L29 engine specs

[Yamaben]

I bought a L29 from Craigslist. I want to share what I have found out about this engine.

10237297 casting number on the block

10141297 casting number on the heads

Flat top pistons
Oval port intakes
4 bolt main caps

I measured the combustion chambers at 100cc

Using a CR calculator puts this cr at 9.4:1

This thing seems like it should make big power with the right cam and intake.
These heads actually look pretty good to me, if you can overlook the weight and the non-adjustable valve train.

Sorry if this is all common knowledge to everyone. This is the first gen 6 I have ever had. I was expecting dish pistons and peanut ports

 

[Jrgunn5150]

NO, they are oval ports, and apparently they really wake up with a decent exhaust.

 

[Christian Steffen]

I would swap to an adjustable valve train (there are kits available), roller tip rockers will also fit under the stock valve covers with the use of short poly locks, granted if you swap intake manifolds you could run taller valve covers. A cam swap is a must on these, they came from the factory retarded 6 degrees and they're pretty small. Check out this super chevy article, they can make pretty good power without a ton of work if you're not running the stock intake manifold.

http://www.superchevy.com/how-to/en...power-on-a-junkyard-454-with-simple-cam-swap/

 

[Yamaben]

Thanks buddy! I'll give that cam a try

You must be registered for see images attach

 

[Christian Steffen]

Good luck, let us know how it turns out!

 

[Yamaben]

The rings were rusted in the grooves, and the second compression ring was broken on one of the pistons. Overall the engine is in great shape tho

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[Yamaben]

The bores are really nice tho. The taper and out of round are within .001" on all the cylinders and the the top compression ring end gap looks like new. Pretty amazing for a 130,*** mile engine really. I ball honed the cylinders with 320 and I'm going to reuse the pistons with new moly rings

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[496BBC]

Talking with Chris Straub at Straub Technologies he grinds a custom cam that will bring you to around 350HP and 520 TQ with factory FI.

I've got a 7400 that I'm converting to CNP and the Straub Tech cam upgrade for my Z71 K1500

Neal

 

[Christian Steffen]

Would you happen to know the specs on that cam? Is that on the stock ecm tune or custom tune? I've haven't personally seen one on a dyno but a lot of people say a ecm tune alone is worth about 50 hp. It is worth noting that the injectors will probably run out of flow above 350 hp, so if you were going through the work of a cam swap it'd be worth upgrading injectors and having the ecm tuned appropriately.

 

[Jrgunn5150]

Talking with Chris Straub at Straub Technologies he grinds a custom cam that will bring you to around 350HP and 520 TQ with factory FI.

I've got a 7400 that I'm converting to CNP and the Straub Tech cam upgrade for my Z71 K1500

Neal

I've seen the same thing, and I have to say, I'm a bit skeptical of that lol.