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Old 02-23-2012, 05:01 PM   #1
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Default Long-rod BP build underway



Long connecting rod 1.9-ish-liter built VVT BP is being done on Edmunds' green hoopty '97 whine and cheese edition. It'll be a little while before all the bits are in place but it's coming together...

http://blogs.insideline.com/roadtest...d-nerdery.html
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Old 02-23-2012, 05:24 PM   #2
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You appear to have the best job evar.

Keeping the Rotrex?
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Old 02-23-2012, 05:54 PM   #3
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compression ratio?
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Old 02-23-2012, 06:03 PM   #4
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Quote:
Getting the longest rod to stroke ratio is a design mantra
well, it certainly is in my mind. :-)





seriously, though, very cool read. love ---- like this, as it feeds my inner nerd with the stuff that i love understanding but will likely never implement.
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Old 02-23-2012, 06:17 PM   #5
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in for cool new stuff
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Old 02-23-2012, 07:53 PM   #6
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OO ooo OOOOHHHH. I. LIKE.
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Old 02-23-2012, 08:01 PM   #7
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Tasty.


One day. One day I will have a bit of time and money to mildly build a short block.
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Old 02-24-2012, 08:17 PM   #8
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EO2K- am ginning up a turbah
y8s- 9:1
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Old 02-24-2012, 08:51 PM   #9
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I didn't think pornographic pics were allowed...
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Old 02-24-2012, 10:45 PM   #10
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Nice job Jason. Ben trying to research this myself. Talked to J&E, they seemed very willing to work with the customer. So, did Mil-spec end up being a custom rod? What kind of pricing did it work out? What bore did you go out to?
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Old 02-24-2012, 11:32 PM   #11
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How do you get to 1.9 from 1.8 without changing the crank and without lowering the compression ratio?
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Old 02-24-2012, 11:34 PM   #12
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EO2K- am ginning up a turbah
y8s- 9:1
inside line wont know what walloped them upside the assbone.

what order of magnitude for such precious internals kit? Most of us are thinking "supertech and those chinese guys can supply rods and pistons for like 700 for all of it"
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Old 02-25-2012, 03:47 AM   #13
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Quote:
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How do you get to 1.9 from 1.8 without changing the crank and without lowering the compression ratio?
Compression ratio is in the piston design. As for displacement, the 1.8 is actually 1839 cc so it only takes a smidgen of overbore to get a number that rounds up to 1.9L. Going 0.5 mm over is 1860, +1 mm is 1883, +1.5 mm is 1906 cc, assuming my math isn't fuzzy right now.
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Old 02-25-2012, 04:04 AM   #14
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http://www.motoiq.com/magazine_artic...th-matter.aspx

What does a rod like that cost? I have a buddy who just popped an engine, it might be cool to get some of these if the price is right.
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Old 02-25-2012, 04:05 AM   #15
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What are Honda rod ratios compares to our BP "slugger"? Is the higher rod ratio of the F20 the reason the S2k feels a bit sluggish below 5000rpm?
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Old 02-25-2012, 06:30 AM   #16
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What are Honda rod ratios compares to our BP "slugger"? Is the higher rod ratio of the F20 the reason the S2k feels a bit sluggish below 5000rpm?
According to Google...

BP: 1.56:1
S2000: 1.82:1
Chevy 350: 1.64:1
Ford 4.6L: 1.67:1
Nissan SR20: 1.58:1
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Old 02-25-2012, 11:17 AM   #17
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What are Honda rod ratios compares to our BP "slugger"? Is the higher rod ratio of the F20 the reason the S2k feels a bit sluggish below 5000rpm?
The F20C is actually pretty strong below 5000. it is just that when Vtec kicks in (yo) its bipolar welterweight cage fighter side makes the other side feel like a libertarian vegan.
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Old 02-25-2012, 11:34 AM   #18
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Quote:
Originally Posted by Bryce View Post
According to Google...

BP: 1.56:1
S2000: 1.82:1
Chevy 350: 1.64:1
Ford 4.6L: 1.67:1
Nissan SR20: 1.58:1
Thanks. It again appears that we have the worst engine on Earth. Is there an engine from the same era that does worse in than the BP in terms of vibration, rod ratio, head flow, fuel economy, and output?
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Old 02-25-2012, 12:23 PM   #19
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Originally Posted by hustler View Post
Thanks. It again appears that we have the worst engine on Earth. Is there an engine from the same era that does worse in than the BP in terms of vibration, rod ratio, head flow, fuel economy, and output?
BUT, it does seem to withstand a lot of abuse.

Forgive my ignorance, but are we talking about "stroking" the BP? If so, then why not see if there is another crank that will work in this engine?

In the mopar world for instance, you can drop a 440 crank into a 383 and net a 400CI engine. With a new crank and rods you can get 500+ ci from a 440 (this takes grinding inside the block though) Custom cranks are probably expensive, but if Emelio is approaching 200HP on an NA, then I assume "there is no replacement for displacement" holds true.
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Old 02-25-2012, 12:37 PM   #20
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Forgive my ignorance, but are we talking about "stroking" the BP?
No, same crank, longer rod, similar piston with a higher wrist pin. Read the MotoIQ link I posted.
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