Looking at going back to a carb!!

[MJJ]

why not take it to a professional and have a custom dyno tune?

[eschaider]

Originally Posted by MJJ

why not take it to a professional and have a custom dyno tune?

^^ This is your correct fix.

You are clearly unfamiliar with how to tune an EFI system so go to the professionals and stop wasting time and money. The EFI will outperform a carb in every aspect you can measure.

On the other hand if you want a carb, for what ever reason, go buy one and put it on like we all have done for decades. Smaller ones perform better at low engine speeds and bigger ones perform better at high engine speeds.

Use a wideband, as has already been suggested, and dial it in. You will surrender some drivability, mileage and cold start manners but it will work just fine - like they always have.

Sell your EFI to someone who wants and knows how to use one and repurpose the dollars for something else on the car.

Ed

[olddog]

Jerking the intake off and plopping a intake and carb on is easy, but what about ignition, fuel delivery, and wiring harness?

Assuming you have a decent EFI system, it should be controlling the ignition timing and fuel pump, too. Perhaps the fan and speedometer, as well. The EFI fuel pump is putting out way too much pressure for a Carb, so that has to be changed. If it is a return type fuel system, you should remove that. Odds are you are going to have to buy a distributor. When you remove the EFI wiring harness, you need to provide for just about everything that it connects to other than the fuel injectors, and sensors.

Then you are going to need to tune the carb and get the timing curve set up for your engine. As stated to do it right, you need to use a wide band O2. Many don't and put up with the stench and leave 50 Hp on the table. Without the dyno you will leave more Hp on the table do to the timing curve not being dialed in.

Not hard to drop a grand on intake, carb, distributor, fuel pump, etc. Then another $500 to get it tuned.

Or

Take the EFI to a good tuner. He more than likely can fix it and tune it right for under a grand.

[lippy]

Originally Posted by olddog

Not hard to drop a grand on intake, carb, distributor, fuel pump, etc.

That's an understatement. I'm using a carb (Holley HP Ultra 950). The cost of the carb + intake + fuel pump + fuel lines + fittings + filters + regulator is almost $3k. This is good stuff (Aeroquip, Aeromotive, etc.) but I was shocked how quickly it added up. And you will need to replace most of it.

I agree with the folks who said fix what you have.

[vector1]

Originally Posted by lippy

That's an understatement. I'm using a carb (Holley HP Ultra 950). The cost of the carb + intake + fuel pump + fuel lines + fittings + filters + regulator is almost $3k. This is good stuff (Aeroquip, Aeromotive, etc.) but I was shocked how quickly it added up. And you will need to replace most of it.

I agree with the folks who said fix what you have.

Lippy, if you haven't used the 950 yet you might want to trade it for a 850, the 950 is reported to not pull as good a booster signal which could make it tougher to tune and the 850 flows around the 950. I think blykins had trouble tuning a 950 on the dyno and switched it for something else.