One step often overlooked is found while people are doing head work. If the casts are good and you send them to a machine shop to tell you so, then at least have the valves and seats ground or replaced and have the heads polished. Polising is very productive as it allows more air into the cylider this creating more horse power. This can be added to your bill as a small amount and some people will at least smooth the high edges down and clean up all the casing errors. Sometimes dropping a $20 down on the hand of the shop employee will get things rolling.....Ha Ha

If one does not have the motor broke down then larger rockers might be your choise. OEM rockers are at 1.6:1 ratio and an upgrade to a 1.7:1 Basiclly this is just like camshafting your motor. This provides longer opening of the valves for a longer duration. This is about a 30-50 hp bolt on and takes about 1 1/2 hours. 1.6:1 is only about 8 hp. Cost between $350 to $750 depending on the maker. The part numbers are as follows for the 5.9L/5.2L

Mopar
P5007404 1.7 ratio roller rocker
P5249800 1.6 ratio roller rocker

The valve OEM covers can be reused if you take out the baffles on the stock covers or adjust them out of the way. If you want the look then you can buy MP valve covers because the look better and are a bolt on.

If you buy the Crower rockers, they are stainless, not aluminum like MOPAR, much better longevity. Stainless doesn't "harden" and fail down the road. To properly (and easily) adjust your new rockers do it this way. Use the exhaust opening/intake closing method. This is the EOIC method. Turn the motor until the exhaust valve is just opening. Adjust intake rocker 3/4 turn, tighten. Turn motor until the intake valve is 1/2 to 3/4 closed, adjust exhaust rocker 3/4 turn, tighten. Do all rockers this way, adjust baffle, assemble motor, enjoy. Roller lifters need .045 to .060 preload. You get the proper preload with 3/4 turn, not the 1/2 everyone tells you to use. Remember to set each one in bolt sequence just like torque order.

 

I see we have a hot thread going
I have Questions for the inexperienced.
Okay so should One go with stamp style rockers or rollers?
What is better solid, Hydraulic, or roller lifters?
Does it matter what pushrods I get?
Will any of the mentioned above change after I bore my cylinders????
Hey what about that distributor I heard it doesn't ever have to be changed, just the gear on it.
Is this a good time to change the infamous Pentium gasket?
What can I do when I step up in cam size and lose vacuum presure?
How about the camshaft sensor.
Is there any diff between timing belts and gear drives?
Is copper a good material for my head gasket?
Are there any other sensors I need to replace when I take this engine rebuild in mind.

I would be nice to get info from the Daks and Rams...

 

Holly **** DR0318!

Roller rockers are the best. You want the ones that are fixed and non adjustable.

If you cam a motor there is no need for larger rockers. It's basiclly doing the same thing. Port and polishing heads allow more fuel air mixture into the cylinder so as doing the same thing as a cam or larger rockers. The reason I put this up was to include the larger roller rockers on heads that are installed already and for people that do not want to pull the heads. This is a good recourse.

The better thicker push rods would be A LOT better than the stockers on the 1.7:1 upgrade.

Roller lifters. If you put rollers in stay with them.

I would install the Fel-Pro PermaTorque Severe Duty head gaskets.

Boreing cylinders will allow more fuel air mixture thus creating more power. Be careful when camming a boared engine because there is already going to be more compression thus creating more potential for the need to use higher octane. If I were you I would port and polish the heads then if needed install the 1.7:1 rockers. This is what I did and I run 87 octane. Also be careful on boreing cylinders as the walls become thinner and prone you to overheating. 20 to 30 over is a good bore for the motor without creating this problem.

Vacuum should not be changed on rebuild.

Do the gear on the distributor when rebuilding. This can also be done at any time by pulling it out.

Camshaft sensor should be fine unless it's going out.

Pentium gasket should be replaced at this time. Or a better upgrade would be the M1 intake. Match that up with a bored throttle body from Dan at www.thefastman.com

I would go with timming chains on 4X4's not to mention I don't think they can have belts due to oil.

Sensors should be fine.

 

If I were starting at zero with a 5.9L or a 5.2L I would build it this way for power and longegivity.

Have the block bored out no more than 30 over if you can get away with it. Sometimes ya can't. Have the shop install crank, pistons, and camshaft (Short Block). Have your heads machined and port and polish or step up to Edelbrock Performer heads. http://www.edelbrock.com/automotive_...r_sb_rpm.shtml

Caution: They are not emission ready for Performer heads.

I would install a OEM cam with this setup because with the heads P&P and the cylinders bored you are already knocking on the door of octane requirements and emissions not to mention over use of fuel mpg's. You can always install bigger lifters and get the same effect as a cam later if wanted. Even if you don't port the heads at least polish them up like I said in the other post in this thread.

Next install the OEM intake. The reason for this and not the M1 is fuel saving. Install a bored throttle body from Dan at www.thefastman.com (don't forget to tell him your from the DF). Install a true cold air intake or ram air. Install a K&N filter.

You will want a power house ignition so take a look here at what I did:
Part Numbers for 5.9 Performance Ignition

 

Hydra, I think you meant to say that one can install bigger rockers for more cam action as you stated earlier.

Also I haven't really been around here much but I hang around the classic Pontiac forums where they talk alot more about performance builds. One thing I have learned there is that a stock smallish cam combined with more compression can create more detonation issues. A bigger cam cam bleeds off this excess pressure to reduce the chance of detonation. I'm not sure how this would apply to the compression your recommended combo would be looking at but I know it helps for combo's with iron heads up to around 10:1 and aluminum to 10.5:1.

 

I posted this how I would build a motor for longevity and fuel mpg's as well as keeping the octane requirements down so that less money is spent at the pump but more power to the wheels. This is only my opinion.

All I'm saying on the subject of cam's is exactly that. If you have too much fuel & air combo going in detonation can happen requiring higher octane requirments which is not saving at the pump but rather building a performance machine. By boreing the cylinders and head this will get ya up to about 10:1 from the 9:1 and maybe upwards slightly.

1.7:1 rockers can be installed later if wanted or needed but I BET you will ping.

Lastly, boreing the motor close to OEM and adding P&P heads should run 87 octane. Pontiac run OEM more compression. I don't understand how putting in a bigger cam can fix detonation because it adds fuel/air and more compression thus creating MORE ping.

Where is the motor suppost to bleed from in a sealed combustion chamber?

 

My pontiac 400 runs 8.0:1 compression and I had to use a smaller cam due to my low compression.

Bigger camshafts reduce cylinder pressures at lower rpm's compared to stock cams because of the duration on the intake side. Technically at lower rpm's the intake valve stays open too long and keeps the max amount of air/fuel from going in. Thats why vacuum is lower with bigger cams because the valve closes too late.

Now I know this goes totally against economy but it is known that too small cams in high compression engines can cause detonation.

Now what would be nice to see is if Rhodes lifters makes their bleed down style for the roller lifters in these engines. Then you can run a big cam with moderate compression but have it idle close to stock and get good mileage but when the rpm's get up, the lifters pump up and take full advantage of the cam.

 

Also I see that you live in salt lake city. Have you had your D down at sea level? I bet you would be needing higher octane in it because of the higher air pressure at lower altitudes. 10:1 is somewhat high to be running 87 octane. No cars come from the factory with compression that high and only using 87 octane. Cars at lower altitudes would be blowing rods through the pan.

 

OEM is 9:1 and with the mods I currenty have that is were I'm guessing. Now at sea level this might be true, IDK. That does bring up a great point tho.

What is the mathematical equation for compression by lbs of compression in the motor?

 

There is no way to accurately calculate compression by just knowing the cranking compression psi. There are 2 types of compression to be calculated. Static and Dynamic compression.

Static is you calculate the swept volume of the piston and see how much it is compressed into the head.

That is basically the area of the bore multiplied by the stroke to get the swept volume. Then you have to calculate the combustion space which is more complicated.

You have to get the exact volume of the heads, that means have them checked specifially dont trust the published specs. Calculate the quench area volume, that is the volume that occupies the space above the piston at TDC to the deck height. You need to calculate the volume that the head gasket adds which is find the compressed thickness and find the volume of that. Then get the volume of the valve reliefs or dish or dome on the piston. Add all these up together.( if the pistons have a dome, subtract the volume because the domes take away combustion space.)

Now divide the swept volume by the combustion space. thats the Static compression.


Second type is Dynamic. This is the compression of how the camshaft profile effects the compression. I do not know enough about this subject to explain it confidently and I do not want to post wrong info here.