Cam change

Energy One

Bhawkins854

Member
I've got a 117 with heads done by Lee's speed shop in MN. Port polish, Comp cams spring and 2.06 intake valves. My chart says my max lift is only 625 with these heads 10:3:1 CR. I am running a S&S600 cam right now and want to try the red shift 626v2 cam. Wondering why my mMax lift is only 625, non emissions 117 straight from S&S came with a 600 and I see ppeople on this site running 650lift cams. Heads and jugs were both shaved to raise compression but still only at a 10:3:1 which is fairly mild still. Any good suggestionsfor cams? I will have to check piston to valve clearances obviously
 

john sachs

Well-Known Member
I've got a 117 with heads done by Lee's speed shop in MN. Port polish, Comp cams spring and 2.06 intake valves. My chart says my max lift is only 625 with these heads 10:3:1 CR. I am running a S&S600 cam right now and want to try the red shift 626v2 cam. Wondering why my mMax lift is only 625, non emissions 117 straight from S&S came with a 600 and I see ppeople on this site running 650lift cams. Heads and jugs were both shaved to raise compression but still only at a 10:3:1 which is fairly mild still. Any good suggestionsfor cams? I will have to check piston to valve clearances obviously
Call Lee and verify the lift limit. He may have the valves installed (installed height) to where the springs will only accommodate .625" lift.
Put some more compression in it and use a .595" Extreme cam. That will get you the good #'s. :2thumbs:
John
 

Bhawkins854

Member
I know Lee does some of the best work around here. You think I should have him cut some more off the heads/jugs eh? What CR do you think I should run John? Pretty sure the S&S 600 is a 600 exhaust and Intake, is that 595 a better cam in you're opinion? Red shift makes that cam? I heard you're another guy who knows his shit. I just want a different feel now, I've been running the same set up for 2 years and I'm tearing the top end down tmrw morning due to come oil consumption issues. Pretty sure oil is getting my the Rings.
 

john sachs

Well-Known Member
I know Lee does some of the best work around here. You think I should have him cut some more off the heads/jugs eh? What CR do you think I should run John? Pretty sure the S&S 600 is a 600 exhaust and Intake, is that 595 a better cam in you're opinion? Red shift makes that cam? I heard you're another guy who knows his shit. I just want a different feel now, I've been running the same set up for 2 years and I'm tearing the top end down tmrw morning due to come oil consumption issues. Pretty sure oil is getting my the Rings.
I would stay away from Redshift, and Woods. Their cams are noisy, and will beat the valve train to death. :bang:
Lee knows, as does Mike Roland ,and Bob Wright. They're in your area also.
Run the 595 Extreme cam, with compression in the low 11's , and your bike will rip. :2thumbs:
John
S&S 600 is .600" on intake and exhaust. The Extreme is .595" on intake and exhaust.
 

Bhawkins854

Member
I'll have to do some further investigation into what route I want to go. After taking the motor apart I was told from Lee that I was missing a oil ring!! I had no idea that SSW+ motors have a four peice oil control ring set up. I found one of the squiggly rings broken on my front cylinder and the peice got wedged into my crankcase breather and jammed one of my reeds open.. 10k miles on the build and it ran like a beast. I still can't believe that I missed those two rings, good thing I decided to take it apart I guess!
 

LA_Dog

Go Fast, Go Faster
I went with the TMan 625 cam for my 107 rebuild. Seemed to be the best one after reviewing all options, has a good RPM range and comes on early. Guys are pretty sharp at TMan and easy to talk to.

JMHO.. from what I've been learing (I'm no expert at all, by any means, so if any of this is mis-stated, this is my humble disclaimer) . It is not just about your Static Compression. You need to know what your Corrected / Dynamic Compression will be, and for that you'll need to plug in the numbers based on your cam selection. For example, you could have a static compression of 10.3:1 and if you don't take cam into the equasion, you could end up with a low Corrected Compression (the operating compression of the motor when valves are opening / closing). Say you end up running with a corrected compression of 9:1. Not too bad. 9.5:1 is typically the limit for pump gas and running cool. I'm probably going to be pushing it with 9.8:1

Plus, every cam you are looking at has an optimal static and corrected compression range. you'll want to make sure you set everything up for the cam to get the most out of it.

You also need to know your deck height and squish, and head chamber volume. A good shop should be able to get all of that for you.

Or you could go the easy route and drop in exactly the same cam other 117 owners here are running with good results. Or even easier still, listen to John S, because he knows his stuff on the SS motors.

Either way good luck with the build!


linky to my fav calculators:
Big Boyz Head Porting - Evo Compression and Displacement Calculator

Boost Compression Ratio Calculator

RB Racing Squish Band and Deck Height Calculator
 
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Olde Man

Active Member
Extreme Cam

Who makes the 595 Extreme cam. I would like to look at the technical info. Thanks
 

LA_Dog

Go Fast, Go Faster
Who makes the 595 Extreme cam. I would like to look at the technical info. Thanks
I think it is the Mid-USA 595E cam (Ultima) - John would know for sure. Here is the link in their catalog: Page 511 - Mid-USA 2012 Catalog

I don't see all of the numbers published for the cam, and if you need to call anyone at Ultima / Mid-USA with tech questions they shut down all means of contacting them for support so don't try. I don't understand that at all. :confused:
 

john sachs

Well-Known Member
Mid-Usa makes the 595 Extreme. It's part of their Powerhouse series of cams. Works great. You need to rev the motor to take full advantage.
Midwest makes the Ultima series motors, and parts. They don't handle the .595 Extreme cam.
Both in the St. Louis area.
John
 

john sachs

Well-Known Member
Good to know, thanks for clarification. I've seen this cam for sale on the legendmc's website and the grind numbers are published: Discount Cams for Evolution Motors from Mid-USA for Harley Davidson

I recalled that Mackie has a 595 Evo cam as well. What do you think about it compared to the Mid-USA 595? Dave Mackie Engineering: High-Performance Cam Shafts
No experience with Dave's Evo cams. I've used his .598" in several Twin Cam motors. They work well. I have experience with the 595 Extreme. It was /is my cam of choice in a lot of 107" - 117" S&S motors, if a customer is looking for top end performance.
There's a dyno sheet somewhere on this forum of one of my customers' Hell Bound Steel 117" bike. 117", my heads, 595 Extreme....... 139 HP. :eek:
John
 

LA_Dog

Go Fast, Go Faster
No experience with Dave's Evo cams. I've used his .598" in several Twin Cam motors. They work well. I have experience with the 595 Extreme. It was /is my cam of choice in a lot of 107" - 117" S&S motors, if a customer is looking for top end performance.
There's a dyno sheet somewhere on this forum of one of my customers' Hell Bound Steel 117" bike. 117", my heads, 595 Extreme....... 139 HP. :eek:
John
139.. woohoo. that's sweet. :2thumbs:

OK so I got a bit of *cough cough* crappy news to share. Looks like my machinist decked my heads .060. I had told him to not deck the heads yet but that got somehow lost in translation. Net result is smaller cc chambers and I'm looking at 11:1 static comp ratio with my planned 30 quench.

So that BLOWS it for using the TMAN 625 cam. With the 41 intake close ABDC that puts my corrected compression at 10.08 and cold cranking pressure at 212.2 :angry:

Now I'll either need to open up the head bowls to increase cc volume / get back to 10.5:1 static, or get a different cam with later intake close like 50 that will work with the 11:1, and maybe a longer duration. I had selected the TMAN cam based on the early intake close and shorter 244/246 durations to keep the power band efficiency / max torque in 2000-5500 RPM range, a majority of my riding.

Amazing how one small mistake effs everything up. Happy Monday. :spank:
 

LA_Dog

Go Fast, Go Faster
thx - temporary setback, nothing a few more bucks and additional time won't fix (ain't it always like that). ;p

I hope the OP got his cam selection ironed out.
 

Bhawkins854

Member
Yeah I ordered the redshift 626, I hear it's a good torque cam and it's actually not too hard on the valve train, although iI hear it from both sides. I guess I was wrong with my CR.. It's at 10:5:1 which is OK for me, I don't think I want to push my compression too far I've already got 200psi in the cylinders, and my piston to valve clearances will be closer yet after this, probably going to have to take a little more material out of the relief pockets. Hopefully I like the cam!
 

LA_Dog

Go Fast, Go Faster
Yeah I ordered the redshift 626, I hear it's a good torque cam and it's actually not too hard on the valve train, although iI hear it from both sides. I guess I was wrong with my CR.. It's at 10:5:1 which is OK for me, I don't think I want to push my compression too far I've already got 200psi in the cylinders, and my piston to valve clearances will be closer yet after this, probably going to have to take a little more material out of the relief pockets. Hopefully I like the cam!
Cool- My mechanic really likes the RS cams, he's running one in his "frankenstein" 124" Dyna tht puts out an ungodly amount of power. I took it for a test ride and I thought I was on a damn Hyabusa, that bike will really wake your ass up :up:

So what you need to consider is your dynamic cam corrected compression. Static is only good while the bike is turned off. the cam dictates what your running compression will be, and it is important to get that right. Too low, no power. too high, ping / detonation. From what I know the "optimal" corrected compression for pump gas should be 9.2. below 9 is too low, above 9.5 have to be careful on tuning to avoid ping / detonation.

If your CR is 10.5:1, your cam corrected CR is about 9.0:1 and the cranking compression will be about 183psi @500ft above sea level - this is based on the 626's intake cam close timing of 54. So that is a safe margin but you will be leaving some power on the table. Raising your static compression a bit to say 10.75 to 11:1 will net you more power - But also keep in mind that this cam will not come on until you're getting into 3k RPM.

Here is a good calculator so you can play with the compression numbers:
Big Boyz Head Porting - Evo Compression and Displacement Calculator
 
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LA_Dog

Go Fast, Go Faster
also- how are you determining that you have 200psi cranking pressure right now? that is more now than you'd have after the RS cam change.

also I'd be cautious modifying the pistons, that will change the balance of the bottom end (usually you'd have the crank balanced with pistons on it) so I' not sure what tht would do. It may be better to have the heads worked if you need volume enlargement, but it sounds to me like if anything you'd need to raise compression for that cam.

Keep in mind you could look at cams that are already built for max TQ/HP based on your current static 10.5 CR- that would save you some extra $ by not having to do head work or otherwise mess with changing your CR.
 
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Bhawkins854

Member
200psi with a compression tester, with carb butterfly wide open. Takes about 4-5 engine rotations to get to 200psi. The only reason I had to open the piston relief pockets are for the oversized valves, and that my jugs and heads were both decked. The piston pockets are machined for the stock 2.00 Intake valves and after claying my heads the valve to piston clearances were dangerously close at about. 030 if I'm not mistaken(it's been a while since I've had the motor apart) I asked Lee how it's going to work with a cam with more TDC lift and he said it could usually be taken from the piston relief pockets which have already been opened... This is why I don't want to shave any more material from the heads or cylindeds. My buddy was building a 107 and his valve to piston clearances were miles further than mine, that's how I don't quite understand how I could deck anything further, and how people can have11:1+ static CR with this same motor.
 

Bhawkins854

Member
Also I'm an electrician by trade, I w
Put this motor together with my buddy that is a machinist, pretty sure he took. 050 off the jugs to get this emissions motor back to what the crate motor would have had, and. 020 off the heads along with Comp cams beehive Springs, 2.06 intake valves, and a port and polish. He calls it "pro Street ported heads".. Supposed to be the best he offers
 

LA_Dog

Go Fast, Go Faster
200psi with a compression tester, with carb butterfly wide open. Takes about 4-5 engine rotations to get to 200psi. The only reason I had to open the piston relief pockets are for the oversized valves, and that my jugs and heads were both decked. The piston pockets are machined for the stock 2.00 Intake valves and after claying my heads the valve to piston clearances were dangerously close at about. 030 if I'm not mistaken(it's been a while since I've had the motor apart) I asked Lee how it's going to work with a cam with more TDC lift and he said it could usually be taken from the piston relief pockets which have already been opened... This is why I don't want to shave any more material from the heads or cylindeds. My buddy was building a 107 and his valve to piston clearances were miles further than mine, that's how I don't quite understand how I could deck anything further, and how people can have11:1+ static CR with this same motor.
Ok- would be very interesting to know the specs of your current cam. Your cam is dictating the cranking compression and 200 is already at a high end of performance range for street use.

You can run a higher static compression of say 11:1 based on the type of cam used with it. Static compression by itself means nothing. The cam intake close event is what you need to know as that dicates what the actual operating compression of the motor will be as well as the cranking compression. For example, run 11:1 with a 41 intake close on pump gas and you'll have major issues. use a 59 intake close cam, you'll be good.

Read this and you'll get a very good understanding of cam dynamics- focus on the paragraphs that talk about corrected compression.
NRHS - High Performance for your Harley Twin Cam, Evolution, Sportster or Buell!

Then get your current cam specs, plus your new RS cam specs, and plug the numbers in at the compression calculator link I posted above. Knowledge is key- I'd hate to see you spend time / $ on swapping cams and doing piston mods only to not hit what you are hoping for.

Here's an excerpt from the above article on corrected compression and cam timing:

"The intake close timing is the most critical timing spec, in fact it's the most critical spec of the whole grind, it affects the rpm range of the cams more than all the other specs put together. It's also critical for understanding the appropriate compression ratio for the motor. Basically what's happening is that the motor has completed it's intake stroke, and started it's compression stroke, but we still have the valve hanging open. We don't actually start compressing the charge until we close that valve! So if you're closing it later, it stands to reason that you can run a higher compression ratio, because you're using less of the compression stroke to actually compress the charge. Likewise if you're closing the valve early you may want to run a lower compression ratio to avoid pinging because you're using more of the compression stroke to compress the charge. Hence the intake close point and the compression ratio you want to choose go hand in hand.

This is why the intake close event is actually the single most critical cam spec as it relates to the rpm range of the cams. It's always what you should look at first when you're trying to decide whether the cams you're looking at will put the power where you want it. It's importance is also the reason that advancing the cams tends to move the power down in rpm and retarding them tends to move it up in rpm. Even though the advancing the exhaust timing would try to move the powerband the opposite direction, the intake close event has the dominant effect.

Typical street cams are in the mid 40's range for intake close event. In the 50's is the hotter street cams and some of the race cams. In the 60's you find the race cams, some even get into the 70's. Below 40 degrees is where you find the high torque/stock compression type street cams
."
 
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