440 what am I missing here?

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AndyF said:
Manifolds will work just fine if you want low end torque. A set of custom headers will add some power but not a lot from 0 to 4500 rpm. If you want to build headers then that is fine but keep them small. 1 3/4 at the largest. I have 1 3/4 inch headers on my Pro Street Duster and it makes plenty of power. Way more than I need on the street.

A small cam will help your combo a lot. I used the Mopar .528 in my Coronet with ported Edelbrock heads and HP manifolds. That engine would spin the tires all the way thru first and second gear. It made 475 hp at the rear tires on the chassis dyno. That was with a Performer RPM intake and a 800 cfm Edelbrock carb. A cam in that range would wake up your truck.

This is all assuming that you don't have some other big problem with the engine. I still think you need to double check everything on the engine before you start swapping parts. If the engine was put together by someone without a lot of experience then there are all sorts of things that could happen. The cam can be retarded a tooth, the firing order can be wrong, the rings put in upside down, etc. The list of possible mistakes is endless......
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Had an experienced guy assemble it with my help. He is just a chevy guy. So know rings ,and cam ate installed well. I will have him help with the cam swap as well because he us very ocd and meticulous as far as double checking direction and clearances... hope she flies some day soon thanks again,and I will let you all know what comp suggests
 
Was the camshaft degreed when assembled the first time?
 
A decent shelf grind based on Andy's criteria, but not quite as much .050 as the .528/284 Mopar solid. Being a single pattern camshaft, it probably would work better with headers.
Howards Cams Retrofit Hydraulic Roller Camshafts 720555-12
If you stay with exhaust manifolds, then I really like this grind, but availability may be somewhat sketchy now. Crane lists it as being best with 2000 rpm stall. If it were me, I would risk leaving some power on the table and run with this because it should play very well with the FI Tech.
Crane Hydraulic Roller Camshafts 689521
One of Comp's XE 274 grinds is also very good, but would be even better if ground from a 110 LSA to a 112-114 (depends on what Comp says is best for the FI). It would easily make the most power of all three of these cams.
 
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@Garrett Ellison while I like your thinking with the above camshaft recommendations I still would like to know where this long block ended up compression wise. He says forged pistons, 040 over but really we have no idea. I just built a 9.5:1 (measured) pump gas BBC for my boat and I used a cam with 230/236 @050 on a 112 and I think it’s a little large. In a heavy car it would be a slouch. But I did it because the thing lives at 4-4500 rpm. I’d really like to know where this engine is as far as compression before making a cam recommendation. Hell he could be alright if he just moves the current cam around a few degrees.
 
TT5.9mag said:
@Garrett Ellison while I like your thinking with the above camshaft recommendations I still would like to know where this long block ended up compression wise. He says forged pistons, 040 over but really we have no idea. I just built a 9.5:1 (measured) pump gas BBC for my boat and I used a cam with 230/236 @050 on a 112 and I think it’s a little large. In a heavy car it would be a slouch. But I did it because the thing lives at 4-4500 rpm. I’d really like to know where this engine is as far as compression before making a cam recommendation. Hell he could be alright if he just moves the current cam around a few degrees.
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Yes, right on and thank you! It’s a little hasty to say grinds A/B/or C at this point. Even though the 74 cc chambers help, if it has some old school speed pro pistons that are set .080 below deck combined with a .050 head gasket (for example, hopefully it’s nowhere close to these figures) all these choices may be too large.
Knowing the the cranking compression is key here! Being we have a cam card, knowing the installed ICL would be a bonus for calculating the actual compression, to within a couple of percent anyway.
 
Garrett Ellison said:
Yes, right on and thank you! It’s a little hasty to say grinds A/B/or C at this point. Even though the 74 cc chambers help, if it has some old school speed pro pistons that are set .080 below deck combined with a .050 head gasket (for example, hopefully it’s nowhere close to these figures) all these choices may be too large.
Knowing the the cranking compression is key here! Being we have a cam card, knowing the installed ICL would be a bonus for calculating the actual compression, to within a couple of percent anyway.
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Exactly
 
Garrett Ellison said:
Yes, right on and thank you! It’s a little hasty to say grinds A/B/or C at this point. Even though the 74 cc chambers help, if it has some old school speed pro pistons that are set .080 below deck combined with a .050 head gasket (for example, hopefully it’s nowhere close to these figures) all these choices may be too large.
Knowing the the cranking compression is key here! Being we have a cam card, knowing the installed ICL would be a bonus for calculating the actual compression, to within a couple of percent anyway.
Click to expand...
Have not had time to do a compression test yet because the truck is in storage not at the shop for the moment until I finish the current customer build. The pistons are flattop forged pistons that came with the fed mogul rebuild kit but I don't know the piston deck clearance.The block was not decked so should be stock. Stroke is 3.750, bore is 4.350 combustion chamber on head is 78cc. The gaket that came with the trickflow heads is .051 with a 4.380 diameter, but the builder said he used the fed mogul gasket for some reason. Not sure why maybe it was the thickness IDK. If anyone can find the info on the fed mogul rebuild kit gasket that would help but I still need deck clearance to get compression. The cam was not degreed when installed. Believe it had a peg ,and you just lined up the dots on timing gears will look at pics and see. Has a comp cams double roller timing chain. Just spouting info at this point dont know if any of this helps
 
Cool Hand said:
Have not had time to do a compression test yet because the truck is in storage not at the shop for the moment until I finish the current customer build. The pistons are flattop forged pistons that came with the fed mogul rebuild kit but I don't know the piston deck clearance.The block was not decked so should be stock. Stroke is 3.750, bore is 4.350 combustion chamber on head is 78cc. The gaket that came with the trickflow heads is .051 with a 4.380 diameter, but the builder said he used the fed mogul gasket for some reason. Not sure why maybe it was the thickness IDK. If anyone can find the info on the fed mogul rebuild kit gasket that would help but I still need deck clearance to get compression. The cam was not degreed when installed. Believe it had a peg ,and you just lined up the dots on timing gears will look at pics and see. Has a comp cams double roller timing chain. Just spouting info at this point dont know if any of this helps
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It helps for sure. While we won’t know exactly, we now have more info. And that helps make better choices. Now get that compression test done! :poke:
 
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A few things add up.
Single plane intake ( high rpm)
Low gears NG
That cam ( high rpm)
Exhaust manifolds NG
That is an Awesome truck.!!
Should roast the tires.
Have to get things to work together
You either build a low end torque monster set up ( preferred for street )
Or
A high rpm motor ( drag )
Settle on the true use , then build towards that.
following.....
Best of luck !
 
Okay, some fast figures with the Summit Racing compression ratio calculator and volumetric measurements plugged in where applicable, and compression heights listed.

If you have the Speed-Pro L-2355 40 (C.H. 2.061) with 7cc's of valve relief at .021 below stock deck your compression would be "around" 9.84:1
This is your best case scenario.

If you have Speed Pro L-2266F 40 (C.H. 1.991) without reliefs it would be .091 below deck at TDC. That yields a compression ratio of 9.05:1.

The next on the list is nearly identical but a Sealed Power 350 NP 40 (C.H. 1.990) at .092 below deck for a negligible change of 9.03:1

Then, if you want to see how bad it can be, there's Sealed Power 424 NP. (C.H. 1.912) It was probably a replacement for the 1966 440 with the 516 heads and steel shim head gaskets or the smogger truck engines of the late seventies. It could be used in a stock 400 to give .023 below deck. But it's .170 (!) below deck in a stock 440. Or 7.88:1. I hope To God you do not have this piston...
Of course, these are all subjective because block casting deck heights are oftentimes off to the high side on most Mopar blocks I've seen. So these compression ratios are almost always .1-.2 lower or more than best case figures.
If you happen to know the piston numbers, it would get us closer, but the compression test is needed regardless.
 
Garrett Ellison said:
Okay, some fast figures with the Summit Racing compression ratio calculator and volumetric measurements plugged in where applicable, and compression heights listed.

If you have the Speed-Pro L-2355 40 (C.H. 2.061) with 7cc's of valve relief at .021 below stock deck your compression would be "around" 9.84:1
This is your best case scenario.

If you have Speed Pro L-2266F 40 (C.H. 1.991) without reliefs it would be .091 below deck at TDC. That yields a compression ratio of 9.05:1.

The next on the list is nearly identical but a Sealed Power 350 NP 40 (C.H. 1.990) at .092 below deck for a negligible change of 9.03:1

Then, if you want to see how bad it can be, there's Sealed Power 424 NP. (C.H. 1.912) It was probably a replacement for the 1966 440 with the 516 heads and steel shim head gaskets or the smogger truck engines of the late seventies. It could be used in a stock 400 to give .023 below deck. But it's .170 (!) below deck in a stock 440. Or 7.88:1. I hope To God you do not have this piston...
Of course, these are all subjective because block casting deck heights are oftentimes off to the high side on most Mopar blocks I've seen. So these compression ratios are almost always .1-.2 lower or more than best case figures.
If you happen to know the piston numbers, it would get us closer, but the compression test is needed regardless.
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Nice research. On the “best case scenario” with that cam I’m betting less than 130psi of cranking pressure. Not good. And it only gets worse from there.
 
TT5.9mag said:
Nice research. On the “best case scenario” with that cam I’m betting less than 130psi of cranking pressure. Not good. And it only gets worse from there.
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Testing compression tomorrow. Will also grab build book to get you guys piston info. Stay tuned,and thanks a ton
 
OK here we go the pistons are speedpro. L-2266F30 forged flat 4.350
Summit number SLP-L2266F30
Compression I tested on #1 got just over 150
#2 got around 157
#8 got just under 160
All were done on a us general tester so thats as precise as I can get
Thanks guys
 
More than I thought you’d have. That’s a 030 over piston. Please tell me it did not go in a 040 over bore. You’re original post says 040 over.
 
Here’s the thing with a compression test with a hyd roller.......
Especially if it was done “cold” after the motor had sat a while.......

If the OP has the TF heads that come with the hyd roller springs...... it’s a pretty stout spring.
150+ on the seat, about 440lbs/in.

Most hyd roller lifters are going to be bled down after sitting a while with that kind of spring load, which makes the effective duration less for the test....... which makes the cranking compression numbers go up.
(It doesn’t always work out like that...... but it does periodically)

In any case, an L2266 in an uncut block is going to sit about .090 down the hole.

At .040 over, assuming a .040 thick gasket and uncut heads..... it’s at about 9.25:1 compression.

At this point I’d say it’s a pretty safe bet to recommend a noticeably shorter duration cam and a dual pane intake manifold.
And even then...... it might still want more stall speed(which would then be a try it first and see what happens situation).
 
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PRH said:
Here’s the thing with a compression test with a hyd roller.......
Especially if it was done “cold” after the motor had sat a while.......

If the OP has the TF heads that come with the hyd roller springs...... it’s a pretty stout spring.
150+ on the seat, about 440lbs/in.

Most hyd roller lifters are going to be bled down after sitting a while with that kind of spring load, which makes the effective duration less for the test....... which makes the cranking compression numbers go up.
(It doesn’t always work out like that...... but it does periodically)

In any case, an L2266 in an uncut block is going to sit about .090 down the hole.

At .040 over, assuming a .040 thick gasket and uncut heads..... it’s at about 9.25:1 compression.

At this point I’d say it’s a pretty safe bet to recommend a noticeably shorter duration cam and a dual pane intake manifold.
And even then...... it might still want more stall speed(which would then be a try it first and see what happens situation).
Click to expand...
I ran it for a few minutes before testing
 
Yep! I’m coming up with less pressure than you are showing using the average barometric pressure for your area today. But when I use the listed chamber volume of 74cc’s instead of 78 cc’s and err to a heavy factory deck cut on the block to 10.72, then I’m coming up with 10.4:1. That equates to 146 psi cranking pressure, so given the bleed down PRH mentioned I could see that as being pretty close. Now, for the sake of comparison, let’s advance the cam timing four degrees to 100 degrees ICL and intake closing of 68 degrees ABDC. now we have a cranking compression of 152 PSI. We need a much earlier intake closing event or shorter duration here to get the pressure up to acceptable levels with those gears and the tight converter.
 
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