This is a discussion on SOUNDS LIKE VALVES HITTING within the Grizzly Talk forums, part of the Grizzly Forums category; Hello, new to sight and appreciate any help.
Just put a hot rod crank, Wiseco 11:1 piston with a stage 1 hot cam. I've aligned ...
Update, using a dial indicator on the intake valve side, with the cam fully depressed, the intake valves can be compressed .075 more until the valve hits the piston.
Aggravated, I took the head off to look for impact marks.
It looks like the center intake valve left a scuff or inprint, not a dent on the piston, even though it had .075 piston clearance.
Couldn't get the dial indicator on the exhaustside, but the valves could be depressed further until it hit the piston. Guessing at least .050.
Going to buy some clay and place it on the recessed piston reliefs and re-assemble.
is it a stroker crank? i have no first hand exprieance with the 660 but i have been told that the middle valve spring has to be replaced with a raptor valve spring on the 600 for a cam. im sure there are plenty of people on here with lots of 660 knowledge that will get you fixed up.
09 grizz 700, CP 11.5to1 tech piston, stage1 HC, pc5 with auto-tune and onboard LCD, barkers slip on, EHS intake system, EHS lid, mad mike clutch mod 2&3 with orange spring, stock weights, .5 shim, 26" Bighorn 2.0, Itp 112 wheels, oversized footpegs, warn 25xt, warn 60" pro vantage tapered plow.
08 raptor 700, Itp gncc holeshots, full gytr exhaust, gytr billet intake with k&n, protek airbox lid, tag bars, rox risers, full pro armor skids, pro armor bumper and grab bar
Thanks, the Hot Rod crank is stock, no stroker, didn't want any problems LOL. I just removed the valves thinking one of the three was different in lengths and I mixed them up, not.
It appears the Wiseco has a less recessed area in the middle valve compared to the outside valves.
i recently did the stroker and wiesco 11:1 cp and a mud buster cam i had no problems you do have to change the center intak spring to an 05 raptor spring if you are hitting you set some thing up wrong i would think when you set tdc did you have it on the compresion stroke and make sure you didnt mix up your valves exuast and the intake look the same but are alot diffrent from one another
__________________ 06 grizz 719cc (660) silver tip edition "YACC" member # 14 "660 ss " member #2 custom snorkels hotrods +4mm stroker crank hotcams mudbuster cam wiesco 102mm 11:1 cp piston port and poloished head 1.5mm shim hmf performance exuast brushed with blue tip 3500 lbs winch ebc brakes lights and angel eyes itp xls 27x10-12 front 27x12-12 rear dyno jet kit 175 main 8- 18 gr rollers orange epi secondary spring 500rpm stall springs
Last edited by eclipsemsj; 12-26-2011 at 07:48 PM..
The Following User Says Thank You to eclipsemsj For This Useful Post:
Rotate the engine counter clockwise to top dead center and make sure the 2 holes in the cam shaft are pointing straight up. If that's not a problem check the decompression pin to make sure it moves in and out when the weights are activated, if installed wrong it could be stuck open and cause valve problems.
The Following User Says Thank You to bulldog For This Useful Post:
Yes, it's at TDC using the middle mark of the three. You are right about the valves appearing the same. I did remove the 3 intake valves and measured the overall height, and they were the same. Are the exhaust valves longer than the intake?
I laid a piston sized clay disc about .200 thick on top of the piston and reassembled.
Starting at TDC, I rotated the engine 4 revolution in the CCW direction, that's to keep the back side of the chain tight.
Removed the head and found some interesting results.
There wasn't any piston clearance marks. none.
There wasn't any exhaust valve marks at all, none.
The only mark was the center intake valve, the thickness of the clay left between the valve and the head was .080, almost identical to my dial indicator measurement.
And I thought it was the center valve that left a mark on the piston.
eclipsemsj might be onto something with the Raptor spring.
It almost makes sense that with a weak valve spring, that the Hot Cam is hitting my center intake with enough force to over extend the strength of the spring, thus hitting the piston. Almost sounds feasible.
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