Don't think I can go any farther with it

[TrailBeast]

So I drive this 73 Dart everywhere I go, and that is a LOT because I have to go onsite for most of my work.
Then on weekends I drive it just for the fun of it, so I need to keep it reasonable for daily drivability and fuel economy for now.
I seem to be at kind of a stand still on the engine because of this limitation.

It is a stock bottom end 318 but I have already added,
600 CFM Eddie carb with full size chrome air cleaner
Dual plane Performer intake
1 5/8 tube aluminized headers
2 1/2 inch aluminized dual exhaust (X piped)
Flowmaster 40's
Mini starter
HEI ignition
8 mm Accel yellow silicone wires
NGK V power plugs
Fabricated aluminum valve covers with chrome caps
Fully automatic electric cooling (keeps it under 210 on hot days)
26 inch two row radiator
190 thermostat

My future plans are to pick up an LA360 and have the heads done and milled to run on the 318 while I take (probably months) to do the 360 bottom end, then drop the 360 shortblock in and put the heads back on it.
(Obviously I'll be changing the flexplate and converter at the same time)
I already have a small pile of stuff I can't use yet till the 360 goes in.
(MP cam and lifters, double roller set, and a few other things)

The car runs great, and is extremely reliable the way it is, but can you all think of anything else I can do for performance besides tearing into the bottom end and limiting the fuel I can run or the fuel mileage?
I get about 14 mpg as it is now.

Thanks

 

[lurchs66cuda]

What rear gear ratio and transmission?
What specs on the cam?
What are your plans on the 360 as for performance level do you want?

 

[godfatherofchry]

I had a 318 in a 71 dodge pu.it bernt a valve and wile I had the heads off I pocket ported them and gasket matched and tapered the runners..then had them milled 40 and put it back to gether..it picked up 4mpg and ran like a raped ape..and there wasn't a 350 or 351 that could get close to it.......hope this is a help...........Artie O and I have to ad that thing went over 300.000 and was going storng for the guy that bought it for another two yrs tell It got totaled...

 

[BillGrissom]

You have time to kill since your engine is currently running fine, but you are thinking of installing 360 heads as an interim until you change the block to match.

To get good mileage and performance, the main concept is "small + large", in several areas:

High lift cam, w/ Rhoads leak-down lifters so it acts small at low rpm

Spread-bore carb (Thermoquad or Quadrajet) - tiny primaries for good mileage (better atomization and distribution), and monster secondaries for max flow. Multi-port injection is as good or better, which is why all modern engines use that (if not direct injection).

Intake - Offenhauser followed this idea with their unique "Dual Port" intake, with small runners off the 4 bbl primaries and separate bigger runners of the secondaries.

4+ speed tranny, w/ low gears to get off the line and high gears to cruise with good mileage.

 

[67Dart273]

If you want to take the trouble to put (maybe a budget regrind?) cam in? Just don't go too big

I have to say I'm flat AMAZED at how well my 67 ran

Stock heads/ pistons/ block mid 70's smogger used engine

Headers (coming off) performer, had 600-650 Ed, now have EFI

Mild "340 ish" cam

3.7X rear gear, tires I run give me about 3300 at 70.

"VERY" snotty at that speed.

 

[TrailBeast]

What rear gear ratio and transmission?
What specs on the cam?
What are your plans on the 360 as for performance level do you want?

A999 trans.
The rear needs to get changed so I never bothered to see what gears, but they are pretty high (80 in second is easy enough)
The 360 would get the cam and pistons later down the road, but the milled 360 heads should wake up the current motor a bit without sacrificing fuel economy I think.

I drive it on the freeway quite a bit at 70-85 for hours at a time, so I can't change much there unless I get a different car for that.
I'll probably just have to settle for working on other things than the motor for now.

I had a 318 in a 71 dodge pu.it bernt a valve and wile I had the heads off I pocket ported them and gasket matched and tapered the runners..then had them milled 40 and put it back to gether..it picked up 4mpg and ran like a raped ape..and there wasn't a 350 or 351 that could get close to it.......hope this is a help...........Artie O and I have to ad that thing went over 300.000 and was going storng for the guy that bought it for another two yrs tell It got totaled...

It helps a little bit since I am thinking to just swap the heads for now, and leave the 318 in it.
Better breathing couldn't hurt.
Thanks

You have time to kill since your engine is currently running fine, but you are thinking of installing 360 heads as an interim until you change the block to match.

To get good mileage and performance, the main concept is "small + large", in several areas:

High lift cam, w/ Rhoads leak-down lifters so it acts small at low rpm

Spread-bore carb (Thermoquad or Quadrajet) - tiny primaries for good mileage (better atomization and distribution), and monster secondaries for max flow. Multi-port injection is as good or better, which is why all modern engines use that (if not direct injection).

Intake - Offenhauser followed this idea with their unique "Dual Port" intake, with small runners off the 4 bbl primaries and separate bigger runners of the secondaries.

4+ speed tranny, w/ low gears to get off the line and high gears to cruise with good mileage.

I'm not considering anything that involves the bottom end or valvetrain in the 318.
The 360 will get the bottom end and cam later.
Automatic with OD could happen, but for a daily driver I want to stay with the auto. (Drove sticks for a loooong time and kinda tired of doing it all day.)
The plan was to get everything alse ready for the 360, but I'm kind running out of things to do now.

If you want to take the trouble to put (maybe a budget regrind?) cam in? Just don't go too big

I have to say I'm flat AMAZED at how well my 67 ran

Stock heads/ pistons/ block mid 70's smogger used engine

Headers (coming off) performer, had 600-650 Ed, now have EFI

Mild "340 ish" cam

3.7X rear gear, tires I run give me about 3300 at 70.

"VERY" snotty at that speed.

What do you mean by "snotty"?

 

[Revhendo]

Not really a budget install, but a good one is the 200r4 conversion. You were changing the rear end already (at least that's what I inferred from your post), so you could go with a steeper gear for off line performance.

 

[TrailBeast]

Not really a budget install, but a good one is the 200r4 conversion. You were changing the rear end already (at least that's what I inferred from your post), so you could go with a steeper gear for off line performance.

Yea I thought about that but would probably do the A500 if I did.
Seen the insides of too many 200R's

 

[Revhendo]

Yea I thought about that but would probably do the A500 if I did.
Seen the insides of too many 200R's

Bwahahaha!

I've seen some pretty stout 200's. Isn't the 518 supposed to be stronger? (Not too qualified on the Mopar OD's).

I like the idea for better breathing for an initial step.

 

[TrailBeast]

Bwahahaha!

I've seen some pretty stout 200's. Isn't the 518 supposed to be stronger? (Not too qualified on the Mopar OD's).

I like the idea for better breathing for an initial step.

The 200R needs a lot up upgrades to make them tough enough, as sun gear shells and some of the drums and pistons are stamped steel.
I like the cast drums and pistons of the A500 (or 518) a lot better.
Also don't care for teflon sealing rings, and would feel a lot better about interlocking cast rings.

I also don't like the overdrive being in the converter.

Chk out the drums differences stock and see which design you would trust more.

The first one is the 200R4 and the second is the A500
These are the parts that all the engine's power goes through.

 

[71Scamper]

The 200R needs a lot up upgrades to make them tough enough, as sun gear shells and some of the drums and pistons are stamped steel.
I like the cast drums and pistons of the A500 (or 518) a lot better.
Also don't care for teflon sealing rings, and would feel a lot better about interlocking cast rings.

I also don't like the overdrive being in the converter.

Chk out the drums differences stock and see which design you would trust more.

The first one is the 200R4 and the second is the A500
These are the parts that all the engine's power goes through.

Not to rehash old stuff but I was searching through for information and came across this thread. I just wanted to make a small correction. The overdrive in the 200-4R is gear not converter. The converter can be locked to allow for no slippage adding in the fuel economy department when on the highway. IIRC, Chrysler 4 speed OD transmissions also have a locking converter. and both can run non-lockup converters if so desires.

 

[ntsqd]

Since it's been dredged up, what ever happened with all of this?

Was it me:
OD auto of your choice
rear axle gears that work with the OD and tire size to put the engine at its most efficient RPM at your normal cruise mph's
hydraulic roller cam because they have more area under the lift curve and reduce friction
As much DCR as pump fuel will tolerate
EFI, even if only a TBI type system.

 

[TrailBeast]

Since it's been dredged up, what ever happened with all of this?

Was it me:
OD auto of your choice
rear axle gears that work with the OD and tire size to put the engine at its most efficient RPM at your normal cruise mph's
hydraulic roller cam because they have more area under the lift curve and reduce friction
As much DCR as pump fuel will tolerate
EFI, even if only a TBI type system.

It was'nt actually something I was doing at the time, just thinking out loud.
Good suggestions though.

I would like to swap rear ends pretty much before I do anything else.
Probably going with a Jeep Cherokee disc brake 8.8 locker.

 

[ntsqd]

I'm going to guess that an 8.8 will come with 3.73's, which IMO are just about as good as it gets for all-aroiund use. The set in the Ford 7.5 under my Valiant is working very well with the .72 OD ratio in the T-5.

 

[TrailBeast]

I'm going to guess that an 8.8 will come with 3.73's,QUOTE]

I think you are right.

 

[805moparkid]

have you thought about a good modern converter from say Edge racing? Will be alot more efficient all over the place, you should see mpg/power gains all over.

Andre @ 805-277-7305 tell him Ed the slant guy sent you!