440 what am I missing here?

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Keep the fitech but have it tuned by someone with some experience with them.
 
I guess it just depends on how “mild” it can be....... and still have it remain interesting for the owner.
The 274 is going to be pretty tame.

If the owner is up for some headers, I think there would be quite a few cam choices that would make sense that are in between the TF cam, and something as small as the 274....... and between the headers, the dual plane intake, and still using a suitable cam....... the motor would be mild enough to live with, and rowdy enough to be interesting.
 
I think with the 274hr and an RPM, along with tuning the fitech to a gnats *** WITH timing control, that 440 in a light truck would put down two stripes for as long as you hold the go pedal down.
 
It depends on if the OP is willing to add headers and change the converter, too. The XR274HR has an intake closing of 38 ABDC and yields a cranking pressure of 198 PSI under the same conditions. I could see this cam running out of breath at the advertised 5800 rpm, but, if it’s installed 4 degrees retarded (110 ICL from 106) then it would easily pull past 6000 rpm and should still play nicely with the 2000 rpm stall. This would still yield 194 psi cranking.
The next step up is the 230/236 XR280HR with an rpm rating of 2200-6000 and an intake closing of 41 ABDC. That yields 196 psi cranking. Comp recommends 10.5:1 and 3.91 gears with a 2800 stall. If the OP is going to add headers and wanting to swap to a converters (custom built to the cam, gear, and vehicle weight would be best) and maximize the rpm through the midrange to the 6000 rpm peak then this cam would fit the bill. If you wanted to advance this cam 4 degrees, you’d be looking at 199 psi cranking.
As far as headers go, have you looked at any of the over the counter options for the later trucks?
 
And fair warning, the math is still incomplete (the reason I tagged AJ). It’s really the vapor pressure index (VPI) that determines just how far large you can go. But at 9.4:1, you’re safe with the Comp 274 XE. It’s parameters are 9:1 and 2000 rpm stall in a 440 with 3.55-4.10 gears. But that one in straight up with some headers and it will still carry out well on the occasional blast. There are some of the older Crane grinds with wide LSAs that would work better than expected here, too. But if you really want to take it to a different level, Oregon cam grinders or Bullet cams could set you up with a high lift/shorter duration cam with maximum .200 lift duration that would not only provide more power over a wider range, but also pull stronger vacuum and make the EFI easier to tune.
 
Garrett Ellison said:
It depends on if the OP is willing to add headers and change the converter, too. The XR274HR has an intake closing of 38 ABDC and yields a cranking pressure of 198 PSI under the same conditions. I could see this cam running out of breath at the advertised 5800 rpm, but, if it’s installed 4 degrees retarded (110 ICL from 106) then it would easily pull past 6000 rpm and should still play nicely with the 2000 rpm stall. This would still yield 194 psi cranking.
The next step up is the 230/236 XR280HR with an rpm rating of 2200-6000 and an intake closing of 41 ABDC. That yields 196 psi cranking. Comp recommends 10.5:1 and 3.91 gears with a 2800 stall. If the OP is going to add headers and wanting to swap to a converters (custom built to the cam, gear, and vehicle weight would be best) and maximize the rpm through the midrange to the 6000 rpm peak then this cam would fit the bill. If you wanted to advance this cam 4 degrees, you’d be looking at 199 psi cranking.
As far as headers go, have you looked at any of the over the counter options for the later trucks?
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Ya tried three different sets before reverting to manifolds. Between starter ,unisteer rack, steering shaft, torrion bars etc. Its tight. What kind of torque numbers are we looking at with the 274 comp cam roughly
 
With an Edelbrock performer RPM and iron exhaust manifolds, it's not necessarily be so much about the peak torque as it should produce over 500 pound feet of torque. What's is important is it's going to make gobs of torque down low near the present converters stall speed. Knowing how tight B&M converters tend to be concerning rated vs actual stall, I would put the cam in straight up so your optimizing the lower end of the rated range of the cam and intake together. I did also notice AndyF used a 2 inch super sucker spacers I had recommended in the tech article and gained more power with it. But he also tried an Edelbrock victor on the same combination with the iron manifolds and it killed as much power as the larger cam they had used. You've got those two combined working against you right now. When you change both, instead of power braking it to get the tires spinning, you'll be feathering the throttle to keep the tires from going up in smoke.
 
Garrett Ellison said:
With an Edelbrock performer RPM and iron exhaust manifolds, it's not necessarily be so much about the peak torque as it should produce over 500 pound feet of torque. What's is important is it's going to make gobs of torque down low near the present converters stall speed. Knowing how tight B&M converters tend to be concerning rated vs actual stall, I would put the cam in straight up so your optimizing the lower end of the rated range of the cam and intake together. I did also notice AndyF used a 2 inch super sucker spacers I had recommended in the tech article and gained more power with it. But he also tried an Edelbrock victor on the same combination with the iron manifolds and it killed as much power as the larger cam they had used. You've got those two combined working against you right now. When you change both, instead of power braking it to get the tires spinning, you'll be feathering the throttle to keep the tires from going up in smoke.
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Right on. I will give it a go. About the same cost as what I was planning, but less work haha can't go wrong . I'm still trying to find the sheet on my converter. I think it was the 2400 holeshot not the 2000 but I need to find the sheet to be sure will that change the cam specs, or is that a 2000,or larger type situation.
 
After reviewing the cam options and reading some of the reviews I’ve been finding there’s an awkward gap in hydraulic roller cams in this range. Some indeed say the comp 274 is undersized in a 440. But most of the 280 grinds respond well to over 3000 stall in light cars with stroker cranks.
But use this cam regardless of your converter. It’s suggested to use a 2500 rpm converter but it will make more than adequate torque in a 448 inch 440. It’s actually .520/.530 lift in the Howards catalog on a 112 LSA for decent vacuum and a 108 ICL. It listed as having good low to mid rpm torque with a 2000-6000 rpm range. Intake closing is 69 degrees ABDC and cranking compression will be 152 PSI.
Howards Cams 720555-12 Howards Cams Retrofit Hydraulic Roller Camshafts | Summit Racing
 
A quick follow up. FWIW, Howards recommends this cam for a 440 with the same TFS heads in a heavy (4200 pound) vehicle with a dual plane intake and 2200-2400 rpm stall speed.
 
I see two things that are glaring issues. Initial timing at 12 degrees is useless as tits on a boarhog. With cylinder pressure in your range, I'd pull in around 20 degrees initial and limit total to 35 degrees all in by 2500 RPM. Then go drive it. If it still acts lazy, the #2 problem I see is converter. Even a blind man would tell you that. A 2000 RPM converter is a STOCK CONVERTER for Chrysler products. You need at least a 3500 and I wouldn't be afraid to see one that will flash 4200. Converter technology isn't off Noah's Ark anymore, it's in the 21st century. You can get a custom converter that will be nice and tight around town but will flash to 5K if that's what you want when you hem it up and launch. Of course, you don't need 5K, but I sure as HELL wouldn't be afraid of 3500-4200. Not one bit.
 
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RustyRatRod said:
I see two things that are glaring issues. Initial timing at 12 degrees is useless as tits on a boarhog. With cylinder pressure in your range, I'd pull in around 20 degrees initial and limit total to 35 degrees all in by 2500 RPM. Then go drive it. If it still acts lazy, the #2 problem I see is converter. Even a blind man would tell you that. A 2000 RPM converter is a STOCK CONVERTER for Chrysler products. You need at least a 3500 and I wouldn't be afraid to see one that will flash 4200. Converter technology isn't off Noah's Ark anymore, it's in the 21st century. You can get a custom converter that will be nice and tight around town but will flash to 5K if that's what you want when you hem it up and lunch. Of course, you don't need 5K, but I sure as HELL wouldn't be afraid of 3500-4200. Not one bit.
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PRH said:
A few thoughts.......

Needs WAY more stall than anything rated at 2000.
A tight 9.5” would be more like it(3700-4000).

Initial timing is way low for a cam like that.
Should be up around 20-24.

Not the answer you’re looking for...... but........in reality....... about 10-12* less cam duration on a 112lsa would work way better........ if you care how it drives more than you care about “the big number”.
The shorter cam would be better with a milder converter, along with it being easier for the EFI to deal with.

Love the truck though:thumbsup:
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@Garrett Ellison i like that Howard’s grind. Especially if @Cool Hand wants a little more “wild” out of it like was suggested by PRH. I like the duration split for the manifolds and the 112 lsa for the fitech. I would not go much larger than that though with the converter.
 
I like it too. If it has a converter stall of 2000 rpm it is a the largest shelf cam that could be used without loosing too much low end power. If it has a 2400 rpm converter as was mentioned as a possibility, then it’s an even better match. The 112 LSA combined with 448 cubic inches is what allows 229 @ .050 duration to work with that low of a stall converter. I would prefer a 106 or 104 ICL, but Howards says it’s still okay with the TFS heads. With 2000 rpm stall it’s going to be a little soft on the bottom, but a 440 in a light vehicle it will recover quickly. If you look at what it’s working against right now, there’s no way it couldn’t help it out. Of course, if the OP wanted to run more converter, I wouldn’t tell him not to. But it would put everything where he could live with it for the time being before committing to upgrading the converter. A tight 9 or 9-1/2 inch converter afterwards would make at least that much more improvement again. But definitely going to have to lose the race single plane and the existing cam to get it to play pretty with the FI tech. Wont have to worry about headers either way, though.
 
Garrett Ellison said:
A quick follow up. FWIW, Howards recommends this cam for a 440 with the same TFS heads in a heavy (4200 pound) vehicle with a dual plane intake and 2200-2400 rpm stall speed.
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It shows 2500 plus stall on Howard's website does that matter that I have a 2400 holeshot?,and do I still need headers with this or will manifolds be ok?
 
Okay! Not perfect, but close enough to work very well with that Howards cam and the performer rpm. With the 440 and a significant boost in lower rpm torque you can expect it to stall a few hundred rpm higher than it’s rated stall speed. Keep us posted! Once you get the parts changed, the timing curve optimized, and the FI Tech tuned, I expect that you’ll be a whole lot happier with it. And if want to take it to the next level later on, then a custom converter would get it there. What size and type tire are you running on the rear right now?
 
Like AndyF said, headers would help some in the mid to upper rpm ranges. But the factory manifolds come fairly close to tri-Y design (4 into 2 into 1) headers. Looking at the chassis dyno results in AndyF’s magazine build with the Hi-Po/Magnum exhaust manifolds, I would not worry with headers unless you just want them for appearance.
 
Garrett Ellison said:
Like AndyF said, headers would help some in the mid to upper rpm ranges. But the factory manifolds come fairly close to tri-Y design (4 into 2 into 1) headers. Looking at the chassis dyno results in AndyF’s magazine build with the Hi-Po/Magnum exhaust manifolds, I would not worry with headers unless you just want them for appearance.
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Yeah, you’ll need some big drag radials or slicks before you have to worry about the converter, your highway cruise rpm at 65 is close to 3000 rpm. Your gear and tire combination at present is like 3.91-4.10 gears with a 28 inch tire. I don’t see those tires lasting very long at all. As in, good luck getting it to hook. You’ll be able to break those tires loose at any speed with the throttle when it’s right.
 
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The B&M holeshot 2400 is better than stock but not by a whole lot. It will work just fine with the Howard’s cam Garrett suggested, the RPM intake, and the manifolds. As well as your intended purpose for the truck. If you decide you want to race the truck and really make it work a custom converter is money well spent. But not until then.
 
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