Engine knock help...please
goatnipples2002
03-21-2005, 02:58 PM
I have an 86 fastback 4spd gt.....
I had a loud knock in my engine that was barely audible at low rpms but picked up at higher rpms. So I swapped shortblocks with an 85gt, I also installed a 260H K-kit from comp cam. So that's new lifters, cam, seals, locks, cam gear, springs and I got com pushrods too. I had the heads milled 0.015 and I replaced every gasket. Even enlarged the water holes on the head gasket just like the GM performance manual says (I have if you need), and I also gasket matched the exhaust ports as well as my exhaust manifolds.
Now with the 85 shortblock and all my mods the engine has a knock with a different pattern. Before the knock had no certain rhythm. Now it DOES have a certain rhythm AND it pours out a ton of smoke. I try to rev it to red line and it won't go past about 4500 rpms.
With the 85 and 86 the engine started up fine as if nothing was wrong then the knock would started.
I would really like to fix this so could anybody please help?
I had a loud knock in my engine that was barely audible at low rpms but picked up at higher rpms. So I swapped shortblocks with an 85gt, I also installed a 260H K-kit from comp cam. So that's new lifters, cam, seals, locks, cam gear, springs and I got com pushrods too. I had the heads milled 0.015 and I replaced every gasket. Even enlarged the water holes on the head gasket just like the GM performance manual says (I have if you need), and I also gasket matched the exhaust ports as well as my exhaust manifolds.
Now with the 85 shortblock and all my mods the engine has a knock with a different pattern. Before the knock had no certain rhythm. Now it DOES have a certain rhythm AND it pours out a ton of smoke. I try to rev it to red line and it won't go past about 4500 rpms.
With the 85 and 86 the engine started up fine as if nothing was wrong then the knock would started.
I would really like to fix this so could anybody please help?
goatnipples2002
03-22-2005, 09:49 AM
I have an 86 fastback 4spd gt.....
I had a loud knock in my engine that was barely audible at low rpms but picked up at higher rpms. So I swapped shortblocks with an 85gt, I also installed a 260H K-kit from comp cam. So that's new lifters, cam, seals, locks, cam gear, springs and I got com pushrods too. I had the heads milled 0.015 and I replaced every gasket. Even enlarged the water holes on the head gasket just like the GM performance manual says (I have if you need), and I also gasket matched the exhaust ports as well as my exhaust manifolds.
Now with the 85 shortblock and all my mods the engine has a knock with a different pattern. Before the knock had no certain rhythm. Now it DOES have a certain rhythm AND it pours out a ton of smoke. I try to rev it to red line and it won't go past about 4500 rpms.
With the 85 and 86 the engine started up fine as if nothing was wrong then the knock would started.
I would really like to fix this so could anybody please help?
ANYBODY?
I had a loud knock in my engine that was barely audible at low rpms but picked up at higher rpms. So I swapped shortblocks with an 85gt, I also installed a 260H K-kit from comp cam. So that's new lifters, cam, seals, locks, cam gear, springs and I got com pushrods too. I had the heads milled 0.015 and I replaced every gasket. Even enlarged the water holes on the head gasket just like the GM performance manual says (I have if you need), and I also gasket matched the exhaust ports as well as my exhaust manifolds.
Now with the 85 shortblock and all my mods the engine has a knock with a different pattern. Before the knock had no certain rhythm. Now it DOES have a certain rhythm AND it pours out a ton of smoke. I try to rev it to red line and it won't go past about 4500 rpms.
With the 85 and 86 the engine started up fine as if nothing was wrong then the knock would started.
I would really like to fix this so could anybody please help?
ANYBODY?
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