Big horsepower 318 builds

-
It's not that I especially care about about gm products. I've never owned one. I'm just a little hung up on why a 5.2 sbm couldn't make similar power to a 5.3ls, with similar specs.

Seems the more sophisticated heads and intake are the biggest thing.

View attachment 1716281342
Could SM/Edelbrock/TF heads be ported to a level to close the gap highlighted above? The LS head is doing at .500, what it takes the sbm head .700 to achieve.

I can't imagine that it would be THAT hard to do.. someone has to have ported a set, I know TF CNC ports them but they also leave large margins for safety (from breaking through, core shift and to avoid warranty issues).. 16cfm @.500 has to be possible...
 
You guys think the Chevy guys are having an intelligent discussion about Mopar heads this morning? :poke: :rofl: :rofl: :rofl: Na, probably not.
 
You guys think the Chevy guys are having an intelligent discussion about Mopar heads this morning? :poke: :rofl: :rofl: :rofl: Na, probably not.
Cause most of their unported LS stuff beats the snot out of most any production Mopar head with port work.
 
It's an efficient design. Someone did some homework
Indeed they did. As far as I'm concerned, Chevy's been well ahead of Mopar since they started production of the one piece rear main seal blocks way back in the 80s. I'm still stunned Mopar didn't pick up on that, when both Ford and Chevy did it about the same time.
 
I can't imagine that it would be THAT hard to do.. someone has to have ported a set, I know TF CNC ports them but they also leave large margins for safety (from breaking through, core shift and to avoid warranty issues).. 16cfm @.500 has to be possible...
I'm not a head porter so I don't know. I do know from having seen guys here porting and testing what changes yield increases in flow, a 20cfm jump seems like a pretty big deal, especially if you're already starting out with a refined head like the TF
 
I'm not a head porter so I don't know. I do know from having seen guys here porting and testing what changes yield increases in flow, a 20cfm jump seems like a pretty big deal, especially if you're already starting out with a refined head like the TF
Did a quick search and found a set PBR did that pretty much match those heads... but it looked like a lot of work...
 
Here's a 5.7L hemi makes 500 + hp NA with ported heads and 224 cam and single plane intake which is known not to be the greatest, would it still make 500 hp with a 3.31" stroke who knows but I'd say it's possible.

 
Last edited:
I'm not a head porter so I don't know. I do know from having seen guys here porting and testing what changes yield increases in flow, a 20cfm jump seems like a pretty big deal, especially if you're already starting out with a refined head like the TF
From what I've notice that most street strip type builds fall in the 1.7-1.9 hp per cfm range, some get 2+ hp:cfm, so I use 1.8 as average reasonable power potential.
 
The problem is finding R/T heads. You’d be lucky to find them to start with. I was with the above heads and traded a set of Edelbrock heads for them. This was the direction of the other guy and I have a curiosity about ‘em. The above are the 2.02/1.60 heads. They flowed pretty good for a OOTB casting.

There was a guy at my local swap meet that had a pair of R/T heads, new and still in the box. Pretty sure they were of the 1.92 variety like I run. He wanted $1000, no idea if he sold them.
 
There was a guy at my local swap meet that had a pair of R/T heads, new and still in the box. Pretty sure they were of the 1.92 variety like I run. He wanted $1000, no idea if he sold them.
That’s pretty good. A bare edelbrock is $743 @ Summit racing.
Considering the R/T can be ported past 300cfm, the only draw back is the weight. The pro is longevity of an iron head.
 
One of my sons, about 4 years ago, got a full 360 magnum for $150 with R/T heads. It was advertised as such on FB Marketplace. Being sure it was a mistake, I messaged the guy and asked if the heads had a big R/T cast on them. He sent pics, and my son and I were burning rubber to go get it. He bought the 360, and I picked up quite a few parts for yardsale prices.

The young guy was into Fords, and had bought a house with the Mopar stuff in the garage.

Sometimes you get a deal!
 
hey guys, figured i would ask here rather than make a new post... My engine has magnum roller lifters, hardlan sharp (mancini) rockers.. i have been hearing a bit of lifter noise, not bad but i shouldn't hear any. Was curious if anyone knows how many thousandths 1 turn of a HS adjuster is for preload? I did a search but didn't find it..

Also, i believe preload should be .035? Can anyone confirm? If i had a couple with too much preload would they not pump up properly? the noise isn't even as loud as a solid cam, just annoys me i can hear it at all
 
hey guys, figured i would ask here rather than make a new post... My engine has magnum roller lifters, hardlan sharp (mancini) rockers.. i have been hearing a bit of lifter noise, not bad but i shouldn't hear any. Was curious if anyone knows how many thousandths 1 turn of a HS adjuster is for preload? I did a search but didn't find it..

Also, i believe preload should be .035? Can anyone confirm? If i had a couple with too much preload would they not pump up properly? the noise isn't even as loud as a solid cam, just annoys me i can hear it at all
Lifter preload must be more than .010 and I would not exceed .060 though there is more on that lifter.

It’s also not unusual to here a Magnum roller lifter lightly tick.
Swapping lifters until there is t a tick is a big PIA - IMO but rather cheap to do since it’s an inexpensive lifter vs a solid roller lifter.
 
Lifter preload must be more than .010 and I would not exceed .060 though there is more on that lifter.

It’s also not unusual to here a Magnum roller lifter lightly tick.
Swapping lifters until there is t a tick is a big PIA - IMO but rather cheap to do since it’s an inexpensive lifter vs a solid roller lifter.
ahh ok, yeah it's a very faint noise.. if it's normal i won't sweat it and yeah i paid $100 for a set of them, i can live with a little noise :)
 
ahh ok, yeah it's a very faint noise.. if it's normal i won't sweat it and yeah i paid $100 for a set of them, i can live with a little noise :)

I have always wondered, if some of the faint noise in these magnums could come from the dogbone and spider.
 
I have always wondered, if some of the faint noise in these magnums could come from the dogbone and spider.
Dunno... the noise is so like muted that i'm not sure what would make it.. it's really muted.. i think if the dogbones were making it that would be bad..
 
ahh ok, yeah it's a very faint noise.. if it's normal i won't sweat it and yeah i paid $100 for a set of them, i can live with a little noise :)

The 5.9 I am using came out of my daughters Durango w/80,000. You can’t hear **** inside a Durango. I never heard a blessed thing with the hood up while it was running n the Durango but it also had that massive and noisy fan. Now that it’s in my ‘79 Magnum, I hear a super faint lifter tick and each pulse on the header on the tubes.

The ‘79 and even more so on the earlier year vehicles all have a lack of sound deadening material. The firewall is the most notable place since your now hearing it only through the metal firewall and minor sound deadening material.

The Durango has much more sound deadened and other under hood items in the way.
 
The 5.9 I am using came out of my daughters Durango w/80,000. You can’t hear **** inside a Durango. I never heard a blessed thing with the hood up while it was running n the Durango but it also had that massive and noisy fan. Now that it’s in my ‘79 Magnum, I hear a super faint lifter tick and each pulse on the header on the tubes.

The ‘79 and even more so on the earlier year vehicles all have a lack of sound deadening material. The firewall is the most notable place since your now hearing it only through the metal firewall and minor sound deadening material.

The Durango has much more sound deadened and other under hood items in the way.
yeah, i can't hear it in the car at all, i was working on the engine the other day and noticed it.. it's not loud at all, just surprised it was there
 
Dunno... the noise is so like muted that i'm not sure what would make it.. it's really muted.. i think if the dogbones were making it that would be bad..
You could be right, just something I wondered since they all seem to have a little noise.
 
ok.. just to verify.. did some math.. The adjusters on the hardland sharps are 24 thead/inch which 1/24 is .041 per turn? sound right? i was messing around last night before doing math and i only had bout 3/8 of a turn preload, so i think i found my noise.. gonna relash tonight at 1turn and see how it sounds.
 
ok.. just to verify.. did some math.. The adjusters on the hardland sharps are 24 thead/inch which 1/24 is .041 per turn? sound right? i was messing around last night before doing math and i only had bout 3/8 of a turn preload, so i think i found my noise.. gonna relash tonight at 1turn and see how it sounds.
Is this the Trick Flow 318, we got her up and running ?
 
Is this the Trick Flow 318, we got her up and running ?
it's mine yeah.. been running for like 6 months, just some valve noise so i'm double checking stuff.. and i didn't have enough lash for sure.

I will say.. the blue silicone valve cover gaskets were worth every penny at this point
 
Is this the Trick Flow 318, we got her up and running ?
In case you hadn't heard it :) i fixed the damn header leak 2 days ago also... can't deal with exhaust leaks
 
In case you hadn't heard it :) i fixed the damn header leak 2 days ago also... can't deal with exhaust leaks
THat sounds Hangry! Better feed it a Snickers!
 
-
Back
Top