124" Project Storm Breaker

[Ohio HD]

spendy ?

Looks like it. $800 and up for a used one. I have the wooden box still as well. 

AMADA 36001112 DIGIPRO DIGITAL PROTRACTOR

[cheech]

Does the radius on the ball of your lifter plunger tool match the roller of a Harley lifter?
If not, max valve lift (on the tip/center of the lobe) I'd say would be a dead match, but anywhere "on the ramps" one would think there may be some variation, induce some error?

[Ohio HD]

cheech, I was going to say yes. But then you made me think, and I then remembered that we used 0.750" roller lifters in the small block Chevy's we were building. I opened a drawer of miscellaneous lifter parts that I have from old dead HD lifters. The HD roller is 0.700". So yes that can be causing some issues. It would also explain how the duration measures more than the spec as well.

cheech, you win the prize! I'm happy that you asked this. Learning has occurred.

Stay tuned.


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[kd]

Nice catch.  You may have to share some info with Jim (to explain your findings) once you get it sorted.

[Ohio HD]

cheech gets the credit for this one.

I already sent Jim an email telling him, and will report with new measurements.

[hrdtail78]

I have degreed a few cams inside the case.  My findings were about the same.  I talked with several builders in my circle about it at the time.  None were surprised and found the same.

Bottom line for me.  Things need to be put together, moved around, taken back apart and actual clearance needs to be verified.

[Ohio HD]

I have degreed a few cams inside the case.  My findings were about the same.  I talked with several builders in my circle about it at the time.  None were surprised and found the same.

Bottom line for me.  Things need to be put together, moved around, taken back apart and actual clearance needs to be verified.

That's a big yes.

 

[kd]

I have degreed a few cams inside the case.  My findings were about the same.  I talked with several builders in my circle about it at the time.  None were surprised and found the same.

Bottom line for me.  Things need to be put together, moved around, taken back apart and actual clearance needs to be verified.

That's a big yes.

 

    Actual verification is a real feel good experience. I remember some of the things we caught building strokers in the early 70's that saved us big problems.  That lesson stayed with me.  Assembling and disassembling is part of the route you have to take.  You just learn it's part of the process.   

[Ohio HD]

Well the larger roller does effect the readings a little. While I was checking Jim got back with me and said he's seen in the past when using a larger lifter roller (in his case on purpose) building a motor that you generally see a slight change in timing, but maybe not. He said it does effect the TDC lift. The purpose of the larger roller is to help accelerate the valve opening. I noticed that it also increased the duration based on the timing events I was getting.

So now the readings are much closer to what they should be. Only slightly off.


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[Ohio HD]

Cometic shipped the custom made SLS base gaskets two days after I placed the order, they arrived today, five business days from order date. These are SLS style, they have an 0.004" rubberized sheet on both sides, and then a stainless steel shim in between. So they will make an SLS base gasket in 0.030" thick, you just have to ask them specifically for that. 


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[kd]

My experience has been if they have the dimensional supplies (and the pattern) they will custom make any gasket in the size you want if they don't already have it listed.I think Ohio can confirm there's no extra fee.  That's a damn fine service from a company that already is a leading gasket maker.

[Ohio HD]

The charge was the same as for the 0.020" gaskets I bought earlier this year. Nice people to deal with too, and located in Ohio.

[Ohio HD]

I have new cam measurements. This is with a +2° keyway in the gear drive. The front cylinder is pretty well zeroed out, TDC lifts are really close to spec. The rear cylinder the values pretty much went the way the front measured without the offset keyway. TDC lifts are else very close. The tan columns are the new measurements.

The front cylinder is back to 10.1:1 corrected compression. The rear cylinder at 61° closing of the intake raises the corrected compression to 10.5:1. A little too high.

If I remove the +2° keyway I get front 9.9:1 corrected and rear 10.3:1 corrected.

Makes you wonder why we check head and base gaskets so carefully. Unless we measure what the cam is doing, we don't know anyway.


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[kd]

Makes you wonder why we check head and base gaskets so carefully. Unless we measure what the cam is doing, we don't know anyway.


Yes, that's where I was coming from earlier.  If your building something with tight tolerances you MUST check and confirm every step of the way.  If you don't and get lucky it may still also account for some builds that just don't hit the same mark that someone else did using the exact recipe at a similar altitude. Having 2 cylinders with one off 1/2 point of compression is not something I would care for.

[Ohio HD]

Well the truth is that this may be more common than what we know. CCP is a poor method of understanding if the cylinders are balanced. The difference can also be within the two gears on the cams as well. Or at least a stack up of multiple tolerances. Jim explained as did hrdtail78 that it's fairly common. Jim yesterday told me about an S&S setup with 640 cams that the readings were off about like mine are. He said the motor made the power it was expected to. He put something into perspective, he told me that these HD valve trains turn into wet spaghetti at high RPM. And I know he's right. Guys that are serious use setups built by companies like Jesel. Can you say $$$$

Remember gabbyduffy had issues with his S&S 640 cams being off by quite a bit as I remember.

[FXDBI]

Are the gears fixed on the cams or keyed and shrunk on?    Bob

[Ohio HD]

They're standard S&S gears, they use keyway and are pressed on. I put them on.

[FXDBI]

They're standard S&S gears, they use keyway and are pressed on. I put them on.

Thanks for that never played with gear drive on a Harley. Any chance you could make a custom key for one gear and make them the same?  Bob

[Ohio HD]

They're standard S&S gears, they use keyway and are pressed on. I put them on.

Thanks for that never played with gear drive on a Harley. Any chance you could make a custom key for one gear and make them the same?  Bob

You probably could. But you reduce the overall width of the key at the offset transition. Might be too weak. And they're only pressed on where as the the main cam gear to the crank gear is keyway, also a press fit, but also a grade eight fastener clamping it all together.

[kouack]

On my old evo softail the gear was spot welded to the cam, could be something to look at   

[Ohio HD]

The first rule in problem solving is look at all possible causes of the data you're getting. The compression calculator I have is making false calculation regarding corrected compression. The higher the compression the more it's exaggerated. I kept looking at the results, 2° in timing shouldn't cause that much variation. I went to the Those Dyno Guys site to use their calculator. I see a more believable change now, front cylinder intake closing at 63° ABDC gives 10.13:1 corrected compression. The rear cylinder intake closing at 61° ABDC gives 10.28:1 corrected compression. So I need to look into why my calculators results are skewed.

Front closing at 63° ABDC = 10.13:1
Rear closing at 61° ABDC = 10.28:1
Delta is only 1.46%

[Ohio HD]

This is also a very good compression tool from Hammer Performance. It shows a little different result, it reads slightly higher values. But it's because they aren't asking for the area above the top ring. Most don't know those values anyway unless you have the piston in your hand.

You can download their compression calculator here. It doesn't need to be installed, it runs as a stand alone program.

https://www.hammerperf.com/ttcompression.shtml