Hello all,
I got a new engine installed in my car. The new engine is a 350 performance upgrade that is supposed to have around 350 HP.

Well the thing is running extremely rich. The guy that did the engine swap for me said there is nothing he can do about it and is blaming it on the electric nature of the ccc qjet not working correctly.

He also put a distributor in and says the timing is set for 55 degrees at 3k RPM and that is the best he can do when the engine spec calls for 27 degrees at 3k RPM and 45 degrees total at 4500 RPM. So I don't know if this contributes to the problem or not. The distributor is vacuum based, the reason it was changed is that he claimed my stock distributor couldn't advance correctly for the 440 cam that is in my new engine.

So he says that since the distributor is disconnected the carb isn't mixing the fuel correctly and that is why it's running rich.

Can anyone give me any further insight on this, and tell me what I can do to correct the problems? I mean this thing is running so rich that I used up about 8 gallons of gas tonight in only 60 miles. Quite often when I stop at a stop sign or red light it will bog down to the point that it takes 2 to 3 seconds after lightly pressing the accelerator for it to catch up and actually start accelerating.

Oh, by the way the new engine came from cmengines.com, not the guy that did the install for me.

 

You need a new mechanic. The one who did this work is an idiot.

Put the original distributor back in and set the timing to 6 degrees base (ECM connector to the distributor disconnected). See how it runs then for a few days, adjust the timing more or less advanced by 2 degree increments if required until it runs well.

If he doesn't have your original distributor anymore, tell him he's buying you a new one.

There isn't a properly built SBC out there that needs more than 36 degrees mechanical advance. The cam does not, can not, and will not require more advance than that. Don't know what this "performance upgrade" engine is, but Vortec heads tend to require even less advance due to their increased combustion chamber efficiency.

Computer carb chips can be programmed, but really "needing" it is pretty rare. Jet may be willing to do a chip for you if you really want it. You'll need to give them your engine & cam specs, and they'll probably want to know a little about the car as well (stall, gears, weight, etc.).

 

Hey thanks for the reply, and yeah I'm starting to realize that the guy isn't the best around.

He has done a bit of work for me and has been helpful but he just isn't very good with computer stuff. So I wont say anything to bad about him but I'm definitely not happy with the results of this engine swap.

I have the original distributor, but if I put it on with out the ECM connected, it's not going to advance the timing any when accelerating is it? Wont that cause less than optimal power due to lower spark and slower fuel burn?

Maybe I have some things mixed up I don't know a lot about these things just what I've read.

I am thinking about doing away with the ECM completely and getting a non computer controlled carb to put on the car. Looking at specifically a reman quadrajet from summit racing as it looks like it is pretty similar to mine except without the computer control.

As for the "performance upgrade", I don't really know what all makes it a performance upgrade besides the cam. It has a 440 cam in it, I don't recall the durations off hand though. I imagine the other stuff in it is just upgrade to handle more power. It's supposed to produce around 350 HP.

 

Why can't the original one be connected to the ECM? Can my good one be connected to test?

Don't drive too much like this. We don't want to wash the cylinders. I may come to you unless you're close by.

I thought the 45 was a typo for 35? That would make sense.

 

The original one was advancing to 35 degrees while idling according to what Brock (the guy doing the work) said. That is why he said I needed a vacuum advance because the ECM couldn't read and adjust for the engine properly.

The 45 was not a typot it is what the spec sheet from cmengines.com says.

All the connections for the ECM are still there afaik, nothing was supposed to be cut to install the new one.

As for distance, I'm probably about 10 miles from you I think.

 

Must be their typo.

I'll get with you in the morning and see what we can do.

I've got the berli torn apart in the garage and we can try the dist that came off it.

 

Ok, my fault I had the number wrong. Just got home and looking at the sec sheet again and it says 14 degrees @ 700 rpm, 27 degrees @ 3000, 30 degrees total @ 4500 rpm.

Further details on the motor and cam:

OE heads, rods, and block, Federal Mogul hypereutectic pistons, Perfect Circle moly rings, brass expansion plugins, premium main & rod bearings. Performance valve springs, pushrods, hydraulic lifters. Camshaft info: flat tappet cam, .440" lift 270/224 duration. 9.5:1 compression ratio.

 

if he left the CC quad on there, then you cant run a vacuum advance distributor. if he took the CC quad off and replaced with it with a non CC quad, then the vacuum advance dizzy needs to stay.

running a CC carb with a vacuum advance dizzy results in a car that doesnt run right.