OK, did not know what a crane xr-1 is, pointless ignition?
Timing problem
Thread Starter
Race Director
Joined: Feb 2004
Posts: 14,984
Likes: 185
From: CT
Timing problem
Can't figure the timing on my 350-LT1 engine (Holley 750, Weiand Stealth Manifold, headers, stock 340-distributor with Crane XR-1). With dial-back light it shows about 32 degrees at idle and off-the chart at 3,500. It is a fully degreed balancer that has been on the car for years (rubber is good). With vac gauge at idle still indicates late timing. Starts right up with no effort, idles good and responds at throttle. If I put the timing back to 12-14 initial it barely runs.
Safety Car
Joined: Jan 2006
Posts: 3,663
Likes: 361
From: Smyrna/Vinings, Georgia
sounds like another thread, either your timing it from the wrong cylinder, not #1 or #6, or, your TDC line is not TDC anymore, or your camshaft is not properly timed with the crankshaft.
first thing simple to check. put #1 piston @ TDC and check your timing mark.
easy check on camshaft: put #1 piston @ TDC, remove valve cover, move the crank back and forth past TDC, #1 OR #6 valves will just open and close as you pass TDC. if you only want to remove one valve cover then crank might be 180 out. in other words @ TDC either #1 or #6 will be (firing) TDC, so the opposite one is the cylinder that would respond to the valve movement. maybe i am not too good explaining.
first thing simple to check. put #1 piston @ TDC and check your timing mark.
easy check on camshaft: put #1 piston @ TDC, remove valve cover, move the crank back and forth past TDC, #1 OR #6 valves will just open and close as you pass TDC. if you only want to remove one valve cover then crank might be 180 out. in other words @ TDC either #1 or #6 will be (firing) TDC, so the opposite one is the cylinder that would respond to the valve movement. maybe i am not too good explaining.
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Pro
Joined: Sep 2004
Posts: 694
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From: Children of the corn Illinois
Got one for you. new rebuild on a 382, single point vac adv dist. idles rough, but has a mellings RV cam. back fires like crazy when under load. If I ease into it, i can run 3000 rpm with out missing a lick, but if I give it a goose under load, if falls flat on its face and will not recover?