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I might have a chance to get a 37G cam at a good price. I am concerned that it is too much for a bagger with stock heads. Currently have 95 inch flattops, CV40 and Trapp 2:1. I am looking for passing power in the 65-90mph range and normally shift at 3500 or higher. I know the 21 and 26 are better suited for stock heads, but if any one has experience with the 37 in a bagger with stock heads I would like to hear from you...good or bad. thanks jeff
 

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i have 37g cams in my 99 dyna sport. although i used springs etc. the info with the cams says they are ok with stock springs. after gear drive roller rockers and springs on my 95" hsr 42, i really picked up power. after the programable daytona twin tech ign. modual it became a whole new engine. that modual made a world of difference. in my opinion those 37g's are great. i doubt you will get 90 hp without more than cams though. good luck on your build.
 

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Mtclassic said:
I might have a chance to get a 37G cam at a good price. I am concerned that it is too much for a bagger with stock heads. Currently have 95 inch flattops, CV40 and Trapp 2:1. I am looking for passing power in the 65-90mph range and normally shift at 3500 or higher. I know the 21 and 26 are better suited for stock heads, but if any one has experience with the 37 in a bagger with stock heads I would like to hear from you...good or bad. thanks jeff
You need more compression to make work well. The experts set the comp around 9.8. With stock heads (83 cc) and a Cometic 0.03 you should get to about 9.45 comp and 175 ccp. Without shaving the heads you won't get to 9.8. BigBoys does head porting for $300 and they set the comp as you need it. Food for thought since it's cold in some parts of the world anyway.
 

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Mtclassic said:
I might have a chance to get a 37G cam at a good price. I am concerned that it is too much for a bagger with stock heads. Currently have 95 inch flattops, CV40 and Trapp 2:1. I am looking for passing power in the 65-90mph range and normally shift at 3500 or higher. I know the 21 and 26 are better suited for stock heads, but if any one has experience with the 37 in a bagger with stock heads I would like to hear from you...good or bad. thanks jeff
They will work just fine in your setup. I have them in my '01 Ultra which I converted to a CV40. I also have the 95" setup with stock heads. You may not get maximum performance without some head work but how do you know what you're missing when you never had it to begin with. They certainly won't hinder your performance in any way. I am pulling extra weight as our Ultra is now a trike plus I put the 3.15 gearing in it for better cruising with lower rpm. We travel all over the country two up and loaded down with our gear. The thing pulls like a tractor. Another thing to remember, if you put them in now, at least you will have them if down the road you want to do head work. I'm very happy with them.
 

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any step forward is just that. what i have been hearing about the twin cam heads is that the exhaust size is ok. just that the intake needs to be a bit larger. given that. i suppose it is really about what you want from your build. what kind of riding do you do? that will direct you toward the combo that will work for you. what will work for a drag guy is not what will work for the cruiser. a real good example is that hack. what he needs will differ from what you need. but, any improvement is a step in the right direction. Go for it! i think my 37 gs are great.
 

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need more compression

I put 37G in the '04 FLHRCI 95" w/Flat Tops about 6K miles ago. I had 203's in it. I was looking for the same thing you are -- power to pass Two-up. Well, I really think the Heads and Compression have to be right like everyone is saying. The bike pulls great down low (so did the 203's). The 37G's pull stronger then the 203's in the mid range but they too fall off in the upper range. I still don't have the pull I'm looking for at 75-85 Mph. I'm thinking that part of the 37G upgrade has to be Heads and a 9.8 CR.
 

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37g

I have a similar set up as Jim T. 98 inch, flat tops, 2>1 pipes, 40CV, 37g.
While I lost a tad of "stump pulling" power in the low range I don't have need to pull too many stumps. The passing ability is awesome, almost as good as my Sportster (it was highly modified). You will be very happy with the 65 to 90 aspect. The heads are polished but not ported or flowed, springs and valves and rockers are stock. THE BIG POINT HERE is that the Daytona TwinTec ignition is an absolute necessity anytime you change cams. Jim and I can't stress that enough. I have a fxdx and there shouldn't be any difference in this advice for a bagger or softatil. One more time, if you change your cams you need the Daytona TT ignition. Well worth the extra bucks. It doesn't make it faster but it makes it so much smoother.

Have fun, Fred
 
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