Holley EFI

[Indy72]

I see a lot of people doing LS swaps on these old trucks and my question is,what about a Holley EFI set-up?

[Fitz]

Originally Posted by Indy72

I see a lot of people doing LS swaps on these old trucks and my question is,what about a Holley EFI set-up?

All of the throttlebody EFI systems (F.A.S.T, Holley, etc) are about the same---you're spending $1600 or more for an electronic carb. They resolve some of the issues that carbs have---cold start, tuning etc and for a mildly driven street rod or daily driver they're probably ok just more expensive than a carb. But, and this is a big but if you ocassionally drag race your truck, they fall way short in terms of the performance you can get from a closed loop sequential injection system. That said, you can spend almost as much on a closed loop system as you will for an LS1. It all comes down to economics...how much can you afford and will you be able to use the truck any differently than you do now.

Tough choice.

[78bronzechariot]

I have gone both routes. I have an LSx in my C-10 and a Professional Products powerjection (TBI hidden in a body that looks like a double pumper Holley) in my '78 Caprice.

I did the Caprice first about a year and a half ago. It was a two day project, just bolt the throttle body on, run the harness, run fuel lines and start it. Great if you want to keep a stock appearance, and not have to buy a bunch of parts (other than the $1600-1800 kit) and spend time engineering things to fit a different engine.The Professional products system I used is "self tuning". You just put in basic engine parameters, and drive it. It also lets you tune it on a fuel map like the Holley system does. In my experience, it took some fine tuning of target air/fuel mixture to get the most performance and fuel economy out of it. The only thing I don't like about it is that you have to let the fuel pump pressurize before you crank the engine otherwise it will start and die. Other than that, I am extremely happy with the results. Even with the 375 horse 350 with a healthy cam, it always starts and idles in any weather. When it had a Holley carb on it, it didn't even attempt to idle smooth (not that I expected it to.) It also has manners now. You can drive it like a new car, no matter how hard or soft you step of the gas it has nice smooth acceleration. Don't get me wrong, it still has that nice hot rod loping sound to the idle, but it is more fun to drive, and it increased my fuel economy slightly 1-2 mpg (from 10-12 to 12-14). It also increased the horsepower enough that I could feel the difference from the drivers seat.

On the other hand, I put a 2002 4.8 LSx out of a Silverado in my C-10. Which cost a lot more than $1600. Just the engine and harness was $1100 for a 60,000 mile engine. You may find a better deal than I did though (I know other board members have). Then there are all the other odds and ends to make a swap work, mounts, exhaust, hoses, harness rework, fuel system, etc, etc. Then you have the time factor. I spent a month of evenings and weekends doing the swap on my truck. However, you will be rewarded in the end. That truck literally runs like it came off the showroom floor as a brand new Silverado. Turn the key and it starts every time. It makes 275 horsepower (I think that's what an 02 4.8 is rated at) and gets 20 mpg (I did the 4l60e also, not necessary with the LS, but I would recommend it).

In the end, it just boils down to how much time, effort and money you want to spend, and what you want to do with the truck (daily drive, Sunday driver, etc) I would also consider the condition of you current engine, and if you like the way the truck drives now. I think there are pros and cons to either one, but I like both for the purposes I built them for.