Newbie that needs HELP Please

Hi,
I a newbie that is desperate for some expert advice. I have 2 questions.

1st ? I have a 86 5.0 HO that I'm rebuilding and installing in an 84 F150 for my 16 yr. old. This HO has the flat top pistons with E6 heads. If I were to replace the E6's with either GT40 or E7 heads will I have valve to piston clearence issues.

? #2. If theres not and clearence issue, how big of a cam before it becomes an issue.

Thanks
Phil

Yes think you will find the valves will hit the flat tops.
I know some how have rented a relief cuttter and cut valve reliefs in the flat tops.

E7's have the same size valve and would work. The old Ford motorsport catalogs said 40's would not. If it is a truck the HO cam may be just about right as a performance cam.

Thanks guys,

IWANTMORE, the motor came out of a 86 Mustang, I bought it cause it was a roller motor, I didnt do any research before I bought it so now I'm really learning alot about Ford engines!!!!!!!!

Do I stay with the OEM cam or can I go a little bigger.

Also if I go with E7 heads, edelbrock performer, maybe a 650 CFM, stock cam and shorty headers, any guesses how much HP we'll end up with.

1 more ? if I may, are those E6's as bad as everyone claims

Thanks again
Phil

E6 are bad but not that bad, they will be a good choice for high torque/low RPM applications.
The flow numbers are similar to stock E7TEs up to .5" lift, so if you'r building low RPM cruiser you'll be fine.
Like "iwantmore" wrote, valve are same size, but they are heavily shrouded, they have the "heart" shape and not the "D" shape like the E7.
E6TE valves, sit higher in the chamber, if you'll bolte them to a later block with pistons that have valve reliefs, a higher valve lift should be possible or if you'll use with flat top's, you can use a higher lift compared with E7.



Intake:


Exhaust


The E6 are good for low end, better then E7 cause you'll get the max power sooner, the stock specs for the non HO engine (using same E6 but different cam) are 270ft@2000RPM while same engine with E7 has 300ft@3200RPM so its about 10% less but 1,200rpm quicker.

I have same block came out of 86 T bird, this is non HO but except the cam every thing is the same as yours, I have most of the bolt on's like MSD, headers, high performance intake and carb and it is a fun ride, I'm driving daily so the E6 are giving me the advantage over the E7 for the city driving.

Every litle thing I did to this engine was very noticeable, HEI ignition, electric fan, better manifold all had dramatic performance gain.

So about the headers, I disagree, I felt a noticeable change after changing the old manifold to headers, I used a small tube headers (1 1/2 not 1 5/8) to help the low end, and it was good upgrade.

The cam I'm using right now has a lift .477/ .484 and have no problems.

So, I think that it is all up to you and what the engine meant to do, if you want a street machine to smoke every one get AFR heads and notch the pistons, if you are looking for a nice engine to drive get reasonable fuel economy and strong and perky through the low end, you'll be fine with your engine, just try to get as much as bolt on's (like I mentioned) as you can, and a 3.55 - 3.8 gear ratio will work nice too....