FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: scott foxwell on July 09, 2017, 02:51:03 PM
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This was the last FE I did several years ago. Just posting this for entertainment. The engine didn't last long with the Eagle cast crank. With a valve train upgrade to T&D's and a couple more dyno sessions and some tuning we think netted close to 700 at the crank. The owner just loved to rpm the thing and it didn't take long to break that crank.
Here's a link to the build thread:
http://www.performanceboats.com/gn7-dyno/70625-446ci-ford-fe-build.html
(http://www.performanceboats.com/gallery/data/500/medium/0319.JPG)
(http://www.performanceboats.com/gallery/data/500/medium/0353.JPG)
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279@.050 on a 446 build?
Dang...
Write says an Eagle crank BTW
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Just starting to say that would be the first Scat crank failure I have heard about. Eagle, yes. Joe-JDC
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Yeah, my bad. Should have gone back and re-read to freshen the memory. It was an Eagle cast crank.
I'll edit to correct. :o
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Scott, after reading about your build I thought you might be interested in the following technical service bulletin from Ford, from back in 1965. This is related to the misalignment between the oil hole in the bearing and the block. It turns out that the cam bearings are on different centers than the crank bearings, leading to this misalignment. Ford addressed the issue in the service bulletin, and basically said its OK as is. Most high performance engine builders don't agree, of course. However, something to consider is that two bolt FE blocks tend to develop cracks along the oil passage between the mains and the cam in positions 2 and 4, when pushed to higher horsepower levels. Therefore, some builders don't want to grind any material away from the main saddle, and instead will oval the oil hole in the bearing to get better alignment with the oil passage.
(http://fepower.net/Photos/Posts/oil hole align.jpg)
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Yeah, that was the first flag that I saw...
The second flag was that it only peaked at 5500 (come on, really????!!!) and flatlined until 6500......with a 279/290 @ .050" camshaft....WAY too much camshaft for the cylinder heads.
Third flag was the use of solid roller spring pressures with traditional rocker stand mounting studs. After you see fretting under the stands, or even worse, pull one or two of the stud helicoils out, you switch to T&D race rockers (not street)...
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Yeah, that was the first flag that I saw...
The second flag was that it only peaked at 5500 (come on, really????!!!) and flatlined until 6500......with a 279/290 @ .050" camshaft....WAY too much camshaft for the cylinder heads.
Third flag was the use of solid roller spring pressures with traditional rocker stand mounting studs. After you see fretting under the stands, or even worse, pull one or two of the stud helicoils out, you switch to T&D race rockers (not street)...
Thanks Jay...I read that service bulletin. I don't feel that grinding a radius at the edge of the oil hole weakened anything. It's a nice radius, no stress riser and didn't remove enough material to cause an added problem or worsen existing problems. I thought about doing it to the bearing but didn't want to move the oil hole off center of the bearing. My choice on that one. No way I was leaving it "as is" for this sort of performance build. You can also see I was pretty careful to make a scribe line at the edge of the groove and only remove enough to get the full groove exposed to the oil passage. It really wasn't that much material.
The 5500 peak was on a chassis dyno and IMO you can pretty much throw away most of that information. WAY too many variables on a chassis dyno. I wasn't there so I really don't know anything about how it was set up. As far as the cam...it was a Straub cam. Anytime you want to discuss it with him, feel free to call. The heads were WAY too small for a 4.25 stroke 446 ci engine who's owner wanted to make 700hp and rev to 7000rpm. We just did what we were asked to do with what we had. I don't disagree with the valve train comments, either, but the owner really wasn't listening. I did what I could with what I had to work with. He had been pretty well screwed by the last guy who built the engine and after spending a BUNCH of money, really didn't want to hear how "wrong" everything was. I finally got him to put some lighter springs on it after continually burning up pushrods. Like I said, he eventually went to T&D's and oiled through the push rods.
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A little flare at the end won't hurt anything. That's how I've been doing it for years. Some guys get carried away and ENLARGE the hole all the way through and that's where I see an issue.
So did you check the flow/velocity on the cylinder heads at all?
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Knocking spring out of it was a good deal for sure. Darn normal FE with those four 3/8 fasteners will yank the rocker assembly off the heads with too much spring. You discover it on the dyno at about 6500 when it blows holes in the valve covers and fill the room with smoke...
I know this because.... ::)
I agree on the chassis dyno data - - numbers are directionally useful but nearly meaningless.
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Knocking spring out of it was a good deal for sure. Darn normal FE with those four 3/8 fasteners will yank the rocker assembly off the heads with too much spring. You discover it on the dyno at about 6500 when it blows holes in the valve covers and fill the room with smoke...
I remember my first time..... ;)
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A little flare at the end won't hurt anything. That's how I've been doing it for years. Some guys get carried away and ENLARGE the hole all the way through and that's where I see an issue.
So did you check the flow/velocity on the cylinder heads at all?
I can see how trying to enlarge the entire passage would cause problems. I would never do that. The passage is plenty big.
Yeah, had the heads on the flow bench. Had some before and after for what I did, but without a bigger valve and some serious portwork those heads weren't going to cut the mustard.
I'll see if I can find the numbers. Heck, I don't even remember what valve it was, but I think just whatever came from Ede.
Edited:
This is my flow sheet;
2.15 / 1.65 on a 4.11 bore, 28". with ex pipe
int / ex
.2) 143 / 96
.3) 213 / 135
.4) 267 / 163
.5) 299 / 180
.6) 308 / 190
.7) 311 / 203
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So why do you think the chassis dyno results were all whopper-jawed?
I agree, I don't put much stock into chassis dyno results, they are used to tune, but I've never had a situation where the engine peaked 1500 rpm early on one.
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Knocking spring out of it was a good deal for sure. Darn normal FE with those four 3/8 fasteners will yank the rocker assembly off the heads with too much spring. You discover it on the dyno at about 6500 when it blows holes in the valve covers and fill the room with smoke...
I know this because.... ::)
I agree on the chassis dyno data - - numbers are directionally useful but nearly meaningless.
LOL... glad that didn't happen.
Chassis dyno actually showed two peaks...peak power once at 488 @ 5500, down to 449 @ 6000, and back up to (and still climbing) 464 @ 6800.
Here's the dyno sheet:
(http://www.performanceboats.com/gallery/data/500/medium/IMAG8382.jpg)
Here's the graph:
(http://www.performanceboats.com/gallery/data/500/medium/IMAG8383.jpg)
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So why do you think the chassis dyno results were all whopper-jawed?
I agree, I don't put much stock into chassis dyno results, they are used to tune, but I've never had a situation where the engine peaked 1500 rpm early on one.
See the sheet above: I never really looked at it this close. At this point in the project I had lost interest. I'm guessing converter issues and tire spin, maybe? Engine was making way more power than it was for his previous set up. It was cam'd to peak near 7000.
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20% loss......600 hp at the crank?
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20% loss......600 hp at the crank?
20% is probably on par for a C6, converter and 9". Maybe a touch more. Mind you, also, on this pull it burned up 6 pushrods if I remember.
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So you sneaked another 100 hp out of it ?
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So you sneaked another 100 hp out of it ?
I think once he worked all the bugs lout of it it was close. Like I said, then he broke the crank.
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Brent what about the passages from the cam bearings to the main oil gallery. Should the ones on 2,3 and 4 be opened up to 5/16?
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No, you don't have to open any of that up.