L29 rebuild - give me ideas

andy396

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Retarding the cam put the peak torque lower in the rpm band. Being a truck application I’m guessing it was their solution for making an engine with nice low end grunt.
 

Schurkey

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Retarding the cam put the peak torque lower in the rpm band. Being a truck application I’m guessing it was their solution for making an engine with nice low end grunt.
Advancing the cam drops the RPM of peak power. Retarding the cam raises the RPM of peak power.

I'm thinking that retarded cam timing is/was done for emissions-control reasons, not for "power".
 

Christian Steffen

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Do you know whats up with the stock cam being 6 degrees retarded? I've asked and asked about it but no one can give me a decent answer. I have no idea what that would achieve or if its something I should be calculating into a tune with a new cam.

I have no idea what their goal was with the cam retard.. all it should do is move peak torque up in the band. As far as the new tune goes, it just affects airflow and timing, nothing else to really consider.
 

L31MaxExpress

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I have no idea what their goal was with the cam retard.. all it should do is move peak torque up in the band. As far as the new tune goes, it just affects airflow and timing, nothing else to really consider.
Cleaner emissions and less dynamic compression to keep it from knocking on 87 octane towing on a long uphill pull.
 

Philip Parker

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Just an update on this build - here's where everything landed:

I had to ditch the AFR heads due to a manufacturing issue and went instead with a pair of Brodix Race Right oval ports. Everything is put back together and the truck is running great. Just to recap the parts lit:

Brodix Heads 270cc (I think)
247/282 - .510 on both sides - hydraulic Roller
Melling Lifters
Comp Magnum XD rockers
PAC 175-375 Dual Valve Springs
Comp .135 wall push rods
Melling high volume oil pump
Milodon High volume water pump
180 degree thermostat
PSC Steering pump
redhead steering gear
Full disc conversion on rear brakes
Updated steering cooler
Stock manifolds that were ceramic coated
Stock intake and injection
ECU tune for cam and heads

A Dozen new cooler lines, all new gaskets (be careful on head gaskets and make sure you get a Gen VI compatible one), no more leaks.

Impressions so far:

After getting my timing sorted the truck runs very good. It runs quieter than it did before with the non adjustable valve train. Getting the preload on brand new lifters took a lot of work and eventually they quieted down as well. We're at 6000 feet here in Colorado but the engine pulls much better than it did before, most noticeably around the 2500 rpm range. Idle has a tiny lump to it due to the cam but I have zero DTCs with the tune I got from Try Brown at Howell. Fuel trims and other compensations are like 2% - kind of impressive he was able to get it so close.

I had to get low profile poly locks for the rockers to get the stock vlave covers to clear, as well as use 1/2" thick cork gaskets. Everything clears and nothing leaks.

I also installed a new airlift 5000lb bag kit and a Redarc Proportional Brake Controller, which is a sweet piece of kit.

The biggest surprise is how cool this thing runs now with the pump and thermostat. It was 85 degrees yesterday and I drove the truck around town for an hour, stop and go traffic. It never crept above 180 at all. No spikes at stop lights. The oil pressure when fully hot at idle is 20 psi. 40 psi while driving hot. 60 psi on cold startup.

Next items are cosmetic or body related, but in general things turned out great. Thanks for everyone's suggestions.

Philip
 

Christian Steffen

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Just an update on this build - here's where everything landed:

I had to ditch the AFR heads due to a manufacturing issue and went instead with a pair of Brodix Race Right oval ports. Everything is put back together and the truck is running great. Just to recap the parts lit:

Brodix Heads 270cc (I think)
247/282 - .510 on both sides - hydraulic Roller
Melling Lifters
Comp Magnum XD rockers
PAC 175-375 Dual Valve Springs
Comp .135 wall push rods
Melling high volume oil pump
Milodon High volume water pump
180 degree thermostat
PSC Steering pump
redhead steering gear
Full disc conversion on rear brakes
Updated steering cooler
Stock manifolds that were ceramic coated
Stock intake and injection
ECU tune for cam and heads

A Dozen new cooler lines, all new gaskets (be careful on head gaskets and make sure you get a Gen VI compatible one), no more leaks.

Impressions so far:

After getting my timing sorted the truck runs very good. It runs quieter than it did before with the non adjustable valve train. Getting the preload on brand new lifters took a lot of work and eventually they quieted down as well. We're at 6000 feet here in Colorado but the engine pulls much better than it did before, most noticeably around the 2500 rpm range. Idle has a tiny lump to it due to the cam but I have zero DTCs with the tune I got from Try Brown at Howell. Fuel trims and other compensations are like 2% - kind of impressive he was able to get it so close.

I had to get low profile poly locks for the rockers to get the stock vlave covers to clear, as well as use 1/2" thick cork gaskets. Everything clears and nothing leaks.

I also installed a new airlift 5000lb bag kit and a Redarc Proportional Brake Controller, which is a sweet piece of kit.

The biggest surprise is how cool this thing runs now with the pump and thermostat. It was 85 degrees yesterday and I drove the truck around town for an hour, stop and go traffic. It never crept above 180 at all. No spikes at stop lights. The oil pressure when fully hot at idle is 20 psi. 40 psi while driving hot. 60 psi on cold startup.

Next items are cosmetic or body related, but in general things turned out great. Thanks for everyone's suggestions.

Philip

Hell yeah that's good to hear, sounds like it turned out good! Hopefully you were able to return the AFR heads, what was wrong with them?

Do you have a wideband o2 sensor? If not I would recommend one, just to keep an eye on things.
 

L31MaxExpress

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Just an update on this build - here's where everything landed:

I had to ditch the AFR heads due to a manufacturing issue and went instead with a pair of Brodix Race Right oval ports. Everything is put back together and the truck is running great. Just to recap the parts lit:

Brodix Heads 270cc (I think)
247/282 - .510 on both sides - hydraulic Roller
Melling Lifters
Comp Magnum XD rockers
PAC 175-375 Dual Valve Springs
Comp .135 wall push rods
Melling high volume oil pump
Milodon High volume water pump
180 degree thermostat
PSC Steering pump
redhead steering gear
Full disc conversion on rear brakes
Updated steering cooler
Stock manifolds that were ceramic coated
Stock intake and injection
ECU tune for cam and heads

A Dozen new cooler lines, all new gaskets (be careful on head gaskets and make sure you get a Gen VI compatible one), no more leaks.

Impressions so far:

After getting my timing sorted the truck runs very good. It runs quieter than it did before with the non adjustable valve train. Getting the preload on brand new lifters took a lot of work and eventually they quieted down as well. We're at 6000 feet here in Colorado but the engine pulls much better than it did before, most noticeably around the 2500 rpm range. Idle has a tiny lump to it due to the cam but I have zero DTCs with the tune I got from Try Brown at Howell. Fuel trims and other compensations are like 2% - kind of impressive he was able to get it so close.

I had to get low profile poly locks for the rockers to get the stock vlave covers to clear, as well as use 1/2" thick cork gaskets. Everything clears and nothing leaks.

I also installed a new airlift 5000lb bag kit and a Redarc Proportional Brake Controller, which is a sweet piece of kit.

The biggest surprise is how cool this thing runs now with the pump and thermostat. It was 85 degrees yesterday and I drove the truck around town for an hour, stop and go traffic. It never crept above 180 at all. No spikes at stop lights. The oil pressure when fully hot at idle is 20 psi. 40 psi while driving hot. 60 psi on cold startup.

Next items are cosmetic or body related, but in general things turned out great. Thanks for everyone's suggestions.

Philip

How do you like the Redhead steering box? Considering one for my Express van. Have heard nothing but good things about them. Both boxes I have currently that fit the van are loose on the pitman arm end. The one on my 97 barely over 100K and loose as a goose.
 
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