Intake Gasket

[Wild Blue 32]

BY rules we are required to run the oval port head along with the oval port intake. I read somewhere that the oval port intake ports are too big for a 2.3. And by filling the bottom of the intake port in making it smaller would increase horsepower. This is illegal according to our rules. Would running a d port gasket on an oval port head help? It wouldn't make the port smaller just the opening into the head which should increase the velocity of the airflow. What are some thoughts on this? Has anyone tried it?

[car62]

i have no idea why you feel the oval ports are too big...they seemed to do fine in a street car,so wouldnt it be better at higher rpm in a racecar?

[dave41]

gasket would create a wall which would cause a tumble. not good to interfere with flow

[themotorshop]

the oval port head wasnt found to be to big,it was found that fuel would puddle on the bottom of the runner and cause bad gas milage and emision problems,as long as you can keep the rpms up that shouldnt be a problem with a race motor,what you could do is build up the bottom of the runner properly and use a D-port intake to increase low speed velocity and quicker rpms,or you can also build up the oval port intake to make the transition into the head port blend

[return to dirt]

why are the d-port carb intakes illegal? they used a carb from the factory. they aren't a reworked efi intake. other than the casting number they look the same as an oval port intake from above.

olin

[themotorshop]

different tracks, different classes,you would have to read the rules for the engine and cylinder head section from each, to see were they were going with it, and possibly why

[Old Rob]

Do not use the D port gasket on oval port manifolds. You will lose power thru out the rpm range. The ports are not too small, remember they were designed for a street engine power from idle to approx 5500 rpm. You can use a piece of metal to block the water to the manifold, helping to keep it cooler for a denser charge. Also LPG 2.3L intake gasket comes with a blocking plate. They were used a industial engine, pricey thou.

[Wild Blue 32]

I burn E85. Would I still want to block the water passage?

[TM 44]

2.3 intake gasket: Fel-Pro part number MS91806 This gasket is for a D-port head and has the water passage blocked off. Lay an oval port gasket on it, mark the holes and use a drimmel tool to enlarge the holes. Works great and the same inexpensive cost.

[TM 44]

MS91806 $10.99 Advance Auto price Good picture of it too.