J.R. said:
jfor441 said:
J.R. said:
Well now I wanna know why he doesn't run that combo on his own motor? Kinda fishy to me. I'm gonna ask him I guess, since I don't think he's registered here.
The setup I posted above is something have developed for NA folks.
I know, but his own car is N/A, that combo they are hocking seems a little extreme for a DD, even though i recall them billing it as such.
I'm not bashing him, he's a helpful guy, I'm just questioning is all.
He specifies that the build is for racing.
"Something that say, a bracket racer or a modular muscle racer would be interested in."
He doesn't even mention it as a DD, but he did mention you could drive it to the track if you take out timing and don't get on it.
Your use of your car needs to be chosen, or you have to decide how much performance in each area you are willing to give up. How much road manners are you willing to sacrifice for a car that does pretty good on the track but not as good as it could?
For the road you need an engine that can fill the cylinders efficiently at low and mid RPM. To do this you need to maintain air flow
velocity. This is what gives you torque to pull out into traffic and a good idle with vacuum to run vacuum actuated accessories, if your car uses them. In a high RPM race engine you need to be able to flow a
volume of air in a short amount of time in order to fill the cylinders. This requires a larger intake flow, in cross section, to be able to move a greater volume of air in a shorter amount of time. This is where top end power comes from. Low RPM torque is lost as the velocity needed cannot be achieved. The flow path is not efficient at low RPM.
Think of it as when you buy a Pepsi from a fast food restaurant. Some places have large diameter straws take forever for you to get a mouthful of pop while you suck all the air out of it. Other straws are narrow and seem to rocket the liquid to the back of your throat, almost choking you. Same thing with your intake manifold and heads, N/A.
These are the physics you have to account for when choosing how you are going to build your engine. That's why there is no engine combo for low end torque and high end HP. There are physics that cannot be discounted.
Another choice you may have is getting your intake extrude honed. This will open up the runners and still maintain the geometry of the runners. Just a thought.
Steve