Hi Gary.Great thread.Really great info.A few pages back you said that the DS type ign systems never had the small cap.IIRC,the DS1 did have the small cap.
Dad's Engine
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Gary, cam notwithstanding, I'm not sure I would want nearly 11:1 CR in, A a truck engine and B with today's crummey gas. Just my $.02.
I will be aiming for around 9.2-9.5:1 in my 468 build, but I know a 460 will lug down and not have any detonation issues on regular gas at these levels
I will be aiming for around 9.2-9.5:1 in my 468 build, but I know a 460 will lug down and not have any detonation issues on regular gas at these levels
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Matthew - I agree.
Bill - It's supposed to be 10.5:1, but with aluminum heads. From what I've read that's more like 9.5:1 with iron heads, which is what you are aiming for. In other words it should be fine on pump gas, and supposedly regular. (But, I think you are suggesting a lower CR because you are now realizing what the 400 can do and afraid it'll surpass the 460.
)
Bruno - I sent Tim a note asking which torque curve goes with the advanced cam. I think it is the one with more torque on the bottom and slightly less HP on top. So, that seems to be the way I'd want to go.
Also, I asked Tim if his dyno software gives Brake Specific Fuel Consumption (BSFC) numbers. If so I'd like them to compare the cams' efficiency.
Bill - It's supposed to be 10.5:1, but with aluminum heads. From what I've read that's more like 9.5:1 with iron heads, which is what you are aiming for. In other words it should be fine on pump gas, and supposedly regular. (But, I think you are suggesting a lower CR because you are now realizing what the 400 can do and afraid it'll surpass the 460.
)Bruno - I sent Tim a note asking which torque curve goes with the advanced cam. I think it is the one with more torque on the bottom and slightly less HP on top. So, that seems to be the way I'd want to go.
Also, I asked Tim if his dyno software gives Brake Specific Fuel Consumption (BSFC) numbers. If so I'd like them to compare the cams' efficiency.
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As for the distributor cap, http://en.wikipedia.org/wiki/Duraspark says:
Ford Motor Company began using electronic ignitions in 1973 with the Duraspark electronic ignition system and introduced the Duraspark II system in 1976. The biggest change, apart from the control box redesign, was the large distributor cap to handle the increased spark energy.
I realize that Wikipedia isn't always right, but I don't have another source. Anyway, I took that to mean that the big cap, and therefore the adaptor, came with DS-I. However, that may not be what was meant or it may be wrong.
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No Gary, I'm not worried that the 400 will surpass the 460, if I wanted to go up to 10.5:1, a more radical cam and a few other items, your torque peak might be lower, but the 460 will probably do quite well on regular gas, not need premium. If I wanted to dump the kind of money into mine you are spending, let's see, 460 blocks will handle out to around 700 ci, maybe more. If I were to go back to carbureted, a set of DOVE - C heads, Edelbrock intake, headers, 800 cfm TQ etc. I dare say my 6400 lb dually would walk all over a 400, even a bored out one. The hot rod world is just really discovering the 460's potential, it has been overshadowed by brand C for years because they were "cheaper to build".
On cams vs fuel consumption, overlap is what kills economy, it literally pumps raw gas down the exhaust. The 400 is an engine, that if Ford had been serious with it could have been an excellent performer, but they chose not to, whether for emission reasons or money. Any 400 or so cid engine trying to breath through a 2 barrel is a slug, with the possible exception of Chrysler's engines.
On cams vs fuel consumption, overlap is what kills economy, it literally pumps raw gas down the exhaust. The 400 is an engine, that if Ford had been serious with it could have been an excellent performer, but they chose not to, whether for emission reasons or money. Any 400 or so cid engine trying to breath through a 2 barrel is a slug, with the possible exception of Chrysler's engines.
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Gary, on the DS-I vs DS-II, the 1976 F-series came with DS-I, when I put the 390 in my 77 F-150, I kept the DS-II system (try finding plug wires for a 390 with DS-II). I wanted the hotter spark. It is a different module and coil to get the hotter spark. The cap and rotor change was to prevent cross firing as the distance between the cylinder towers was greater.
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Bill - Yep, I'm just winding you up, as the Brits say. I realize that the stroke advantage that the 400 has over a 460 isn't much.
As for the cam, I'm pushing Tim to keep it mild. This cam is supposed to have a smooth idle, so low overlap. But, I'd like to see the BSFC #'s to compare to those of the 260HR.
Are you saying the DS-I used the smaller cap and no adaptor? Just trying to learn.
As for the cam, I'm pushing Tim to keep it mild. This cam is supposed to have a smooth idle, so low overlap. But, I'd like to see the BSFC #'s to compare to those of the 260HR.
Are you saying the DS-I used the smaller cap and no adaptor? Just trying to learn.
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Yes, the DS-I had the small cap, no tower, it was basically just a solid state system.
The reason I was questioning the compression, I know people who have tried a 410 in place of the 390 and found that even with a 4 barrel the high compression gives problems on regular gas. BTW, 410 is 4.05 X 3.98, simply a stroked 390, it was used in 1966-67 Mercurys in place of the 390 2 barrel, and FWIW, had the biggest Autolite/Motorcraft 2100 ever built, a 1.33" venturii.
Question, how far is Tim boring that engine?
The reason I was questioning the compression, I know people who have tried a 410 in place of the 390 and found that even with a 4 barrel the high compression gives problems on regular gas. BTW, 410 is 4.05 X 3.98, simply a stroked 390, it was used in 1966-67 Mercurys in place of the 390 2 barrel, and FWIW, had the biggest Autolite/Motorcraft 2100 ever built, a 1.33" venturii.
Question, how far is Tim boring that engine?
Last edited by 85lebaront2; May 1, 2014 at 09:43 PM. Reason: Added question.
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Yes, the DS-I had the small cap, no tower, it was basically just a solid state system.
The reason I was questioning the compression, I know people who have tried a 410 in place of the 390 and found that even with a 4 barrel the high compression gives problems on regular gas. BTW, 410 is 4.05 X 3.98, simply a stroked 390, it was used in 1966-67 Mercurys in place of the 390 2 barrel, and FWIW, had the biggest Autolite/Motorcraft 2100 ever built, a 1.33" venturii.
Question, how far is Tim boring that engine?
The reason I was questioning the compression, I know people who have tried a 410 in place of the 390 and found that even with a 4 barrel the high compression gives problems on regular gas. BTW, 410 is 4.05 X 3.98, simply a stroked 390, it was used in 1966-67 Mercurys in place of the 390 2 barrel, and FWIW, had the biggest Autolite/Motorcraft 2100 ever built, a 1.33" venturii.
Question, how far is Tim boring that engine?
Eh, they both have short strokes, compared to the B series Cummins. 4.02 X 4.72..... Nearly 1L per cyl..........
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My dad always said "The first liar doesn't have a chance." Not that anyone is lying, but ... And, speaking of my dad, when people started bragging about the bore and stroke of their engine he'd casually quote that on the diesel locomotives he worked on. They were 9.2 x 11.1" giving 710 CI. That usually ended the discussion as no one could top it.
As for boring the 400, it will be .030" over. But Stanley Morton here in the Tulsa area is going to do it, once I get the pistons from Tim. And, that should be next week. And, Stanely has rep the engine dyno that I'm still planning to test it on. I am really curious how close to those numbers it will get.
As for boring the 400, it will be .030" over. But Stanley Morton here in the Tulsa area is going to do it, once I get the pistons from Tim. And, that should be next week. And, Stanely has rep the engine dyno that I'm still planning to test it on. I am really curious how close to those numbers it will get.
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Hey Gary,
It looks like 2 runs with a 3610 cam and one run with the 260 cam.
The slight differences in the 3610 runs would just be down to repeatability errors in the dyno load cell and different engine temp / ambient air temp.
With the same driveability in the first half of the range, it's a no-brainer to pick the 3610 with it's better 2nd half performance, particularly the torque.
It looks like 2 runs with a 3610 cam and one run with the 260 cam.
The slight differences in the 3610 runs would just be down to repeatability errors in the dyno load cell and different engine temp / ambient air temp.
With the same driveability in the first half of the range, it's a no-brainer to pick the 3610 with it's better 2nd half performance, particularly the torque.
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Sorry guys, I neglected to tell you that the top run is with the cam advanced 4 degrees. The second run is with the cam "straight up". And, these are "desktop dyno" runs with Engine Analyzer Pro, not a real dyno.
The run with the cam advanced shows what most say - that doing so adds to the bottom end and takes away from the top of the torque curve.
The run with the cam advanced shows what most say - that doing so adds to the bottom end and takes away from the top of the torque curve.