Piston clarence problem
#1
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Location: Desert Hot SPrings CA
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Car: 85 Z51 Corvette
Engine: LS1
Transmission: Manual 4+3
Axle/Gears: Dana 44 3.73
Piston clarence problem
Combination:
71 350 4 bolt 3970010 "010"
L98 heads
H345NP speed pro pistons
Crane cam .464''/.464'' 222°/226°
Eagle ESP Cast Steel Crankshaft
Performer rpm intake
holley Commander 950 Throttle Body 700cfm
65 PPH injectors
Arp main bolts
Crane Cams Aluminum Rockers 1.5
Federal-Mogul Performance Pushrods
Eagle ''SIR'' I-Beam Connecting Rods
The problem is the Vavles hit the pistons. Luckly i found this out before I ran it, could i have done something worng. I have installed cams befor and cant see how u can screw it up. Could the 58cc heads been decked to much I did get them from a rebuilder at pomona swapmeet they are awsome looking heads espcially for $350. Can I just relief the pistons. Please help
71 350 4 bolt 3970010 "010"
L98 heads
H345NP speed pro pistons
Crane cam .464''/.464'' 222°/226°
Eagle ESP Cast Steel Crankshaft
Performer rpm intake
holley Commander 950 Throttle Body 700cfm
65 PPH injectors
Arp main bolts
Crane Cams Aluminum Rockers 1.5
Federal-Mogul Performance Pushrods
Eagle ''SIR'' I-Beam Connecting Rods
The problem is the Vavles hit the pistons. Luckly i found this out before I ran it, could i have done something worng. I have installed cams befor and cant see how u can screw it up. Could the 58cc heads been decked to much I did get them from a rebuilder at pomona swapmeet they are awsome looking heads espcially for $350. Can I just relief the pistons. Please help
#3
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Join Date: Aug 2001
Location: Pacific Northwest
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Car: '85 IROC
Engine: LB9
Transmission: 700 R4
#H345P pistons have reliefs, but I didn't see a #H345NP.
I'd look at the cam timing to be sure that's correct, because with the cam you have, I'd expect it to clear.
Do you have really large intake valves?
I'd look at the cam timing to be sure that's correct, because with the cam you have, I'd expect it to clear.
Do you have really large intake valves?
#4
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Location: Loveland, OH, US
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Car: 4
Engine: 6
Transmission: 5
There's no way in Hades you have a P/V clearance problem. Your cam is like .250" short of that. Milling the heads can't possibly move things that far.
You have an assembly malfunction. Sounds to me like you're trying to time off of the wrong "dot" on the crank gear.
Check your timing set installation. Set the crank to #1 TDC, and set the cam to where the dowel pin is at exactly 9:00 viewed from the front. The "dots" should both be very near 12:00, which is #1 firing. Alternatively, if you put the cam dowel at 3:00, the "dots" should be together (crank at 12:00, cam at 6:00) which is #6 firing.
You have an assembly malfunction. Sounds to me like you're trying to time off of the wrong "dot" on the crank gear.
Check your timing set installation. Set the crank to #1 TDC, and set the cam to where the dowel pin is at exactly 9:00 viewed from the front. The "dots" should both be very near 12:00, which is #1 firing. Alternatively, if you put the cam dowel at 3:00, the "dots" should be together (crank at 12:00, cam at 6:00) which is #6 firing.
#5
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Car: 85 Z51 Corvette
Engine: LS1
Transmission: Manual 4+3
Axle/Gears: Dana 44 3.73
I had the crank gear lineded up with the worng mark turns out it has 3 different postions it can be at. I had it linded with the trangle key instade of the sqaure. I guess the timging chain set is made for differnt degrees. All better now, the motor is all done. All i have to do is rebuild the tranning and in the car it goes. Thanks for the help
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