what if I didn't match the ports??

-
dodgefreak8

dodgefreak8

Well-Known Member
Joined
Nov 27, 2007
Messages
168
Reaction score
124
I bought a used intake manifold for my 318 build and it had been gasket matched. well long story short after looking at my 302 heads and seeing the HUGE push rod holes I decided to not try and match the ports. Now I am wondering what this will do to my drivability. This is just a daily driver motor so I'm not looking to squeeze every ounce of hp out of it. I just want to know if it hurts the way it's going to run. thanks
 
Is the Intake bigger or is the Head Bigger. A miss match where the head is bigger than intake is not to bad. But the other way around. With the intake is bigger makes a leg the air can hit when it is going in the the head. This will disturbe flow and rob some HP. But it should not hurt your drivability any.
 
well the intake is bigger than the head. Like I said I'm not to worried about some minor hp loss, I just didn't know if it would make it difficult to tune. thanks for the reply
 
Actually to gasket match the ports you don't need to go way in and take any off the pushrod pinch if you don't want too. You just blend the opening up to the pinch area to smooth out the flow. Taking the pinch down is beneficial also but not necessary. You just have to be careful cause you can go through the casting if you take it down too much. By having the intake matched and not the ports it has a wall to run into and cause turbulence which does cause lost performance. How much is unpredictable. Maybe a little. Maybe allot. Every situation is different.
 
on a mild motor smaller runners help with low end torque. You can jb weld or epoxy the intake runner to the head size with a little artistry. You wont see any difference on a stock motor though. The air will flow just fine but the restricted parts may have a little stale air that may produce a drop or 2 of fuel at idle but not enough to hurt.
 
You must log in or register to reply here.
-

Back
Top