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Joisey don't smell funny
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Discussion Starter #1
Ok, first some background. So I have a 460 in my 78, behind that is a ZF5-42 & divorced NP205. Gears are 4:11, and I'm now running 37" treads.

The 460 I bought newly rebuilt from a guy in PA that said he was going to use it for a project but changed his mind. It came long block, and the heads were EFI. I don't know the exact specs on it unfortunately. I cleaned & reworked my fuelie heads, mild exhaust porting/matching, smog bumps about gone, new oil seals, springs, keepers, rods. He had lifters already in. I used standard rockers. It looked like a stock timing set, but I'm no expert in that arena and I don't know the cam specs.

After a few months of driving and tweaking and not really being happy with the power or the fuel consumption, I changed out the whole intake. Swapped the edlebrock performer for a Weiand Stealth dual plane, and the Edlebrock 650 for a Summit holley style 600cfm, vac secondary. Sanderson block huggers into 3" dual exhaust, high flow muffler. It's a little loud, but not obnoxious.
I read a pile of forum threads, watched numerous youtube vids, and kept playing with the timing & such. Here's where I'm at:

It's 10-11* BTC at 850 rpm idle. I'm using ported vacuum for the advance. Manifold vacuum is at 21 at idle. I haven't run it out yet, as it feels like I need to shift up by the time I hit 3500, and with the ZF, I'm in fifth gear in no time doing 70mph. At 3500 it sounds like it's almost screaming at wide open, but maybe I'm just scared of it, lol. I'm not comfortable doing over 70 with 37's on a brinks truck wannabe!
I guess what I'm asking is more of a confirmation of sorts, that I'm where it should be for power and in the right rpm's. I've read that pretty much the norm for a standard stock timing set & cam in a 460 will create the most power around 2k, and after 35k it runs out of breath so to speak. If I wanted the upper rpm range power, I would need to change the cam. I don't see where it originally being an EFI motor, if putting fuelie heads on took away from anything. Don't get me wrong, it runs really good, and has good get up 'n go in the lower rpm's for a 3 ton chunk. Just sometimes I feel like I should be getting one RCH more, or maybe I'm over thinking it.

Any opinions or thoughts are welcomed please.
 

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Ford Hoarder
78 & 92
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I thought the intake and exhaust ports where different on the EFI heads. Therefore you cannot really put carb stuff on efi heads, or go the opposite way either. Not without adpaters anyways... What your saying makes me think that is not the case. Do you happen to have the casting #s off the heads? Something seems a bit off in what your saying from the info I have gathered for my own 429/460 builds.

That said, I would not be afraid of rpm, mine have hit 5k+ rpm regularly, thought the EFI in the 96 does seem to fall off as it gets above 4500 rpm.

A carb spacer, about 1/2" would help move your power band up a bit without doing a whole lot of work.

The CAM is the heart of the engine though, if its wrong for what you want you'll never get what you want... You almost literally should pick a cam first, then build the engine around that cam, at least when it comes to picking out the intake/heads/exhaust.
Also I know not cheap but a wide-band o2 is a great piece of tuning equipment, can least tell you if your close on your tune as the rpm comes up.
 
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Joisey don't smell funny
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Discussion Starter #3
I didn't use the EFI heads, I reworked the carb'd heads I had. I've been looking at O2's, just don't feel like dropping the coin right now.
The way it runs between 18k and 28k makes me sure he had stock cam & timing gears put in when it was built. With the other components I've got in it, it just falls shy of that "oomph".
 
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78 Custom - 460 - NP435 - NP205 - Sniper EFI - HyperSpark Ignition - 4.56 Gears - Front/Rear Lockers
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2,016 Posts
I'm definitely no expert, but I've had a couple of 460's. Stock and built.

If I remember correctly, I believe a stock 460 peaks in horsepower somewhere in the 4000-4500 rpm range and peaks torque closer to 2k. They are pretty stout from the factory and can spin higher than that, but with no benefit in stock trim.

With my current setup being with a manual tranny (NP435) I've noticed that both my old 351M and my current 460 both sound like they're going to explode when I rev them up north of 2800. I don't know if it's a manual thing, a 4x4 thing (t-case in the equation), or what, but when I had an auto behind a 460 in a 2wd I never got nervous revving things to 5k and cruising the freeway at 3k. Everything just sounded and felt way smoother. With the way things are in my current setup the exhaust starts to get pretty loud by 2500 rpm and that's when I shift under normal driving, aka around town. My current 460 was dyno'd and did pulls up to 5300, so I feel comfortable revving it up to 5k (where it peaked power), but boy does it sound scary as shit on the street if I rev it that high. lol

As far as getting a little more grunt down low you could put in a pre-72 timing set and have the timing "straight up". It will advance the timing back to pre-smog era cam timing and essentially shift the power band down a couple hundred rpm. That's with a stock cam though, if it has an aftermarket cam that's what degreeing the cam is for.

From reading a lot over on 460ford I've heard that the Performer is preferred over the stealth for lower rpm power. They say the runners are longer and larger on the Stealth which gives you more power higher in rpm which is probably why the operating range for the Stealth is "idle-6800" vs the Performer's "idle-5500" even though they are both dual plane intakes.

With as much vacuum as you have at idle I would assume you've got a stock cam or something very close to that. Anyway, not sure if any of that helps, but those are the things that came to mind.
 

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Joisey don't smell funny
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Discussion Starter #5
Thanks for the input Doose! That pretty much echos what I'm getting here.
 

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1978 Bronco Ranger XLT, 400/C6 92 K documented miles &1994 Bronco,XLT 85K original miles
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I'm definitely no expert, but I've had a couple of 460's. Stock and built.

If I remember correctly, I believe a stock 460 peaks in horsepower somewhere in the 4000-4500 rpm range and peaks torque closer to 2k. They are pretty stout from the factory and can spin higher than that, but with no benefit in stock trim.

With my current setup being with a manual tranny (NP435) I've noticed that both my old 351M and my current 460 both sound like they're going to explode when I rev them up north of 2800. I don't know if it's a manual thing, a 4x4 thing (t-case in the equation), or what, but when I had an auto behind a 460 in a 2wd I never got nervous revving things to 5k and cruising the freeway at 3k. Everything just sounded and felt way smoother. With the way things are in my current setup the exhaust starts to get pretty loud by 2500 rpm and that's when I shift under normal driving, aka around town. My current 460 was dyno'd and did pulls up to 5300, so I feel comfortable revving it up to 5k (where it peaked power), but boy does it sound scary as shit on the street if I rev it that high. lol

As far as getting a little more grunt down low you could put in a pre-72 timing set and have the timing "straight up". It will advance the timing back to pre-smog era cam timing and essentially shift the power band down a couple hundred rpm. That's with a stock cam though, if it has an aftermarket cam that's what degreeing the cam is for.

From reading a lot over on 460ford I've heard that the Performer is preferred over the stealth for lower rpm power. They say the runners are longer and larger on the Stealth which gives you more power higher in rpm which is probably why the operating range for the Stealth is "idle-6800" vs the Performer's "idle-5500" even though they are both dual plane intakes.

With as much vacuum as you have at idle I would assume you've got a stock cam or something very close to that. Anyway, not sure if any of that helps, but those are the things that came to mind.
 

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78 & 92
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Makes more sense on the heads. You actually should have gotten a small compression bump from putting the carb heads on the efi motor (if i remember right)
No clue if helpful or not and yes I know its a little long. Multiple times near 5800 rpm in this vid. Its mostly in 4lo as well (is what the howl noise is)
specifically look @ 6:40, 7:16, 10:00

Also what is your total timing at? And did you set the base timing with or without the vacuum line connected. With 20hg at idle it could be advancing the dist. when you set it, so when you get into the throttle, its no longer where you think it is. This is especially true with the stock style duraspark dist., if that is what you have. When I as running one I had to have the vacuum advance disconnected as it was very unpredictable on what it was doing (mine had an issue somewhere).
-Long winded way to say that, I would consider re-curving your distributor, and/or checking the timing at several different rpm ranges.
 
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