Why do headers, ported heads, and cams show such little gains?
- Thread starter Rambro
- Start date
Bdubbs, how much boost did you make before, what do you make now?
With a PD blower you will not see much of a gain because the blower is controlling the amount of airflow. You will see some second order gains and boost will drop. To get the power gain you have to push the blower faster. So lets say you are running 17psi. Then you add headers and it drops boost by 2 psi. You can then run your blower faster bringing the boost back to 17psi. You should see a decent gain doing this. Keep in mind your blower has to be able to support the airflow required. So with the stock blower you will not be able to over spin it enough to keep up with the airflow demands.
I will be isntalling my 1 3/4 ARH this June. Ill try and make a quick pull with my current set up and then do one after. I am also doing a Tubular K and EGR delete at the same time but that shouldnt effect any power numbers. I know 04Sleeper said we would adjust the tune a bit after I change the headers but i dont think that will be much change. Currently seeing just under 17psi with my current set up.
The CORRECT set of cams will add large amounts of power.
Ported heads offer little for two reasons, one the low lift flow is already excellent on stock heads (especially 03-04 C heads) and secondly because the blower shoves the air through and thus inefficiencies aren't as noticeable. Well ported heads matched with the proper intake and cams can offer a large increase but only on more extreme setups.
Headers offer VERY large gains for the cost, as mentioned above they help with scavenging and thus make the motor more efficient. Most people don't pulley down to put the boost back to the same level and are confused on why they only gained a few hp. However, you've gained hp and lowered the cylinder pressure and strain on the engine or you could simply just pulley down and notice a much larger increase. On NA applications to get the most of them they will require long tubes.
Ported heads offer little for two reasons, one the low lift flow is already excellent on stock heads (especially 03-04 C heads) and secondly because the blower shoves the air through and thus inefficiencies aren't as noticeable. Well ported heads matched with the proper intake and cams can offer a large increase but only on more extreme setups.
Headers offer VERY large gains for the cost, as mentioned above they help with scavenging and thus make the motor more efficient. Most people don't pulley down to put the boost back to the same level and are confused on why they only gained a few hp. However, you've gained hp and lowered the cylinder pressure and strain on the engine or you could simply just pulley down and notice a much larger increase. On NA applications to get the most of them they will require long tubes.
The biggest restriction for the terminator is the blower itself. Think about it...the blower only allows a fixed amount of air into the engine per revolution, the stock motor (heads cams etc) components are not really flow restricted until you get to the high power levels. If I had to do it over I would not worry about cams/heads till 700whp or more.
My setup gained over 120rwhp adding cams, higher compression, and e85 with NO PULLEY CHANGE when I turn up the blower I suspect the gains from cams will be much greater
My setup gained over 120rwhp adding cams, higher compression, and e85 with NO PULLEY CHANGE when I turn up the blower I suspect the gains from cams will be much greater
If you run an 11:1 engine with stock cams, stock 15 year old heads, stock 15 year old valvetrain, and stock exhaust manifolds...you will have the potential to pick up a lot of power in the future with mods.
A set of low 230s cams on the right centerlines, a good valve job, aftermarket valvesprings with the correct closed seat pressure, longtubes, etc...and it will gain significant power.
http://www.modularfords.com/threads/46909-Accufab-Built-Kenne-Bell-962-hp-03-Cobra
A set of low 230s cams on the right centerlines, a good valve job, aftermarket valvesprings with the correct closed seat pressure, longtubes, etc...and it will gain significant power.
http://www.modularfords.com/threads/46909-Accufab-Built-Kenne-Bell-962-hp-03-Cobra
Check, check, check, and check. Steve knows what's up.
The eaton, ported or not, limits the potential of any engine work, short, or longblock.
Go throw that eaton on a 5.8L trinity mill. Won't make much over 525whp. Same story on a 5.4, etc. (fab upper intake manifold etc, just a hypothetical).
The eaton was great at taking a 320hp engine to 425hp, with lots of torque. For the times, it was explosive power.
Heads and cams matter. Look at a fbo 5.0 coyote road runner vs a fbo 5.0 stroker modular.
350whp (tops) vs 475whp.
Go throw that eaton on a 5.8L trinity mill. Won't make much over 525whp. Same story on a 5.4, etc. (fab upper intake manifold etc, just a hypothetical).
The eaton was great at taking a 320hp engine to 425hp, with lots of torque. For the times, it was explosive power.
Heads and cams matter. Look at a fbo 5.0 coyote road runner vs a fbo 5.0 stroker modular.
350whp (tops) vs 475whp.
Just FYI i ran by a shop near my house(suburu shop) hopped on their AWD dyno for a couple pulls. After i do my headers in two weeks ill go by again. No other changes being made.
Right on very interested in the results. After constantly hearing my buddies car with long tubes I'm thinking it might be worth it for the sound alone.
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