Ad on TV for Holly Fuel Injection on Older Engines

[LBJ]

I saw an ad for the Holly Fuel Injector system for older cast iron engines and wondered if it is a good thing. I suspect it would run at least $1K or more, but man, that would be great for an old 350 4 barrel that gets lousy gas mileage. Anyone tried this mod? Thanks, LBJ

[mongocanfly]

Just me but I'd go LS before I'd drop that much on top of a small block...It may be a good setup...they've been around for a while....

[LBJ]

Hey Greg, yep, I'll agree with the LS swap. But, that swap is a LOT of work! I am really just thinking about the FI setup now. The old 350 runs pretty good anyway. Never was much on gas mileage. Ha

[mattfranklin]

Depending on how the new system is set up it might get you 10% better MPG and better driveability. If your fueling system is pretty screwed up to begin with it might get you 20%.

So you might go from 10 MPG to 12 MPG. Figure out how much you drive and see if it will pay off in a few years.

10k miles per year @10 MPG
= 1000 gallons
at $3/gal that's $3000 per year.

10k miles @12 MPG
=833.3 gal
at $3/gal that's $2500.

So at best you're saving $500/year.

Three years of that would be $1500, so the system, all expenses included, should not cost you more than $1500.

If it costs more then don't buy it.

There are fancier ways to analyze this, with time-value-of-money, blah, blah, blah, but this puts you in a good ballpark for estimates of short term projects.

If you drive less than 10k miles per year then ratio the benefits down.

[95 S_Trucker]

The improved cold start ups and self tuning at altitude changes are the biggest pros in my book. You may get a little bit better mileage, but I wouldn't expect it.

[LBJ]

She sits in the garage most of the time, sad to say. I try to drive her once a month at least. But sometimes it's not even that often. So, gas mileage really isn't an issue since I rarely go more than 10 miles per outing and less than 500 miles a year at the most. I converted the A/C over to 134 but it leaks out every year. Fall/Winter/Spring is the best time to drive her. So, I guess I'm basing performance on my 2004 Vortec 295 HP Silverado. It runs so fine, I'd love to have that engine in the '77. But, back to reality, the FI is too costly for my old truck.

[bluex]

I swapped mine to a sniper earlier this year. Ive taken it to a show in mrytle beach the past two years. With the carb (edelbrock 1406) I got about 15.8 mpg over that trip. With the sniper I got 17.2. I have added timing control now and trying to dial it in better but it's not cheap by any means. I'm around 24-2500 all in at this point. I have about 3500 miles on it now. It did the full long haul on the power tour with no issues.

1978 C10 .060 over 350 stock except I used flat top pistons, a summit K1104 cam, stock reworked heads, edelbrock performer rpm intake, and 3/4 length headers. Its backed by an NV3500 (.73 OD), 3.73 gears and a 30.5" tall rear tire (295/45/20).