Scream'n 318 ?

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@RussellSullivan Do NOT polish the heads intake runners. Chamber? Yes! Good.
If you can port yourself (I’ll assume so) or have it done for you, great. That’ll free up some power!
 
flyfish said:
Oooook, well, it makes a little more sense now. I saw the title of the thread and thought you were actually building something....you know....Fast (scream'n)....like a 10 second 318 that spins up in the stratosphere.
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A reoccurring theme... LOL...
 
rumblefish360 said:
@RussellSullivan Do NOT polish the heads intake runners. Chamber? Yes! Good.
If you can port yourself (I’ll assume so) or have it done for you, great. That’ll free up some power!
Click to expand...
Yes. I wish I was this handy but I traded this job for some tools. (Electric die grinders) LOL Oops, getting side tracked.

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RussellSullivan said:
What's your opinion on those roller cam 318s, with 302 heads, as opposed to the earlier 318s? I've got one I'd like to do the same high revving build you're doing. I think they all need help breathing, to start.
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If you want to go roller cam, then the roller block is the way to go. I'm not a "big" fan of the 302 heads for any kind of performance. 302's seem to work fine in next to stock applications.
 
flyfish said:
Oooook, well, it makes a little more sense now. I saw the title of the thread and thought you were actually building something....you know....Fast (scream'n)....like a 10 second 318 that spins up in the stratosphere. Then I saw that you were looking at stock iron heads and the word "fast" went right out the window, lol. Still, sounds like you will have a spunky little 318 that makes good steam.

Considering your budget, I think you would get a lot more bang for the buck with a solid flat tappet cam (vs an expensive roller) and put your $$$ into something else (better heads maybe). Best of luck with the build.
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Yeah, don't hang out here expecting to find a recipe for pulling your low 10 second stroker to go 8.50's with a cast crank 318 for a few hundred bucks. Trust me, if I do that you'll pay me 10k just for the recipe :D :D
 
rumblefish360 said:
@RussellSullivan Do NOT polish the heads intake runners. Chamber? Yes! Good.
If you can port yourself (I’ll assume so) or have it done for you, great. That’ll free up some power!
Click to expand...


I’ve stopped polishing the chambers. I use a stone with WD-40 if I’m doing aluminum and I’m very close to testing a burr finish in the chambers. Or at least certain parts of the chambers anyway.
 
yellow rose said:
I’ve stopped polishing the chambers. I use a stone with WD-40 if I’m doing aluminum and I’m very close to testing a burr finish in the chambers. Or at least certain parts of the chambers anyway.
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It helps with detonation doesn't it?
 
yellow rose said:
Nope. Learned the hard way it promotes detonation. Counterintuitive I know, but true. The smoothest I would make them now is a 60 grit paper roll and I’m s kiddish about that.
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True, I have most of my stuff smoothed. I did say polished yes, but in retrospect, an actual polishing glass smooth surface would be wrong IMO.

Let me restate that a chamber should have no sharp or rough edges and be smoothed out to reduce the highs and lows of the metal.

YR is correct. Counter intuitive. The old idea was to nullify any spots for detonation purposes and reflect heat back. Heat is power. But not to much heat.
 
yellow rose said:
Nope. Learned the hard way it promotes detonation. Counterintuitive I know, but true. The smoothest I would make them now is a 60 grit paper roll and I’m s kiddish about that.
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I usually leave the chambers "as cast". I just remove casting flaws. If I do anything, maybe smooth around the exhaust valve for a smooth exit. But usually not.
 
318willrun said:
I usually leave the chambers "as cast". I just remove casting flaws. If I do anything, maybe smooth around the exhaust valve for a smooth exit. But usually not.
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You’ll have a better exhaust if you relieve the chamber around the exhaust port some. Clearance around the valve cylinder wall side by at least .060.
 
Boy, ordered my parts this morning and ended up way under budget!!!!! Can't wait to get this screamer together!!!!!!
1st the cam....
Summit Racing SUM-6900 Summit Racing® Classic Camshafts | Summit Racing

Lifters....
Rhoads Lifters 2018 Rhoads Original Hydraulic Flat Tappet Lifters | Summit Racing

carb.... 400 2bbl on the 360 2bbl intake will have more low end crunch than a 408 from off idle, especially with the cam advanced 4* and the Rhoads lifters
Uremco 6-6139 UREMCO Remanufactured Carburetors | Summit Racing

I'll use the 302 heads on DT, and with my port job I'm hoping they flow around 240 @ .450 lift. Even though they are closed chamber, I'll use some of all the left over money to mill an additional .050 and hopefully that puts me at 9.8 to 1 with Fel Pro 1008 gasket.

Oh! I plan to dremel the divider out of the plenum of the 360 intake making it more of a single plane. That intake should flow what the heads will flow then.

:thumbsup: Scream'n 318
 
Rhodes delivers between 10 & 15 degrees of less duration up until approximately 3K. Cam intake duration at 050 is 204. 204 - 15 equals 184@050... 184?!?!?!

Coupled with a 2800-3200 converter?

What is the gear ratio again?
And tire size?
 
318willrun said:
I'm not a "big" fan of the 302 heads for any kind of performance. 302's seem to work fine in next to stock applications.
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Yeah 302's are junk. Car still managed a 12.6 @ 107 with 1 dead cylinder another with heavy scoring and an electric fuel pump that was disconnecting during the run and ran lean at mid to top end of the track. Add to that a lowly performer manifold and a 600 edelbrock with a 222/234 hydraulic cam. Did I mention it only has about a 140 cc intake port volume.......

Again saw a 318 with ported 318 heads stock valves run 12.7's in a stock sedan that had to be at 3400 without driver.

Airflow is is one thing using it is another. When all else fails put bigger heads on it and spin it higher because you cant extract the efficiency at lower rpms to get the car to make the power you need.
 
318willrun said:
If you want to go roller cam, then the roller block is the way to go. I'm not a "big" fan of the 302 heads for any kind of performance. 302's seem to work fine in next to stock applications.
Click to expand...

Just want something to move a little A body around town
rumblefish360 said:
True, I have most of my stuff smoothed. I did say polished yes, but in retrospect, an actual polishing glass smooth surface would be wrong IMO.

Let me restate that a chamber should have no sharp or rough edges and be smoothed out to reduce the highs and lows of the metal.

YR is correct. Counter intuitive. The old idea was to nullify any spots for detonation purposes and reflect heat back. Heat is power. But not to much heat.
Click to expand...

Exhaust runners would be the only thing to really polish. Really I'd just be opening up the ports and knocking down burrs everywhere else
 
RussellSullivan said:
Any idea how they respond to mild home porting and larger valves?
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I had them on a low comp 360 with a 1.84 valve with very little if any porting. All I can say is that the acceleration was nothing short of astounding, brutal but beautiful all at the same time. It was still pulling at 6000 RPM where the limiter was set on the 6AL

It had a 256 @ 0.050 solid but still made 185 psi on the comp test.
 
Hysteric said:
I had them on a low comp 360 with a 1.84 valve with very little if any porting. All I can say is that the acceleration was nothing short of astounding, brutal but beautiful all at the same time.

It had a 256 @ 0.050 solid but still made 185 psi on the comp test.
Click to expand...

The real reason they're attractive to me is that I already have them, and it will be a budget build. That, coupled with the closed chamber. Valves are tiny, but that can and will be addressed.

Seems most people go the other way - 318s with 360 heads. Interesting that you did the opposite.
 
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