pure_insanity Posted February 25, 2008 Report Share Posted February 25, 2008 ok, im running a tim c. monsta banshee roller cam with 1.6:1 rockers, yadda yadda yadda. ive got it degreed to 107 per tim c's specs with the cam via a shawn silva adjustable cam gear. the ignition timing ive got it set at is 10*btdc. it feels like it needs a bit more but im unsure. basically im just going on a gut feeling that it seems like the timing is too low. where do you think i should be running the timing? by the way this is a full rebuild so i shouldnt have anything out of spec or off a tooth or anything like that. as in, i dont think there is any problem other than where i have the timing set at. Link to comment Share on other sites More sharing options...
Shelby Posted February 26, 2008 Report Share Posted February 26, 2008 cam timeing will effect the point of when the cam realy starts to perform,,a little late and you'l see more low end power,, more advance'd will cut back the low end responce an improve the top or upper rpms performance by that number i guess your refering to the center of the valve over lap right , what was the exact degree of intake start of valve opening , from actual and the card specs , and how did you get an exact reading with hyd lifters on the roller arms , i found them to not hold but leak down makeing an exact reading nearly imposible unless you bottom'd the hyd lifter and use'd feller gauges to zerror lash the rocker not finding fault just asking questions Link to comment Share on other sites More sharing options...
pure_insanity Posted February 26, 2008 Author Report Share Posted February 26, 2008 shelby, i used feeler gauges to zero lash the adjusters, as you had suggested to me. im actually trying to find more of where i should set the dist. to give the right timing. think i may have been wording things poorly. Link to comment Share on other sites More sharing options...
Shelby Posted February 26, 2008 Report Share Posted February 26, 2008 lol ic ,, the dist position shouldn't have move'd all that much , start with doing it the same as always and go from there, if you mean the actual timeing BTDC,,use 10btdc same as befor , as always it's the max timeing advance you have to worry about 36-38 btdc max @4k Link to comment Share on other sites More sharing options...
Tim_C. Posted February 26, 2008 Report Share Posted February 26, 2008 I would put it at 14 degrees BTDC and see how that runs. If it is too much, back off 2 degrees. What do you mean by using a feeler gauge to 'zero lash' the adjusters? There should be absoutely no lash, and in fact a minimum of .15 of 'preload' (opposite of lash) on the lifter at all times, including off of the cam lobe. Any lash (gap) at any time can damage things. Maybe I am misunderstanding what you mean? Link to comment Share on other sites More sharing options...
Shelby Posted February 26, 2008 Report Share Posted February 26, 2008 what he is saying Tim is for checking the cam timeing you have to fully colapse the lifter and then remove all lash with feller gauges ,,this stops the lifter bleed down so you can get an acurate reading on the dial indicator that you can trust and duplicate Link to comment Share on other sites More sharing options...
Indiana Posted February 27, 2008 Report Share Posted February 27, 2008 set the lash so you get the duration that cam was ground for then find the center of those two points, find tdc then move your cam gear to correct, using zero or some flat stated # someone else was able to use has nothiing to do with the wear and parts in YOUR motor and every motor is going to be slightly different http://www.b2600turbo.com/degree_your_cam.htm if you disagree with anything I posted about this then say so, it works and its simple and it costs but a couple bucks to do it for the price of a plastic protractor + your time and if you don't like how your cam responds in your car when you do set it up then you need a different cam not a different center line that screws your cam up from the way it was ground and intended to be used Link to comment Share on other sites More sharing options...
Shelby Posted February 27, 2008 Report Share Posted February 27, 2008 humm, ok so i get a cam say from Tim or tep,, on the spec sheet it says intake opens @ 24ATDC and closes @70 ABDC this is just for an exampleonly,if i set the cam so the intake valve start's to open at exactly 24ATDC would i not in fact have the cam in time as it was ground to be , not all cams are ground to be center line'd on over lap maybe i'm all wrong but my point of advancement or retarding starts with the cam time'd to the card , then make changes if nessarry ,center line can be check'd after the cam is to specs Link to comment Share on other sites More sharing options...
pure_insanity Posted February 27, 2008 Author Report Share Posted February 27, 2008 ok, you guys can go over my head way fast. im not as up on all this as you guys are so all i can say is thanks for all your help. thanks tim for a number to go on. thanks. Link to comment Share on other sites More sharing options...
Shelby Posted February 27, 2008 Report Share Posted February 27, 2008 ok wait befor you go,, what did you degree the cam to,, it's card setings or what to give you a better answer to your timeing question,, there are a lot of veriables to limit timing, what may work well for one guy maybe a little on the dangerous side for another ,,it's usually best to err to the safe side a little ,,the factory timeing was set up to be a middle of the road seting to cover all things so to speak,,it's not the best for power,,or fuel mpg but a middle ground for both to actualy find your limit you have to max it out till you break then back down, other then that i'd sugest you stay safe it's far cheaper Link to comment Share on other sites More sharing options...
pure_insanity Posted February 27, 2008 Author Report Share Posted February 27, 2008 i degree'd the cam to 107*. provided i understood and did it right , it should be correct. this is what the specs from tim.c say- to the best of my knowledge, i did it right. Link to comment Share on other sites More sharing options...
Shelby Posted February 27, 2008 Report Share Posted February 27, 2008 out of courosity how far from "0" did you end up moveing the cam gear pin hole Link to comment Share on other sites More sharing options...
pure_insanity Posted February 27, 2008 Author Report Share Posted February 27, 2008 to be honest, it was the first time i ever degreed a cam and i was a little nervous and maybe overwhelmed and forgot to pay attn to where it was to begin with. so i really dont know. it occured to me later that i should have payed attn, but at that point i already had the motor sealed up and didnt want to open it back up. Link to comment Share on other sites More sharing options...
Tim_C. Posted February 27, 2008 Report Share Posted February 27, 2008 what he is saying Tim is for checking the cam timeing you have to fully colapse the lifter and then remove all lash with feller gauges ,,this stops the lifter bleed down so you can get an acurate reading on the dial indicator that you can trust and duplicate Ahhh, yes. Link to comment Share on other sites More sharing options...
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