1/4 mile times

This car is so far from its potential its ridiculous.

CEASE throwing parts at it immediately.

Horsepower isn't your problem. BUT, you are giving up a ton of it by not having the timing and jetting tuned in. Further, if you've got no tach you don't have any idea where you're shifting compared to the powerband. You really need a shift light. Dialing shift point is worth huge ET.

Time the thing in as recommended in this thread. Go to the track with a shift light and dial the jets (keep going up by 2 until you lose mph). Do the same thing every pass, don't get caught up in the heat of the moment. Or just buy a wideband. Then dial the shift point. Then you can fiddle with the timing a little again.

Maybe I missed it, but what tire? Is it on a slick? If you don't have at least an ET Street, there's something to buy that will actually help.

2.0 60' time is terrible. If you get the car to hook, it will go a lot faster.

The front end is going to need a lot of help getting up with that heavy big block installed. I'd recommend Afcos or a similar real adjustable front shock.

Do you have a front sway bar? If so, it needs to go.

Measure your front travel. You need 5" or better.

Is the battery in the front? Relocate it or go to a lightweight unit.

How hot is the motor when you're running down the track. Hot oil is worth ET, but a hot intake is bad news.

Is it aligned? Are you going straight down the track or is it moving left and right?

AFTER you get all that figured out, for a converter I vote for Lenny at Ultimate Converter. Loads less than 2K.