Stock 350 Motor Accessory Upgrade

[BlackTomC]

Howdy folks. I'm currently in the process of restoring the interior on my Suburban, due to my ADHD, while I'm wire wheeling paint, welding in new sheet metal, staring an my shiny new floor, I can't help to think about stuff I can do to the engine to enhance it's performance slightly. I found a bucket of money laying in the gutter outside my house and decided since my IRA is maxed out for this year, and I've got plenty in savings, why not put my mechanic friends to work..

I was considering upgrading 3 things;

1 - Stock Intake - Edlebrock Air Gap Performer (Endurashine)
2 - Quadrajet (old faithful) - Holley Sniper TBI
3 - Distributor (upgraded from points) - MSD 6AL Kit

What do you guys think?

[Irish_Alley]

i would go with a cam, intake and maybe a holley 650 carb.

[BlackTomC]

Would I have to adjust the carb everytime I drove up north (Phoenix to Flag) few thousand foot elevation? That's what I'm ultimately trying to avoid, and choke issues...

[bd]

A properly set up carburetor will easily meter the proper amount of fuel from sea level to 10,000+ feet.  But you should tune the carb for the greatest performance at the elevation where the vehicle is most driven.

That aside, the greatest performance overall will be enjoyed by using an electronic fuel injection system supported by a suitable suite of sensors and a well-tailored BIN file.  Unfortunately, not all injection systems perform equally.  Self-learning EFI conversions generally offer a decent compromise between performance and fuel mileage, but some may better "self-tune" than others.  Continue to search the forums and FAQ sections of the various manufacturers for more information.  Temper the sales hype with what users have actually experienced.  If you have a local speed shop, introduce yourself, pull up a keg and sit around the cracker barrel for awhile.  Just keep in mind that your purpose with regard to a land barge is to build massive torque at low- to mid-RPM.  The engine doesn't need tremendous airflow to accomplish that, in fact, quite the contrary.  Most aftermarket "performance systems" are geared to enhance HP at higher RPM in lightweight vehicles.

If you are still running a conventional (points) distributor, converting to an HEI or MSD electronic distributor is a solid upgrade.  Any noticeable benefit of adding MSD CD ignition on top of a properly functioning electronic ignition system is debatable for a near stock engine configuration.

[bd]

Track the thread, "Holley Sniper EFI Anyone?" for developments....

[BlackTomC]

Sounds good.
Also Bd, the vehicle will be driven between 1000 and 10,000 ft elevation frequently (top of Mt. Humphrey's, especially during the winter for snowboarding and skiing). It's my dedicated camping vehicle, and I enjoy traveling to northern AZ all year long we are talking a massive change in elevation.

My primary goal is efficiency. Yes it will run just fine with both air/fuel ratios however it won't run at peak efficiency as I travel further north.

The distributor has been upgraded as well, I'm thinking of upgrading that once more, throwing a raised intake on it (not edlebrock) then plugging up the overpriced EFI to alleviate some headaches.

[BlackTomC]

I will heed your advice and find one of these shops you speak of as well, what you described is an area I know very very little about... unfortunately. However very willing to learn.

[bd]

Well, you are absolutely correct in that the convenience, performance, fuel mileage and versatility of EFI is hard to beat and surpasses carburetion.  If you plan on backcountry use, at the very least, carry a spare fuel filter and tools to change it.  EFI begs finer fuel filtration than carburetion and the filters require more frequent replacement.  The symptoms of a severely restricted EFI fuel filter can manifest quickly, catching you by surprise.