Jyar123

I have a 98 5.7 LS that I am trying to put into my 67 camaro. I have cleaned the block had the bore honed cleaned all piston and put in new rings. I put in new camshaft bearings new rod and main bearings. I have installed new pushrods and rebuilt the lifters. Installed a LS1 hot cam and springs. When I turn the motor over without the plugs everything turns fine. As soon as I put the plugs in the motor shakes and seems to have a knock. I thought it was my Flexplate but after installing a new one and the same results. I am not sure what else to check. Any suggestions or ideas?