1987 Monte SS Carb swap

[intraspec676]

Hi, I hope someone can help
I replaced the original Rochester Carb on my 1987 Monte SS
with a Edelbrock 650 carb not sure what to do with the vaccume
lines had to take off the egr and block it off I plugged a couple of the vaccume lines and hooked some to the carb but now it pops through the carb every time I try to accelerate.
What did I do wrong???
Can anyone help?
Thanks.

 

[85 Cutlass Brougham]

A picture is worth a thousand words. I would really have to see what you did to tell you what is wrong. I had a similar problem once, and it was because the AIR system was not sealed and was drawing air in through the exhaust and leaning out the cylinders. Oh, and there is no "e" in vacuum.

 

[intraspec676]

I will take a pic and send it to you .
Maybe it's leaking from the EGR block off plate I put on.
Could that cause the problem?
Thanks for the spell check :^0
Thanks...

 

[85 Cutlass Brougham]

If it is leaking at the EGR valve, it would cause the problem you are describing.

 

[megaladon6]

did you tune the carb or just slap it on? with a timing light, make sure the ignition advance is still working, if using the stock ECM controlled distrubutor. are the vac lines hooked up according the the original diagram and edelbrocks manual?

 

[85_SS]

If you want to get rid of the stock CCC carb, then you need to ditch the entire CCC system, which includes needing a new (old style) vacuum advance distributer.

 

[megaladon6]

actually my dist works perfectly fine with out the carb. i have the ECT, knock, and baro sensors hooked up. the engine responds perfectly in all areas, including sharp throttle changes. i am going to hook the MAP sensor in soon and see what happens though.

 

[intraspec676]

I figured out the problem since I just bought the car and the carb was apart I put the Edelbrock on all the vaccum line were correct.
Before I changed the dist or anything else I checked the Firing
order and sure enough the previous owner mixed up the wires.
It runs perfect now.
Thanks for all the info.

 

[85_SS]

actually my dist works perfectly fine with out the carb. i have the ECT, knock, and baro sensors hooked up. the engine responds perfectly in all areas, including sharp throttle changes. i am going to hook the MAP sensor in soon and see what happens though.

You should be getting at least a couple codes with the CCC carb missing (TPS, MCS, likely 02), and the distrubuter is not advancing properly, but rather refering to a standard "limp home" mode table. Without input from the TPS, the computer doesn't know what to do with the advance curve. If you eliminate one component, you have to eliminate everything as it is no longer working properly. It will still run as you have experienced, but you are not getting optimal performance by a long shot.

 

[megaladon6]

limp home mode is a set advance number. it won't vary with load or speed. that's NOT what is happening with mine. the advance curve is working fine and has at leats 15* of varience. if it was in limp mode the engine would run decent at idle and low load/low speed only. not when spinning the tires or at 6k rpm.