Head work
Road Master
Joined: Jan 2008
Posts: 853
Likes: 5
From: Mnpls MN
head work will get you more performance. You may as well do the 103 just like Black 3 said. It's not that much more and you will not regret it. Besides, when you pull the heads off, you have to ring the pistons anyway, so just bite the wallet and get the 103.
Tourer
Joined: May 2009
Posts: 432
Likes: 2
From: SW of Fort Worth
Head work will help you for sure. You will want to have it dyno'd afterward. Personal opinion, I would go with one of the auto-tuners out there. That way, you can make subtle changes to you configuration without having to do another dyno.
I would get with one of the performance shops who hang around this forum like Hillcity and let them guide you. They can do your heads with a plan for the future.
If you do decide to go with a bigger bore, don't mess with just doing a 103. Do a 107. I went 103 and regret it everyday.
Frankly if it were me. I wouldn't do heads first. I'd go bigger bore.
A friend of mine has the following plan:
He changed his barrels to 107 by Axtell.
He used their flat-top pistons with stock heads for now. He's running just under 10 to 1 CR. He put in a Woods 555 cam. Then he purchased a ThunderMax autotuner.
Phase 2 will be Stage 3 head work, 54 mm TB, higher CR (10.5 to 1) with automatic compression releases; and a 2 into 1 Fat Cat and clutch spring. He'll have an option of keeping the cam or going to something else.
Think about it. That's going to be a nice motor when its all done. But he gets to build it in two phases spreading out the cost.
Just thinking out loud.
I would get with one of the performance shops who hang around this forum like Hillcity and let them guide you. They can do your heads with a plan for the future.
If you do decide to go with a bigger bore, don't mess with just doing a 103. Do a 107. I went 103 and regret it everyday.
Frankly if it were me. I wouldn't do heads first. I'd go bigger bore.
A friend of mine has the following plan:
He changed his barrels to 107 by Axtell.
He used their flat-top pistons with stock heads for now. He's running just under 10 to 1 CR. He put in a Woods 555 cam. Then he purchased a ThunderMax autotuner.
Phase 2 will be Stage 3 head work, 54 mm TB, higher CR (10.5 to 1) with automatic compression releases; and a 2 into 1 Fat Cat and clutch spring. He'll have an option of keeping the cam or going to something else.
Think about it. That's going to be a nice motor when its all done. But he gets to build it in two phases spreading out the cost.
Just thinking out loud.
Last edited by HardyHarHarley; Apr 24, 2011 at 08:40 AM.
Grand HDF Member
Joined: Aug 2009
Posts: 4,212
Likes: 1,776
From: USA
Head work will help you for sure. You will want to have it dyno'd afterward. Personal opinion, I would go with one of the auto-tuners out there. That way, you can make subtle changes to you configuration without having to do another dyno.
I would get with one of the performance shops who hang around this forum like Hillcity and let them guide you. They can do your heads with a plan for the future.
If you do decide to go with a bigger bore, don't mess with just doing a 103. Do a 107. I went 103 and regret it everyday.
Frankly if it were me. I wouldn't do heads first. I'd go bigger bore.
A friend of mine has the following plan:
He changed his barrels to 107 by Axtell.
He used their flat-top pistons with stock heads for now. He's running just under 10 to 1 CR. He put in a Woods 555 cam. Then he purchased a ThunderMax autotuner.
Phase 2 will be Stage 3 head work, 54 mm TB, higher CR (10.5 to 1) with automatic compression releases; and a 2 into 1 Fat Cat and clutch spring. He'll have an option of keeping the cam or going to something else.
Think about it. That's going to be a nice motor when its all done. But he gets to build it in two phases spreading out the cost.
Just thinking out loud.
I would get with one of the performance shops who hang around this forum like Hillcity and let them guide you. They can do your heads with a plan for the future.
If you do decide to go with a bigger bore, don't mess with just doing a 103. Do a 107. I went 103 and regret it everyday.
Frankly if it were me. I wouldn't do heads first. I'd go bigger bore.
A friend of mine has the following plan:
He changed his barrels to 107 by Axtell.
He used their flat-top pistons with stock heads for now. He's running just under 10 to 1 CR. He put in a Woods 555 cam. Then he purchased a ThunderMax autotuner.
Phase 2 will be Stage 3 head work, 54 mm TB, higher CR (10.5 to 1) with automatic compression releases; and a 2 into 1 Fat Cat and clutch spring. He'll have an option of keeping the cam or going to something else.
Think about it. That's going to be a nice motor when its all done. But he gets to build it in two phases spreading out the cost.
Just thinking out loud.
This "If you do decide to go with a bigger bore, don't mess with just doing a 103. Do a 107" Agree- Is it the 107" is still somewhat unknown or do people simply think HD only as their upgrade path?
Tourer
Joined: May 2009
Posts: 432
Likes: 2
From: SW of Fort Worth
Pops,
You are right on. Some folks never get out of their HD dealer enough to know there is a life outside their walls.
Man do I wish I'd gone another route instead of my 103. Don't get me wrong, my 103 runs real good. But the 107 build I have in the back of my mind would be very hard to beat without splitting my cases.
Jim
You are right on. Some folks never get out of their HD dealer enough to know there is a life outside their walls.
Man do I wish I'd gone another route instead of my 103. Don't get me wrong, my 103 runs real good. But the 107 build I have in the back of my mind would be very hard to beat without splitting my cases.
Jim
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Elite HDF Member
Joined: Jun 2008
Posts: 4,109
Likes: 9
From: Connecticut
I did mine to a 103" this winter and have to agree togo to a 107 and be done with it. I got the cyl and pistons real cheap so I went that way for now. I plan now to have the old ones bored to 107and have the heads done to match with new cams but this will happen when I get more $$. I also bought a set of used heads and had those done with cr's and a mild port job. Unless you plan to keep ripping it apart then do a 107" then do the heads when you can.
I did mine like this as I like to play and put together a combo that I thought would work and so far it works real nice
I did mine like this as I like to play and put together a combo that I thought would work and so far it works real nice
Last edited by Blk and Chrome; Apr 24, 2011 at 08:41 PM.
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