Hi guys, I was told by my builder, as I'm planing on changing rockers, in a couple months, to go to .175 lift, just curious, what will I expect from that, I've seen .165, etc, not sure what the numbers represent, and what to expect? also crank lifters down more? etc? he gets in Monday, just figured someone could answer as my expectations are at zero, lol, thanks, also I've seen other brands, Ultima? Revtech? etc are they up to task, or stay with SE? thanks, build in 107ci, 10.1 cp, info in sig.thanks

 

Lift will increase from .570" to about .600" and it will depend on the "actual" not advertised ratio. HD says 1.65, S&S says 1.64 and Andrews says 1.63. More knowledgeable folks than me predict 2-4 TQ/HP from the swap with a good tune, providing that the additional lift is not limited by other modifications. I have read posts where installing the higher ratio rockers actually dropped TQ/HP a bit. If I was to try it, I would try on the intake only but the only way to know if there was a gain would be a visit to the dyno and buying time for a couple of pulls. The marginal predicted increase is within the variance margin that could show between dyno runs on the same motor, even in the same day, so even if there is a slight increase in power, one can't be certain it was the result of the higher ratio rockers.

Personally, I would not invest the time and money to find out and if looking for more power, I would be looking at another cam set, advancing the current cam set 4* or perhaps boring or replacing the throttle body. JMHO

 

Splitting hairs if it works.

 

I've used them with good results with 37's.
Your lift will be around .605 and that's past the stock valve spring likings.

 

Not pissing in your Cheerios but on what do you base "good results"? Please share how you came to that conclusion.

 

After 47yrs of riding I can feel improvements when I do mods to my bikes.
It's Sop but it's still there. I have a T-Max and didn't put it on a dyno for a before and after. I've heard some cams/builds don't react so well. Mine did.

 

a lot depends upon whether the heads can take advantage of the extra opening. and as was brought out, the engine is a system and if parts do not play well, then you are at a loss.
as far as adv/retard cam timing, i doubt you will feel anything diff. a cam profile is a cam profile and by adv timing, the peak will dial in earlier and if you retard it will shift up the rpm scale. i run retarded and the power peak is 500 rpm upscale from straight up timing. why did i do this, well, i built it for top end and the shift puts more of the band where i need it. would i lose some low end, yep - but, the trans is geared down to increase torque so in the end i actually come out ahead. i run int'l gearing so i need all i can get before dropping 5th and get a 500 rpm cut. i cruise 70 @ 3k. the speedo is history dropping 3rd.

 

ID LIKE TO GET IT all right, meaning, I read the writeup on cams and how they work, I feel the stock size intake is to smalll, Hillside left stock, but I paid for throttle body porting, just haven't heard back what exactly was done,I know it wasn't opened to 52 mm, which well, ill leave alone, so here I am now, there was porting in rear I suppose,i need to know if I can use on say a new SE 52-54 mm throttle body? or its useless? etc...., I've been learning as I go, here and there, also proper pipe is important, this vance and Hines 2-2 big radius with baffles cut in half, is not exactly a performance pipe....im thinking 52-54 HPI throttle body, so not sure as of right now, I can keep, the rear, do they sell it separate etc? I have to look into this, new SE 54mm w/new injectors is just under 400$ ill grab the SE NP,hopefully porting I paid for can be utilized?...thanks in advance, id just want this to be as reliable as can be, and get the air flowing/pulsing properly, a good 2-1 for my build is killing, money NO OBJECT, ill be real clear on this.....lol....thanks

 

how does one advance current cams, I'm happy with the way they came on, I got short changed on opening of throttle body, now its gonna cost me 4 times, another day on that, but the advance? what does it advance the opening I believe is 40

 

Advance sprockets available from Andrews; 4*, so 40* would close at 36*.