my notch vs. 96 cobra

[strtrcr50]

Yeah cause its worth giving up some low end torque so you can have no more power up top..... wait, that aint right.

I remember when MMFF was doing their cobra buildup. I believe the project name was superfly. I still wonder what they thought they were accomplishing with their imrc deletes. Maybe 3-5 hp up top because the butterflies didn't obstruct hp?

 

[LaserSVT]

I remember when MMFF was doing their cobra buildup. I believe the project name was superfly. I still wonder what they thought they were accomplishing with their imrc deletes. Maybe 3-5 hp up top because the butterflies didn't obstruct hp?

I guess if you were building a race car that spends 90% of its time above 4500 then it may help but it hurts it as a street car so much and even as a road corse car because you would have to shift more often.

 

[rock4451]

do all 4vs have the IMRC, even the termi's?

 

[bentley429]

Cobra, does it have gears? If so it will be worse.

 

[Gearbanger 101]

do all 4vs have the IMRC, even the termi's?

No, the later 4-valve engines (99-up) had a revised head design that promoted more torque down low. The '99 and '01 heads got the "tumble port" design, which boosted torque down low, but as a result gave up a little on the top end compared to the earlier "B" castings. It wasn't until they revised them again on the '03-'04 Cobra, Mach 1, Marauder that they were able to find a nice balance of both.

The IMRC plates and "B" heads were available on early 4-Valve Cobra's, Lincoln Mark VIII's and Lincoln Continentals.

I can't remember off hand where the SUV heads fell into the eqaison...but they were later castings as well.

Some good 4V head info here. 4v head info - Mod Motor Tech Forums

 

[rock4451]

no the cobra doesn't have gears. i'm goin to the track here relatively soon...if i line one up i'll tell ya how it goes...