All Motor B20 Vtec BROKEN!! Please help
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All Motor B20 Vtec BROKEN!! Please help
Good day to all members. i am new to the honda tech forum and this is my first post, unfortunately its not a happy one.
Il get straight to the point.
I not too long ago built a B20 Vtec in my civic. With just Over 20 000km's
on the engine the motor broke! i am left speachless. The motor was built by
a reputable tuner (JDM Tuning) and all parts were original and new.
Here is the parts i used in the build:
B20 block (honed)
Standard Crank
Eagle Rods
Wiseco Pistons
Acl Race bearings
B16 Vtec head
OEM Valves
ARP Head bolts
B16b cams
BC dual valve springs and retainers
Honda gaskets
Gates Blue Belt
Castrol Magnatec oil.
What happened...While on the highway i was flatout in third gear and
took it to around 8800rpm and when i changed to 4th gear...snap!
upon opening the motor, piston number 3 had broken.
the piston had broken off the rod with the pinnion still in the rod.
how can a forged piston break so easily?
Please help me out guys i have no idea what to do...
any info would be greatly appreciated.
Il get straight to the point.
I not too long ago built a B20 Vtec in my civic. With just Over 20 000km's
on the engine the motor broke! i am left speachless. The motor was built by
a reputable tuner (JDM Tuning) and all parts were original and new.
Here is the parts i used in the build:
B20 block (honed)
Standard Crank
Eagle Rods
Wiseco Pistons
Acl Race bearings
B16 Vtec head
OEM Valves
ARP Head bolts
B16b cams
BC dual valve springs and retainers
Honda gaskets
Gates Blue Belt
Castrol Magnatec oil.
What happened...While on the highway i was flatout in third gear and
took it to around 8800rpm and when i changed to 4th gear...snap!
upon opening the motor, piston number 3 had broken.
the piston had broken off the rod with the pinnion still in the rod.
how can a forged piston break so easily?
Please help me out guys i have no idea what to do...
any info would be greatly appreciated.
Last edited by GreenbeaN069; Nov 16, 2012 at 02:23 AM.
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Re: All Motor B20 Vtec BROKEN!! Please help
Sounds like you dropped a valve (stock, used) while getting an "over-rev" while shifting. What did you set the BC springs installed height to? It makes a difference. Also what is the REAL rpm number @ 8800 on your stock tach? I have seen them off by 1000 @ the top.
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Re: All Motor B20 Vtec BROKEN!! Please help
shyte happens every now again... some more than others..
The valve obviously contacted the piston, you must have lost cam/crank synch on cyl 3 somehow (valve spring could have "bound" or "float")
Check, the valve springs, retainers and cotters.. esp on cyl 3
How old are the valves?
Could have had something enter the intake (but only cyl 3??)
Cyl 3 usually runs the hottest..
Piston looks steam cleaned on intake side..
det, lean, ping ???
Check injector number 3
8800rpm on 240cc injectors.. on a 2lt with ctr cams???
the deformation of the piston was through valve "shrapnel" and excessive heat..
check plugs and cyl head chambers..
I think most likley order of events... Piston pin broke away from piston... eagle rod with pin pounded unattached piston into valve and chamber.. could have been through lack of piston oiling at pin areas (pin lock up - siezed) and excessive friction and heat... the rest followed
The valve obviously contacted the piston, you must have lost cam/crank synch on cyl 3 somehow (valve spring could have "bound" or "float")
Check, the valve springs, retainers and cotters.. esp on cyl 3
How old are the valves?
Could have had something enter the intake (but only cyl 3??)
Cyl 3 usually runs the hottest..
Piston looks steam cleaned on intake side..
det, lean, ping ???
Check injector number 3
8800rpm on 240cc injectors.. on a 2lt with ctr cams???
the deformation of the piston was through valve "shrapnel" and excessive heat..
check plugs and cyl head chambers..
I think most likley order of events... Piston pin broke away from piston... eagle rod with pin pounded unattached piston into valve and chamber.. could have been through lack of piston oiling at pin areas (pin lock up - siezed) and excessive friction and heat... the rest followed
Basically what happened at the begining of the build is i originally had a oem Honda belt on this build with BC0013 instead of ctr cams along with new brian crower valves.With 200 kms on the engine the brand new honda belt snapped resulting in all my new bc valves being bent. The tuner investigated and explained that the new bc valve springs ere too stiff/tight for a oem honda belt to handle. This is why he informed me to get a Gates belt.
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Re: All Motor B20 Vtec BROKEN!! Please help
Im not surprised you didnt ask this on myhonda poser dc2 and rex forum lol..
I assume you have a sealed vc, with no adj cam gears..?
If it was a valvetrain issue that started the destruction.... then
CTR cams and those buddy club or brian crower vspring do not call for the blue belt..
Unless those are the high "rate" brian crower vspring's but even so, the cams dont have the lift, duration and ramp to warrant a blue belt..
"Honda" dont/didnt use bc vsprings nor the blue belt with CTR cams...
Nevertheless... paper... rock... scissors.... in this case "blue belt" > oem valves > wiseco forged pistons.... unless it snapped tooO..
I assume you have a sealed vc, with no adj cam gears..?
If it was a valvetrain issue that started the destruction.... then
CTR cams and those buddy club or brian crower vspring do not call for the blue belt..
Unless those are the high "rate" brian crower vspring's but even so, the cams dont have the lift, duration and ramp to warrant a blue belt..
"Honda" dont/didnt use bc vsprings nor the blue belt with CTR cams...
Nevertheless... paper... rock... scissors.... in this case "blue belt" > oem valves > wiseco forged pistons.... unless it snapped tooO..
The belt hasnt snapped
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Re: All Motor B20 Vtec BROKEN!! Please help
I am not sure about the install height i will have to check with my tuner.
Also i would need to doule check whete limiter was set on the management.
Would this build not handle 9000rpm?
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From: Quebec, QC, Canada
Re: All Motor B20 Vtec BROKEN!! Please help
have you ever dynoed this engine?
b20vtec with Type R/CTR cams don't keep power up to 8800 rpm.
you drop a valves, probleme with valves to valve, valves to pistons clearance, or problem with retainers lock or broke valve spring
b20vtec with Type R/CTR cams don't keep power up to 8800 rpm.
you drop a valves, probleme with valves to valve, valves to pistons clearance, or problem with retainers lock or broke valve spring
Thread Starter
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Re: All Motor B20 Vtec BROKEN!! Please help
yes, his explanation was that the new BC Springs were too stiff/ tight for an oem honda belt. does this sound right?
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Re: All Motor B20 Vtec BROKEN!! Please help
up to 8800rpm, thats where it had been tuned to. surely the tuner would have set the limiter to a lower rpm if it was dangerous to go higher?
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