I just recently put a new Edlebrock 600 cfm 4bbl carb on my LU5. the previous owner had a Holley 2bbl on it with an Edlebrock performer intake (using an adapter plate) I was just curious if this is going to make a significant difference in HP or gas milage. The A/C compressor had already been removed (wondered why the AC smelled and wasn't cold, until I looked ) I know a stock LU5 is listed at 160 HP. Other things still present ( I don't know if they matter) the charcoal canister is there (unsure it is being used) and the computer is still there (check engine light is constantly on) Thanks in Advance

 

Are you sure that the distributor has been changed too? If not your not even going to make stock power levels.

 

To be honest, I really don't know. Why would I be making less power with the stock dist? Is it a matter of needing a hotter spark? The car ran great with the 2bbl, and it sounds like it runs even better with the 4 (havent been able to drive it yet, still got a snow bank in front of it)

 

I'm really not knowledgable enough on those to explain farther, hopefully some one else jumps in and helps. I have just heard that if you change to an aftermarket carb on a computer controlled carbed car then you have to go to an older HEI to have the timing advance be right.

 

Probably the ECU is in limp mode which is not very optimum for performance or economy. So a 74-81 vac advance HEI would probably help performance and economy.

 

So what you are saying is that my ECU is currently only operating my distributer and thats all? Basically everything else has been striiped out of the car by the previous owner (cruise, A/C, crossfire F.I.) I would assume that the different trans (th350 w/ shift kit vs stock 200) would not be computer controlled. I am going to have to check if they already swapped distributers, as I have a small vac line going to the carb that doesnt look it belongs.

 

Yep

 

It isn't operating it right. You need a vacuum advance dist, not a CC one like you have now.

 

Well thanks for the info, I am going to check tomorrow where the patch in the vac line goes. Hopefully the previous owner changed it out already. If not, any recommendations on what to replace it with? I am not too sure on what I can put on this motor as far as compatibility.

 

If you have a hose running from the carb to the distributor, then it has already been changed.

Pretty much any older 305/350 distributor would work. I got mine from a 70's Camaro for my last car.

 

Ok thanks for the info, I checked today and it is the orginal CC dist. So that kinda sucks, hopefully I wont have much trouble finding one around here.

 

Make sure you get one that is not worn out, if the shaft flops around you will have problems...

 

So I take it the Cross-fire setup is long gone? If you do have it....I want it.

 

Yeah, sorry. I bought the car without it and they didnt give it to me either. Of course I cant complain, Ive only put about $350 into the car so far and paid $700 for it, so anything Ive got to do doesnt bother me a whole lot as there isnt a whole lot wrong with it. So as far as my original question, after I replace the dist. any guesses on HP?