10.8:1 compression...which cam?
Thread Starter
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Stellar HDF Member
Joined: Nov 2007
Posts: 2,307
Likes: 53
From: California
Guys...first, let me say thanks for taking the time out to help. Next, I completely understand SE is not the best out there...I'm definitely not hung up on just SE, trust me. I just did it that way because this service manager said he would take care of me warranty wise.
Now that he gave bad advice on the build (yep, he told me what to get piece by piece right down to the p/n's), I'm thinking about having him make it right. But, I'm also thinking about cutting my losses and moving on.
What I WANT to do is a T-Man Stage III 103" build, but since the money situation is NOT the greatest right now (wife loss her job), I'm exploring less expensive ways that are still effective. I have NOT ruled out the T-Man 103" build as of yet.
I ride aggressive (come from dirt bikes and crotch rockets) and also use my bike as a daily commuter 65 miles one way.
I'm not a big number chaser, but it would be nice to have triple digits (or in the teens), but if I don't get there, I wont be upset. I would much rather have my bike running good and not have to worry about the longevity of it (I think this might be my last one for a while).
Forgive me, some of the terms you guys are using I don't understand. I can tear my bike down front to back, but I never tore into an engine big or small. Unfortunately, my dad was only a TV repair man...not a mechanic.
Thanks again.
Now that he gave bad advice on the build (yep, he told me what to get piece by piece right down to the p/n's), I'm thinking about having him make it right. But, I'm also thinking about cutting my losses and moving on.
What I WANT to do is a T-Man Stage III 103" build, but since the money situation is NOT the greatest right now (wife loss her job), I'm exploring less expensive ways that are still effective. I have NOT ruled out the T-Man 103" build as of yet.
I ride aggressive (come from dirt bikes and crotch rockets) and also use my bike as a daily commuter 65 miles one way.
I'm not a big number chaser, but it would be nice to have triple digits (or in the teens), but if I don't get there, I wont be upset. I would much rather have my bike running good and not have to worry about the longevity of it (I think this might be my last one for a while).
Forgive me, some of the terms you guys are using I don't understand. I can tear my bike down front to back, but I never tore into an engine big or small. Unfortunately, my dad was only a TV repair man...not a mechanic.
Thanks again.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
Don't throw a bunch more money at your bike as having the experience that you have will make even a 150hp Street Glide a bore, and that costs big bucks. I think I know where you are coming from and i agree with HDWRENCH that the 251's may be a very good choice to try (.579 lift) and a 2 into 1 exhaust(even with the T-Man) along with the proper tune should get you on track. Wish I knew some shop down in your area to steer you towards but I am in the Ventura area so I am no help to you on that. I have had some experience with the MX and the Roadrace arena, a 850 pound FLHX with 150hp yawn compared to a 450 pound rocket with the same HP . Don't get me wrong I love my Flhx but trying to make it something it's not reminds me of a saying that goes like this, Never try to teach a pig to sing, it is a waste of your time and you are only annoying the pig!
Road Warrior
Joined: Dec 2007
Posts: 1,270
Likes: 0
do what ya want its your bike.
T-Man products are top shelf and perform great.
what i would do is if you are really stuck on his parts i would not do it twice as i would wait until i could get what i want.
also i am pretty sure with the price he paid for his harley he could of had 2 jap bikes and a full set of leathers to go with it. no one on this board disputes the fact that the japanese bikes are not fast. but any harley rider could of afforded a jap bike if they wanted it .
its like buying a camaro instead of a honda civic.. ill take the camaro any day.
and if i wanted a sport bike i could afford any one i want and my choice would not be any of the top 4 i would buy a ducati.
T-Man products are top shelf and perform great.
what i would do is if you are really stuck on his parts i would not do it twice as i would wait until i could get what i want.
also i am pretty sure with the price he paid for his harley he could of had 2 jap bikes and a full set of leathers to go with it. no one on this board disputes the fact that the japanese bikes are not fast. but any harley rider could of afforded a jap bike if they wanted it .
its like buying a camaro instead of a honda civic.. ill take the camaro any day.
and if i wanted a sport bike i could afford any one i want and my choice would not be any of the top 4 i would buy a ducati.
Thread Starter
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Stellar HDF Member
Joined: Nov 2007
Posts: 2,307
Likes: 53
From: California
I don't have a part number for the pistons. They are the ones that come with the SE 103" Stage II kit (EFI models), so I presume they are the cast flat tops. The description calls them big bore flat tops.
Part Number for the kit is 27545-08.
Part Number for the kit is 27545-08.
Road Master
Joined: Jul 2005
Posts: 1,061
Likes: 5
From: Fort Worth TX
That is a cast flat top piston, now with with the valve size that is in that head and use of a high lift cam chances are the the valve will hit the piston. This is due to the cast piston having only valve pockets cut for stock size valves. Max lift on that without checking anything would be right at 585 for a safe number and a 590 should work?? with the se heads sometimes the retainer will hit the seal and crush it , whith a cam larger than they spec. Most times the spring will not coil bind. But the valve size being larger than stock is going to need to be checked.
With this head a forged piston should have been used that would have had larger valve pockets to prevent this issue to start with. The head is decked from the start so you have less height/ meaning your valves are closer to the piston to start with. Add in a high lift cam, bigger valves and cast piston = broke parts. You could enlarge the pocket on the piston to save money. Most times that works out fine, once in a while you will hit a void in the piston ( they are cast).
At this point you got lucky due to the fact the 255 has a extremely low TDC lift. 130/116. Again with a cast piston the specs will vary and that may have helped with this as well. No telling when dealing with the cast piston. Measure several sets and you will see the pockets move around a bit.
With what ever cam you get you need to look at the TDC and check that once installed. There are several ways to do this.
With this head a forged piston should have been used that would have had larger valve pockets to prevent this issue to start with. The head is decked from the start so you have less height/ meaning your valves are closer to the piston to start with. Add in a high lift cam, bigger valves and cast piston = broke parts. You could enlarge the pocket on the piston to save money. Most times that works out fine, once in a while you will hit a void in the piston ( they are cast).
At this point you got lucky due to the fact the 255 has a extremely low TDC lift. 130/116. Again with a cast piston the specs will vary and that may have helped with this as well. No telling when dealing with the cast piston. Measure several sets and you will see the pockets move around a bit.
With what ever cam you get you need to look at the TDC and check that once installed. There are several ways to do this.
Last edited by HDWRENCH; Dec 9, 2009 at 08:51 AM.
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Joe Kucinski
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
That's a good reason to find an expert to talk this through with, either on the phone, or in person! Each of us here can only give you suggestions and the more of us who reply, the more suggestions you will get. What you actually need is just one way forward! Your bike can be transformed with some expert help....