5.7L Towing Upgrades (yes, another thread)

[Trenton]

Been running aluminum roller rockers for years on street and towing engines. Have not had one problem. Have had more problems with factory rockers. With factory rockers I would not go over about 100 lbs seat pressure, 250 open or more than 0.470 lift. Otherwise they will quickly wear out the rocker ball area and break apart. I never have bought a roller rocker arm that does not have a sealed trunion bearing.

The LS6 GM Performance Valve Springs are rated at 95 lb seat pressure, 295 lb open pressure, have a .550" max lift before coil bind, but the cam you suggested has a max lift of .487". What is the most cost effective option for rocker arms? Sounds like I shouldn't use the factory arms, but I'm not sure if 1.6 roller rockers are worth it.

 

[Supercharged111]

The LS6 GM Performance Valve Springs are rated at 95 lb seat pressure, 295 lb open pressure, have a .550" max lift before coil bind, but the cam you suggested has a max lift of .487". What is the most cost effective option for rocker arms? Sounds like I shouldn't use the factory arms, but I'm not sure if 1.6 roller rockers are worth it.

Those spring ratings are at LS installed height, not where they end up in an L31. You'll find higher seat pressure and less lift tolerance on an L31 than an LS.

 

[Hipster]

The reason for a gooseneck is because I prefer the way they pull and handle weight. My high school shop built one and it was so much easier to maneuver. I liked the way they pulled on the highway versus a bumper pull trailer. Pulling the weight through the mountains in a 22 year old truck, just gives me piece of mind. Eventually, I want to get a diesel and turn my current '98 into an off road rig and haul it around, but that's also a dream.

It already sucks on gas, I can't imagine being any worse, lol. My daily driver gets a whole lot better in town than the '98 will EVER get on the highway unloaded, and it's what I normally drive. You don't do these things if you're worried about MPG.

I figured there was some other plan was just curious. I know I see a difference on my junk with different weights.

 

[Hipster]

With a wimpy truck cam I just don't see an issue with a good aluminum full roller rocker. I went with the Comp Pro Magnums on my 1500 out of pure paranoia and they are dead silent. I do agree with the bumper pull sentiment. Yes a goose pulls nicer in some ways, but when you're under 10k it just seems like you're splitting hairs.

I'd error on the side of paranoia as well. And I still am. The broken ones I pulled off were undoubtedly on more serious engines.

 

[badco]

Those rockers won't help you at all. Go with the full roller if you get rockers. The main friction reduction is the pivot point not the tip. The rollers also keep better geometry than the sliding of the factory style pivot balls.

The tip is the friction point. Good Roller tip vs full roller is 3hp or less different on dyno.
Test was done on a aluminum headed hyd roller mild street engine between the 1.52 comp roller tips vs the comp pro magnum xp full roller

 

[L31MaxExpress]

The tip is the friction point. Good Roller tip vs full roller is 3hp or less different on dyno.
Test was done on a aluminum headed hyd roller mild street engine between the 1.52 comp roller tips vs the comp pro magnum xp full roller

The tip is a small percentage of the friction. The fulcrum is most of the friction on a rocker arm. As such GM engineers equipped the LS and later 4.3s with roller fulcrums and fixed tips. I have personally run roller tips and they are a waste of time and money compared to full roller. Had experience with a set of Comp 1.52 roller tips on an engine I messed with that was built by someone else. The LT4 Hotcam chewed up the rocker balls and pivot points in short order. Swapped to a set of full roller 1.6s and it has been problem free for my friend that owns it.

I run 7/16" stud wide body aluminum Scropion 1.7s on my 383 with hardened pushrods and guideplates.

 

[Supercharged111]

The roller tips help reduce the side load on the valve stem and guidess, which increases with lift.

 

[94K3500PROJECT]

What rpm are you running in most?
That’s the thing with a “towing” build: the power you want is from idle to 4k rpm.
A cam can boost that some as long as your careful.
Best way is a stroker bottom end.

My CCLB K3500 is going to get a Vortec head 406 with TPI intake setup. If it runs out of breath at 4500rpm I’m ok with that

 

[94K3500PROJECT]

The other thing I’ll say is that the 2.48 first in the 4l80 doesn’t do any favors pulling from a stop.
A lower first gear set is available but that’s gonna be $$!

A lower rear gear could help too but if you have 4.10’s already a 4.56 swap may be too much depending on tire size

 

[Trenton]

The other thing I’ll say is that the 2.48 first in the 4l80 doesn’t do any favors pulling from a stop.
A lower first gear set is available but that’s gonna be $$!

A lower rear gear could help too but if you have 4.10’s already a 4.56 swap may be too much depending on tire size

A 4.56 gear swap would be beneficial, especially with the 285/70R17 (~33s), if I had the time. My truck is 4x4, but with the lift kit cross member in the way of the front diff, taking it apart to change them, and the labor to properly install 4.56 gears in the rear 10.5 axle, it would be too much work in the 2 weeks or so I'll have when I go home.

Going to 32.8" tires, I would need a ~4.39 gear ratio to equal the 4.10s that came stock. Obviously, that doesn't exist, so a 4.56 gear would definitely be beneficial, but not as easy as the engine upgrades.