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I don't recall over there but did you get your answer what,if any,optional gear ratios you have available?
I can only guess that when these guys discuss at the valve and at the cam they are not starting their degreeing at either .020 or .050 cam lift. That could be why he is seeing 20 degrees difference. The clearance ramps can be vastly different between cams and that is why the .020 and .050 became the standard.Eventually,most people I know went to lobe centerlines to further define cam timing since opening/closing numbers can be misleading when considering where max valve lift occurs. After you have fixed all mechanical issues you have such as air leaks and overall gearing then tuned it as best it can be if you are still unsatisfied I'd take his advice on the cam regrind. I agree with him on that for sure.
well i just retarded the timing 3* and no noticeable change on take off, audible change in sound of exhaust. i did advance it once and saw no diff but will do it again in a few mins and see. was watching the afr gauge and under boost i saw 11.5 to 12 then let off to level out so basically very low to off boost the gauge read 15.9 15. cannot find a leak even tried shooting windex on the joints on cold start up and warmed up.
ok so set back to 0 mark and advanced 4*.....exh sounds right again and no huge diff in take off. def better than retarding the cam!
How far from end of exhaust outlet is your O2 sensor?
This was mentioned in the other thread and caught my attention as well as the responder. That is bass akwards. If it were me,I know I would get a real degree wheel on the crank and verify there is not an issue with the cam lobes indexing to the key/dowel/whatever. If you can't get cam degree card to agree with what you find then there is your problem. That would advance/retard your cam perhaps a lot and be a plausible cause of your issues. Advancing the cam and possibly slightly seeing an improvement in take off would possibly indicate a way retarded cam and advancing it makes it more "right" and makes me think it is very possible. It's rare but it can happen since the cam ,if checked in QC, will likely only verify valve events of intake lobe in relation to the exhaust lobe. Rare,but anything is possible. Along that line of thought,is there any remote possibility the cam is installed one tooth off? Rare also,but anything is possible,we're human.
big pipe,close to the end=O2 reverting into pipe. Can you move it a lot further up?
i am positive it is not one tooth off. i even marked the belt and gear to easily make sure the belt didn't slip. i used a an end caliper with magnetic base and extension to cyl 1. found the beggining and end of tdc, rock over if you want to call it. measured between the marks and set tdc at that point and then zero'd out the cam using the method as speedway described which can be found on stinger, turbo ford etc etc. anything is possible but i have my doubts.on another note i can tell you that advancing the cam 8* sounds like retarding it 3* .......come to find out each mark on the cam gear is 2 * not 1. when i bought this aluminum adjustable round tooth timing gear set the ad said adjustable in 1* increments. well per the instructions.....each mark is 2* so not sure which one is correct! also all cam websites say advance to increase bottom end and retard for top so i think speedway got that part wrong. before i realized this a couple weeks before st a trip ( the timing marks that is) i did start the motor and run it twice. not 7k rpm pulls just runs. so anyways i can say that at 8* it makes the exh sound just like when retarded 3* so at 0 to 4* advnced is the better area.