E7's have the same valves as the rest of the 302 heads-- 1.78/1.45. They flow a bit more due to port revisions that improved them over the earlier stock small block heads. Simply doing a couple hours work on the exhaust side improves them even more. GT40P heads flow better than the E7's, but they have a relocated spark plug, that centered the tip in the chamber and to do this, the angle of the plug was changed. This change results in interference in many small block header tubes. The bolt pattern is the same as others, but the plug angle causes problems.bad68coupe said:How large are the e7 valves?
and what about GT40 heads?
i was also interested in the GT40P heads but i heard they require some sort of special header is that correct?
68stangman said:The only heads I remember reading about that would give a benefit is a '69 or '70 351 head. The valves are somewhat larger. Intake is 1.84 versus 1.78, and exhaust is 1.54 over 1.46
They were great back then because they looked just like a 302 head, and your oponent could not tell your engine was better breathing. There were very limited aftermarket options back then. That head swap was about as good as you could get for the money.
Today, it would still be an upgrade, however, there is an aftermarket out there with better options. If I had the 351 heads already in hand, I would be inclined to use them. I would definately have them worked on. At least a three angle valve job and hardened seats (unleaded gas). I would also want bronze valve guides.
If I didn't already have them, I would not seek them out.
I'd just rather go aftermarket or rework E7's and have the 1.9/1.6 valves installed.
My .02
bad68coupe said:What are hardened seats?
Rusty67 said:They are on my friends Cougar I've been working on. I never tried bolting anything else on them but I think you might have problems with headers. The ones we are using are Ford motorsport. We had to dimple the headers to get the damn things to clear the steering box. I'm sure it would be worse with a manual trans, we put an AOD in his car. Passenger side fit just fine.
There are two types of hardened seats. One is the factory inductioned hardened where they heat the seats to a certain temp with a tool much like a soldering iron, then quench them. This results in a hardened layer a few thousandths thick on the surface of the seat. The other type is where the machinist cuts out a large amount of metal from the seat area and presses in a hard steel seat to replace the metal removed. On the exhaust side of the small block ports, there is a protruding casting for the Thermactor Air injection passage. I remove the protrusion, widen the port, raise the roof and blend this all down into the area under the valve. I smooth the area under the intake side as well. I leave the stock valves in the finished head. I have a local machine shop do the valve job afterward and they use a Serdi machine to surface the seats (the end result is something akin top the old 3 or 5 angle valve job)bad68coupe said:What are hardened seats? and what kind of work are you talking about on the exhaust side Hearne? lastly i found a set of E7 on ebay, and they are old, i know i have to have them magnafluxed but what other kinds of machining needs to be done before they are good to go, should i replace the valves?
D.Hearne said:There are two types of hardened seats. One is the factory inductioned hardened where they heat the seats to a certain temp with a tool much like a soldering iron, then quench them. This results in a hardened layer a few thousandths thick on the surface of the seat. The other type is where the machinist cuts out a large amount of metal from the seat area and presses in a hard steel seat to replace the metal removed. On the exhaust side of the small block ports, there is a protruding casting for the Thermactor Air injection passage. I remove the protrusion, widen the port, raise the roof and blend this all down into the area under the valve. I smooth the area under the intake side as well. I leave the stock valves in the finished head. I have a local machine shop do the valve job afterward and they use a Serdi machine to surface the seats (the end result is something akin top the old 3 or 5 angle valve job)
The pressed in seats will give longer service, thru multiple valve jobs due to the thicker hardened steel. After two valve jobs with induction seats, the hard metal will have been removed. Their purpose is to keep the valve from pounding into the head, they weren't needed before the introduction of leaded gas, the lead served as a cushion between the seat and valve.bad68coupe said:is one of those types of hardened seats better than the other? and what purpose do they serve?
D.Hearne said:The pressed in seats will give longer service, thru multiple valve jobs due to the thicker hardened steel. After two valve jobs with induction seats, the hard metal will have been removed. Their purpose is to keep the valve from pounding into the head, they weren't needed before the introduction of leaded gas, the lead served as a cushion between the seat and valve.
bad68coupe said:am i really going to need to do that much work just for my 302 daily driver?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?