Ok, that's pretty on par with his claim. I'd just like to see the evidence, because I've been in the game a while and to this point, I haven't. So, if you have a link handy, please send it my way. I'd like to know. Swapping intakes is an easy 15 rwhp on an otherwise stock motor. What is opening up the exhaust port worth?
Challenge accepted. When was the last time you looked at an e7 exhaust port ?...
I searched and searched online....just found a bunch of people that said it in other forums. This is something I've personally seen proven at the track. These tricks come from the old school guys that new how to squeeze power out of these engines. You'd have to find it in an older horsepower or engine building magazine.
Because of emissions Ford choked the exhaust side of the heads....you can look at them and tell. Maybe they did that so the internal egr valve would have enough flow.
Think about it like common sense...
You have air and fuel coming into the chamber through larger openings and larger valves. Combustions happens and heat expands that mixture enough to force the piston down. That blown up mass of gas then has to exit through a smaller valve and out through a smaller hole....with a ridge and a bump in its path.
Why do you think aftermarket camshafts increase lift and duration on the exhaust side ? That's what set these " new " camshafts on a bar above alphabet cams. Ya know how they figured that out ?....it was the uses putting 1.7 rockers on the exhaust side increasing lift. Ya know why it worked ?....because the exhaust valve had to open more to even the flow out of the head.
I had fast ported e7 heads....the exhaust ports were matched to my
bbk headers and had 1.6 valves. Those heads ran circles around a bunch of guys. I don't have dyno sheets or time slips to prove it....so I'll leave that alone....but I didn't have an ugly 10 point cage in my convertible for nothing.
Wish I could've found some verifiable info on the web. These cars have been modified since way before the internet.
Its like using an escort alternator pulley to spin a 130a alternator faster to get away from the lights flashing at idle with a sound system. It's like using truck lower intakes and sheet metal uppers grafted to a chopped up truck intake ( how trickflow started ). There are a bunch of small things that have been proven to make power.
I'm not saying the intake isn't restrictive....just the bottle neck is at the exhaust side if the head. With a good camshaft it can help by opening that exhaust valve more....at that point the intake will start to show its weaknesses. We all know that power is a combination of things.
I guarantee that if I had an all stock fox...with only the exhaust side of the head ported, with a bigger valve, I'd pull away from an all stock car. If you put a decent intake on an all stock car- an all stock car will run right with it.
I rest my case....
