My 103" project will begin soon and would like some thoughts about minimum head work to be done when the time comes. The bike is a 2009 FLHT with 6000 miles on the odo. The build will consist of 103" flat tops/Andrews 54H/.030 top end. My a/c is a SE Ventilator, stock head pipes with Jackpot dyno slip-ons and SEPST tuner. I honestly don't anticipate any equipment change for a few years to come. I ride solo 99% of the time and weigh about 215#. My riding style does vary greatly with bursts thru the gears to usually no more than lower 5k rpms but most of the time it is normal range cruising. I usually keep my cruising rpms in mid/upper 2k range and don't use 6th gear until 70mph>. My initial thoughts at minimum are good multi angle valve job (new guides/seals), equalizing CC's, intake bowl clean up and Singh grooves. Is any more required/recommended as I described. Wonder about 1.90 intake valves or more CC'ing for compression? Just looking for thoughts from those that know... Thanks

 

You can rework the heads to accomodate the 1.90 valve, but I don't believe you can go any larger without changing out the seats. Your porter will need to rework the throat to match the larger valve, and the intake port will need a little work to handle the increased flow. You have to do it all, or there's no performance gain to be had just putting in the larger valve. I'm sure your head porter will go over all of that with you.

As far as setting your chambers for proper compression, I'd just let them know which cam you're running, and go no more than about 9.2 corrected. I like solid pushrods whenever possible, keep track of how much comes off the heads and you have the option of running the perfect fit pushrods.

I'm not sold on squish grooves, but I could go either way. There's no real downside to them other than the cost, which is minimal. The theory is that they promote better combustion, but I haven't seen any quantifiable proof as to their effectiveness. If they do work as suggested, they would make the bike easier to tune. If they don't work, it's no real loss. I just wonder if they are one of those internet forum things where someone claims they make the engine work X-percent better and it gets picked up and repeated. I don't really know, and I suspect lots of head porters don't really know either. I don't care much for snake oil, and that's what this one feels like to me.

 

Yeah, I'll be making several calls this week. Thinking a 1.90 intake/stock exhaust and some intake bowl clean-up. It sounds like the 09 heads flow not too awful bad. With the .030/54H, CC at 85 the charts show 10.14:1 static, 9.26:1 corrected and 187.4 ccp. That sounds about where it needs to be. Like you stated, haven't seen any cons with the grooves and in correspondence, porters basically include them if requested. I think I've narrowed it down to 3 out of state and 3 local. Sending them out will add about $60 for shipping but if it feels good so what. Oh yeah, I do have manual cr's to be tapped in

 

I'm sure you mean cc at 85.

 

Is their something wrong with 12.66:1 static/11.55:1 corrected/254ccp ? Yeah, typo error