McCully Racing Motors
#1
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Join Date: Jan 2014
Location: Green Cove Springs, Florida
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McCully Racing Motors
in the course of looking around learning and researching for a future motor build, I came upon this:
McCully Racing Motors- Don't want a V8? How about a 2.0?
It is a company that sleeves 1.8 motors to yield a displacement of 1.952 liters. Their reasoning is that gaining displacement by bore was better, in the case of the Miata motor, than stroking it because it would keep the rev characteristics the same. They sell everything from a bare block to short block with forged pistons and forged rods ( quality commensurate with price ). I would like to have a built engine even though my power goals are modest. I'd just like to know that my engine would be pretty much bulletproof for my needs ( street driving and occasional auto x) at about 250 -275 whp. The Miata is one of my hobbies in my retirement and it doesn't need to be a budget project.
Even though I have assembled,engines in my younger days, I would need a machine shop in any event, so buying a pre-built block isn't out of the question.
Does anyone have any any experience with these folks? Opinions on the motor? My concern would be no, or minimal, space between the sleeves might reduce ability to cool. But then again, I really have no idea if that would be the case. The photos show the block, after being sleeved, and the sleeves would literally have to be nearly touching each other.
Thoughts?
Paul
McCully Racing Motors- Don't want a V8? How about a 2.0?
It is a company that sleeves 1.8 motors to yield a displacement of 1.952 liters. Their reasoning is that gaining displacement by bore was better, in the case of the Miata motor, than stroking it because it would keep the rev characteristics the same. They sell everything from a bare block to short block with forged pistons and forged rods ( quality commensurate with price ). I would like to have a built engine even though my power goals are modest. I'd just like to know that my engine would be pretty much bulletproof for my needs ( street driving and occasional auto x) at about 250 -275 whp. The Miata is one of my hobbies in my retirement and it doesn't need to be a budget project.
Even though I have assembled,engines in my younger days, I would need a machine shop in any event, so buying a pre-built block isn't out of the question.
Does anyone have any any experience with these folks? Opinions on the motor? My concern would be no, or minimal, space between the sleeves might reduce ability to cool. But then again, I really have no idea if that would be the case. The photos show the block, after being sleeved, and the sleeves would literally have to be nearly touching each other.
Thoughts?
Paul
#4
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MCM has been around for a while. For your power goals, sleeves and 85.5mm pistons are way, way overkill. Stock displacement is 1839cc, 84mm overbore is 1884cc (2.5%), their sleeved "2 liter" is 1951cc (6%). IOW, you can get about half the increase for far less than half the cost. Stroker setups like FM's 84.5x89mm produces a ~1996cc powerplant, but the extreme cost makes them very difficult to justify for most customers.
More to the point, the money is simply better spent elsewhere at your proposed power levels. I personally suggest 83.5mm to most people which makes the blocks serviceable in the event of a future incident or future rebuild, since the ~1% displacement gain is going to be difficult to measure, let alone feel or notice in the real world.
Spend the extra money on a better turbo setup, or a better intercooler, or a better exhaust, or better injectors, or a more modern ECU, or a new intake manifold, or more tuning time. All of those will make a bigger difference in how the car drives than the extra displacement.
More to the point, the money is simply better spent elsewhere at your proposed power levels. I personally suggest 83.5mm to most people which makes the blocks serviceable in the event of a future incident or future rebuild, since the ~1% displacement gain is going to be difficult to measure, let alone feel or notice in the real world.
Spend the extra money on a better turbo setup, or a better intercooler, or a better exhaust, or better injectors, or a more modern ECU, or a new intake manifold, or more tuning time. All of those will make a bigger difference in how the car drives than the extra displacement.
#5
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Join Date: Jan 2014
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Thanks for the responses. Going with a different motor ( K -series) is pretty much out as I already have a nice turbo setup, ECU, cooling system, transmission, etc. If I were just wading into this, perhaps I'd consider that route.
Savington, good advice. I'm pretty happy with the power levels of my FM2 but just want to go bullet proof. My current motor has about 105k on it and seems healthy. So, I have time to plan my build. I would like to acquire the block and build while using the car with the current motor. Overbuilt for the power I'll be asking is kind of what I'm looking for. If I ever get the bug to go to a bigger turbo, more boost. I'll have the option.
I'm sort of keeping my eyes open for a decent engine candidate for a build and would like to track down a machine shop that can do the work and give me input on bearing sizes, etc. I don't want to assume that I know something and screw it up. I know that:
I want to go forged pistons and rods. 9:1 Compression ratio sound right? Good bearing and main and rod bolts per Emilio's sticky. Probably stock VVT head valve job, seals new stock or slightly better springs. Not looking for crazy high RPM.
ARP head bolts, coolant reroute with appropriate head gasket, upgraded ( inconel?) exhaust manifold bolts. Boundary oil pump?
I live in Northeast FL. There are a couple of Spec Miata shops in the Daytona vicinity that would probably be a decent choice for the matching shop work.
Sound about right?
Paul
Savington, good advice. I'm pretty happy with the power levels of my FM2 but just want to go bullet proof. My current motor has about 105k on it and seems healthy. So, I have time to plan my build. I would like to acquire the block and build while using the car with the current motor. Overbuilt for the power I'll be asking is kind of what I'm looking for. If I ever get the bug to go to a bigger turbo, more boost. I'll have the option.
I'm sort of keeping my eyes open for a decent engine candidate for a build and would like to track down a machine shop that can do the work and give me input on bearing sizes, etc. I don't want to assume that I know something and screw it up. I know that:
I want to go forged pistons and rods. 9:1 Compression ratio sound right? Good bearing and main and rod bolts per Emilio's sticky. Probably stock VVT head valve job, seals new stock or slightly better springs. Not looking for crazy high RPM.
ARP head bolts, coolant reroute with appropriate head gasket, upgraded ( inconel?) exhaust manifold bolts. Boundary oil pump?
I live in Northeast FL. There are a couple of Spec Miata shops in the Daytona vicinity that would probably be a decent choice for the matching shop work.
Sound about right?
Paul
#10
Former Vendor
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Empirically, they hold up well as far as I know. I have no personal experience but I've heard good stories from others. If I were building a max-effort motor to withstand an EFR7163, they would be on the build sheet. For a 250 or 300 or even 450whp non-competition motor, no way.
#13
Part of the thrill for me is seeing how far I can go with what makes a Miata a Miata. The motor they came with is an important part of that journey.
No disrespect to those who enjoy swapping motors. You guys have made some impressive cars. If I wanted to go really fast, I would go that route, or go back to my Camaro and Mustang days where I went pretty fast.
No disrespect to those who enjoy swapping motors. You guys have made some impressive cars. If I wanted to go really fast, I would go that route, or go back to my Camaro and Mustang days where I went pretty fast.
#14
I sleeved a block for personal use. (haven't built the motor yet) the one issue with a highly boosted >350hp sleeved build would be worrying about the block cracking around the head bolt threads. It could be ok but its not worth the extra few percent imo and would rather see 83.5-84mm pistons go in as well.. i might even go as far as stroking it.
#16
Yeah, there's less material around each cylinder, due to the hole of the neighboring cylinder being bigger. That's why there are only NA type pistons available in the 85.5 size. I'm up to 84.5 (second rebuild on this block) and will probably retire the block if it gets up to 85mm and needs more work. But that could be years.
On a miata, spending over 3k to increase displacement by a tiny amount is a pretty poor investment. All of the gains from this undertaking can be replicated by running a extra pound or two of boost.
On a miata, spending over 3k to increase displacement by a tiny amount is a pretty poor investment. All of the gains from this undertaking can be replicated by running a extra pound or two of boost.
#18
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Adding displacement isn't necessarily the most cost-effective way to increase the volume of air entering and leaving our engines. If you've done everything else or money is no object and you have to stay with the BP, then sure.