E7TE exhaust seat

[travis]

How much bigger than the stock 1.46” exhaust valve can you go before you have to replace the exhaust seat?

For that matter, how far over can you go on most OEM GM or ford heads before you need to replace exhaust seats?

I’ve got a complete set of good GM 1.84”/1.50” valves out of a 305 head I’m considering using on these E7’s, once I verify they are long enough.

[PRH]

Is there something out of the ordinary with those heads? Are they iron?(not a ford guy)
“Most” iron heads don’t have press in seats........ so unless seats have been installed previously.......there isn’t anything to “replace”.

Later model iron heads usually have some sort of hardening process done to the iron to make the heads suitable for use with unleaded fuel.
That process doesn’t seem to go very deep, and just about any increase in valve size will have you machine most or all the way through it.

Depending on how the heads will be used........ that’s either a problem or not.

[travis]

Is there something out of the ordinary with those heads? Are they iron?(not a ford guy)
“Most” iron heads don’t have press in seats........ so unless seats have been installed previously.......there isn’t anything to “replace”.

Later model iron heads usually have some sort of hardening process done to the iron to make the heads suitable for use with unleaded fuel.
That process doesn’t seem to go very deep, and just about any increase in valve size will have you machine most or all the way through it.

Depending on how the heads will be used........ that’s either a problem or not.

Nothing out of the ordinary that I am aware of. And I believe you are correct that OEM iron heads usually don’t have a pressed in seat...usually just induction hardened and it doesn’t go very deep. I’m not sure for a low buck engine if it would even be worth the expense to add hardened seats for a .040” or .080” bigger exhaust valve (1.46” vs 1.50” or 1.54”) on a head that is realistically too small.

[Joe-71]

I have installed 1.9/1.600" valves in literally dozens of E7TE 5.0 heads. Yes you can go to a 1.940" intake, but it does not help with flow, and is heavier, causes some shrouding. The optimum size I prefer is 1.900/1.560 which gives a nice radius on both and good throat size for velocity. Not much difference between the E7 and GT-40 with porting and larger valves, just a little better exhaust on the Gt-40 to start.

[travis]

I have installed 1.9/1.600" valves in literally dozens of E7TE 5.0 heads. Yes you can go to a 1.940" intake, but it does not help with flow, and is heavier, causes some shrouding. The optimum size I prefer is 1.900/1.560 which gives a nice radius on both and good throat size for velocity. Not much difference between the E7 and GT-40 with porting and larger valves, just a little better exhaust on the Gt-40 to start.

Do you install hardened press in seats on these?

[Carnut1]

I agree with Joe, as far as using chevy length valves I have done that as well on E7's. I use the Crane stud kit which has 3/8" studs and a 5/16" base thread with a 1/2" foot. These screw right in with crane locktight. This makes it easier to adjust the valve train. You will still need to figure your pushrod length. Thanks, Charlie

[Joe-71]

I have installed 1.9/1.600" valves in literally dozens of E7TE 5.0 heads. Yes you can go to a 1.940" intake, but it does not help with flow, and is heavier, causes some shrouding. The optimum size I prefer is 1.900/1.560 which gives a nice radius on both and good throat size for velocity. Not much difference between the E7 and GT-40 with porting and larger valves, just a little better exhaust on the Gt-40 to start.

Do you install hardened press in seats on these?

Not needed. If you only cut the seat the minimum you do not go through the induction hardening. Gives a very good radius to work with if porting.

[Walter R. Malik]

How much bigger than the stock 1.46” exhaust valve can you go before you have to replace the exhaust seat?

For that matter, how far over can you go on most OEM GM or ford heads before you need to replace exhaust seats?

I’ve got a complete set of good GM 1.84”/1.50” valves out of a 305 head I’m considering using on these E7’s, once I verify they are long enough.

The 1.540" diameter GT-40 valves of the same length and tip work well, And, the seating area will not go past the induction hardening.

The valves you wish to use also work well if the length and tip are not gonna be an issue;
they are slightly shorter over all length with a shorter tip.
I often use .100" longer versions of those Chevy valves in those heads.

[travis]

How much bigger than the stock 1.46” exhaust valve can you go before you have to replace the exhaust seat?

For that matter, how far over can you go on most OEM GM or ford heads before you need to replace exhaust seats?

I’ve got a complete set of good GM 1.84”/1.50” valves out of a 305 head I’m considering using on these E7’s, once I verify they are long enough.

The 1.540" diameter GT-40 valves of the same length and tip work well, And, the seating area will not go past the induction hardening.

The valves you wish to use also work well if the length and tip are not gonna be an issue;
they are slightly shorter over all length with a shorter tip.
I often use .100" longer versions of those Chevy valves in those heads.

Thanks Walter. Besides trying to make these flow a lot better, the valve tip lengths is something I wanted to address. It’s a bit of a PITA trying to work with very different intake and exhaust installed heights

[travis]

I have installed 1.9/1.600" valves in literally dozens of E7TE 5.0 heads. Yes you can go to a 1.940" intake, but it does not help with flow, and is heavier, causes some shrouding. The optimum size I prefer is 1.900/1.560 which gives a nice radius on both and good throat size for velocity. Not much difference between the E7 and GT-40 with porting and larger valves, just a little better exhaust on the Gt-40 to start.

Do you install hardened press in seats on these?

Not needed. If you only cut the seat the minimum you do not go through the induction hardening. Gives a very good radius to work with if porting.

Thanks!

[travis]

I agree with Joe, as far as using chevy length valves I have done that as well on E7's. I use the Crane stud kit which has 3/8" studs and a 5/16" base thread with a 1/2" foot. These screw right in with crane locktight. This makes it easier to adjust the valve train. You will still need to figure your pushrod length. Thanks, Charlie

I’m going to try those conversion studs. These heads aren’t getting a real aggressive cam...probably an under .500” hft so they should work. Plus I have a set of 3/8” stud 1.6 roller rockers sitting here gathering dust that I want to use.

[Carnut1]

They look weak but held up to 7000 rpm and .544" lift. That was a 1.94"/1.6" combo with heavy Crower stainless roller rockers, steel retainers. We did have the engine chipped for 7000 rpm so it never floated the valves. Thanks, Charlie