Thoughts on this 318 build

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YWGScamp72

YWGScamp72

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Hello looking for input on my 318 build
1972 Plymouth scamp hardtop
Currently stock bore 2bbl 1972 318
Rebuild 30kms ago
Compression 160 psi across all cylinders
904 trans
2200 stall
fully built
Stage 2 shift kit
Posi 8 1/4
3.55 gears
2.5 dual exhaust with thrush v force mufflers
Power steering
Man brakes
No a/c

On order are
Speedmaster 65cc 170cc hyd flat tappet heads with stud kit (black Friday sale 40% off!!!!)
Comp xe268h 10 cam and lifter kit
Double roller timing chain
Mr gasket thin head gasket (.023mil compressed I think)
full gasket set
Billet distributor and 8mil wires
New cha.pion plugs that for new heads
Edelbrock 600cfm 1406
Edelbrock performer intake
Hooker long tube headers
arp torque lube and permatex assembly lube

Planning to reuse stock Rockers, shafts, and pushrods if they are the right length
Let me know if I missed anything or you opinions/ criticism on this build.

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Not a fan of vac secondary carbs its on the smaller size as well
Tunded dp will make more power across the board
 
Awesome thanks for the info. I got the carb and intake with a different motor I bought. I have access to some rebuilt carter 670 and 800 cfm carbs. As for intake I was hoping to work with what I got and port matching. But if it's truly not good enough an rpm or rpm air gap is best I take it?
 
I would use a different intake and carb with those heads and cam. And, you'll need a better converter
 
ch1ll said:
Do not go with a double pumper carb, you will wash oil off the cylinder walls and have gas in your oil.
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Sorry ch1ll. Worst advice I have seen in years. A properly tuned carb is what you need and that my dear sir is your job no matter the size of the carb. Though I myself wouldn’t use an 800 cfm carb on a 318 as mildly built as yours, it’s still something that would have to be tuned.

I’ve used double lumps since I’m 20, I’m 56 now. They can be a lot of tuning points on them to adjust to make them sweeter than sweet. It can be a process if you’re touching everything on them but seldom have I needed to get crazy with them. Here’s why I’d shy away from a DP on this build.

I happen to absolutely love an AVS & a TQ.
Ch1ll made his recommendation on ether of these two old complete gems of carbs and I’ll say if you can find a 750 AVS or a good working TQ, they get the old school nod and vote here as well.

They are (for me) easier to tune and more forgiving and will respond really well. Jet it, set it, forget it. You’re done and they only need minor maintenance. Just keep the air bleeds clear with a shot of brake cleaner once a year. Done!

If an old AVS or TQ isn’t viable or available, the Edelbrock AVS II should be employed.

The Performer is OK for this build but a RPM would be better. Though I would not bother getting the RPM of you already have the performer. If you can do some port matching on the performer as far up the runner as you can, you’ll do just fine.

At such a low power build, you’ll be hard pressed to know the difference unless you go to the track for a time slip. If this is a driver, run what ya got.

If you already have the mufflers, OK and fine. If not, get the Hooker Aero Chambers. (A much better chambered muffler.) You can couple them with a Summit Racing exhaust kit.

IMO, your converters stall is a bit low. It’ll run and drive OK with that 2200 but I’d go 2500 without batting an eye. Go with a good converter company. I know it’s pricey but it is OOOOOO SO WORTH IT!

Look at places like Dynamic, Pro Torque, etc….
Buy once, cry once. At least you won’t have to buy again and cry twice.
 
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YWGScamp72 said:
Awesome thanks for the info. I got the carb and intake with a different motor I bought. I have access to some rebuilt carter 670 and 800 cfm carbs. As for intake I was hoping to work with what I got and port matching. But if it's truly not good enough an rpm or rpm air gap is best I take it?
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You can’t go wrong with a rpm intake for a street car. An avs or thermoquad have air doors on the secondaries, it will use just the cfm it needs.
 
I have run a 2800TC stall on a stock smog-era 318 with nothing but a big TQ and headers, The trans was a A998 with the 2.74/1.54/1.00 ratios. In the rear, mostly I ran 3.55s, but on any given weekend anything could be in there from 2.76s to 4.30s. Car was a blast.
Believe it or not, with the factory cam, I kindof really liked the 2.76s. With a manual shift VB, I would get up into Third ASAP, and enjoy the Thermoquad moan at or near 2800 that seemed to go on forever ........
 
The Performer intake [ not the RPM ] is better suited to the rpm range of the engine size & cam specs.
 
Looks pretty good except the stall is too low and the intake would be better if it were a pref RPM. The carb is personal preference. I've run plenty of carters and Edelbrock carbs and have always been disappointed in comparison to Holley based carbs.
 
Ok well I'm thinking I'll sell the eddy intake and carb. I've found a TQ 800 carb (needs rebuild) and I've been looking at the jegs brand knockoff of the air gap. I've heard some people don't like the air gap (too little heat transfer when cold) but this is a cruiser so hopefully it will compliment the cam and heads without any work.

At the least I'd like to port the intake I have and run a TQ.

As for the converter I'll see what I can find closer to a 2800 stall.
 
If it’s in the budget, i’d go roller cam conversion. Friend of mine just had one lobe go flat on him after a month installed and running. He did a proper break in and was running vr1 oil and he still lost a cam after just one month. I run that xe268h in my 350 s10 with a 2500 stall and 3.25 gears. I would highly recommend a 2800-3000 stall.
 
Are you going to have this thing broken in and run on a dyno?

If so, wait to buy your convertor
 
roccodart440 said:
Are you going to have this thing broken in and run on a dyno?

If so, wait to buy your convertor
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I don't think I have dyno money haha but I'm gonna hold off on the converter until I see how it drives with the new setup. I've also found a Holley 750 dp I'm gonna go with. A local guy is willing to swap the Holley for some parts I have laying around.
 
They can get you close without a dyno sheet, but having one definitely helps.

I always say the 500$ for a break in and tune on the dyno is worth it's weight in gold and is god insurance.
 
Good idea holding off on the c'ter. Another good diea: dump the Holley & use an Edel or TQ carb.
 
So from what I've been hearing not many people like the air gap style intakes as the cam cause poor fuel atomization? As I said I have a performer intake I can use. Would it really be worth it to get a performer rpm? I'm leaning more towards running the 750 Holley on-top of the performer with some port matching. Street car no winter driving. Going to be driven as much as I have time to.
 
YWGScamp72 said:
So from what I've been hearing not many people like the air gap style intakes as the cam cause poor fuel atomization?
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That’s not accurate but it also depends on the build.

YWGScamp72 said:
As I said I have a performer intake I can use.
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Why you haven’t decided to use it yet is beyond me and probably most here.

YWGScamp72 said:
Would it really be worth it to get a performer rpm?
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IMO, No. because the bottom line is it is money spent on something that’s not needed and a most minor amount better at best.

YWGScamp72 said:
I'm leaning more towards running the 750 Holley on-top of the performer with some port matching. Street car no winter driving. Going to be driven as much as I have time to.
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Sounds good to me. But port matching at this level is not going to deliver a great gain. Keep on top of the carb tune until you find the best running and WOT conditions. Pay attention to your plugs as they will tell you all you need to know about the engines running condition.

I don’t know why you’re posting what appears to be a post still questioning what you’re going to do. Just do it. All whom posted generally agree and see it the same way. Carb choice is like underwear choice. As long as it’s well tuned, it’ll be fine.

Just build the dang thing and get on with it already!
 
Thanks for the replies everyone! I just like to test the waters on what y'all think. I'm waiting 9n cam and some other parts still. Speedmaster heads are on the way! Got my shipping notice already. Let's see what the performer and thatb750dp can do with this set up. I appreciate the input from everybody. I'll start a build thread when I start wrenching on the motor. But for now it's kbs rust seal, manual steering conversion, and front windshield replacement time.
 
I think you're gonna be sorry running a DP on a car that isn't pretty much a trailered race car.
 
volaredon said:
I think you're gonna be sorry running a DP on a car that isn't pretty much a trailered race car.
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I currently have three street cars running with DPs. After getting my first DP over 20 years ago, I NEVER went back to a VS.
 
I have much better luck with mechanical secondary on a street engine.
 
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