New heads?

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tony20110

tony20110

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I currently have J heads, polished and ported on my 360la. I’m right at 385hp and looking to squeeze some more power out. If a head upgrade is my answer what would everyone recommend? TIA! Wishing everyone a very merry Christmas.
 
I would consider a 385hp 360 a pretty mild build(btw...... how are you determining you currently have 385hp? Dyno? Track results? Rough guess?)
Assuming the combo is some variation of the typical components that would be used to get you to that point, I wouldn’t expect a set of different heads...... and NO OTHER CHANGES......to make enough of a difference in power to justify the expense.

Imo, a better approach would be to figure out where you want to end up, power wise, and then make up a list of the changes you think would be required to get you to that point.
Then..... start buying some parts.
 
PRH said:
I would consider a 385hp 360 a pretty mild build(btw...... how are you determining you currently have 385hp? Dyno? Track results? Rough guess?)
Assuming the combo is some variation of the typical components that would be used to get you to that point, I wouldn’t expect a set of different heads...... and NO OTHER CHANGES......to make enough of a difference in power to justify the expense.

Imo, a better approach would be to figure out where you want to end up, power wise, and then make up a list of the changes you think would be required to get you to that point.
Then..... start buying some parts.
Click to expand...

Thanks,
PRH said:
I would consider a 385hp 360 a pretty mild build(btw...... how are you determining you currently have 385hp? Dyno? Track results? Rough guess?)
Assuming the combo is some variation of the typical components that would be used to get you to that point, I wouldn’t expect a set of different heads...... and NO OTHER CHANGES......to make enough of a difference in power to justify the expense.

Imo, a better approach would be to figure out where you want to end up, power wise, and then make up a list of the changes you think would be required to get you to that point.
Then..... start buying some parts.
Click to expand...
Thanks, I built the engine based on a build sheet that makes 385-400hp. It’s been a great, reliable build for 4 years. Just looking for options to make it a little more exciting.
 
I'd get aluminum heads, weight,better port design/combustion chamber and potential to make more power in the future.
 
throw a set of low buck '87-'92 '308' heads on it and see what happens. Start porting those or pull trigger on AL ones. IDK what HP per buck your looking at. Ported LA heads may be about what Magnum/AL heads start at or considerable higher. You cant go wrong with the new crop of offshore AL heads with proper prep work before they go on. Why someone doesn't repop the 'econo' W2 head is strange to me. Seems the offset rockers could be repopped just as easily in the age of $99 AL or stainless rockers.
 
How about a few more details about the current combo.

Any track results?

About 30 years ago I helped my father put together a 360 for some bracket race use in his 3960lb 1979 Córdoba.
I gave him some pointers, and he did the bulk of the porting to the J heads himself(no flow numbers...... but probably 240 or less).
Flat top TRW’s, 509 cam, Torker 2....... it didn’t quite crest the 400hp mark(398 iirc).
With slicks, a 9” converter, and 4.56 gears it went mid-12’s.
 
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New aluminum heads won’t result in any magic on an otherwise mundane build.

We had a stock dish piston rebuild type 360 on the dyno here a year ago or so.
XE268 cam, RPM intake, ootb SM heads.
It only made
367tq@4600/331hp@5200.

Those heads flowed 250.
 
This is where my 200 by .300
Rule really comes into effect. Sure 280cfm@.700 is nice but woop te doo if you are only running a .500 lift cam. That’s why even with Speedmaster, Edelbrock heads I strive to reach 200 plus at .300 and rapidly climb after that. With an intake to match.
 
My question would be is the current combo optimized tune, fuel and drive train wise? I've see some combos make less than they should due to poor tuning and incorrect carburation and/or calibration.
 
pittsburghracer said:
This is where my 200 by .300
Rule really comes into effect. Sure 280cfm@.700 is nice but woop te doo if you are only running a .500 lift cam. That’s why even with Speedmaster, Edelbrock heads I strive to reach 200 plus at .300 and rapidly climb after that. With an intake to match.
Click to expand...


I like that rule.
 
PRH said:
New aluminum heads won’t result in any magic on an otherwise mundane build.

We had a stock dish piston rebuild type 360 on the dyno here a year ago or so.
XE268 cam, RPM intake, ootb SM heads.
It only made
367tq@4600/331hp@5200.

Those heads flowed 250.
Click to expand...
I’d think in the OP’s case he’d want to look at any combination of: cam upgrade, porting the heads, porting the intake or upgrading, a converter and possibly gears. There was a time where that’s what you did for more power as there was no such thing as aftermarket heads for the average guy. You had the heads you had and increased power by porting and upgrading the other stuff. I recall it actually working too, likely make more power (be cheaper) with a few peripheral changes than just some aftermarket heads. No?
 
likely make more power (be cheaper) with a few peripheral changes than just some aftermarket heads. No?
Click to expand...
Quite possibly.
In my mind it mostly depends on what you have/where you are to start with.
(To me a “385hp” 360 would be something like 9-9.5:1cr, bowl blended 2.02 heads, good dual plane, 650 carb, headers, 225-230@.050 hyd cam)
Of course, the OP’s motor hasn’t been tested..... so who knows if it’s 385hp...... or 350...... or 425?

In comparison to the SM headed build I mentioned above, I had another 360 on the dyno that was here for a cam swap.
I pulled the heads and gave the valve job a touch up. They had already been bowl blended(I dont know by who)..... flowed 230-ish.
I milled them for a true 9.7cr, and installed a small custom solid cam. The intake was a LD340, and I ran it with an Ede 750 and my Holley 750 dyno carb.
Both carbs made close to 420hp.

So, a better “overall” combo..... but with smaller, lesser flowing heads....... and the result was close to 90hp more.
 
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