My first N/A build
#1
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Join Date: Nov 2013
Location: Sardinia, Italy
Posts: 396
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My first N/A build
After my experience with my 420hp BP (6758, TSE, built VVT, yada yada yada) I decided to sell everything and start with a completely different project: build a N/A, high hp engine with a budget of 4000€, primarly because I've got another BIG project in mind, and I didn't wanna spend too much on a temporary engine
First I bought a fresh chassis: a Miracle NB1 with BP4W, 6 speed and a 3.636 r&p
After that, I started to build the engine:
11:1 CNC modified pistons, near 300 degrees cams, shim under bucket, custom valve springs (exhaust and intake are different), ITB's from a 2008 CBR1000rr, custom cnc velocity stacks, 4.5kg flywheel, OBX NA 1800 headers, custom 2.5" midpipe and a cobalt exhaust (straight pipe 2.5")
Everything else is stock: connecting rods, head is untouched, stock valves and retainers, even the rings are the old one, cleaned and reinstalled as they was. Only thing is that the bottom end was from a VVt engine (reinforced mains, high flow oil pump) but the head is a BP4W one.
Result: peak power at 8000rpm, had to swap the rx8 yellow because stock went over 100% from 6000rpm
It's a really nice engine, really good sound
First I bought a fresh chassis: a Miracle NB1 with BP4W, 6 speed and a 3.636 r&p
After that, I started to build the engine:
11:1 CNC modified pistons, near 300 degrees cams, shim under bucket, custom valve springs (exhaust and intake are different), ITB's from a 2008 CBR1000rr, custom cnc velocity stacks, 4.5kg flywheel, OBX NA 1800 headers, custom 2.5" midpipe and a cobalt exhaust (straight pipe 2.5")
Everything else is stock: connecting rods, head is untouched, stock valves and retainers, even the rings are the old one, cleaned and reinstalled as they was. Only thing is that the bottom end was from a VVt engine (reinforced mains, high flow oil pump) but the head is a BP4W one.
Result: peak power at 8000rpm, had to swap the rx8 yellow because stock went over 100% from 6000rpm
It's a really nice engine, really good sound
#4
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Join Date: Nov 2013
Location: Sardinia, Italy
Posts: 396
Total Cats: 56
For those curious about the power curve, I've done some VD logs:
blue is a stock VVT with cold air intake, green is a stock BP4W with itb's and obx exhaust, red is the 300 degree cam 11:1 engine with 95 octane (you can compare to 91 usa octane)
and (sadly sound isn't great on my phone) that's a video:
blue is a stock VVT with cold air intake, green is a stock BP4W with itb's and obx exhaust, red is the 300 degree cam 11:1 engine with 95 octane (you can compare to 91 usa octane)
and (sadly sound isn't great on my phone) that's a video:
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