Cams and optimal engine configuration

[Donkey Hotey]

Yes, I have bought again. This time it’s 1940. This one is very different than my other five. I admit I didn’t test ride this one until trailering it 1,200 miles away.

When I finally got it out of Cody, Wyoming and grabbed a handful of throttle, I was immediately blown away at the power. It runs very clean and smooth down at 2,000 RPM and builds power all the way to redline. It’s doing this through the 3” K&N filter and stock mufflers.

I want to be clear: I’m not a guy who would want a cruiser with top end at the expense of low and midrange running. This engine is pure magic. This is what these engines should have been. Anyone who rode this side by side with a stocker would prefer this tune. It’s quiet. It’s smooth. It’s fast. There are no preferences to weigh in here: it’s better everywhere.

Now my question: how do we establish what was done to this bike and duplicate it? Does this sound strictly like H5 cams? I don’t know if it has them but it’s my only guess at this point. I have no personal experience with those cams so I don’t know. I can’t imagine ecu tune could make this big of a difference. Any other ideas?

[wytfut]

Nice!!

Sounds like H5s to me.
We put them in Blue. Night and day difference.
I'm not a true hot rodder either, but if I could find another set reasonably priced .... I'd do it.

Blue pulls hard all the way to red line.

I must admit though I've heard others with H5 cams saying they didn't notice much difference. After ours I can't figure out how/why...

Sounds like a good one Greg!!

[Donkey Hotey]

I wish I had known this years ago. In my opinion every one of them should be equipped this way. My first thoughts cruising around Cody was how smooth it was at low rpm. It just runs beautifully and pulls clean at very low rpm. My bikes have a range of tunes and I know they need to be updated to be sure they’re on the latest. I figured this just had one of the good tunes.

It wasn’t until maybe 20-30 miles later that I finally went to pass a car on Chief Joseph Scenic Byway that it caught me. I left plenty of room for the pass and knew altitude was also going to affect the power. I opened the throttle and the bike positively lunged forward. When I expected it to run out of steam, it kept pulling so I let it go. I was around that car like it was nothing, on a steep grade, at altitude. “WHAT THE HELL WAS THAT?!?” I blurted in my helmet.

I got into the throttle more on subsequent curves and I realized how different it was. This is how I would expect a four valve, double overhead cam engine to run. Just wow!

It also returned 45 MPG in the mountains and I wasn’t taking it easy. Like I said: pure magic.

Do you remember what Jim was selling the cams for back in the day?

[wytfut]

 Was trying to remember...
Believe it was 425$...   
Last set I saw sell this past winter on eBay (Jim must have found a spare pair laying around?)....  Went for I believe 1300$.

I wasn't paying as close to attention back in the day as I do now..

[Donkey Hotey]

Yeah, that set  last winter went for <cough> $1,525 <cough>. I remember because it matches the serial number of my first. They’re under two domes of bulletproof polycarbonate and displayed in my foyer for all visitors to marvel at.

They were obviously ground from E-H cast blanks. I suppose getting those blanks ain’t gonna happen again. I need to see if I have Jim’s email address...

[blackheart]

I can tell you the stock cams have very odd timing events.  I'm finally back to putting together my engine which this time is the "new" parted out #204.  I will mock up a degree wheel and post timing.  I recall the intake opens at a pathetically late time and closes late which might make one think it should have good top end but the opening point is so late one could almost advance it one tooth on the last driven gear.  I was comparing to my Victory stock cams and Vic Andrews V438 cams as well as some Vrod cams (Vrod obviously being a larger cam).

Total duration at 050 bucket lift was around 200, which is what you'd expect but had negative overlap.  I would like to play with moving the events but then the tune would have to change and I can't change it.

Andrews would grind any cam you want but they will be expensive.

[brixtonanimal]

This sounds incredible, i wish someone would manufacture these again

[blackheart]

I did get the 204 engine assy together and stuck into 307 bike.  At the end of the day upon alignment of the timing Mark's per what seems normal which results in perfect alignment of the marks between the top idler shaft mark and head casting mark I found the timing events very similar to the last time with intake c/l around 117 degrees and exhaust c/l around 97.  I advanced cam timing about 10 degrees and both cams are around 107.  I am surprised  but it seems to run great without acting lean at the bottom.  Does anyone know the H5 cams intended installed c/l and timing figures?  I will get mine tabulated and post.

Anyway it's good to ride it again.

[Donkey Hotey]

Sorry, I am fairly new to cam timing and notations. I understand measuring at 0.050" lift and all that. You said about 200 degrees of duration which is in crank degrees. The two centerline numbers you quoted of 117 and 97 are crankshaft degrees before and after TDC?

[franknsr]

This conversation has quickly escalated beyond my mental abilities when you guys start talking about c/i and degreeing, but my cave man mind caught the part about a need for uncut cams.

- Does anyone know if Swift still has raw components or have they all been scrapped?
- Any chance Dan Hanlon still has contact with the original casting house? His contacts have pulled us out of the fire before.

[wytfut]

It's been quite a while now since Swift has held any of our stuff. They got out once their custom motorcycle went defunct.
At the end unfortunately I had heard pallets had made their way to the scrapers.

As for cam blanks/sticks that would really cool if some more H5s came out. I'd buy a set.

[jimxt1338]

Blackheart,
Please let us know exactly how you advanced the cam timing and if you think it actually produces more power. I had considered this myself years ago but didn't want to screw anything up internally like smashing the valves. Are you thinking that advancing the cam timing might gain bottom end but loose top end horsepower?

[blackheart]

Yes, that is what I did.   Im sorry i've been busy and I travel but I intend to write down the factory timing then what I ended up with.  It sounds like a lot but I think by memory I advanced the cam timing in crankshaft degrees about 6 and this resulted in cam timing which was more like a cam "ground straight up" this statement from old school cam in block V8 days.

To your point this closed the intake earlier and should build a bit more bottom end at the expense of the top end.  I felt the top end was poor anyway so it couldn't get much worse.  I thought it should change the volumetric efficiency enough that the mapping in the ecm would need updated but it seems OK.  I am in engine breakin mode so I can't say if it resulted in a big power increase.  If I recall I advanced it one tooth on the lower idler to crank the retarded a tooth on the chain.  Visibly the timing marks at the head and upper chain driven gear were advanced where as before they were in perfect alignment.

[jimxt1338]

Blackheart...So I'm curious how this worked out? It has been almost a year since you changed the cam timing and was wondering if it improved performance or had any ill effects on the running of the bike? Can you give us an update?

[blackheart]

I know I'm behind in answering,  sorry about that as to how it was done. I did it by advancing the teeth but I never had it straight in my head exactly how I did it.  One tooth on the crank was too much in my opinion so I must have jumped one back on the chain, either up top or bottom.  Need to run the numbers to figure out how it caforging. This would give exactly the amount of change. I had a difficult time getting a thin enough dial indicator extension to reach the cam bucket.

Recall generally if cams are installed "straight up" the LCA of both intake and exhaust are the same.   Set to factory Mark's in two different engines I possess they are grossly retarded.  Readings I recorded at 0.020" valve lift for stock timing were IO = -10 BTDC, IC = 44.5 ABDC, EO = 25 BBDC, EV = 10 BTDC.  Thus both profiles exhibit 215 deg @ 0.020" valve lift.  IC = 117.5, EC = 97.5.  Reset my cams are roughly 112 IC & 108 EC which is still retarded 2 deg.  But that's better than 10 deg.  I'd liked to have it installed advanced but I felt then I was guaranteed to have mapping issues which I cannot change myself. 

Short story your concerns with piston to valve interference are not warranted as these are very mild profiles.  I didn't even bother checking.  I have ridden this engine for 3000 miles and it runs very well, having a very slight hesitation sometimes just off idle.  I think it has better power. I'm still running stock air filter, altered exhaust.  Examinator indicates tune is pretty consistent and Rich, I recall around 750 mv most of the time. Has AEH tune. Mileage is okay I get about 175 miles on a tank but that's in error by roughly 10% usually get 4.5 gallon in it. Mid 30 mpg. Not great but keeps the heads from loosening seats and cracking casting.

I can tell you that when I was at factory Mark's the Mark's at cam idler and head were perfectly lined up.  Altered timing I was advanced on cam timing. 

If I did it again I would Redowel the cam/gear and make them straight up or slightly advanced then all the gear & chain Mark's are on the money for less confusion for the next man.

I still need to see if I can save the #307 cases and crank, perhaps I can put it together again and do the above along with seeing if the Northstar V8 piston could work for us as a high quality hypereutectic in lieu of the 2618 custom forgings.