EFI vs Carbs, This will start a crap storm Options

[ellisor3]

I inherited a pair of Zenith carbs on my six conversion I purchased last year. Yes that is Zenith, not PMO or Weber-Zenith. The set-up was done by Motor Scheister several years ago by the PO (IMG:style_emoticons/default/sheeplove.gif) . I have been working with these for the last month to get them tuned and sync'd. I can not for the life of me get them right. They will idle ok but at acceleration they backfire or vise versa. They were rebuilt at AA back in the summer, but that did not solve the problem. No exhaust leak, new plug and the same problems. Some adjustments don't have any effect at all on the set-up. (IMG:style_emoticons/default/headbang.gif) I am at my wits-end on these damn things.

Anyway my delima is whether I should replace the Carb's with PMO or Weber or simply junk the carb idea and move to EFI. Here are some of my considerations, but wanted some I may have missed.

1.) Cost of Carb PMO's $3500
2.) Cost of EFI ??
3.) Ease of adjusting/reliability-EFI
4.) I live in Florida so high humidity-EFI??
5.) Fuel efficency-EFI
6.) Acceleration-Wash??

Thanks for your input

[ahdoman]

We need a little more info to help...
1) What size carbs?
2) What size engine and ignition details?
3) Was the engine originally injection and carbs added later?
or...
4) Was the engine built for carbs?
5) Are they backfiring in the carb or through the exhaust?

[ellisor3]

We need a little more info to help...
1) What size carbs?
2) What size engine and ignition details?
3) Was the engine originally injection and carbs added later?
or...
4) Was the engine built for carbs?
5) Are they backfiring in the carb or through the exhaust?

Sorry should have added this in the beginning

The Carbs are 40's
Engine is a '78 3.0, I have not checked the ignition
It looks like it was set up for carbs, no evidence to say otherwise.
The poping is coming from both the carb and the tailpipe, but not leaks that I can find.

Thanks again