Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[crazyhorse223]

gettin ready to assemble a 103  with flat top pistons , mva heads and t-max auto - tune and  258 cams.anybody have this setup.looking to break 100 hp and same #'s  with torque.looking for input,thanks.      forgot this will be built on a 96" motor. mind fart.

[Mr D]

gettin ready to assemble a 103  with flat top pistons , mva heads and t-max auto - tune and  258 cams.anybody have this setup.looking to break 100 hp and same #'s  with torque.looking for input,thanks.      forgot this will be built on a 96" motor. mind fart.

 

[Mr D]

gettin ready to assemble a 103  with flat top pistons , mva heads and t-max auto - tune and  258 cams.anybody have this setup.looking to break 100 hp and same #'s  with torque.looking for input,thanks.      forgot this will be built on a 96" motor. mind fart.

The mind was on fast forword, My apology 
IMO... That SE 258 grind is a big cam for what you're looking for, there are much better choices available for your set up. alot of riders have had good results with the CVO 110 cam (SE 255) in a 103 build... Very good usable torque... A member here (HERKO) has this set up in his bike and resulted a reliable, fun driving machine.

[HD Street Performance]

Hitting a number is one goal, and having large average numbers over a wide range is another.
These are big heads, on a relatively small motor with a long duration cam with a lot of overlap and flat top pistons with a 97cc chamber (low compression). The weight and model of the bike and year we don't know but that could even make it worse.
This is a recipe for a late to bloom lazy low end torque build. It will take a lot of gear shifting to keep in the RPM band and won't be a lot of fun.

[Mr D]

Hitting a number is one goal, and having large average numbers over a wide range is another.
These are big heads, on a relatively small motor with a long duration cam with a lot of overlap and flat top pistons with a 97cc chamber (low compression). The weight and model of the bike and year we don't know but that could even make it worse.
This is a recipe for a late to bloom lazy low end torque build. It will take a lot of gear shifting to keep in the RPM band and won't be a lot of fun.

Well said Don...

[crazyhorse223]

thanks for the input.this will be put to the test on a 2010 Dyna wide glide. but 1 consideration won't the thunder-max with the auto -tune be able to compensate for the laziness at low rpm's ?

[HD Street Performance]

No
You have a set of mechanical components that generate low cylinder pressures at lower engine speeds. All the software will do is assure you have a proper air/fuel ratio and that said it takes user input to assure that condition.

[crazyhorse223]

so too make this combo work different pistons would be the answer ?

[Unbalanced]

I think the answer here is compression / and the right squish, but if the heads are off to get compression why not have them fluffed at least /shrug

I was looking for more stock head posts.  If you are a member on htt you can see these dynosheets.  Until you get some more compression and even with it it it can be tough to get the 100/100 or more with bone stock heads.

http://harleytechtalk.org/htt/index.php/topic,26287.0.html

http://harleytechtalk.org/htt/index.php/topic,23056.msg237030.html#msg237030

http://harleytechtalk.org/htt/index.php/topic,21595.msg221136.html#msg221136

http://harleytechtalk.org/htt/index.php/topic,16004.msg160938.html#msg160938

http://harleytechtalk.org/htt/index.php/topic,928.msg7361.html#msg7361

[HD Street Performance]

so too make this combo work different pistons would be the answer ?

More compression absolutely
Pistons not needed, you have native 9.8/1 with the stock heads and 103" so why not mill them some, choose a more appropriate cam, and have the heads ported. You will have a lot more torque under the curve where we typically ride and a much more fun ride.
BTW those MVA heads have enough airflow to support a 124" handily and are just flat overkill IMHO