A little more oomph

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jrc4y4

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Looking like I gotta pull my heads for valve seals this winter so I’m considering putting a little more into it while it’s apart but still staying in budget. Currently it has Basically stock 72 318 heads. Engine is bored .030 with KB pistons, .470 lift Comp cam, edelbrock performer intake and 600 eddy carb. Stock 72 manifolds.

Looking at doing 302 heads (may put 1.88s in it and porting them), Holley 650, maybe some higher flow manifolds (maybe porting them, but that doesn’t seem to be a common thing?), and porting my performer intake.
It’s got an 8.25 with 3.91 sure grip and a 904 with 2800 stall. Just making sure I’m heading the right direction and not doing anything stupid. Hasn’t seen the track in over a decade, gets into a stoplight battle from time to time, and I like reliability as I regularly drive it around town. Open to suggestions but from what I’m reading I think these are good small updates from current setup.

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Headers or magnum right side and 340 exhaust manifold. Is that the solid or hydraulic .470 lift comp grind? I personally don’t look at the 302 heads as an much of an upgrade, as noted by @MOPAROFFICIAL. I would wait for the speedmaster Black Friday sale and see if they have one this year. But if hanging with iron, your combination looks like it could make use of some 360 heads milled enough to at least maintain what compression you have with the right gaskets. What kind of ignition do you have on it?
 
Hydraulic cam. Here’s my cam card. I’m not closed minded to a J head or X head, just with milling I’d hate to then deal with gasket issues on my intake. And I’ve seen more positive discussions with 302 heads or even 67-69 273/318 heads. Eh aluminum heads will be more than I’m wanting to spend at this point.

I currently have Mopar electronic ignition with an American chrome box and a hot coil from RevNNator. Ive considered doing hei inside a hollow out orange box to keep it looking relatively factory but getting more out of it.

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Port that exhaust on the 318 heads and put on some headers or better flowing manifolds. Dont bother porting the intake, gasket match if anything.
 
Port that exhaust on the 318 heads and put on some headers or better flowing manifolds. Dont bother porting the intake, gasket match if anything.

Youd just port the heads I got? They have a 3 angle valve job is all that’s been done. Small 1.76/1.40 valves or something I’m pretty sure. Ok, so porting the intake wouldn’t be worth the time? Is that cuz the engine isn’t pushing that much through? Sorry. Just wanting to make sure I’m learning what I can.
 
Headers or magnum right side and 340 exhaust manifold. Is that the solid or hydraulic .470 lift comp grind? I personally don’t look at the 302 heads as an much of an upgrade, as noted by @MOPAROFFICIAL. I would wait for the speedmaster Black Friday sale and see if they have one this year. But if hanging with iron, your combination looks like it could make use of some 360 heads milled enough to at least maintain what compression you have with the right gaskets. What kind of ignition do you have on it?
Based on the above post..
I'd either go like you said SM AL and do some more angles to pick up the lower mid lift numbers or SM Mag and do the 1.94's & chamber deshroud. Al would do 250's cfm and the sm mag about the same.
In that flow range both take about the same work almost. 302 are crap without proper work done to them, more work than results warrant if max power is the goal.
 
My buddy has a 318, similar cam specs,mildly ported stock valve 302 heads with headers and a four speed, 3.73 gears. We just swapped the intake and carb to a performer rpm and a holley 750 vaccum secondary carb and it picked up a little over 3mph. I like the performer for a daily but its a cork at the track.
 
[1] Replacing an AFB style carb [ Edel ] with a Holley would be a backwards move....
[2] Cam is a good compromise for drivability, power, longevity.
[3] I would mill the heads for 9.5:1 CR, even if it means milling the intake faces for intake alignment. Compression makes more power EVERYWHERE, whereas other mods may only make more power in some part of the rpm range.
 
I feel like I post this once a week...so here goes the 1st for this week. From a performance stand point, I would avoid the 302 heads. It would be a waste of money. Years ago I had a 318 in my Barracuda with home ported J heads. I swapped heads for a set of 302's that I also home ported and the car slowed down over half a second (slowed from 13.9 in the 1/4 to 14.5 with very similar density altitude). Neither head is performance oriented, but at least the J's can make a little steam.
 
Seems like most of the low hanging fruit you have already picked. You might look into setting up a cold air, air cleaner setup with the ducts. The only thing to really do to the exhaust manifolds is port match them and ceramic coat them inside and out. They are the highest source of heat in the engine compartment. 500+ degrees.
 
It may not be budget friendly, but after seeing MOPAROFFICIAL’s response with the speedmaster/ProMaxx magnum heads and having first hand experience with magnum power, that’s my favorite option here. Maybe see if they’re available for sale on Black Friday. Get their air gap intake while your at it. Upgrade springs and retainers for extra lift, and I would probably upgrade to this cam being you’ve already got 3.91 gears and 2800 stall. The 1.6 rocker ratio makes .507/.532 lift.
Howards Cams, Retro-Fit Hydraulic Roller Camshaft & Lifter Set, Chrysler SB, 221/225 @ .050, .475/.500, 112 LS-Competition Products
 
[1] Replacing an AFB style carb [ Edel ] with a Holley would be a backwards move....
[2] Cam is a good compromise for drivability, power, longevity.
[3] I would mill the heads for 9.5:1 CR, even if it means milling the intake faces for intake alignment. Compression makes more power EVERYWHERE, whereas other mods may only make more power in some part of the rpm range.

Is there a reason against the Holley? I’ve seldom heard someone favor a Carter over a Holley other than drivability.
 
Is there a reason against the Holley? I’ve seldom heard someone favor a Carter over a Holley other than drivability.
For a street car I would go with the carter all day long. In my experience, holleys dont hold their tune. A carter you can dial it in and your done.
 
For a street car I would go with the carter all day long. In my experience, holleys dont hold their tune. A carter you can dial it in and your done.

Makes sense. I usually get away with tuning the carb once a year. Would you run anything bigger than 600?
 
As Furry mentioned above , carb sealed to outside air is good bang-for-the-buck .
 
The performer intake is NOT for "performance", in my experience just an intake swap to an rpm or similar would definitely help, and headers.
 
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