422 dyno fail

JedIEG

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Maybe this is a stupid question, but did you check that the lifter oiling rings don't pop out past the top of the lifter bores or have the block bushed to deal with that? I know my 340 block could not run a HRL with .570 lift in stock form.
 

EchoSixMike

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That seems like it's down a cylinder, what do the plugs look like? Were there air/fuel ratios recorded?

I did a 406" B block with mildly rubbed on 452 heads that flowed 245cfm@.5, 8.2:1 compression, Erson 230 something hydraulic roller, with an out of the box Holley 750 vacuum secondary on a Performer(not rpm) intake and it made 435hp and 445ft-lbs. I would expect at least that level of performance from the 422in small block, expecting to push more like 500'ish numbers actually. S/F....Ken M
 

moparstud440

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May want to check the plugs. My wife's uncle had a motor on the dyno this past winter. He was trying some different intakes. Motor was making like 630HPish but after one intake swap it dropped to 400 or so. Ended up having a bad plug even though it only had a few dyno pulls on it. Put a new plug in and the HP went back up to 600ish.
 
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Jim Ward

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Well the intake and carb helped some but it is still lacking. Made 480ft lbs and 396 hp. I will put the motor in the car and then pay for a chassis dyno as in this session that I paid for I only have got 4 pulls. The cam was supposedly installed straight up.

EB1D4034-D7F3-4434-817C-6718AA9BFBF7.jpeg
 

Demonx2

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I'd say 55 #-ft and 45 hp for a carb and intake is a pretty darn good improvement! There's still more in there somewhere...now either headers or cam. Others will chime in I'm sure but great job bumping it up already!
 

jimjimjimmy

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when you have almost 100 more tq than hp it's saying i can't breathe from what i understand . but it will still be fun .
 

Jarlaxle

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HP is low for sure, and the torque is shy of potential also. A stock 360 magnum long block with a mild street cam/air gap and 750 DP will make 340 hp pretty easy

A truck long block with an extra point of squeeze and a cam made 400hp as a crate motor 25 years ago! (The 380hp advertised rating was for the lawyers.)
 

Jarlaxle

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Well the intake and carb helped some but it is still lacking. Made 480ft lbs and 396 hp. I will put the motor in the car and then pay for a chassis dyno as in this session that I paid for I only have got 4 pulls. The cam was supposedly installed straight up.

View attachment 1715934535

OK, one thing jumps out at me immediately: it's nosing over. Torque peak is 4K, it's down 30ft-lbs at 4500 and 60ft-lbs at the 5000RPM power peak. It loses 100lb-ft in 1400RPM.

Clearly, something is choking this engine. My first question is one I haven't seen, though I admit I haven't read all 6 pages of posts: how big were the headers? I wonder if the shop's "SB Mopar" dyno pipes were small-primary. I think this beast needs decent-sized (1 3/4", maybe 1 7/8") header primaries.
 

autoxcuda

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OK, one thing jumps out at me immediately: it's nosing over. Torque peak is 4K, it's down 30ft-lbs at 4500 and 60ft-lbs at the 5000RPM power peak. It loses 100lb-ft in 1400RPM.

Clearly, something is choking this engine. My first question is one I haven't seen, though I admit I haven't read all 6 pages of posts: how big were the headers? I wonder if the shop's "SB Mopar" dyno pipes were small-primary. I think this beast needs decent-sized (1 3/4", maybe 1 7/8") header primaries.

They don’t look like step headers. Dyno sheet says Shoenfield. They don’t make anything smaller than 1 3/4 for non W heads

They don’t look like anything on Shoenfelds website.

upload_2022-5-28_18-51-19.jpeg


upload_2022-5-28_18-51-45.jpeg
 

Jim Ward

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OK, one thing jumps out at me immediately: it's nosing over. Torque peak is 4K, it's down 30ft-lbs at 4500 and 60ft-lbs at the 5000RPM power peak. It loses 100lb-ft in 1400RPM.

Clearly, something is choking this engine. My first question is one I haven't seen, though I admit I haven't read all 6 pages of posts: how big were the headers? I wonder if the shop's "SB Mopar" dyno pipes were small-primary. I think this beast needs decent-sized (1 3/4", maybe 1 7/8") header primaries.
These are my Doug’s headers and are 1 5/8” primaries.
 

crackedback

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My guess at this point, you have a valve train issue.

spike drop spike drop spike drop... equivalent HP at 4400 and 5000 rpm, yep totally normal. NOT

Something isn't right for that to be consistent through the pull.

It ISN'T the headers...
 

autoxcuda

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Well on the bright side...

Before: Offy Port-O-Sonic street single plane and Edelbrock 750 carb…

After: Edelbrock Air Gap dual plane, 850 Quick Fuel

Picked up 44 HP and 56 TQ
 

rumblefish360

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My guess at this point, you have a valve train issue.

spike drop spike drop spike drop... equivalent HP at 4400 and 5000 rpm, yep totally normal. NOT

Something isn't right for that to be consistent through the pull.

It ISN'T the headers...
I’m thinking valve springs. IDK for sure.
 


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