97 454 L29 Vortec into a 80 K25

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Bextreme04

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I’m just keeping it black like it was from the factory. I’ll do the headers, intake, and accessories aluminum color.
 

Bextreme04

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Got the new lifters and retainers in
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Then I bolted the spider retainer on and set the head gasket and driver side cylinder head on.
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Then I realized I had decided to use new head bolts and had thrown away the old ones so that I wouldn’t be tempted to reuse them. So I’ll go get a new set of mahle bolts tomorrow and get the heads installed. Then I need to get the holes plugged on the upper intake and prep the block and intake parts for paint.

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Bextreme04

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Tried to go get new head bolts today. I was planning on getting the Mahle ones as they are the only alternative to felpro that can be had easily locally. Turns out they are direct order from the manufacturer only and I would have to pay shipping and wouldn’t get them until next week. Ain’t nobody got time for that. So I got the felpro set instead. They had them in stock and they look identical to the factory ones.
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it’s nice they come with the thread sealant already(all head bolts go through to the water jackets and MUST have thread sealant) but I didn’t trust it completely and used some PTFE thread sealant over the top of what was already there just to make sure. Then I snugged them down with my trusty electric drill using a half inch socket to save some time and then torqued in three steps using this sequence and specs. Final torque is spec’d to 85lb-Ft for the Gen VI heads, so I just did the final step at 85 instead of 80.
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So that’s one side some and then on to the other side!
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68post

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454, TBD
What did Delta grind the cam specs to ?
 

Bextreme04

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What did Delta grind the cam specs to ?
Post #8 on page 1 has a pic of the cam sheet. Its a pretty mild tow/RV/mileage cam since I'm still going to be using the factory MPFI. The lift tops out at .510, which is perfect for the L29 heads that max out flow at around .500. Another nice thing is that they set it up 3.5 deg advanced, which is much nicer than the ~6 deg retarded of the stock cam grind.

The stock motor, at 288,000 miles, leaking oil and coolant everywhere and overheating, had sooooo much more power than my current 350 that I'm REALLY excited to get this thing done and installed in the truck. I'm really trying hard to hold it together and take my time to do it right and make it look nice at the same time.

My excitement is telling me to just slap it together and send it.:emotions122:
 

68post

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Post #8 on page 1 has a pic of the cam sheet. Its a pretty mild tow/RV/mileage cam since I'm still going to be using the factory MPFI. The lift tops out at .510, which is perfect for the L29 heads that max out flow at around .500. Another nice thing is that they set it up 3.5 deg advanced, which is much nicer than the ~6 deg retarded of the stock cam grind.

The stock motor, at 288,000 miles, leaking oil and coolant everywhere and overheating, had sooooo much more power than my current 350 that I'm REALLY excited to get this thing done and installed in the truck. I'm really trying hard to hold it together and take my time to do it right and make it look nice at the same time.

My excitement is telling me to just slap it together and send it.:emotions122:


Thanks, I did find post #8 but could enlarge it to see the durations or lobe seperation. I'm sure the advance will be a great boost off-idle TQ.
I do have an L29 core sitting for several yrs now but have decided to use an older block to have a mech fuel pump, and with vortec heads to build an 8.0L clone with a little warmer cam.( 496 or 506ci )
I am fighting with the notion to use the #781 heads that core came with and domed pistons, but I'd be better off and likely money ahead,( I think ?), to use L29 heads and flat pistons for 87 octane, and giving away some HP.
Buuuut, I may not get to drive it enough to worry about fuel costs also !!!??

I'll stay tuned, good luck, and smooth sailing !
 

Bextreme04

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Thanks, I did find post #8 but could enlarge it to see the durations or lobe seperation. I'm sure the advance will be a great boost off-idle TQ.
I do have an L29 core sitting for several yrs now but have decided to use an older block to have a mech fuel pump, and with vortec heads to build an 8.0L clone with a little warmer cam.( 496 or 506ci )
I am fighting with the notion to use the #781 heads that core came with and domed pistons, but I'd be better off and likely money ahead,( I think ?), to use L29 heads and flat pistons for 87 octane, and giving away some HP.
Buuuut, I may not get to drive it enough to worry about fuel costs also !!!??

I'll stay tuned, good luck, and smooth sailing !

I think maybe it couldn’t be made bigger because I uploaded it as a thumbnail instead of a picture. Here’s the full photo.
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The combo of the flat top pistons and the L29 heads gives great daily driver CR and is pretty efficient. I’ve seen people in stock or slightly modified GMT-400 L29’s claim to get 12-15mpg, which is pretty awesome for a 454 making 3-400hp and 500lb-ft of torque.

One thing to look out for with the L29 heads is that there is no heat riser crossover, so it doesn’t do well with a carbureted application. Also the Gen V and Gen VI BBC has a parallel coolant flow that is different from previous generations and will need some interesting head gasket things depending on which block is combined with which heads.
 

Bextreme04

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Well, didn’t get any work done on the motor tonight. Saw a Facebook marketplace ad pop up in @Catbox ’s neck of the woods for a 60 Gal craftsman air compressor... for $20!!! So needless to say I went up and got it.
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The oil free pump threw a rod and it’s old enough that you can’t get parts for it. Thankfully the motor is a 6hp 240v 1ph and is still in perfect working order. My neighbor just so happened to have his compressor lose the motor a few weeks ago and he bought a new one. He’s gonna bring it o we tomorrow and I’ll see if I can his pump working with my motor and have a working 60 gal for $20 and a few hours of my time!
 

Catbox

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Market Place can get you to do funny things.
I went to McMinnville last week for a set of headers that may or may not work on the truck.
But the deal was just to good to pass up.

Nice score on the tank!
 

Bextreme04

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Alright, got the shop somewhat sorted and got some time again to work on the engine.

I wanted to check the pushrod length because it seemed the ones my machine shop ordered were much shorter than the stock ones.

After fiddling with it for a while I realized that the measured length was pretty darn close to the ones the shop had ordered. The stock ones were a strange length that seemed almost based on the metric length, but the new ones were almost exactly .100 shorter. Which then clicked in my head and I realized that the heads had .05 taken off and the deck had also been milled the same amount. So I put the whole valve train together with those pushrods and they seem to be perfect.
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The Gen VI BBC has this cool clip-in heat shield tray that keeps the hot oil from spraying up onto the intake.
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Bextreme04

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Then I punched out the old seal on the timing cover and put a timing tape on the new harmonic balancer and clear coated it to keep it from flying off.

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I still need to remove the cam gear and locktite the cam retaining plate bolts, since I forgot to do that when I assembled it the first time. Then I need to tack weld the oil pickup tube and then clean and paint everything.
 

Bextreme04

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Everything has been on hold while my power has been out for the last 12 days. Power just got hooked up today, so hopefully I can get some stuff painted tonight and move forward with the build. Picked up a non-rust filled radiator from a 1998 C3500 with the 7.4 and an electric fan setup from a 2011 2500HD with HD cooling for $100 from pick a part. I should be able to set everything up and start it on the engine stand to make sure I didn’t screw anything up too bad and work through electrical issues before it’s all slapped in the truck.

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Bextreme04

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Annnnnnnd connecting rod carnage....
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looks like the old engine just wasn’t going to wait for me to be ready

The engine is pretty much ready once I paint and assemble the accessories. I have all the parts to get the wiring harness finished and routed where it needs to go before firing it up and running it on a stand.

Transmission still needs to come apart and get inspected before I order parts for the rebuild. And I need to order the rebuild kit for the transfer case. I might just pull that now since the truck isn’t going anywhere anyways. Get the transfer out so I can machine the index ring on the adapter, clean and rebuild the transfer, paint it, and get the electronic vss sensor in it. I need to get the transmission parts ordered soon as they apparently can take a while to ship from the company I want to get them from.
 

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