283 combo mismatch

[Mike Allred]

Hurt the 406 in my 3,000 lb. El Camino and dropped in the 283 to finish the points season. I had to use the tight 406 converter behind the 283 and now the poor car can't get out of its own way until 5,000 rpm. It then screams to 6,800 plus, shift, falls on face, then pulls hard again when reaching 5,000 rpm. 283 is 9:1, stock 305 heads, .490/.510 and 236/246 @ .050 solid cam, Performer RPM with 600 DP Holley, PG trans, 30" tire, 4.56 gear. This thing is gutless with the tight converter.
1. Would a seconday carb help?
2. Advance the timing to the moon?
3. Cheap loose converter?
4. 6.00 gear?

Seriously, just want the motor to run semi-consistently through the winter until big motor is repaired. Don't wanna spend a lot of money...

How do I get a little motor to pull from 3,000 rpm cleanly with all the wrong parts?

 

[Hitman]

Stack a ton of gear and a 3-speed in it. Trying to get a 283 to get any appreciable stall speed from a convertor is not going to be "cheap". That's basically a new, custom convertor, and 8" convertors are $900 and up.

 

[LS6 Tommy]

A vac sec would help the bottom end a bit, but it won't cure the mismatch.

Tommy

 

[Mike Allred]

I bumped timing from 39 to 45 degrees and it helped a little. I dust off a 750 vacuum secondary carb and see what happens. Redneck performance sells a variety of high stall converters for around 325 bucks. I had one, then sold it when I thought I'd never have the 283 in the Elky... Stoopid move.

 

[lurchsmalibu]

smaller camshaft?

I had a mild 273 with stock everything else in a MOPAR growing up and it was pretty stout for the small cubic inches. I had the comp cams with a 480 lift and 2800-7200 RPM's in a fun manner.

 

[Damon]

Lock out the timing completely. You aren't spending much time down in an RPM range where centrifugal advance matters anyway. Then tune it- carb, timing, etc. Get the most out of it without spending a ton of bucks.

And don't be afraid of shifting it higher than 6000. If it's just coming to life at 5000 a 6000 shift is leavign the party too soon. If it won't rev over 6000 I'd wonder about the valve springs being adequate for the cam. It's a lot easier for mediocre heads (like those 305s) to fill a smaller cylinder at elevated RPMs, but the stress on the valvetrain is the same as RPMs climb, regardless of displacement.

If you want to change parts that cost real money I'd do the converter. Won't make it run like the 400, but at least you won't be dealing with the miserable low-stall soggies off the line and after every shift.

 

[Mike Allred]

Damon, timing is locked out. Went to test n tune last night and the only change made that showed promise was leaning the carb. It has a 600DP Holley with 66/73 jetting and I went to 71s in the back and the car began running strong from 4500 on. It picked up a tenth over previous runs. I jacked the timing from 38 to 48 with little change so I locked it down at 42 and forgot it. The car's reaction time is good -- I'm able to shallow stage the same as the big motor. The early transition to the main jet is soggy so maybe lean is what it needs. The combination of little motor, 9:1 compression, cam that's probably a little too big and tight converter may need a leanish mixture to ignite easily and build cylinder pressure with spinning the motor excessively. Theories...