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cam question

R.Bingham said:
check out the Andrews 48H. IMHO it is the best 96in bolt in cam.
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Randall, Is the Andrews 48H a cam that will work well with the stock compression ratio pistons? Other than fuel/spark advance mapping, are there any other changes that need to be done. Is the rate of lift workable with the stock valve springs etc. Not looking for anything radical or something that will destroy my intake vacuum etc. I also would prefer chain drive.

Tks
 
Hoople said:
Randall, Is the Andrews 48H a cam that will work well with the stock compression ratio pistons? Other than fuel/spark advance mapping, are there any other changes that need to be done. Is the rate of lift workable with the stock valve springs etc. Not looking for anything radical or something that will destroy my intake vacuum etc. I also would prefer chain drive.

Tks
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Yes it works well with stock compression,springs ,etc. You will need to re-map your ECM though. No other changes need to be done.

Here is a partial list of the Andrews cams that even have the stock 07 and up cams listed.
ResizedAndrewsspecs.png


Here is a dyno sheet comparing the SE255 to the Andrews 48H.( called the Express in this dyno sheet,it was then a prototype)
09SGX1EXPRESSDOHERTYACTTSDDFATCATQBBAFFLE.jpg

As you can see by the chart down low it and the SE255 are pretty much the same but the 48H carries the torque and hp out further.

Randall
 
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Thank you Randall. Looks nice. But I am a little confused because when you look up the SE 255 kit in the HD/SE catalog, there is asterisk next to the kit that says "compression release may be required".

That makes no sense to me because this cam should have less dynamic compression than a stock cam due to the fact the intake valve closes later than stock. If anything it should crank easier not harder. Would you know anything about why HD/SE would say that?

Really needing compression release is an important fact to know up front.

Tks!
 
Hoople said:
Thank you Randall. Looks nice. But I am a little confused because when you look up the SE 255 kit in the HD/SE catalog, there is asterisk next to the kit that says "compression release may be required".

That makes no sense to me because this cam should have less dynamic compression than a stock cam due to the fact the intake valve closes later than stock. If anything it should crank easier not harder. Would you know anything about why HD/SE would say that?

Really needing compression release is an important fact to know up front.

Tks!
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I just checked the '11 SE Catalog and according to it the stock cams in '07-08 96in engines have a 30* intake close. The SE 255 has a 25* intake close. According to the Compression Calculator on the Big Boyz website the stock cam has a Cold Cranking Compression (ccc) of 182# in a 96in engine. A 96in with the SE 255 has a ccc of 185#. But when you put that SE 255 in a 103in like a lot of people do that ccc jumps up to 200#. That is why they say compression releases may be required. 103's from the factory come with compression releases stock as they use the same stock cam as the 96in and have a ccc of 196.2.
A 96in with the Andrews 48H will have a ccc of 182.8 which is very close to the stock ccc. The major difference is the lift and duration of the cam. You will not need compression releases in a 96in and you are at the ideal compression range for a great street motor.

Randall
 
Wow. Great info, Thanks a million for clearing that up.!.

One more question if I may. I know with flat tappet lifters (non-roller lifters) it is a must to install new lifters when installing a new cam. Will I be able to use my existing roller lifters without buying a new set? I also plan on taking off the cylinder valve covers in order to remove my rockers & pushrods. If I can avoid using the adjustable push rods, I would like to.
Tks!
 
Turk55 said:
That makes a lot of sense, I think I will stay with chain drive, now the only question will be S&S, WOODS, or ? and what size to go with. Thanks again to all for input. :D
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Check this:

Roller Chain Conversion white paper

Roller-chain Conversion - Harley Davidson Community

TQ

Hoople said:
One more question if I may. I know with flat tappet lifters (non-roller lifters) it is a must to install new lifters when installing a new cam. Will I be able to use my existing roller lifters without buying a new set? I also plan on taking off the cylinder valve covers in order to remove my rockers & pushrods. If I can avoid using the adjustable push rods, I would like to.
Tks!
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Hoople,

Probably, but why not change out the lifters while you have it all apart anyway? The "B's" are only about $100 for the set, and then you will have those done!

With respect to adjustable PRs, I am a fan of these. My philosophy is to disturb as few gasketed mating surfaces as possible when working on the engine. The adjustable PRs allow you to do the cam chest work WITHOUT disturbing the top end. Worth it in my book unless you already have leaking surfaces.

TQ
 
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TQuentin1 said:
The "B's" are only about $100 for the set, and then you will have those done!

TQ
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Thanks TQ. Your right. For $100 it is well worth it. For some reason I thought the lifters were like $60 each making the set ~$250. I don't know why I thought that.

The reason I wanted to stick with one piece push rods was because of all the posts you see about guys hearing noise and no one coming up with a conclusive adjustment procedure. All I read is "tighten them so many flats past being able to rotate them with your fingers" etc etc. What kind of adjustment is that. So many flats from ZERO lash is one thing, so many flats from finger rotation is another. A recent post stated the complete compressible distance of the lifter was .250". If that is true, that is the 1st piece of real information I have seen on the subject to date. Knowing that makes an accurate adjustment possible.
 
Hoople said:
Thanks TQ. Your right. For $100 it is well worth it. For some reason I thought the lifters were like $60 each making the set ~$250. I don't know why I thought that.

The reason I wanted to stick with one piece push rods was because of all the posts you see about guys hearing noise and no one coming up with a conclusive adjustment procedure. All I read is "tighten them so many flats past being able to rotate them with your fingers" etc etc. What kind of adjustment is that. So many flats from ZERO lash is one thing, so many flats from finger rotation is another. A recent post stated the complete compressible distance of the lifter was .250". If that is true, that is the 1st piece of real information I have seen on the subject to date. Knowing that makes an accurate adjustment possible.
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Hoople,

Check these out:

Adjusting Pushrods - Harley Davidson Community

Hydrallic Lifters - Harley Davidson Community

TQ
 
TQ, Thanks for linking me to those. That really helps with clearing it up. Adjustable push-rods it will be. They sure do reduce the work involved and possibilities for cylinder rocker cover leaks.!
 
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