| Author | Message | ||
     Terp84alum |
Greeting folks, Newbie from MD here. Can someone point me in the right direction to find the technical specs for my heads? They are PN 16827-98YB and 16797-98Y. I put these on with the TS pistons (22676-98Y) and SE .551 cams. What I'm really interested in is the max lift that the heads will take. I am getting conflicting info. Thanks | ||
| Alessio66xb12r |
if you run thunderstorm pistons i hope for you those are thunderstorm heads. un possible give you an answer regarding max. lift , many things involved. anyway max. lift is not done by the heads . 1)you must check clereances(valve/piston) at tdc . 2)springs 3)cams 4)valve pockets exc. .................................................. .............never heard "this pair of heads will permit you a max. lift of..." | ||
| Pammy |
Allessio is correct. At any rate a 551 cam shouldn't cause any issues due to the heads(castings). Do you mean the springs? Are you concerned with coil bind? Valves hitting the pistons? Do you have the stock springs, retainers, valves, etc...? | ||
| Terp84alum |
I'm running the stock TS heads that came assembled. My concern is two fold: float (springs) and retainers hitting the seals/guides. I'm actually getting ready to pull the heads off this week so I'll have my answer. I just thought that there would be some info about this. It's pretty basic info with respect to the travel. Thanks for the replies. | ||
| Bad_karma |
Ken Check with Zippers they are in Maryland, maybe close enough for a face to face talk. Joe | ||
| Blake |
Better to check with any of our sponsoring performance shops. | ||
| Alex |
If You are talking about the SE Sportster Performance 04-08 cam (that´s the only one I know with .551" lift)I can tell You the following: You won´t have problems with valve clearance at overlap TDC, You won´t have problems with valves hitting the piston. But You will have problems with coil bind. The springs are not made to accept a .551" lift with enough safety clearance. You could machine the lower valve collar area to gain valve length but it will cost You spring pressure. I wouldn´t do it. The Performance 04-08 cams are basically the XB cams. They are made to work with the XB beehive springs which are also installed in the 04 up Sportster heads. They accept more lift while providing more spring pressure as the springs in the Thunderstorm heads do. So these cams are not made to be run with stock Thunderstorm heads (read: springs). Regards Alex M-TeK Engineering | ||
| Terp84alum |
Thanks Alex. I've been running the setup for about a year. The heads are supposed to come off this week. I'm heading down to the shop today to see if they're off. From there the heads are going to be reworked. I'm really not interested in buying new cams since these are less than a year old. Hopefully, after the headwork, I'll be good to go. Thanks again. |
