2 heads better than 1 - power porting E7TE iron.

[novadude]

What a nice little street engine. I'll bet that thing can pull down some serious mpg with an OD and 3.23-3.73 gears.

[Carnut1]

No comments from the dyno crew about the second set of ported heads making slightly less power despite using over 20#/hr more fuel?

No mention of it but it is a good point. So the carb tune wan't changed but the spark was backed down 4 degrees. The rockers are a different brand, one head has studs the other pedestals, both heads ported differently. What of these changes would have made such a difference? The air fuel ratio is nearly identical. Thanks, Charlie

[Carnut1]

No comments from the dyno crew about the second set of ported heads making slightly less power despite using over 20#/hr more fuel?

No mention of it but it is a good point. So the carb tune wan't changed but the spark was backed down 4 degrees. The rockers are a different brand, one head has studs the other pedestals, both heads ported differently. What of these changes would have made such a difference? The air fuel ratio is nearly identical. Thanks, Charlie

Could my textured finish be helping? I would like that.

[Carnut1]

What a nice little street engine. I'll bet that thing can pull down some serious mpg with an OD and 3.23-3.73 gears.

Thanks, one of my all time favorite builds was a snotty 306, milled heads, decked block, lightened forged pistons, ground and polished rods with arp bolts. Similar E7TE heads that flow about 220cfm 1.94"-1.6" performer rpm 600 cfm annular discharge Holley. 228 228 .544 .544 112lc hydraulic roller cam, Crower stainless full roller rockers. Ceramic coated pistons, valves and chambers. 11.0 at 126 mph 22+ mpg high way tko600 tranny and 3.73 gears. Ah the early 90's, good times.

[GARY C]

No comments from the dyno crew about the second set of ported heads making slightly less power despite using over 20#/hr more fuel?

No mention of it but it is a good point. So the carb tune wan't changed but the spark was backed down 4 degrees. The rockers are a different brand, one head has studs the other pedestals, both heads ported differently. What of these changes would have made such a difference? The air fuel ratio is nearly identical. Thanks, Charlie

I would think chamber and or ex port.

Can you show DV's chamber vs the other or is he keeping that under wraps?

EDIT!... I think I found the modified one on page 8?

[Stan Weiss]

Charlie,
Do you know if the air / fuel ratio is measured or calculated? I would guess measured.

Thanks,
Stan

[PRH]

The air fuel ratio is nearly identical.

Okay........ so, 20#/hr more fuel, along with enough extra air to maintain the same A/F ratio....... with the result being a slight reduction in power.

I would think trying to figure out the reason it’s working out like that might be worth looking in to.

Obviously the bsfc numbers are going to be noticeably better with the combo that makes more power with less fuel.

[KnightEngines]

Nice work Charlie, that's some good power with that little cam!

[jcisworthy]

No comments from the dyno crew about the second set of ported heads making slightly less power despite using over 20#/hr more fuel?

No mention of it but it is a good point. So the carb tune wan't changed but the spark was backed down 4 degrees. The rockers are a different brand, one head has studs the other pedestals, both heads ported differently. What of these changes would have made such a difference? The air fuel ratio is nearly identical. Thanks, Charlie

I would think chamber and or ex port.

Can you show DV's chamber vs the other or is he keeping that under wraps?

EDIT!... I think I found the modified one on page 8?

My chambers had an unshroud chamber cut with a radius cutter and a little blending of that cut. That is basically it on the chambers

Other than the valve job,both intake and exhaust runners were gasket matched to stock Ford gaskets then ported.

[jcisworthy]

Basically, what I did would be representative of a "street ported" head that someone could have done with a grinder after having had someone else to the valve job for them.

My understanding was the application is someone with an engine making a decision on using factory ported iron heads or aftermarket heads. What could they expect with the above heads compared to ported aftermarket heads.

[Carnut1]

Charlie,
Do you know if the air / fuel ratio is measured or calculated? I would guess measured.

Thanks,
Stan

I know they have an O2 sensor and gauge added on the wall that I can see during a run. I don't know how the older superflo does it. I will try and find out but today will be a marathon. We would like to test the rest of the heads. Thanks, Charlie

[Carnut1]

No comments from the dyno crew about the second set of ported heads making slightly less power despite using over 20#/hr more fuel?

No mention of it but it is a good point. So the carb tune wan't changed but the spark was backed down 4 degrees. The rockers are a different brand, one head has studs the other pedestals, both heads ported differently. What of these changes would have made such a difference? The air fuel ratio is nearly identical. Thanks, Charlie

I would think chamber and or ex port.

Can you show DV's chamber vs the other or is he keeping that under wraps?

EDIT!... I think I found the modified one on page 8?

Yes, it looks a bit different after milling. Thanks, Charlie

[Carnut1]

Nice work Charlie, that's some good power with that little cam!

Thanks Tony, that means alot coming from you!

[RevTheory]

Don't forget the rum!

[Carnut1]

The air fuel ratio is nearly identical.

Okay........ so, 20#/hr more fuel, along with enough extra air to maintain the same A/F ratio....... with the result being a slight reduction in power.

I would think trying to figure out the reason it’s working out like that might be worth looking in to.

Obviously the bsfc numbers are going to be noticeably better with the combo that makes more power with less fuel.

OK, the fuel specific gravity was change after my E7TE heads were run so John's fuel numbers are more accurate. Thanks, Charlie