Blown 416: My Journey Building an LSA Engine w/ Mamo Motorsports

It all started with a phone call. A call to the Air Flow legend himself, Tony Mamo, whose career I have followed for quite some time (stemming back to all his accomplishments when he was working for AFR). What began simply as a Mamo Motorsports optimized top end (heads, cam, valvetrain, and a ported blower) transformed into Tony and I embarking on an endeavor to find precisely how much we could extract from the stock 1.9 liter LSA blower and having him design and build a complete 416 CID street friendly engine optimized for boost. We were both curious how much power we could squeeze out of that tiny rotor pack in an LSA block based 4” stroker motor. I’ll answer that question in just a bit. But before we jump to that, I want to share my motivations for crafting this post.

This post sets out to achieve two goals—the first is to document, share & solicit feedback from my build with my fellow enthusiasts. Secondarily to share a bit about my experience building this engine with Tony. To achieve both of those goals, I’m going to share a ton of nerdy details. If you only want to see the numbers, scroll down until you see a cool graph, but I encourage you to check out the journey and share your thoughts and feedback. The fun part is the journey. The numbers are just the icing on the cake.

Basic Rundown

• Brand New LSA Block (Square Decked, Torque Plate Honed to 4.070” & Line Honed)
• Mamo LSA Blower Port Program (105mm Snout, Body & Exits Port Matched To Heads)
• 2.55” & 9.55” Pulley Ratio
• 4” Callies Compstar 8 CCW Crank & Rods (Further Balanced Beyond Callies Internal Balance Program)
• -25 cc Wiesco Pistons (9.75:1 static, Custom Cometic Gasket For Target Quench)
• Custom Grind Comp Cam (235/251, 0.672-inch lift based on a 1.8 ratio rocker & 119+4 LSA)
• Mamo Motorsports 12-degree 26X LS3 Heads
  • AFR Castings
  • 100% CNC with Tony’s optional CNC+ upgrade (comes with additional hand finishing)
  • Custom Ferrea hollow stem 2.170” intake/Solid Stem 1.600” exhaust, both under 100 grams
  • Proprietary Newen Perfectly Concentric CNC Valve Seat Job
  • SF-600 Flow @ 28” w/ 4.065 Bore Fixture
  • 345/244 at 0.500-inch
  • 372/259 at 0.600-inch
  • 382/265 at 0.650-inch
  • 387/268 at 0.700-inch
• Yella Terra Ultralite 1.8 Ratio Rockers w/ Mamo Exclusive 10mm PRO Bolt Upgrade
• Manley NexTek Springs w/ Matching Titanium Retainers & Locators (185-190 seat, 440 open)
• Johnson 2126 ST Axle Oiling Lifters
• Manton Series 4 (3/8” x 0.095” wall) pushrods
• Katech Oil Squirters (Far From Bolt-On!!)
• Mamo Ported LSA Oil Pump
• ID1300 Injectors
• Cloyes Z-Series single roller chain / NGK Copper BR7EF .030 Gap
• American Racing Solutions Tensioner + DMS 110+76mm Idlers & +5mm Relocation Bracket

So, Tony has been building my dream engine over the past few years. His passion for this stuff must be experienced to appreciate it. Watching this engine come to life and forming a friendship at the same time has been one hell of a time. On a routine basis, Tony and I would discuss options, and I would receive pictures like these (he sent me over 130 pictures from the beginning of this project to the end). Looking back on them, they tell the tale of how you make one of the baddest stock block/blower combos out there.



















One debacle that needs extra attention is those Katech Oil Squirters above. You are seeing the final product there. Man, was it a journey in itself!
Going with the 4” Crank, we knew the stock squirters just wouldn’t fit. We assumed the Katech units would “just work” given the price point and reputation of the brand. Instead, Katech claims, “May require some piston skirt clearancing depending on piston design.” We aren’t sure what it is about these Wiseco pistons that are different than any other piston they might have successfully used in R&D. Each piston needed rather significant relieving. Huge time suck. This just adds insult to injury on an $800 set of squirters.



The lack of fitting a standard piston “might” could be expected but really shouldn’t be at the price point of these little deals. However, it just doesn’t stop here.

The suckers didn’t clear the cam, either! So the body of each squirter had to be relieved as well. Lots of time-consuming in and out trial fitment (similar to the piston fitment and clearancing) because we wanted/needed enough clearance but couldn’t get aggressive because Tony was afraid to break into the actual oil passage in the squirter, which would have compromised its function. Suffice it to say he wasn’t too happy with the design of the piston squirters!





The amount of time and attention to detail it takes to get this, and more generally, everything right, should be abundantly clear. The squirter incident is a seemingly small example of the types of things that can creep up and bite you if you don’t catch them during mock-up (or final assembly). Building a high-power, reliable motor is not simple or fast. There were other obstacles as well that slowed us down. The cam didn’t go past the 3rd journal. Pushrod clearance that was supposed to have been done by AFR’s CNC machine wasn’t enough. Tony had to inform them that 3/8 rods do NOT clear with a 1.8 rocker, and he had to remove the heads to clearance them further by hand. The blower didn’t fit with the head milling and thinner gaskets. Also, we had to figure out how to modify the belt routing to work on the dyno since we had to run the stock mechanical water pump due to the supercharger pulley system. That obviously took a creative solution. These were just some that I remember, a lot of unexpected obstacles. It definitely kept Tony busy (and a bit frustrated), but he took care of what needed to be done and moved forward. Towards the end, he would call when the next hiccup came up, and we would laugh about it. He said no other motor fought him to go together as much as mine did, but he said it feels great and always left me feeling good about things regardless. Yet, through the challenges, while many, we ultimately triumph.

All of this culminates in finally waking up to these stunning two pictures. Man, was I pumped when I saw these!




So how did this day that seemed to take so long arrive so fast!? After Tony finally locked on to a dyno date, I eagerly booked my flight to Mamo Motorsports in Valencia, California! The evening before I left Georgia, Tony drove the engine to the legendary Westech Performance Group so they could get the engine on the dyno the day before the actual test. This allowed them to get it fired up and run a break-in procedure programmed into the Superflow dyno before our arrival the next day. When I landed in LA, I received word that the oil pressure was great and no odd sounds were emitted from the motor. The report included zero issues during the fire-up and break-in. Our first big hurdle has already been cleared!



After arriving in LA and a short ride north to Valencia, I meet Tony at his shop for dinner. We take his super clean modded V to a Mexican joint. On the way back from the restaurant (while still in Mexico), a C7Z06 driving aggressively blows by us. I see a devilish grin on Tony’s face, and the powers that be put us next to one another at the next traffic light! He kills us out of the hole as Tony is peddling the “V” trying to keep it straight, and we go by him pretty well in 3rd gear when the car is finally settled down and pulling hard. Man, I'm already having a blast, and the best part (dyno day) is still yet to come



When we return, Mamo quickly puts me to work flowing cylinder heads. I’m a natural! Tony actually took the time to explain and demonstrate the nuances of flowing a head and the process involved, which was fascinating. He had to flow test a new BBC program he was working on, and I got to experience that. The air blast from the exhaust port tube, which simulates a header, was incredible.



I’m only slightly bummed, 😊, as I have to wait to see the engine for the first time tomorrow, Dyno Day!



The day is here, and we are here. It’s honestly crazy to meet Tony and Steve Brule & spend time in the Westech Dyno Cell all in the same 24-hour period. This is stuff dreams are made of! Lots of history has been made in that building. Trust me, you can feel it.



After making sure I’m not dreaming & before warming the motor up, we pour some pump Ethanol (More on the % later) into the fuel cell and cut open the oil filter looking for that clean bill of health so we can proceed with the testing.




Everything is looking great. The filter element and the oil in the canister look pristine after the break in cycle. We are cautiously optimistic about the power & general teething issues ahead.



With the green light from the oil filter behind us, Steve & Westech’s EFI tuner (Ish) start to dial the fueling in with some step test pulls. Steve programs in a set RPM, and the dyno holds the engine at the set RPM as Steve opens the throttle and puts a load on it, slowly rolling all the way to WOT only if the AFR looks close. The fuel map is intentionally started extremely fat. As we sit at our first step (3k RPM), Ish dials the AFR in. We repeat the process all the way to 5k RPM. Fueling is looking good enough to start the sweep pulls. We start with low, narrow (3-4.5k), and fast (600 rpm/second) sweeps and progress to high, wide (4.7 – 6.5k), and slow (300 rpm/second) sweeps as the fueling and timing get dialed in. This process is a mixture of extreme anticipation, excitement & fear I have never felt before. You can feel the cylinder pressure across the plexiglass window. The room shakes violently, and the lights in the cell seem to flicker. We are already seeing over 800 ft/lbs of torque with a really soft tune-up!!

As we close in on the final runs, we are thrilled with the results, but there is still one question in Tony’s mind. This a question that very few people would probably even think to ask. With that fairly ginormous 109 mm TB, would a radiused inlet on the front of it help our cause? He is convinced it will, as he spent about 8 hours fabricating the thing weeks before the dyno test (you would never know it's actually made out of wood!). So we installed his custom radius plate TB entry and pulled the engine one last time.




Tony guessed the smoother entrance would be worth at least ten, and it didn’t disappoint! We pick up a little more than a half-pound boost and 14 ponies. I swear I think about all the hours Tony has spent parked in front of a flow bench that he actually sees the airflow at this point!

Listen to this engine sing, especially when Steve rolls into the throttle. The experience from the back room of the dyno cell was insane, let me tell you. Crank up the speaker's volume.






We finished @ 963/888. Looking at the data, it's obvious the torque peak happens at a lower RPM, and unfortunately, due to time constraints, we only really optimized the upper sweeps, which we started at 4700. Had we started lower, the duration of the pull would have been longer than optimal, and we were already seeing 140-degree IAT’s at the end of the pull that started at 4700 (which was 9 – 10 seconds in duration). We were slightly bummed out that the largest LS header there only had 1 7/8" primary pipes and a 3” collector. A 2” header on this beast is a must, and Tony (and Steve) both agreed it would have been worth a significant gain at this power level (I will be running a 2” header in my car). We also felt there was more to be found tweaking the fuel curve (the last change we made there moved it 2-tenths of a ratio and picked us up 13 HP!), but once again, the time we had to test was compressed due to them only having one dyno. Cooler IATs, a little more tuning time, and a more appropriate header would have landed very close to, if not over 1000 HP and 900 Ft/lbs of torque. Our main goal in dyno testing was to ensure the health of the motor, of course, but as the five of us all pitched in to remove the engine from the dyno chassis, it truly felt like an immense victory. The power numbers she made blew away our expectations.

Also, Before we left, Westech ran an emergent quantum discombobulation test 😊 on our pump station E85 fuel as we were curious about the exact Ethanol content. It turns out we made all that power on E73. (I told you I would come back to this)




With all the critical questions answered, we returned to Valencia, just like we came, with a quick pitstop at “CowBoy” restaurant for a celebratory lunch. Let's just say the engine in the back of the Dually got a lot of curious stares from people coming in and leaving the place!



Getting The Beast Home

So Tony actually has a panel saw in his shop and builds these custom engine crates by hand & loads the truck himself using his “favorite yellow tool in the shop” 😊 (Btw, the engine, as you see below, is only 443 lbs including the weight of the steel engine cradle!!). Even the craftsmanship in the engine crate is another testimony of Tony’s attention to detail. This guy is definitely OCD, but he puts it to good use!









The engine is due for delivery this coming week. My car is a Slick Top, Recaro, Radiant Silver 6MT Sedan. The guys at Westech were sure to tell me numerous times to forget about traction (and something about adding them as a beneficiary to my life insurance policy??) and, of course, to be sure and share a video when the car is running, which I will 100% oblige.

So for those still reading, I’m circling back on my purpose for this post, which is mostly twofold.

#1. I’m eager to hear feedback on what you think about the build, both positive and constructive. I’ll do my best to answer any questions I can, and I know Tony will be lurking for anything out of my range. The post is my small way of giving back, as I have many questions already on the top of my mind as I put the car back together. I plan to share a ton more. Please let me know if anyone would like to see anything specific. I have many additional pictures/videos I couldn’t fit into this post.

#2. It also goes without saying this post should also be read as a ringing endorsement of Tony’s work and his way over-the-top attention to detail and customer service. It’s not just the numbers and flawless execution on the dyno. You all already know the quality of his work. That has been established for decades now in the larger LS community. My goal here was to share a bit about deeper, longer-term builds with him and how personal a journey it was working with him in this regard. There really isn’t a price you can put on this type of customer relationship, and the meticulous work and attention to detail that’s especially critical in larger, more expensive projects like this. The experience is absolutely not the same as calling up a volume engine place, which I have obviously done before. A couple of other full-build threads floating around on the net that speak of something very similar, and I highly recommend it. If anyone is thinking about getting something done with Tony, read this as the huge endorsement it is meant to be, and if you have questions, I encourage you to reach out to him. I know you will be glad you did!