Strip to Street Help Needed

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trevorcrum

trevorcrum

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Hello All,

New member, new to the hobby, first post so go easy but I do need some advice.

I bought a 74 Duster 360 CI bored .040 over W/ TRW forged pistons. Factory rods and crank, " J " heads fully ported W/oversize intake valves, Direct Connection headers, Mopar M1 intake manifold, Holley 600 double pumper, Lunati Voodoo 60404 camshft, TCI-142200 10" Converter, 727 Transmission W/shift kit, 8 3/4 rear end W/ 3.90 gears and a posi carrier.

The price was right, but I'd actually like to tame it down a little and use it more as a driver than the previous owner was going for.

Currently, the car when cold needs to warm up before it can idle, so I spend 5 mins revving the engine up to 2-3K or driving it around the block riding the brake a little. When it does finally idle, it's around 600rpm and lope-y as hell. I'm assuming that I need a milder cam to help out with the idle, but will I have to swap out anything else ? Lifters, push rods ? Any cam suggestions ?

Again, take it easy please.....

Trevor.
 
and the 64k question is.....where is the timing set at? .....the Initial timing that is...........
 
Repeat^^

And why is the idle speed set so low?That engine should idle at 750ish/Neutral.
This cam has specs of 276/284/110LSA,adv;..234/242@050... 513/533lift. As cams go this is mild. Would make a nice pkg, with the right C/R. I know this because I have a very similar cam. Mine is waaay too smooth sounding for me. Get the tune right before you yank it out. Mine warms up in 1 to 2 minutes,tops, with no choke.And runs on its own within 1 minute.
............................................Tune-it
Most guys will tell you that, that engine wants 18* of idle timing, and up to 36* of power timing. They will tell you that the timing should be all in by 2500.The vacuum advance is a separate deal and a separate tune.
Mine has aluminum heads. My idle timing is about 14*, and power timing is about 32*. My curve starts right around 850 flies to 28*/2800, and then slows down to add 4 more by around 3400 or so.This requires 2 separate kinds of springs, but allows me to run 87E10 with 10.7 compression ratio.My vacuum advance can flushes out the curve under part throttle conditions to help drive-ability.
Actually its more than a help. That can saves me a bunch of money at the pump, too.
.............................................Tune it
 
If you change cam you will need new lifters, never run a new cam with used lifters.
 
Purple Haze said:
If you change cam you will need new lifters, never run a new cam with used lifters.
Click to expand...

X2 but I think you can make that cam work just fine. You can easily adjust the idle with the adjuster on the carburetor and timing. There's a lot hotter combos out there cruising the streets.
 
What are you going to do about smog cert, or is that an issue?
 
Thanks for the help guys, you are making me feel easier about the current setup. I'll start tuning tomorrow and see where it takes me. Smog cert ? Damn, I guess I have to look into that.
 
Yes, do you have to pass any emissions tests?
 
Tell ya, Rumble, if I was unlucky enough to be "stuck" in any o' them smogocrat places, I'd have a bone stock 318 under the bench, and just plan on slippin' it in there every couple years for a week or too, LMAO
 
In Az, there is no need to pass emission test if you insure the car as a classic. Otherwise, yes you have to pass emissions.
Or at least that's what the DMV told me today, so I'm going this route.
 
No Emissions if you Get classic. But when I got it for my Valiant the lady at the DMV didnt accept it cause their policy only alows no emissions on Collectors cars. So I called my insurance guy and had him delete the classic and put collectors. Went back and the accepted it fine and now no more emissions. I pay 32 bucks a month for my truck and car on "collectors" insurance. When I get my plymouth done I will put better insurance on it. The other emissions exempt is if you live out of city limits there is no emissions are required.
 
One more thing is that if the EPA ever signs off on the new law that was passed back in Apr 2011 you won't need to emission for anything 74 or older.
 
Turn the idle up to 800 and check timing.

also, does it have a t-stat?
 
Yeah Ive been hoping they pass that law. But until than we have to find ways around it. I got rid of all the smog stuff from my 79 powerwagon when I got collectors insurance. Plus its nice to do what ever I want to my Valiant and not have to worry about emissions. I have SafeCo insurance out of Casa Grande. They just require a few pictures and say i can only drive it 1000 miles per year. But they have never checked me. I did it all over the phone and e-mails
 
a little further than out of the city limits. Those apply to the county you live in. Only 2 counties in all of AZ require emissions testing.
 
That intake is a single plane designed more for upper mid-range & top end. An Airgap would give you more torque down lower. first things first though. Dial in your initial & total timing as previously mentioned, along with your advance curve and vacuum advance. Be sure it's hooked to manifold vacuum, so it will retard as you open the throttle and load the engine. Also, be certain you don't have any vacuum leaks and have a thermostat.

You will likely benefit greatly from using a wideband A/F meter to adjust mixtures on your carb.
 
But there is no emission requirements in Avra Valley and Sahuarita. my neighbor had some land in Avra Valley and he Didnt have to go through emissions. Also I had an ex that lived in Sahuarita and I used her address to escape the emissions for 2 years.
 
if you dont have a light and at the moment you could always just turn up the initial until it runs smooth at idle. back down the idle to 850 limp around till it gets warm. shut it off in your driveway and see if it starts again. if it kicks back, back it off until it starts. limit the mechanical to around 34 and let her eat.
 
So far as licensing it as "collector" or whatever, doesn't this legally limit you on mileage? I would not want that. These states like AZ with archaeic emissions laws need to get off the stick. ****, how many of these cars ARE there? How many do you SEE every day? It's not like hundreds or thousands are being used for DD and making "LA like the old days"
 
67Dart273 said:
So far as licensing it as "collector" or whatever, doesn't this legally limit you on mileage? I would not want that. These states like AZ with archaeic emissions laws need to get off the stick. ****, how many of these cars ARE there? How many do you SEE every day? It's not like hundreds or thousands are being used for DD and making "LA like the old days"
Click to expand...

Thats why i went with my isurance company. They havent even checked how many miles ive driven in the last 3 years. There are so many classic cars just in Tucson. Its BS that they make it so hard for us.
 
If you really,really want to make it into a driver, and are concerned with the cost of fuel,NVH, an engine wear, then put a custom cam in it.
You will want to stick around 218 to 225 intake duration, go to 112 to 114 LDA. And get the fastest possible rate of lift,and as much lift as the heads will allow.This will net you a very broad torque curve that starts right off idle. You will need some special springs for that, and the cam grinder might give you a lower than expected red-line, to keep it all together.I have tuned a 223* cam to get 32 MpgUS, so I know its in there.With this small cam,compression will be up.It will have gang-buster-grunt off the line, and with its fast rate it will appear 1 or 2 sizes bigger than it is, through the midrange. But the top end will be down.This combo will shine with a spread-bore carb.
I built a combo like this for my S. It was awesome.It would smoke the 275/50s through second gear (1.92 x 3.55= 6.82ratio) to near red-line (street suspension,remember).It would break em loose in 2nd, as early as 2500rpm, and as late as 45mph.The tranny had a GV behind it (still does). Swapping out the 750DP for a 600VS,and installing a Mopar o/d box(giving me a double o/d) it made the 32mpg number, on a trip to CarCraft (Minneapolis)in 2004, with the tranny combo turning the 3.55s into1.97s. 85mph was 2180rpm. 65 was1667! Starter gear was 10.97.
Iknow, I know. Thats cheating. I'm just giving you ideas and results.
The thing is, with a custom cam like above, you wont need to run performance gears. You wont even want to. If you get the tune right, it will be awesome with 3.23s or even less, if you get a low gear 904 with a lock-upTC.
That combo(A-998lowgear-loc-up, the 223/114LDA cam,and with a Dcr of 8.5 or so for Iron heads ) will pull 2.76s if you ask it to. That will get you a starter gear of 2.76 x 2.74 x TC ratio of 1.15 = 8.7 = adequate for you. It will cruise at about 2250/65. With a good tune and a well-tuned V-can that should get you well into the 20s mpg.Well into.
You will have to know the exact compression ratio,and/or the average cylinder pressure, to pull this off. If the Dcr gets too high, you will be buying premium gas. Do it right and it will be dynomite, on 87E10. Mine sure was.
BTW, dont be afraid of having to run Premium. If it costs 10% more and drives you 10% further, then the cost per mile is a break-even.
And consider this, The engine may only need 93premium under full-load conditions. It might cruise on 60octane.
..............................Tune it.........................
 
I agree with what many others have said,raise the idle to 750-800rpm and work on your ignition timing,do some carb tuning and that should run fine. i have run alot more camshaft in a 340 with a reasonable idle at 800rpm and tuned right the mandatory emissionscheck was a joy,the inspector was impressed how clean it was running.
 
skep419 said:
if you dont have a light and at the moment you could always just turn up the initial until it runs smooth at idle. back down the idle to 850 limp around till it gets warm. shut it off in your driveway and see if it starts again. if it kicks back, back it off until it starts. limit the mechanical to around 34 and let her eat.
Click to expand...

How is he going to know what the total is with no light? This is a recipe for disaster. Don't play with the timing without a light.
 
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