L29 rebuild - give me ideas

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

yevgenievich

I'm Awesome
Joined
Jan 21, 2021
Messages
934
Reaction score
1,505
Location
TX
I am going the tall deck 488 route for l29 replacement. Might spend the money on the better heads, but l29 style heads are decent. Supposed to have been dyno at 430hp, 530ftlb from 488 variation. Stock intake manifold might put those numbers down some.

Anybody interested in l29 style oval heads that are new with hardened seats to handle natural gas applications?


And actually turned out that i don't really need a replacement any time soon. So will be slowly gathering parts. Current motor still decent with 140psi compression and 30psi hot idle oil pressure. 230k miles
 
Last edited:

yevgenievich

I'm Awesome
Joined
Jan 21, 2021
Messages
934
Reaction score
1,505
Location
TX
8.0 was cheapest new bock and internals combo that I could find. Has 58x 4x setup to run with newer ecu. Will be changing to 24x 1x setup for 411. LS firing order. Basically 8.1l except based on standard tall deck, so it would accept any standard bbc head
You must be registered for see images attach
 

Christian Steffen

I'm Awesome
Joined
May 31, 2016
Messages
1,173
Reaction score
431
Location
Green River, WY
8.0 was cheapest new bock and internals combo that I could find. Has 58x 4x setup to run with newer ecu. Will be changing to 24x 1x setup for 411. LS firing order. Basically 8.1l except based on standard tall deck, so it would accept any standard bbc head
You must be registered for see images attach

That's pretty awesome. Goes for about $6k? Not a bad price!
 

Aparke4

I'm Awesome
Joined
Nov 4, 2019
Messages
202
Reaction score
184
Location
CA
Any thoughts to rebuilding the 454 (low friction build/ non stroke/ cam and roller rockers) and going with a STS universal remote turbo? Or adding a low boost solution like LT did?

xc_hide_links_from_guests_guests_error_hide_media
 

Schurkey

Supporting Member
Supporting Member
Joined
Jan 14, 2018
Messages
10,970
Reaction score
13,755
Location
The Seasonally Frozen Wastelands
l29 style heads are decent.
I gave up on L29 heads on my boat. Took off old-style round port heads, thought the oval-port L29s were going to be an upgrade.

Hardly noticed a difference. Engine gained about 150--200 rpm; from 5K to about 5150--5200 rpm. That IS an improvement, but less than I was hoping for considering the old heads had severely wiped-out valves.

Anybody interested in l29 style oval heads that are new with hardened seats to handle natural gas applications?
Don't all L29 heads have valve seat inserts on intake and exhaust? My eBay L29s that went onto the boat did.
 

yevgenievich

I'm Awesome
Joined
Jan 21, 2021
Messages
934
Reaction score
1,505
Location
TX
I gave up on L29 heads on my boat. Took off old-style round port heads, thought the oval-port L29s were going to be an upgrade.

Hardly noticed a difference. Engine gained about 150--200 rpm; from 5K to about 5150--5200 rpm. That IS an improvement, but less than I was hoping for considering the old heads had severely wiped-out valves.


Don't all L29 heads have valve seat inserts on intake and exhaust? My eBay L29s that went onto the boat did.
I believe l29's supposed to be comparable to older oval port heads but with 99c chamber.
This ones supposed to have better seats than standard l29's. Appear to have better intake runners as well(i think). And adjustable valve train.
You must be registered for see images attach
 
Last edited:

Christian Steffen

I'm Awesome
Joined
May 31, 2016
Messages
1,173
Reaction score
431
Location
Green River, WY
Any thoughts to rebuilding the 454 (low friction build/ non stroke/ cam and roller rockers) and going with a STS universal remote turbo? Or adding a low boost solution like LT did?

xc_hide_links_from_guests_guests_error_hide_media

LTs build has been fun to watch lol The fit would be tight but personally i would go with an upfront turbo if i were to do it again. Piping the cold side up on a rear mount is kinda a pain, and then you need an oil system. I would also just build it rather than buy a universal kit. The stock L29 bottom end with some ring gap will hold plenty of boost, Richard Holdener has gone to about 1000 hp so far on his big bang motor. The L29 heads wouldn't like that though.

So far I've run my truck up to about 5-6 psi and it absolutely rips, honestly anything into positive pressure feels great. I need more fuel system before i think about going up in power more.
 
Top