FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: jayb on February 25, 2019, 05:16:13 PM
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This engine came to me by way of Tim Meyer, who was going to rebuild it for this customer but lost his engine building guy, so the customer contacted me. Tim's shop is in Fairmont MN, so on one of my trips his way I picked it up. The engine had been assembled by the customer but never run, because there had been some issues on assembly. It was completely torn down when I got it, so I went through it from the ground up. I found lots of little problems that could have spelled disaster, which I will detail below, but in the end the engine went together and ran fine today on the dyno.
I will post the dyno results tomorrow night (Tuesday 2/25/19). In the meantime, feel free to guess the HP and torque, on both 110 octane race fuel and 91 octane pump premium with 10% ethanol; I ran it both ways. Also, you can try to guess the average vacuum at 850 RPM idle with this setup.
The engine is a 0.030" over C scratch 428 block with 428 rods, ARP bolts, and Probe forged pistons, with the normal 5/32" moly top ring, cast second, and 3/16" oil ring package. When I got the engine Tim Meyer told me that there was a question about main and rod bearing clearances being too tight, so I checked them and sure enough, they were WAY too tight, as low as 0.0008" on the rods and just over 0.001" on the mains. I took the crank in to have it touch-up ground, and then the clearances came in at .0018" to .0025" on the mains and rods. When assembling the short block I decided that I'd better pull the rings off the pistons (they had already been installed) and check the end gaps. When I pulled the rings off I found that all the top rings had been installed in the second ring groove, and vice versa! Could have been a minor issue ::) After correcting that the short block went together uneventfully. However, I also noticed that the frost plugs were the 1-3/4" ones, so I got some 1-49/64" frost plugs and installed those instead. I had previously opened up the oiling passage from the pump to the oil filter adapter, and tapped all the press-in plugs for screw-in pipe plugs, so I think the short block is pretty solid.
The heads are bone stock Edelbrocks. I measured the chamber volume at 73cc, and with the 4cc eyebrow in the pistons, static compression ratio calculated out to 10.9:1. The customer had bought the whole Edelbrock performance package except for the intake, so he had the Performer RPM cam and lifters. But he wanted to run power brakes, and my own experience with the Performer RPM cam was that it had very limited vacuum, so I suggested a cam change. We decided on a single pattern hydraulic roller stick, Comp Cams lobe 3613, which has advertised duration of 282, duration at 0.050" of 230, and 0.555" lift. The lobes are on 110 degree centerlines, and the cam is installed 4 degrees advanced (106 ICL).
I installed and degreed the cam and the timing set, and then installed the front cover and stock balancer, but discovered a problem with the windage tray. It looks like it was one of those cheap ebay things, and when it was installed the rod nuts would hit the tray on the way around. Turned out that the louvers in the windage tray were punched out wrong, and were actually facing in towards the crank, rather than out towards the oil pan. I would theorize that they put the sheet that makes up the windage tray in the louver press first, then bend it in a different fixture, and whoever did this probably put the sheet into the bending fixture upside down. Anyway, after some creative work with a ball peen hammer I was able to get the louvers bent down into the correct position, and then the oil pan went on without any drama. By the way, this engine uses a high volume oil pump and a stock pump drive, plus a Milodon pan and pickup. Oil capacity is just about 7 quarts.
In addition to the new cam we also sprung for some Morel hydraulic roller lifters. Pushrods were 5/16" Smith Brothers, and we replaced the Edelbrock spring package with Comp beehive 26120 springs, in an effort to get this engine to rev a little higher than most hydraulic cam engines. The rockers were a Harlan Sharp setup, with their end stands and shafts.
For an intake we used an Edelbrock Streetmaster, and I port matched the manifold to the heads, and opened up the plenum per the usual process on these intakes. The carb is an 800 double pumper rebuilt by Holley, sitting on a 1/2" four hole spacer. Headers are Hooker Super Comps for a Mustang, with 1-3/4" primaries and 3" collectors. Ignition is handled by a Mallory Unilite distributor and some kind of a chrome coil, fired through the MSD Digital 6 on my dyno.
So, to recap:
- .030 over 428 block
- 10.9:1 forged pistons, standard ring package
- Stock Edelbrock heads
- Comp hydraulic roller cam, 282/282, 230/230 @ 0.050", 0.555" lift, 110 LSA, 106 ICL
- Port matched Streetmaster intake
- Holley 800 double pumper carb, 1/2" 4 hole spacer
- Hooker Super Comp headers, 1-3/4" primaries, 3" collector
I also experimented with a 1" Super Sucker on the dyno, and will report the results from the best pulls, regardless of the spacer, on pump gas and race gas. A picture of the engine on the dyno is below. Any questions on the combination, let me know, and good luck with your guess!
(http://fepower.net/Photos/Posts/JT428.jpg)
Edit: Forgot to add, I will be reporting corrected numbers. It was very cold in Minnesota today, and the barometric pressure is high. The very unusual result of these weather conditions is that the corrected horsepower and torque is actually LESS than the raw power values. This is a function of the high pressure and very cool air that the engine is breathing. Correction factor for most of the pulls was 0.996 or so.
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447 hp @ 486 tq.
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465 hp, 478 tq.
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110 race gas has 474hp at5750 and 490tq at 3750 and 91 pump gas has 466hp at5750 485tq at 3750 vac av is at 9
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462 hp 487 tq
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93 octane 432 Torque 474
110 octane 443 Torque 485
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449 hp, 475 tq
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Since you said nothing about peak numbers, I'll guess zero horsepower and zero torque at 9000 rpm. To prove me wrong, you must take the engine to that level.
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435 hp-475 tq on 91 pump gas
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436 on pump gas
Average vacuum 14”
JB
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465 HP on 110.
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468 HP on 93, 451 o 110, 15" vacumn
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485 hp at 5200. 530 tq around 3500.
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485 tq 3800, 477 hp 5400 Joe-JDC
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480 hp @ 5500
500 tq @ 3300
14" vacuum
Don't think the fuel will matter much.
Wait, what do we win? Do we get a choice?
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470 hp and 525 torque on 110.
465 hp and 520 torque on 91.
My limited experience says that using high octane fuel in a relatively low compression engine can lead to the optimum total ignition timing being very high. I am curious if you kept adding timing until the power fell off with the 110 gas?
Sounds like a really good combo that will be super torquey and fun to drive, assuming the octane is high enough for an aggressive timing curve.
JMO,
paulie
edit: Oh yeah, I have no idea on idle vacuum. 12"?
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Nice low maint: car cruise engine definitely and 10.9 cr will give it some pop. That intake, thinking helps add to a fairly flat torque curve. Not real sure it needs that much carb, 750 should work well.
say:
441hp at 5500 = 462tq at 3450 on 93 octane
456hp at 5550 = 489tq at 3550 on 110 octane
230 @ .050 maybe 14in
Thru rpms in to test myself. I learn so much how parts interact from these games. hahaha
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481 TQ @ 3950
447 HP @ 5250
Both on 91
Idle Vacuum at 12.5
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So what's the prize, Jay? A free Cammer?
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You're dreamin' buddy ;D The prize is the FElony's admiration and respect ;D ;D
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Put me in for 2 of those Jay. ;) :o 8). Just playin.
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You're dreamin' buddy ;D The prize is the FElony's admiration and respect ;D ;D
Oh. In that case, 1268 hp, 850 lb-ft.
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You're dreamin' buddy ;D The prize is the FElony's admiration and respect ;D ;D
The joke here is you thinking I have any of the traits possessed by you puny earthlings.
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91 octane 415 hp 460 tq
110 octane 425 hp 475 tq
11.5 inches vacuum
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500 HP @ 5200
475 TQ @ 3500
12" vacuum
On pump gas. Don't care about race gas results.
If some two bit magazine can get 500 HP from a 390 with Edelbrock stuff (back when the heads were introduced), then I'm not understanding all the low-ball guesses.
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465hp @ 5400
500ftlbs @ 4000
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You're dreamin' buddy ;D The prize is the FElony's admiration and respect ;D ;D
Oh. In that case, 1268 hp, 850 lb-ft.
LMAO!! I really wish I hadn't taken a drink before reading that!
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You're dreamin' buddy ;D The prize is the FElony's admiration and respect ;D ;D
Oh. In that case, 1268 hp, 850 lb-ft.
LMAO!! I really wish I hadn't taken a drink before reading that!
Likewise. I gotta admit, someone who takes that extra step to sidestep me is damn realistic. And reputable. Even if it means losing access to mountains of Cleveland parts I have no use for. No biggie. ;D ;D ;D
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And here are the results:
Race Gas: 505.8 lb-ft @ 4100 RPM, 455.4 HP @ 5200 RPM
91 Octane, 10% Ethanol Pump Gas: 507.2 lb-ft @ 3700 RPM, 444.2 HP @ 5000 RPM
Manifold vacuum at 850 RPM averaged 11.5 inches, which should be sufficient for power brakes.
I was very pleased with the performance of this engine, especially the torque. I ran some of the first tests down at 2500 RPM, and even there it was making over 400 lb-ft. It has a really nice, wide torque band, and should make a great street motor.
Best race gas results were obtained with the 1" Super Sucker installed, and 34 degrees total timing. The Super Sucker didn't provide a big advantage though, less than 1 HP on average. The timing was increased in 2 degree increments from 30 degrees up to 36 degrees during the tests. No change was observed between 34 and 36 degrees, so the timing was backed down to 34 degrees for most of the race gas testing. Jetting for the 800 Holley settled at 71s in the primary, and 81s in the secondary.
Best pump gas results were obtained with the 4 hole spacer, but due to the insignificant difference with the Super Sucker on race gas, the Super Sucker was not tested with the pump gas setup. Timing was again optimized for the pump gas setup, and this time 32 degrees total turned out to be optimum. Jetting remained the same as for pump gas, and the engine ran a bit leaner on A/F, but still in the 12.5:1 to 13:1 range.
Here are the two dyno plots for the best race gas and pump gas pulls:
(http://fepower.net/Photos/Posts/JT12.JPG)
(http://fepower.net/Photos/Posts/JT15.JPG)
Also, here is the Super Sucker vs. 4 Hole spacer on race gas:
(http://fepower.net/Photos/Posts/SSvs4H.JPG)
I had installed beehive springs on this engine in the hopes of improving the RPM range of the hydraulic roller lifters. It didn't seem to have too much of an effect at first, and early on I saw the typical hydraulic lifter tipover at around 5300 RPM on this engine; the graph below shows one pull where it was quite pronounced. The green tangent lines added to the graph show the discontinuity in power output that is typical of this issue:
(http://fepower.net/Photos/Posts/RPM Band.JPG)
What I noticed, though, was that as the oil temperature continued to increase during the dyno session, this issue became less pronounced. You can't really see it too much in the best race gas pull, and the it seems to be altogether absent except for possibly the last data point on the best pump gas pull. By this time the oil temp had gone past 200 degrees. I was running Valvoline VR1 10W-30 in this engine, and had the lifter preload adjusted per Morel's specifications, so I don't think there was much more that could be done. Me, I'm sticking with solids ;D
Since I dynoed this engine alone I was not able to take a video of it running on the stand. However, the dyno software has a playback mode, so I took a video of my computer screen on a playback of the race gas pull and posted it on you tube at the link below.
https://youtu.be/s-eTZWzRNmo
By the way, this video has been on my you tube channel for the last 24 hours. One of you could have looked there, and nailed the answer LOL!
As mentioned in my first post, there was nearly a zero weather correction for this engine, due to the 45 degree air entering the engine and the relatively high barometer, and low humidity. Raw HP and torque numbers were 509.8 and 458.8 on race gas, and 511.0 and 447.5 on pump gas. You don't see the raw numbers higher than the corrected numbers very often...
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Looks like fastf67 wins the HP prize, and cjshaker wins the torque prize. Chilly also guessed 500 for torque, and was really close on the RPM, but cjshaker guessed 500 first, so I had to give it to him. Great job, guys! You may collect your accolades from FElony. :o
Also, FElony wins the Out-Of-Bounds prize, and Lykins wins the Hopelessly Optimistic prize. ???
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OK, fastf67 and Dougie. You guys are the shizznit. Your guesses are not guesses, they are the epitome of careful, logical, wondrous mental calculations. The rest of humanity would be so much more tuned and ethereal if only they could achieve a fraction of your talent and modesty. Personally, I stand in awe. Or, I would stand if only my entire blood reservoir wasn't 80 proof right now. Neverthelesssss, the rest of America is beholden unto you.
I would really like to hear an FE at 9 grand, but it ain't to be seen in anybody's lifetime.
And, if Jay actually had t-shirts, he wouldn't have to rely on me to supply accolades. Get with the proggy, froggy.
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And let's have a meaningful discussion about the two torque curves. We all know that hp ain't jack; it's tq that moves the car.
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The only thing that sorta surprised me is the 400 rpm difference in torque peak between race and premium fuel, with premium winning at +2 @ 400 rpm lower. I guess the slightly slower burn rate couldn't compete at that low of an rpm on what is basically a pump fuel street engine, even with advanced timing?
FElony, Shady and I have been very close on almost every guess. Him and Harley Jack almost nailed the HP guess. I don't know about Shady, but I have a pretty simple rule I follow. Seems to work pretty good most of the time.
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Jay, which beehives and retainers did you use and at what installed height?
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Comp 26120 springs and the matching steel retainers, setup up at 1.88" installed height. They measured just about as specified for seat pressure, 150-155 pounds.
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I would think that the 230* camshaft duration @ .050" might be the reason the engine noses over instead of lifter issues. That is a lot of seat pressure for only 5300 rpm or so. Still, great information, and glad you posted it for us. Joe-JDC
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I think that hyd setup did exactly what it should have done. A .030” over 428 with unported edelbrock heads and a short duration cam with no duration split won’t be a high rpm engine.
I’ve done several 428CJs here with similar specs (but more exhaust duration) and about 5500 is about all they can do.
Spring pressures are fine for 5500, and the dyno sheets didn’t show any valve float, it just simply ran out of camshaft. I think if you would have had more duration though, the lobe design would have needed to be different or it would certainly not have lived up to expectation. Those Xtreme Energy lobes are not easy on stuff.
Ok, so I was a little off on my guess......
I do think with some more tuning that the engine vacuum could be improved upon. 11 inches seems low for 62 deg of overlap.
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Very nice torque #s. I knew it would come in pretty quick and hold awhile, but not expecting to see it hit 500+. That will hold you in your seat with a smile.
P.S.
Your tire dealer will love you. Lol
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Interesting. My Eboks like 36-37 degrees total timing on high octane pump gas.
Nice engine!
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I think that hyd setup did exactly what it should have done. A .030” over 428 with unported edelbrock heads and a short duration cam with no duration split won’t be a high rpm engine.
I’ve done several 428CJs here with similar specs (but more exhaust duration) and about 5500 is about all they can do.
Spring pressures are fine for 5500, and the dyno sheets didn’t show any valve float, it just simply ran out of camshaft. I think if you would have had more duration though, the lobe design would have needed to be different or it would certainly not have lived up to expectation. Those Xtreme Energy lobes are not easy on stuff.
Ok, so I was a little off on my guess......
I do think with some more tuning that the engine vacuum could be improved upon. 11 inches seems low for 62 deg of overlap.
I don't agree that the dyno sheets didn't show any valve float, the early ones certainly did. The one graph I showed with the green tangent lines on it show a clear discontinuity in the horsepower curve. I've dynoed enough engines to know that isn't normal; a discontinuity like that is a dead giveaway to valvetrain issues. However, the issue seemed to go away as the oil temp rose and the dyno session went on. Also, I do agree that the peak HP RPM was about where it should be; any valvetrain issue in the early pulls didn't really affect peak HP production. What surprised me the most was the high RPM where the engine made peak torque on race gas; I was figuring 3600-3700 RPM for the peak torque value, and that's where it landed on the pump fuel, but the race gas was higher. Go figure...
Brent, I'm curious about how you think idle vacuum can be improved. Are you suggesting different carb tuning? The idle vacuum seemed pretty much in line with what I was expecting, but if there's something I could do to make it better, I'd give it a try.
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What surprised me the most was the high RPM where the engine made peak torque on race gas; I was figuring 3600-3700 RPM for the peak torque value, and that's where it landed on the pump fuel, but the race gas was higher. Go figure...
I mentioned that in my post. If I recall correctly, doesn't race gas have a slightly slower burn rate? That would probably affect torque output, especially at lower rpms. You'd think that the advanced timing might overcome that, and this is just a guess, but I think it just wasn't optimal for the engines operating parameters. The faster burn rate and retarded timing just seemed to be the optimal point for the engine. Knowing that, if I was going to race it, I'd probably just run premium with the backed off timing (also safer), and maybe just toss a gallon or 2 of race gas in if I were worried about detonation.
All the above are just guesses though.
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FElony, Shady and I have been very close on almost every guess. Him and Harley Jack almost nailed the HP guess. I don't know about Shady, but I have a pretty simple rule I follow. Seems to work pretty good most of the time.
Well, I figure what I think the engine should do & then I take 10% off for being overly optimistic.
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I usually see loss of valvetrain control (or float) as an up/down in hp within several hundred rpm. I'll have to go back and look at your charts, but it looks like it was just done and just fell off. This one is in that black/white area of not being able to really see what the real underlying issue is.....if it's done without valvetrain control issues, then the cam was too short. If it was done because of valvetrain control issues, then it was an aggressive lobe coupled with heavy valves.
I will say this, if the cam had been made to the numbers in the lobe catalog, I think it for sure would have been easier on things. I typically try to aim for around 55° major intensity (delta between advertised and .006" duration on a hydraulic cam) because I've found that to be a sweet spot in terms of noise, power, and ability to rpm. I think those Xtreme Energy lobes are nice for SBF's/SBC's with 11/32" stemmed 2.02/1.6 valves and polylock adjusters, but once you introduce a big FE valve and a rocker arm with the adjuster hanging off the hindend, the weight combined with the lobe aggression start to be too much.
Those Comp beehive springs setup as advertised (155-160 seat, 385-390 open) will let an FE hang on to 6500 with non-adjustable rockers, 11/32" stemmed 2.150/1.625 valves, and the correct lobes.
As for tuning, what did you have the initial timing set at? I'd be tempted to try it at 18-20 initial and then try to close the butterflies a little more for increased vacuum. I was pretty shocked to see only 11" of vacuum with that little cam.
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Jay, your graph from this dyno is what I generally associate with valve float:
http://fepower.net/simplemachinesforum/index.php?topic=2675.0
The horsepower starts to go up, then dip, then come back up.
Now, it could be that the lifters were giving up and not able to hold the valve spring pressure, but I only see that on aggressive cam lobes and it's audible on the dyno. The last time I heard it was with a 230/236 Xtreme Energy cam that the customer supplied, in combination with 3/8" stem 2.09/1.65" valves and Comp Cams lifters.
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Jay, are the timestamps on the dyno sheets when you did a snapshot, or when the pull was?
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The time stamps are when I created and copied the charts, not when the pull was.
Brent, if you've got a copy of my book, look on page 228 to see an example of a solid vs. a hydraulic in a similar engine to the 428 in this thread. The hydraulic cam HP trace looks just like the one from this engine with the green lines drawn in, even tips over at the same engine speed. If you don't have a copy of my book, you should ;D ;D
I have seen traces like the one you posted too, but those curves were on a solid lifter engine, not a hydraulic lifter engine. Also based on your comments I don't think any loss of valvetrain control was due to the springs. I think what is happening at the higher engine speeds is that the lifters are pumping up, and holding the intake valves off the seats when the lifter is on the heel of the cam, resulting in the power loss. With hotter oil, the lifters can bleed down faster, and the problem starts to go away. Also thinner oil; the problem would have been worse with 10W40, but may have been better with 5W20.
On the timing, there was 24 degrees built into the Unilite distributor, and I had no way of changing that without also changing total timing. I always tune for total timing on the dyno, to protect the engine at high speeds. Based on the 24 degrees in the distributor, the engine probably only had 8-10 degrees of initial. It makes sense that vacuum would improve with more initial timing, and I will suggest a distributor mod to the owner of the engine. If he had 18 degrees in the distributor the initial would be 14-16, and I'll bet that you are correct that it would improve the vacuum.
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Jay, I've used those very lifters up to 6500 rpm, with 10W30 and usually colder oil temps, with spring pressures up to 400 lbs open, and preload set at .060". I really don't think yours were pumping up. IMO, it was the cam giving out, or it was a combination of aggressive lobe with heavy valvetrain.
Here's a dyno sheet of the 390 with TFS heads. It used pretty much the same parts that you have, including the same beehive springs, standard Morel lifters, 10W30 oil, and pretty cold oil. Cam lobes were lazier than yours and used 2.190/1.625, 11/32" valves. We pulled it to 6500 and as you can see, it had only lost 1 hp between 6250 and 6500 rpm.
(https://farm2.staticflickr.com/1853/30878468088_3d69a962f6_z.jpg)
Please know that I'm not being argumentative, I'm just trying to put a finger on exactly what was causing the drop off.
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I'm not trying to be argumentative either, and I think you hit the nail on the head with the cam lobe. If this is a rather aggressive lobe, maybe it is causing the lifters to pump up, when the oil is thicker. You have more experience with these lifters than I do, but its pretty clear that something is going on, and its not the springs. So, combination of the lobe and the hydraulic lifters, and oil temps below 200? That discontinuity in the HP curve is caused by something...
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Jay, if you think it’s got float throw a set of .050 keepers in there and see what happens. It will raise pressure by 18 lbs or so and you are still a mile from coil bind with that cam. If it is valvetrain related it should move up little before it loses control.
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I don't think its valve float, Ross, I think the lifters are pumping up and leaving the valves open by some small amount, so the combustion chamber isn't perfectly sealed when the spark plug fires, causing the power loss. Hotter oil is thinner, and the pressure is down, so that improves the lifter pump-up situation. A more radical cam lobe makes it worse, because the closing ramp is faster, and would make it easier for the lifter to accept more oil and pump up while the valve was closing. Just a theory of course, but my observations on this engine were an observed discontinuity in the power curve around 5300 RPM until the oil temperature got to over 200 degrees, and Brent's confidence in the valvesprings being capable of running to 6500 RPM with the right combination of parts. If the issue is not the valvesprings, and is dependent on oil temperature, can you think of another explanation?
The test I thought about running is to put zero pre-load on the lifters and see if that changes the power curve when the oil is cold. If that eliminates the discontinuity in the power curve, then I think it has to be a lifter issue. But if it doesn't, that also doesn't necessarily mean its NOT a lifter issue. Regardless, its not my engine to play games with, so I'm not going to run that test. Maybe next time...
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Well Brent knows how to make those Morels work, I would follow his lead. One question I have is on the lobe, is it 288 adv or 282? The lobe number is 288 at .006 in the catalog, but lift didn’t seem to match up to anything with a 1.76 or 1.73 ratio either.
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Looks like valvetrain control issues to me. The term "float" is something of a misnomer - - its more a matter of the combination of spring, cam, rocker, and valve weight simply being "unhappy". I have had reasonably comparable packages RPM nicely beyond 6000, and others do what happened here. The sharp nose over is a key indicator.
The lifters do not really "pump up" all the time. Sometimes they are collapsing. Not collapsing under spring loads, but collapsing because the oil has become aerated and thus compressible, unlike the solid fluid that should be filling them. Different oil can help, different amounts of oil in the pan or various windage trays or deeper pans can help. Sometimes you can make it much better by adjusting the lifter deep into it's travel - just off the bottom - which shortens the collapsible column within.
We normally crutch the problem with more spring because that is how we've been trained forever, and we use lighter weight parts because we "know" that it works most of the time. Lacking a Spintron and a ton of development time sometimes the best thing to do is just try things - I have swapped springs and retainers on the fly just to see what happens. Sometimes it gets way better. Sometimes it does pretty much nothing. Sometimes adding or removing a quart of oil makes a surprising difference - especially if you see pressure wiggle at the top of a pull RPM range. And if you are running a rear sump shallow pan to clear a rack & pinion you will need to simply accept the fact that your oiling system is marginalized by the pan's proximity to the center of the crank.
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Well Brent knows how to make those Morels work, I would follow his lead. One question I have is on the lobe, is it 288 adv or 282? The lobe number is 288 at .006 in the catalog, but lift didn’t seem to match up to anything with a 1.76 or 1.73 ratio either.
The catalog says 288, but the cam card says 282. Seems like just an out and out error in the catalog. Lift says .555 on the cam card, catalog lists it at .544 at 1.7:1; with a 1.73:1 FE non-adjustable rocker, that is pretty close to .555.
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Jay, do you have oil pressure data from an early and late pull?
If the engine isn't gone, it may be easy to try some oil-related activities, as well as some preload adjustments. I may be willing to work a deal on some other "adjustments" as well, for R&D purposes.
I'm trying to find the dyno sheets from one particular 428CJ engine to see what it did at higher rpm. It was basically a box-stock 428CJ with unported heads and just some good pistons and a hydraulic roller camshaft. If I remember correctly, it made 425 hp @ 5500, but I'm trying to find the sheet to see what it did above that rpm.
If it's not the camshaft nosing over because it's done, I think it almost has to be the lobe aggression. I have tried 10 different hydraulic roller lobes from Comp (and a handfull from Crane and Bullet) in FE's and I have it narrowed down to about 3 that work and work very well. What's interesting is that I can get away with a hair more aggressive lobes in my Windsor and Cleveland stuff and I attribute that to the smaller/lighter valves and polylock rockers.
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The only thing that sorta surprised me is the 400 rpm difference in torque peak between race and premium fuel, with premium winning at +2 @ 400 rpm lower. I guess the slightly slower burn rate couldn't compete at that low of an rpm on what is basically a pump fuel street engine, even with advanced timing?
Octane is resistance to spontaneous combustion. Burn rate is independent of octane. Its a different characteristic. Its the difference between how hard it is to start the fire and how long it takes the wood to burn. We do not have burn rate information. In reality race gas will often be designed burn more quickly than pump gas - its optimized for high RPM where we do not have much time in each cycle. We could also be looking at energy output variances between the fuels - pump gas may well have alcohol & oxygenators in it that will impact the amount of energy available from a complete burn.
That stated, the 4100 RPM data point almost looks like an anomaly - did that little spike repeat in subsequent pulls?
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Here's a 511 cube engine with a set of Barry's CNC heads and a Comp hydraulic roller, 251/257 @ .050". Comp beehives, 165/390 on spring pressures. Morel lifters.
(https://farm8.staticflickr.com/7869/32294836887_ef610d0179_z.jpg)
Here's a 445 with Barry's heads and a Comp hydraulic roller, 235/241 @ .050", with Comp 930 valve springs, 145/360, Morel lifters.
(https://farm8.staticflickr.com/7855/40271908133_0ac66cb21b_z.jpg)
And here's the 428CJ with the same Morel lifters, Comp hydraulic roller, 227/233 @ .050", with Comp 914 springs, 150/360. It had Ferrea 3/8" stem 2.09/1.65 valves. As you can see, it made it to 5500, but dropped off quite a bit at the end. Considering this engine used the same lobes that I use in a lot of my engines, same lifters, and same valve spring pressures, it's either the heavier valves that made it drop off, or it was just the head/cam combination.
(https://farm8.staticflickr.com/7860/47236921771_d7bda62ac5_z.jpg)
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Well Brent knows how to make those Morels work, I would follow his lead. One question I have is on the lobe, is it 288 adv or 282? The lobe number is 288 at .006 in the catalog, but lift didn’t seem to match up to anything with a 1.76 or 1.73 ratio either.
The catalog says 288, but the cam card says 282. Seems like just an out and out error in the catalog. Lift says .555 on the cam card, catalog lists it at .544 at 1.7:1; with a 1.73:1 FE non-adjustable rocker, that is pretty close to .555.
Well, let me first say I am not critiquing the motor, because other than a little wiggle at the peak of where I would expect from the cam anyway and maybe some timing curve work, it's a nice engine on a budget
Interesting on the cam lobe catalog vs cam card, LOTS of errors in the lobe catalog. Incredible errors in some cases that force you to do the math yourself all over the document. Did you get a chance to measure what the cam really was? Needless to say if it was 282 it was more aggressive and with your rockers you had more lift, which compounded valve control
I think whoever told you the cam lobe got it right, I think it was Brent. IMHO it's not a hydraulic lifter issue per se, it's likely the lobe. If you compared the intensity measurements of your lobe 12.7 opening/13.2 closing with a Thumpr lobe, 14.7/15.0 you can see the valve is opening a lot quicker and closing a lot faster. I don't think your opening rate is lofting, but your closing could be bouncing, or you could be having a little oscillation being so far from bind.
The oscillation and bind comment is half opinion and half experience....I just checked coil bind on a set of those and they are mismarked on the box, they are about 1.19-1.20 coil bind, so you can do the math on your clearance, what is opinion is: that setting up to close to bind matters on a beehive...if it was a regular spring I'd say yes, but I don't have the experience of running beehives to say it matters like it would a regular spring
I do still think that what you have can be crutched on your engine with pressure though using Barry's terms. There is "enough" spring pressure by most standards, sure, but heavy components, more aggressive cam, both add to the challenge and adding a little more seat and open should force the lifter to stay put a little longer up until the point it can't operate like a hydraulic lifter anymore. It also moves the spring around if oscillation is an issue
Although ignition may not matter on the dyno, I still think a set of .050 keepers and a distributor recurve would be worth it to see how idle vacuum and power changes with a cheap action. If you don't have a Mallory "key" I can post the measurements, they are very easily adjustable.
I am of course being selfish because I am trying to figure out reference points for my 461 CJ build that needs RPM and vacuum, and what you learn I will proudly pirate!
Last comment....the race fuel discussion to me could result in anything depending on the fuel, and even the pump gas has a wide range now. To me, it clearly has different characteristics, but remember, change the brand, change the line within a brand, and characteristics change again. It is cool to show that fuels do change behavior though and race fuel isn't always better
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I dont know anything about gas but I had a Triumph Boneville in the
early 80s 11-1 comp some cam, dont remember. Run fine on pumpgas
whatever the highest rating we had then 99 i think. One time i was out of
fuel and we filled a couple of litres race gas just to get me home that night
it was running rough on that, i could feel it in my whole body (solid mounted engine)
Almost like when the carbs was out of sync, and would not idle, considerly down o power.
Went away next day when i filled up on pumpgas ???
And one time with the Model -A, i filled up at a small gasstation with a local gasbrand
first thing i noticed was the smell of the gas, just like the gas you can buy for chainsaws
and lawnmower that suposed to leave healtier exhaust it smells like the gas smelled when i was a kid
next thing it started to snease throught the carb so i fattened the mixture, You just turn the choke knob
to adjust the mixture. And holly plugwires Batman, it picked up so much power and was running
so smoth on that gas increased the topspeed by almost 10 mph it was incredible. But it wanted a fatter mixture.
When you have 40 horses to begin with i guess you notice every horse gained
My dad bought a new Stihl chainsaw filled it up with that Aspen healtgas after one tank it would not run anny more
so he went to the guy who sold it. He said you have used Aspen gas right? Yes.. Thats the problem it is crap
he dumped the gas filled it with regular gas, fourth pull it started ??? and have run since on regular gas
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And if you are running a rear sump shallow pan to clear a rack & pinion you will need to simply accept the fact that your oiling system is marginalized by the pan's proximity to the center of the crank.
I saw one of those Canton pans at the swap meet two weeks ago. My goodness that shallow flat area is much larger than in needs to be! Just a simple half round notch right where the rack is and the keeping the rest deeper would probably help a whole lot.