HO Conversion Heads

[Grand1]

So Im close to the conversion(down to head selection)....just kinda stumped on the heads.

I know I could get the E7 heads....but what if I went to the Thumper E7s or the GT40 heads; are these choices past "HO"????
Anything additional one would nead to do...... if getting different heads?

I already have dual exhaust, and a higher stall convertor...........the missing link cometh.

[gadget73]

both are an upgrade beyond stock HO parts
you may have problems with it running too lean on speed density though since they move more air. Or maybe it'll work.

[Grand1]

Also, being ignorant of buying heads, what should I look for....as far as worth and quality?

Heres what I have been looking at:

http://chicago.craigslist.org/sox/pts/3751370368.html

http://www.ebay.com/itm/FORD-TRUCK-V...a58705&vxp=mtr

[Grand1]

both are an upgrade beyond stock HO parts
you may have problems with it running too lean on speed density though since they move more air. Or maybe it'll work.

Cool, thanks man.....want to get rid of any maybees......so E7 it is or E7TE(?)

[mcninetyone]

I'm using GT40's with speed density and no problems, the car runs great!!

[pantera77]

Also remember with the gt40p's you'll need to run either 90 Town Car manifolds, or special headers.

[gadget73]

I'm using GT40's with speed density and no problems, the car runs great!!

see, and I ran ported E7 (E7 = E7TE, same thing) heads and it ran so lean that it sounded like a can of marbles under the hood all the time and on the dyno it showed a very lean air fuel ratio. I'd like to figure out the magic juju that makes some work and some not work.

[tjc78]

see, and I ran ported E7 (E7 = E7TE, same thing) heads and it ran so lean that it sounded like a can of marbles under the hood all the time and on the dyno it showed a very lean air fuel ratio. I'd like to figure out the magic juju that makes some work and some not work.

Could it be dependent on little factors such as what part of the country (air density, pressure, etc) and condition of the whole engine? Perhaps slightly worn parts will not flow as well and such the computer can handle that better?

[Grand1]

So its not cut and dry for a conversion? In the sticky, it seems kind of straight forward.....
so I hear gadget with the air ratio....what are other pitfalls/issues?

[mcninetyone]

I'm also using a Lincoln/HO speed density computer with those GT40's and Explorer cam.

[gadget73]

thats basically it. It'll either run fine, or it will run lean. It may run lean but not so lean as to where its a problem, or it might idle retardedly and pop and do really obnoxious things. It probably has to do with the intake and exhaust. Restrictive parts will hold airflow figures closer to stock values and minimize both performance potential and potential running issues. Or you just tune it and/or do a mass air swap to deal with the better engine parts and carry on.

[pantera77]

So its not cut and dry for a conversion? In the sticky, it seems kind of straight forward.....

A bone stock HO swap will run like a bone stock HO. It's when you start changing things past that that you may or may not run into issues.

[turbo2256b]

Thumper E7s are a waist of money. Better off with a set of GT40s stock. Realy well ported E7s need about a 30% increase in fuel if correct intake and exhaust is used so 25lb are needed, unless you choke the intake and exh air flow. Thumper heads only flow about 30 more CFM than stock. The E7s I have done and sold flow 160CFM total over stock. I ran a 92 Cobra ECM with mine and worked great. There is a point beyond that were the fuel lines on the boxes wount flow enough fuel to supply the engines needs.