Nice! Especially since it is a V12
V12 actually worked in my favor.
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So, I would like to see some OHV entries on this. Given that there is no [simple] way to account for the efficiency/power ratio gap between OHC and OHV engines (without penalizing for engine size by factoring cost), they need to be rated as a separate category. Here is mine:
Engine: LS283
Block: OHV V8 Crossplane
Scoring Stats
Performance: 224.5
Efficiency: 25.49%
Reliability: 77.5
Displacement: 4.6L (283ci)
I know somebody else can do an OHV engine…
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here cobaltgirl my take on RPG’s old cast iron small block
scoring stats:
Performance: 211.7
Efficiency: 29.88%
Reliability: 74.2
Displacement: 333ci/ 5.4L
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Engine: 302TT
Block: OHV V8 Crossplane
Scoring Stats
Performance: 258.7
Efficiency: 25.19%
Reliability: 75.2
Displacement: 4.9L (302ci)
Score: 57.39
@Darkshine5 - The 283 I already showed was cast iron block with aluminium heads, and naturally aspirated. This 302 is Aluminium block and heads, but has twin turbo like yours. Your 5.4L scores 54.58. My previous NA 283 scores 54.75. The 302TT scores 57.39. On a side note, you’re only running Regular Unleaded (91 RON), and it is a 2010 build year, so you could probably improve your score quite substantially over mine.
EDIT: I also just noticed, yours is OHV and not MOHV. This makes an enormous difference as well. Considering these points, very nicely done engine!
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DSD can really tune an engine for efficency 
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Ok so two engines to start with (I can do better but I have too many builds atm to spend more than 30 mins on this)
Engine: 287ci CSBF
Block: MOHV v8 Crossplane
Scoring stats:
Performance: 211
Efficiency: 29.44%
Reliability: 76.8
Displacement: 283ci 4.712L
Score: ?
Engine: 283ci TT
Block: MOHV v8 crossplane
Scoring Stats
Performance: 190.6
Efficiency: 33.89%
Reliability: 76.9
Displacement: 283ci 4.712L
Score: ? can someone just explain what the ^ symble means in the equation? I am guessing its multiple by?
And I may as well put my concept car engine down.
Engine: CCE1
Block: MOHV I6
Scoring Stats
Performance: 304.8
Efficiency: 31.58%
Reliability: 75.7
Displacement: 497ci 8.143L
The little carrot ^ is an exponent.
2^3 = 8
4^3 = 64
And so on
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Here is a highly oversquare 3-liter turbo straight-six I just built. It’s the best effort I’ve made yet:
Displacement: 2999 cc
Performance Index: 214.7
Efficiency: 37.57%
Reliability: 73.2
Overall Score: 141.05
I went for a short stroke and large bore to ensure that the engine could reach peak power with some revs to spare without any loss of reliability. Even then, I needed a very mild cam profile, a fairly high compression ratio, a small amount of boost pressure, and aggressive ignition timing, but I could not take any of these measures too far for fear of compromising any stats that made up the final score.
now do it with OHV and no VVL. Thats not a bad score
OK, so you want me to design an OHV engine without VVL. However, they can be fitted with VVT and direct injection. And does MOHV count? I’m assuming it does.
For the record, here’s a 5.7-liter MOHV V8 with DI and VVT but not VVL (which isn’t possible with overhead-valve setups anyway):
According to the formula in the OP it gets a score of 62.494, with a 9.8:1 compression ratio and a cam profile of 36. How can I improve this, even though the AFR is 15.0:1 and the ignition timing is as aggressive as it can possibly be?
Thats pretty well done. You may find there’s another 1% in the camshaft to compression ratio and what kind of timing are you using? My Goldilocks numbers are usually camshaft profile 36-42 compression for DI around 10:1 timing usually between 52-68 and choke the exhaust just a little and use baffled mufflers I have found VVT to not really do sweat FA unless it is matched with a VVL setup.
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Wat? Is it possible to get score of 162,9 with this engine? Here are my calculations:244,6*(0.3289^1,5)*(69,7^0,5)/2,364 ?
Use cast iron
Just try avoid double-posting as much as possible - you should edit your most recent post instead. For the record, I did not use cast iron for the block or heads since I would have ended up with a heavier engine. A score of >62 for a high-capacity, normally aspirated MOHV V8 is quite high for engines of this type, though.
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I think you used the wrong number for the efficiency - yours is 23.39% (or 0.2339). I calculated your score as 97.71 - still pretty good!
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Last thread is from 2016 which means its already dead as hell.
Either try finding a recent thread or make a new one instead tbh.
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JLS 1.6 ECO (Naturally Aspirated)
1599cc
Performance index: 92.4
Efficiency: 37.23
Reliability: 75.8
Score (if im right): 122.1
Wow…this challenge was held six years ago, in the Kee era, I guess comparing the numbers is kind of an apple and orange affair. 
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