suggestions for my 340?

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carrmann

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I have a 73 duster 340. Not sure what my gears are... probably 3.73 or lower (3.9 etc), hard to say with the small tires on it. From what the previous owner told me, it has a MILD cam in it.. and a 600cfm edelbrock carb. otherwise its basically stock. not sure on mileage etc. etc. either.

I would like more hp out of the car. Its peppy, but not what I would like it to be. I'd like around 350 to 400hp. This is on a budget, so i want to keep it under about 2k$. :newb:

What all would I need to get there? CAN i get it there with 2k$? :blob:

not sure if its a numbers matching block or not, or even if its a 73 motor. I just know its a 340. :violent1:

Thanks
 
a bigger cam, some head work and headers would be a good start.........if it's an automatic you'll also need more stall speed in your converter........
higgs
 
im assuming this motor has low compression.

what about intake manifold/headers/cam? that should keep me below 2k$. I'l probably be able to do more to it later, that sjust my current budget.

I dont want to sacrifice much driveability, so nothing crazy. A small increase in stall speed possibly.

what heads are good? I was looking at the smaller CC edelbrock performer rpm heads to bump my compression a little, plus better flow.
 
What intake do you have now?
What gear ratio is it for sure?
Auto or manual?
What is your compression ratio?
 
Intake wise, a Stealth or RPM
Carb 750 cfm, Holley or Edelbrock
Headers from Summit racing $150
Summit racing exhaust $223 for a 2-1/2 system with mufflers
A complete cam kit, not just cam and lifters but the whole deal done right is about a tick over a grand.
Just a cam and lifter and spring set is about $460 give or take.
 
intake? stocker. so I dont know lol.

engine bay...
IMAG0118_zpsaf9b9d36.jpg


gearing I can check once I can jack it up and see manually check (previous owner was unsure). it runs about 3500rpm doing appx 67mph (speedo jiggles a little) down the highway in 3rd. tire height in rear is 215/70/14 or 25.85". the sites online where I can input rpm, speed and tire height say it is a 3.9x gear.

automatic

Im assuming stock compression ratio for a 73 340 motor. I BELIEVE that is 8.8:1 roughly. It runs just fine on 87 octane.

how bad are the summit headers regarding installation etc? I DO have power steering. Will they still fit?

what does a complete 'cam kit' consist of? Im assuming rockers, lifters, springs, cam?

Thank you Rumblefish for all the assistance thus far!
 
Your brand spankin new at this huh?!
OK. Here we go.......

Your question of will they clear power steering is answered at the web site. Diddle your fingers over to Summitracing.com and use there super friendly search engine to look up a part and click on it to read up on it just incase there not for your car/engine combo.

The summit headers are a typical 1 size fits all header that are just like everybody else's 1 size fits all header. Clearances vary just like any other header as well as the quality for the fit.
Of all the headers I have used, the Summit and Headman's were equal in the excellence in fit a d clearances. But this statement does not vouge for them. I'm just saying MY Experiance with them was good.

While nearly identical looking headers from Hooker, Black Jack, cyclone and a few others I had but can no longer remember, have fit poorly.

As far as installing headers on your car, it is a near 100% "For sure" you will be super pissed off, run through the gambit of curse words and maybe in several different languages and, ill give it a 85% chance you'll make up new curse words along the way.

It is nearly impossible to raise the engine and car up high enough to instant hem and you'll scrape the nice finish off. During installation you'll scrape, scratch and cut your hands and knuckles open and
More likely discover a mystery cut via a mystery blood stain somewhere. You'll remove tons of parts without any real clearance for the part. I'll give it an 80% chance you'll need to modify the header via a hack saw and/or hammer to bent the tube in order to clear something.

After you have this installed, you'll have further fits of rage and dis-spare with modifying the OE linkage from the column with flipping the linkage and a cut and weld in some cases. or yet more fit running a some aftermarket Lokar cable system.

You may run into trouble on the otherwise AKA "The easy side/passenger side" with a possible lack of the OE angle oil adapter for the filter.

Once the headers are in and your sessions with the 2 doctors or finished, (1 physical, 1 mental) I ga e you the easy exhaust to install, which I have used myself. You'll need ethier a metal bladed circular saw or good aim with a sawzall. Super talent is required with a hack saw along with those muscles that you almost never use. Advil is your friend.

The exhaust system from Summit racing was easy to install and fit pretty darn good. It slips into easy other (the pipes) a d requires little trimming at the bumper.
 
Cam kits;

Cam kits come in various levels. They can be as simple as just a cam and lifter package or one that has everything you need and then some. The cam, lifter and spring package is the most basic starting from zero package I listed and doesn't cover all the bases that may need to be covered.

I suggest reading how to rebuild your small block MoPar as well as How to hot rod your small block MoPar. Also the factory has a book designed just for your w time that can be purchased on line easy enough.
It's called the engines book.
 
When it comes to gearing, the ring and pinion have there ratio stamped on the ring gear. I suggest that in case the last owner has no idea or you can not reach him/her, change the rear ends oil out for fresh oil. With the rear end tires off the ground and the front wheels chocked, place the trans in neutral and spin a tire to see the ratio stamped on The ring gear.

While this is a lot of work just to know 3 little numbers, rest easy to know that your also maintaining the car properly and increasing longevity with the fresh oil.
(You may need friction modifier if you have a sure grip Equipped rear, AKA, posi)
 
On your intake, if you were not so new, id scream at you!

Look at the intake!!!!!!!!!!!

Read what is up front on the intake!!!!!!

It may say "Edelbrock" on it.....

Is it steel? You don't know????

Find a magnet and check. ;)

I'll help out with stuff but I'm not here to school.
(I get paid to do that, seriously, I do :) )
Good luck and enjoy!
 
Oh! Just remembered, the best fitting headers are the most expensive headers by tti.
I suggest, when the time comes, grab a comets cam kit from co
P cams. They make it very easy with there kits.
Much the same for the intake. Summit racing has kits. You can call up summit a d talk to a rep on e your up to speed on things and order away. There very good with customer service and knowledge. They either adjust a kit or put a package together for you.
 
I didn't read most of rumble's post-- but I'm positive his advice is sound . You need to assist us with more detailed info-- you don't know what gears you have not sure about the engine-- but you want to go faster. That is one vague & expensive statement.

You need to find out what your car has in it, & then do some searches on this site-- lot of info already posted.

Your engine compartment looks clean-- shoot, I'm off today, bring it to Wichita Ks & I'll look it over(engine size/ rear end ratio, exhaust size)) & test drive it!! Then you can have a baseline for improvement.

for that matter take it to a local track, run it in the 1/4 mile & that would give everyone a baseline performance of this car. Lawrence
 
your going to spend more than 2k! unless you want to spray it!:read: what rob is really saying is LEAVE IT ALONE! lol, hey rob do they still make blackjack headers the alum. coated ones? lmao.
 
LOL. Im sort of new. Did 1 small block 360 about 13 years ago, and had a very experienced person walk me through it, so I dont remember much.

Pretty familiar with the trials/tribulations of installation though lol. I've done quite a few newer cars, for myself and others.

I may hold off on anything serious, and save up for some nice aluminum heads with headers at the same time, also averting changing springs so all I will need is a cam to go with that.

Seems my first step is an intake manifold/carburetor setup. Then I'll save for heads/cam/headers. The intake has no brand new, just firing order and some other numbers stamped on it... and yes it is steel.


just saw new posts while typing this:
I am planning on taking it to the track shortly for a baseline. I just bought the car, which is why I know very little about it (about a week ago). I know that right now sadly my srt4 would blow the doors off it, and Im wanting to fix that lol. :burnout: .

Sorry, I charge for test drives. Feel free to fly up though and maybe I'll consider it. :blob:

No interest in 'leaving it alone', but I will be doing tasteful stuff and not chopping it up. I thought about a custom turbo, but that would again turn into 'chopping it up'. I have considered spraying it (I've used i before on my dakota r/t), and I know that is pretty cheap hp.
 
There is a shorty headers, so there is another option. If it were me and on a budget, find out the rear ratio, pull the timing cover, see what cam is in there and go from there. If it's an aftermarket one bigger than stock, get the cam card and degree it in. Post what it is here and folks can advise on advancing or retarding it based on what it is and your use, gear, trans etc. Buy an intake and carb accordingly. If the cam is small, stick to a performer and 600cfm, if larger, then again, seek advice. Compression is your biggest stumbling block and a large cam will be a dog and even more so without the correct converter.

Also, hows the tune? There maybe some HP on the table with some added timing and carb work.
 
LOL! My posts were or should be take. In part jest with the headers though it is true on that there a pain to install.

Otherwise, yea, I was a bit long winded. Sorry guys.
 
not sure on mileage etc. etc. either.

best way for more HP from the same cubes is compression. 9.5:1 or 10:1 should give way more power than 8:1

that being said/// your best bet is to find another core somewhere. take your time do a new build getting help you need... a good machinist, your own research, people here.

end result will be a new engine with way more power and you will be sure on the mileage and newness.

it would be bad money spent if you put 2k into bolt-on mods that dont give you power you want and then the engine breaks down as well.


also this way, you can continue to enjoy the car now, drive it this summer and have something to look forward to that will do way better than bolt-on retrofitting stuff

just my 2 cents
 
My recommendation, as it doesn't sound like you've done a lot of work on carbureted/pre-computer cars is to start with tuning.

Modern cars do so much without any interaction from the driver or a mechanic, it's easy to forget about this stuff.

Start with the ignition timing. Judging from the orange box (ECU) on the fender, I'd say that it's probably an unmodified distributor with a stock ignition curve. Your engine would probably benefit greatly from a recurved distributor with higher initial advance and a faster curve. I'd also toss the orange box for a chrome box as the orange ones tend to be a little flaky.

I'm betting that the carburetor is pretty much untouched as well, but I know very little about Edelbrock carbs, so I won't start to try to give advice on tuning it. I'd leave it alone at this point and work on the ignition first.

There is a lot of info on this site as far as ignition tuning, do a search and you should be able to find instructions to set it up.

Start with the basic stuff first, you'll also learn a lot about how the systems work in the tuning process.
 
hm. was just offerend an 8 3/4 with small bolt pattern (2.76 pumpkin) $400, 340 needing to be built with crank/pistons (.030 over)/rods (comes with it all) for 700$, and jet hot coated headers for $400
 
your going to spend more than 2k! unless you want to spray it!:read: what rob is really saying is LEAVE IT ALONE! lol, hey rob do they still make blackjack headers the alum. coated ones? lmao.

Oh man Mark! LOL, yea! I had a set of those aluminum coated headers. They were a great coating. To bad it was the typical 1 size fits all ill design.

hm. was just offerend an 8 3/4 with small bolt pattern (2.76 pumpkin) $400, 340 needing to be built with crank/pistons (.030 over)/rods (comes with it all) for 700$, and jet hot coated headers for $400

IMO, it's all a little pricey. Bargin down the price with cash on ha d for all the parts.
 
agreed, on the pricey. Did some research, seems that way to me too. Said the headers were 750$ with jet hot coating. working on the pricing though.

would a stock set of 2.02 j heads with strong valve springs (good for .500" lift) do anything for my motor? Assuming its stock 8.5:1 compression and stock 1.88 heads?
 
The best way to go about modifying anything is to do the entire system. If you start tinkering with valvetrain stuff, go with bigger ported heads if you want more RPM, port match an intake with large runners, like the Edelbrock RPM, be sure to center the intake with a witness mark on the cylinder heads, before bolting it down. Don't trust the index dowels on the front and rear to go into the holes and make the runners perfect.

The camshaft changes everything. If you run another cam in it, the power range in RPM changes and you need to make sure that your stall speed is good with that range, as well as your rear gears.

There should be a tag on that differential that denotes gear ratio. If not, check the ring like rumble suggests.

Edelbrock heads are nice, but they aren't cheap and should go on an engine with good quench, good pistons and good compression, otherwise you aren't getting your money's worth.

J heads are open chamber. Some late X heads are the same, regardless of 1.88 or 2.02, the chamber shape is what counts most. Bigger valves only help when you have larger runner volume up to the carb, matched and centered.

You'd be better off with a set of aftermarket iron heads, than edelbrock stuff, or a set of true, closed chamber X heads.

One silly question, if you aren't certain of numbers on the intake, have you checked to see if you are running a 340? I wouldn't trust just cylinder head letters or numbers. That engine has been apart and out, by the look of the Chrysler Red paint on it.
 
Factory rear gear ratio was 3.21 for an 8 1/4 even in 340 cars. that is a very short tire and steping up to a 275-60-15 or even 225-70-15 (only need hieght not really width unless you like fat tires on the back) and 3.55s and sure grip will greatly help you.
Sure grip is for fun :burnout:

Also changing the intake to an LD340 or just an eddy performer will help as it is better than stock and is aluminium
 
How about a good set of heads ?
Either edelbrocks or the Indy LA-X
Both will raise compression not to mention flow .
 
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