Engine overspeed by downshift
#1
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Engine overspeed by downshift
Will accidentally shifting to an inappropriately low gear damage something? This can occasionally happen when I'm on the 5th gear, slow down to negotiate a turn, and want to shift to 3rd gear while inattentively shifting to 1st gear.
What part of the engine will be damaged by this move? Rods, main bearing, transmission, or anything else?
How to prevent this kind of overspeed?
Thank you.
______________________________
By the way, I'm talking about a stock 4G63T with some insignificant bolt-ons, such as aftermarket intercooler, various gaskets, and head studs.
What part of the engine will be damaged by this move? Rods, main bearing, transmission, or anything else?
How to prevent this kind of overspeed?
Thank you.
______________________________
By the way, I'm talking about a stock 4G63T with some insignificant bolt-ons, such as aftermarket intercooler, various gaskets, and head studs.
Last edited by Serbj; Apr 18, 2011 at 04:19 PM.
#3
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Valvetrain problems are your biggest issue. Could weaken the springs and cause a valve to fall into the pistons over time...
Try not to shift into 1st, when you mean to go into 3rd...
Rod bolts will be damaged but I would be more worried about that if they were under load, in this case they were not.
Mikey
Try not to shift into 1st, when you mean to go into 3rd...
Rod bolts will be damaged but I would be more worried about that if they were under load, in this case they were not.
Mikey
#4
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Okay, so it damages the valvetrain and rod bearings. That sounds critical to the engine and it may not last long if this happens often.
I'll try hard to shift to the right gear... hehe
I'll try hard to shift to the right gear... hehe
#6
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Its not quite as bad as say a 1-2-1 shift persay when racing but you should still avoid it altogether. From my experience the valves will hit the pistons and all hell breaks loose as you can imagine. I had just turbod my honda and installed a b&m short shifter, wasn't use to the new feel of it, and did a pull. Wot in first snatched second bout 6500rpms snatched what I thought was third dumped the clutch and bout went through the front window as my motor went well into the rpm range of a crotch rocket. When I tore it apart it had broken 2 valves bent 3 more and had a nasty hole in a piston and another was beat to crap as well.
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