454 (7.4L) swap / repair options - 1999 Suburban K2500

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Erik the Awful

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In most states, when you're towing the speed limit is only about 55 or so anyway.
We've towed the race car to Atlanta, Alabama, Illinois, Colorado, Florida and back, and drove 75 mph most of the way. I hadn't heard this, so I looked it up. Most states the speed limit is the same when you're towing. There are a few states where your speed is limited, but it's a mish-mash of laws. If you're worried, print this out, laminate it, and keep it in your truck. https://drivinglaws.aaa.com/tag/trailer-speed-limits/
 

HotWheelsBurban

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Don't know how many of y'all have towed any type of U Haul trailer, but they have a rule that their trailers are not supposed to be towed at speeds above 55 mph. They use bias play tires on them, that are not rated for higher speed. And I know from experience that a heavily loaded trailer--even if loaded properly and hitched right-- is something that will affect your performance and you will need to plan your stops and change how you drive your truck.
 

454cid

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Don't know how many of y'all have towed any type of U Haul trailer, but they have a rule that their trailers are not supposed to be towed at speeds above 55 mph....

Many of the ones I've seen actually say 45mph on a decal! I kinda laugh when I see that. I think it's more of a risk reduction thing for the company, but it'a backwards since traveling super slow on the highway is actually making yourself an obstacle. Most people don't actually go that slow when pulling one, Thankfully.
 

Gibson

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Yeah,, I've gone and chased down rabbit holes.
For the OPs situation, probably the most cost effective solution is just to re-build the original 454.
I've never built a BB, but it seems that just a simple/low cost build with some cam/injector/headers, that you can have a good engine that will last a long time and provide enough power and torque.
 

Mangonesailor

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Yeah,, I've gone and chased down rabbit holes.
For the OPs situation, probably the most cost effective solution is just to re-build the original 454.
I've never built a BB, but it seems that just a simple/low cost build with some cam/injector/headers, that you can have a good engine that will last a long time and provide enough power and torque.

A guy on FSC built one. ZZ502 cam, forged internals, I think slightly bigger valves, headers, injectors. He may have shaved the heads a smidge (I gotta look it up) and dyno'd in the high 400s or low 500s with 600-some lbft.

Should make sure your trans is good to go (built) and do the double-apply mod for the third gear piston. HD2 or transgo makes a kit which instructs you on this...
 

b454rat

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A very smart (****** genius) engine builder told me 'you can put a flower pot in place of a piston in a big block and still make power'

Ive owned many 454s. Never ran anything smaller. Only bad one I had was my first one, that had a flat cam n bout 6:1 compression. Rebuilt it and made about 500 or so horses with it. Late 90s motors (maybe even later years too) had very conservative tunes, so **** wouldn't break and would last at least past the warranty. Put a tune in it, and it will wake it up.
 

Mangonesailor

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A guy on FSC built one. ZZ502 cam, forged internals, I think slightly bigger valves, headers, injectors. He may have shaved the heads a smidge (I gotta look it up) and dyno'd in the high 400s or low 500s with 600-some lbft.

Should make sure your trans is good to go (built) and do the double-apply mod for the third gear piston. HD2 or transgo makes a kit which instructs you on this...

Looking in my database from that thread, I found the following:

User is Bankspower98 and claims 430hp and 667lbft@3200.

There's some roller rocker arms that were recommended and I believe they're Comp RPR205 fyi . There's not many that'll fit under our valve covers... and we can't just swap covers because of the throttle body. Plenum spacers existed...
But hood clearance...
 
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White96k2500

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Looking in my database from that thread, I found the following:

User is Bankspower98 and claims 430hp and 667lbft@3200.

There's some roller rocker arms he recommended and I believe they're Comp RPR205 . There's not many that'll fit under our valve covers... and we can't just swap covers because of the throttle body. Plenum spacers existed...
But hood clearance...
This thread is really making me want to throw a mild built big block in place of my 350
 
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