Need help identifying a big block

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Mike Harrington

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Bextreme04 that actually sounds like the most logical scenario for that engine. I just wish I could some info on that block number for horsepower and torque ratings and if I need to get a different prom for my truck to that engine or if the existing one will work.
Yeah I thought that balancer gadget was pretty cool too....but I've yet to find one for a one piece rear main seal. They have all been for two piece only. But I just found a clutch flywheel for the generation VI for 140$ so that ain't to bad. I will be using the truck for some serious trailer hauling of cattle, hay, cedar posts on a regular basis. It won't be a regular daily driver without pulling a trailer so I need all the torque I can get out of it
 

Bextreme04

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Unfortunately, you didn't really get any benefit from having a Gen VI bottom end. The peanut port TBI heads are some of the worst heads ever made for a BBC. Your best bang for the buck improvement would be to send the cam out to a place like Delta Cams and have it reground to a better profile($130). If you combine that with some better heads, you should have a really strong motor. You can often find some Vortec 454 truck heads for dirt cheap as they are plentiful and generally not regarded as a performance head. Delta is regrinding my Gen VI cam to a profile similar to the 454H.O. grind. I'm having my heads redone(just cleaned, checked, basic valve job, new guides, and clearanced for more lift), and also upgraded to the double spring 454 H.O. valve springs. Other than that it is a stock rebuild with bigger injectors and a conversion to the LS1 ECU. After proper tuning I'm expecting to be around 380hp/440ft-lb at the wheels. It should be right around 440/500 at the crank and you get a lot of loss in the 3/4ton running gear.

For comparison, a stock 1990 454 TBI is rated at 230hp/385ft-lb at the crank. That likely results in around 185hp/330lb-ft at the wheels... so there really is a lot to be gained for not a whole lot of cost. The other option would be to chuck the TBI setup, do the head and cam improvements, and just switch to carbureted. It's not my preference, I like the driveability and all around performance of the fuel injection, but it is MUCH simpler and cheaper.
 

Catbox

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Ok.
I got outside and took a gander at what I have.
It is a 1998 7.4L Gen VI 454.
I am positive as that is what it came out of as well as the 4L80 transmission that goes to it.

Here are some things:
Head casting numbers, both of mine are the same...
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7.4 cast into the side of the block as mentioned...
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Roller lifter holder gizmo...
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Roller cam and lifters seen...
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I did notice the push rod thingies have these stampings on them.
Not sure if they are aftermarket or not...
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Catbox

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Those lead me to look at the pushrods as well.
They measure to 3/8 inch with a nice tape at the end.

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I also have an aluminum timing cover...
 

Mike Harrington

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Bextreme04...weren't the peanut port heads strictly for torque in the 454
 

Mike Harrington

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Well I got ahold of the guy I bought the engine from and he's bringing me the computer and wiring loom that the motor was used with so at least that obstacle is over and done with.
 

Mike Harrington

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Hey catbox what's your block number? And what side of block is it on? Mine is on the passenger side at the rear of engine.
 

Mike Harrington

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Well I took the valve cover off again and peeked down inside the intake valley and didn't see any roller lifter Gizmo/plate so now it's even more confusing!! I've got a generation VI engine block that has a block number not in any database, and it's got a hydraulic cam and lifter set instead of a roller setup with a TBI intake and heads . I sure wish there was a way to track a crate engine down and see it's build specs
 

Bextreme04

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Its easy to put a flat tappet cam and lifters in a roller capable block. The full roller spider, lifters, and lifter holding blocks cost almost $600 new from GM so its a bummer that isn't there. You might have the 502 short block and just have a poorly cast "8" that looks like a 9. I've seen posts online from poeple saying the exact same thing you are, and the general consensus seems to be it is a poorly cast "8" that just looks kind of like a 9.

Can yo utake a picture of the casting number? Is there anything stamped on the side of the block near the freeze plugs?

The peanut port heads were for torque and emissions. They flow like crap and there isn't much more you can do to get bigger power numbers out of them. Lots of TBI guys just bolt on the Vortec heads for a quick bump in power output. The cam timing and cam profile is also crap on them. New heads and a decent cam will make all the difference.
 

TubeTruck

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Installing a flat tappet cam into a roller block does work but the lifters would be far below the block casting and look sunk into the lifter bore.
 

Mike Harrington

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454 7.4
Bextreme04...no it's 100% a 9. I've looked at it with a magnifying glass, took an imprint with silly putty, used paper and a pencil and rubbed the numbers on and it's definitely a 9. I'd post a picture of it but I can't seem to post any pictures on this site. Maybe it's got restrictions on new members or something
 

Mike Harrington

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Briggs,Texas
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1989
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K3500
Engine Size
454 7.4
Bextreme04...I've thought about doing the vortec heads and I've even got a decent set I've found for pretty cheap. But that damn intake that goes to vortec heads and a TBI unit is to darn expensive!!
 

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