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Author Topic:   Mid Range power
jammin
Dirt Administrator

Total posts: 3279
posted February 13, 2001 08:19 PM UIN: 16262997
I am working on a few motors right now...taking a look at some stuff. I wanted to know what you guys think about head runner size in relation to compression for mid range. We all know we can kill our midrange with too much runner. But what I am thinking is that if your running an 11 to 1 motor that you could even be better off with some smaller heads. Velocity is definitely a need of circle track heads, which produce throttle reponse. If your only pulling 11 to 1, how much throttle response do you think you could have with say 220 darts...I think it would be too much, what do you think?

owracer
Dirt Maniac

Total posts: 103
posted February 13, 2001 10:30 PM
There are several things you are going to have to take into consideration here-port size,runner lentgh including the intake runner,valve size,cam profile, etc.. I don't think compression will have much effect on what you are looking for. Engine stroke and bore size also have an effect on how well an engine is capable off breathing.

sdhnc29
Dirt Full Roller

Total posts: 74
posted February 13, 2001 11:30 PM
What are you using for fuel ? Gas or Alky ? And what cubic inch are you working with ?

jammin
Dirt Administrator

Total posts: 3279
posted February 14, 2001 08:56 AM UIN: 16262997
small 355's on methanol...

maybe even a 327 eventually.

sdhnc29
Dirt Full Roller

Total posts: 74
posted February 14, 2001 06:31 PM
Jammin ,

A 355 w/220 Iron Eagles is a good combo . The 220 head works very well , but if you go with a 377 you will want the 230 heads . Alky engines like large runners , if you were running a 1/2 mile track then the 230's would work well on your 355 . I'm curious , why you are going so low on compression ? Ideally , you want to end up with at least 14:1 . You will be in shock by the torque increase over 11:1 . If you have any questions about this type of engine , send me a personal email or call my business (828)286-0780 (eastern time) ask for Steve . I'm not sure if I can post our business name on this site , but I am a professional engine builder located in North Carolina . If I can help in any way , feel free to call or write . Steve

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