see everybody in the shop come up to Perry Kiritsy and check up on his progress, place bets on the final power output, and shoot the breeze with us. Greg’s LSX 440 was the first build to have a 950 QFT carb, use the GM carb intake (part # 25534394), and contain a custom ground cam of Perry’s own creation. This engine was different and everybody was curious to see how it performed.  So without further delay, lets get this show on the road.

Once the engines are completed, they are transferred over to the SuperFlow dyno cart, the dyno flywheel and drive plate are bolted on, and the engine is transported to one of the dyno rooms.

Once the engine is in place, Perry Kiritsy and Damon Sampson begin the connection process. EGT sensors, water pump, headers, controls, fuel; everything this engine needs to run.

Now its time for some fun! With Damon at the controls, the LSX 440 went through a series of checks before the engine was even started – like a pre-flight checklist. The MSD box had a custom timing program plugged in and everything was monitored on initial start up. During this warm up period, several starts and stops were were performed to check on the engine. The engine went through a series of small RPM increases and load increases until Damon felt it was ready to test the engine output. In this next video, I have edited the Dyno runs down to the exciting parts. Basically, what you see here is several dyno pulls in a condensed shot. Between each dyno run there was a warm up idle and cool down period and only a couple adjustments of the custom timing in the MSD box. This small block is a screamer, check out the headers on the last run! Max RPM/power was not reached in this video, but still intense!

Anyone like a view from the Captains seat? This next video shows the control panel and one of the initial dyno pulls. The engine was shut down at 6200RPM, and the graph shows some tweaking was necessary in the MSD timing. A straight, climbing line on the graph is what we want. Yes, there is much more power in this engine-so don’t let those numbers fool you.

Big noise! Big RPM! Big Power! Small Block! Here is the final GM intake 6800 RPM run from inside the dyno room.

Results of the GM intake, QFT BDQ-950 carb equiped Mast Motorsports LSX 440: Max Power 708.3 HP at 6800RPM; Max Torque 591.2 ft-lbs at 5500 RPM.  That’s actually pretty amazing considering we did not adjust the carb at all. It was simply pulled out of the box and bolted on. Also, the GM intake is a short rise intake, and like typically seen in other applications, a high rise intake will build more power.

The GM intake was used on the LSX El Camino due to hood clearance issues. While still a potent intake, the guys at Mast Motorsports knew we left some power on the table. They had a Mast Motorsports LS7 carb intake on hand, and of course we had to try it! This intake is a CNC ported intake that is maximized for intake air velocity. The difference in power output using this intake was awesome! We wished we could have used it!

We added approximately 30Hp and 25 Ft-lb of torque just by bolting on their intake and not adjusting anything! If we had the time to tune this set up, we knew we could get even more. To see how this intake can help your engine combination, contact Mast Motorsports directly. They can help you figure out how to maximize your power potential!

Since Nacodoches, Texas is a bit of a drive from St. Louis, Missouri; we needed to get back on the road if we were going to make it back to our respective day jobs on Monday! The engine came out of the Dyno room, off the run stand and into a custom built shipping crate. We loaded it up, said our good byes, and headed north. What an amazing experience!  Mast Motorsports has got to be a fun place to work . The crew was very welcoming and fun – we made some great friends while we were there! The owner, Horace Mast, was great – what an exceptional leader! The products create a reputation for anyone that is associated with them and is why Mast Motorsports is second to none in our book

Keep checking back to see the final chapter of the Mast Motorsports LSX 440 being installed into the LSX El Camino. There is some really cool engineering and cosmetic ideas that all you LS carb guys may want to see.

Thanks for following,


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