Easy things to make it peppier? 68 Newport

Biggredd2069

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Have a rebuilt 383 68 newport with a fitech fuel injection. Had stock torque converter replaced a few years back, missed opportunity there. Stock rear end. The car is heavy. I just always call it a cruiser, not a race car. Which I don't want a race car necessarily but I would like to maybe make it a little peppier. Any easy things I can do to make that happen? I can't spin the wheels out easy, would maybe like it to just be more responsive on the throttle. It's kind of laggy.
 
First thing is to verify the ignition timing is correct. Yes, the 383 2bbl with 2.76 rear gears will lay some rubber, just not a giant smokey burnout. But will respectfully raise the nose as it leaves, too. The stock (1800rpm stall, or thereabouts) converter is needed as it is "tight" for best highway fuel economy. Tighter than similar Ford or GM cars, with better off-idle throttle response.

At your altitude, you can add another 2 degrees BTDC to the OEM timing setting, which can compensate a bit for your higher altitude.

Of course, do you have the EFI configured to control both the mixture and ignition timing? Or just the mixture?

Personally, I would expect the EFI to have very sharp throttle response off-icle. Perhaps you need to contact FiTech for guidance.

Yes, the car is "heavy", as our '66 Newport Town Sedan 383 2bbl has a title weight of 4100 lbs, being probably closer to 4400lbs "wet with driver"? When the car was new, it was credible in performance, but with only about an 80mph 1/4 mile speed for the 383 2bbl. 383 4bbls and 3.23 gears were quicker and faster.

The OTHER thing is . . . from a dead stop, only punch it about 1/2 throttle initially, to get things moving, then at about 25mph in low gear, go the rest of the way to WOT and the higher 1-2 shift point. If you try to go immediately to WOT, it WILL bog the engine and lose any vac advance in the distributor at the lower rpms. By observation, the 383 2bbl distributors had a pretty good advance curve in them, from the factory, usually with a total of about 36 degrees of total advance.

So contact FiTech for any tweaks to the program and then learn to drive the car to extract its best acceleration performance.

Enjoy!
CBODY67
 
Nitrous. Problem solved. Lol. It was a 4 barrel car, but fitech now. It's a fuel mixture only setup, doesn't adjust timing. I do have it the running a little sharp so think I have that covered as much as I can. I think the fitech is relatively responsive, maybe I just want a little more torque in general.
 
I agree with timing the engine for what it wants. Use a vacuum gauge to find the max initial your engine wants. My 67 Coronet wagon 383 4 bbl, 727, 2.94 gears, 275/60r15 rear tires. It gets up and goes very well and I love the gears, but I am also not wanting to do tire burning departures. Good videos here at Tall John's fun shop.
Timing in the wagon is an initial of 20 deg, 36 total with vacuum advance for cruise. I use the FBO timing curve plate. How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races
 
With what you've got, no small adjustments will get "more torque". Provided the ign timing map is as good as it might be. Otherwise, you'll need torque multiplication approaches.

A '68 Road Runner-type converter (about 2100 stall speed, 10.75" diameter), 3.55 gears (marginal), 68 Road Runner 383 HP Cam, etc. You could always do a 452 stroker motor.

CBODY67
 
Have a rebuilt 383 68 newport with a fitech fuel injection. Had stock torque converter replaced a few years back, missed opportunity there. Stock rear end. The car is heavy. I just always call it a cruiser, not a race car. Which I don't want a race car necessarily but I would like to maybe make it a little peppier. Any easy things I can do to make that happen? I can't spin the wheels out easy, would maybe like it to just be more responsive on the throttle. It's kind of laggy.
Drop in a 440. Stop dumping money into the 383.
 
A quicker ignition advance helps a lot. (as long as you don't go too far or too fast)
 
Besides insuring the timing and carb are tuned, change to 3.9 gears if you don't need to commute frequently on the FW. The 383 will like and handle the rpms just fine, only down side is gas mileage will suffer.
 
Your 2:76 gears are great for the highway but not so much for getting off the line quickly. 3:23 gears would help. Dual exhaust would also help if you don't already have them.
 
If the cars worth it to you, go all the way.

DSC07291.JPG
 
Ya, you'll feel the gears in the seat of your pants, and if you have a set ready to go, just an afternoon to change out. I drove a fare amount last year on a 3.9 set up, about 3k rpm on some FW driving at 60mph and my 400 BB did fine, of course it will depend on your tire size for your rpms.
 
I've already gone down the rabbit hole committing to this engine. I don't necessarily need a majority more power, just making the power it does have more usable.
 
Removing whatever weight you can will help. What's in the trunk besides the jack and spare? Can you use an aluminum intake which is lighter than OEM? What about a cooler thermostat to lower the temperature under the hood (and therefore make your intake air cooler and denser) without fouling the plugs? Since Parker is over a mile high in elevation, anything you can do to make your intake air denser and get more air into the motor would help. Also, with a cooler motor, can you run more timing? Would a colder heat range on your spark plugs help you run more timing? What octane gas are you using?
 
I do have a aluminum intake as of recently. Big weight difference for sure. Jack and spare removed but I have subs in the back. I could make air flow better to the cleaner.
 
The best and easiest bang for the buck upgrade you can make if it’s running right is a lower gear. 3:23 is a good all around ratio. You will definitely feel the difference.
 
I have the 400hp fitech. It's been a pain in the *** for years but just recently dialed it in. Had an issue with the fuel pump no one could figure out. Going to buy a firm feel steering gear box next month and maybe winter project update those gears.
 
I have the 400hp fitech. It's been a pain in the *** for years but just recently dialed it in. Had an issue with the fuel pump no one could figure out. Going to buy a firm feel steering gear box next month and maybe winter project update those gears.
I wouldn't go over 3.23 gears.
 
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