Chevy 366: Thoughts on Throttle Body Injection

[Ronnie]

At least a pertronixs unit to replace points . Then everything appears stock. My distributor had plenty of problems that changing to the HEI unit made a lot of sense.


By the way straightline steering found the right cylinder for me, Yay! so they are rebuilding it and will send my old one to them once I receive it. Thanks for the tip.

[RamRod4]

I converted a carb'd SBC 350 to TBI for a couple bucks and a trip to the junkyard. Find any mid-90's Chevy pickup with a 5.7 (5.0 will look the same and have smaller injectors).

Take the ECU, throttle body, distributor, O2 sensor, and anything else you can grab from it.

Go to this site and order a harness: https://warrperformance.com/throttle-body-injection/

Last thing you'll need is an adjustable fuel pressure regulator. A wideband A/F gauge wouldn't hurt either. This will help you adjust fueling since the 366 will not have the same fueling requirements as the 350/5.7 donor truck.

I did this exact swap on my Jeep which was a 1 ton rock crawler with a motor swap. It ran well with very little headache getting it set up. MY main reasoning was the carb bowls were getting starved during hill climbs and off camber situations and I didnt feel like dumping the money into an LS swap at the time.

[Booyah45828]

I've never converted anything as of yet, too many carbs in the attic to use.

But if I were buying a carb, I'd seriously look at the fitech units. They seem to be pretty robust and reliable units and are easily dialed in by the average joe. Plus, they can handle timing control too, which eliminates all the fuss with adjusting curves at/in the distributor.

The only thing concerning that I've read with the fitech units is fuel supply. The unit requires 50 or so psi to run, so you're essentially stuck with dropping the tank and installing an in-tank pump or using their fuel module that you can install underhood. I've read people have issues with their module "cooking" the fuel and causing all sorts of issues because of it. Some guys have turned their module into a bypass type setup so that cool fuel circulates through it. But if you're going to go through all that, why not just drop the tank and put the pump in there.

In your scenario with the 366, it's hard to say what I'd do. I'd love to try one of the standalone efi units, but I would more then likely stick with what I know and rebuild the current carb and run that. My thoughts is that if I was driving the bus enough to warrant spending 1k+ bucks on efi, I'd likely swap in a better engine that already had efi equipped. For the little bit that I drive mine, a carb would do just fine.

[NateS]

I know the OP has decided to go with a carb rebuild, but I thought I might share an ongoing project that is pertinent to the original inquiry.

I'm converting the Dodge 440 in my Superior Motorhome from an Edelbrock carburetor to a GM style TBI run by Speeduino.

Currently I'm finishing up the harness, I'm utilizing a Holley throttlebody with Delphi injectors and a spreadbore adapter off a 454. From my research, I found that the 454 adapters are the best flowing and have provisions for a coolant circuit so I can integrate a temperature sensor into the assembly making the install a little simpler.

Here are some pictures of the main assembly and the separate bits, the only other components beyond this are the ecu to tb harness, o2 sensor and high pressure fuel pump. I consider this a very simple and easy project for someone that is mildly handy.

[Jolly Roger bus 223]

Originally Posted by NateS

I know the OP has decided to go with a carb rebuild, but I thought I might share an ongoing project that is pertinent to the original inquiry.

I'm converting the Dodge 440 in my Superior Motorhome from an Edelbrock carburetor to a GM style TBI run by Speeduino.

Currently I'm finishing up the harness, I'm utilizing a Holley throttlebody with Delphi injectors and a spreadbore adapter off a 454. From my research, I found that the 454 adapters are the best flowing and have provisions for a coolant circuit so I can integrate a temperature sensor into the assembly making the install a little simpler.

Here are some pictures of the main assembly and the separate bits, the only other components beyond this are the ecu to tb harness, o2 sensor and high pressure fuel pump. I consider this a very simple and easy project for someone that is mildly handy.

use a die grinder and grind the edges off. just like porting heads?

[BeNimble]

Great keep up informed on how it goes. Like I said, I have a few Speeduino boards, and while I did not get to use it on my MX-3 racecar, I plan to use them for my other projects.

[NateS]

Originally Posted by BeNimble

Great keep up informed on how it goes. Like I said, I have a few Speeduino boards, and while I did not get to use it on my MX-3 racecar, I plan to use them for my other projects.

I will try and remember to pop in with an update.

I don't think Speeduino is right for everything but for this application it's pretty much perfect. I should only be in a few hundred bucks and have a setup that is easy to tune on the fly and uses inexpensive off the shelf components.

I love the mx3 with the v6, I had a Probe(mx6 chassis) and a Miata, the mx3 seemed like the middle ground between the two.

Cheers.

[vintageracer]

With the availability, reliability, ease of installation and better fuel economy offered by FI I can't believe everyone is not switching.

The Holley Snyper system is a great self learning FI system that you can bolt on in a weekend and never look back. $1,000-$1200 if you shop.

Expensive?

NO not at all and NO CARB to fool with. Great driveability in all weather conditions and elevations.

After FI it's time for an overdrive transmission!

[cadillackid]

I didn’t read in depth but yes TBI was offered on the 366 and it works well. 1990 was the first year of it I believe and it had an electronic timing ignition distributor and knock sensors. TBI is easy and auto adjust for elevation which carbs do not.

There’s lots on the old interwebs about tuning TBI, I still prob have the laptop software I wrote and the 160 baud ALDL interface. And I know I still have the EPROM burner and a bunch of hex tables for adjusting the fuel and timing curves when I used TBI on “built “ engines.. good times I had back then ! That’s how I got started in the car electronics world was E4ME electronic carbs and TBI.

[74gaschevcarpenter]

Chev tbi I backhoe. That’s pretty dope.

[74gaschevcarpenter]

I also have a 366 in my bus. Interested in swapping mine too. Just do it. Don’t let anybody tell you no. I don’t think it requires a cam or crank sensor just uses the dizzy to trigger it. Should be pretty simple just need the harness and all the sensors. I feel like it should bolt up to your carb manifold but if not aren’t big and small block intake manifolds the same? The trick would be that square drive distributor. I took the square oil pump drive gear off of the bottom of my points distributor and put it onto an HEI distributor without too much trouble.

[74gaschevcarpenter]

Lol you said electronic carbs. Good job. That stuff is complex as a mofo with proprietary problems for each individual application. Reverse engineering required for sure. Should have you come take a look at my 1983 tbi fuel injected Mitsubishi Starion. Not sure what’s going on with that ecu these days.

Edit: after looking up what e4me is I’m thinking it probably works better and is less complicated than I thought.

Originally Posted by cadillackid

I didn’t read in depth but yes TBI was offered on the 366 and it works well. 1990 was the first year of it I believe and it had an electronic timing ignition distributor and knock sensors. TBI is easy and auto adjust for elevation which carbs do not.

There’s lots on the old interwebs about tuning TBI, I still prob have the laptop software I wrote and the 160 baud ALDL interface. And I know I still have the EPROM burner and a bunch of hex tables for adjusting the fuel and timing curves when I used TBI on “built “ engines.. good times I had back then ! That’s how I got started in the car electronics world was E4ME electronic carbs and TBI.

[Jolly Roger bus 223]

FITECH is a cheaper version and supposed to be self learning.
i looked at it awhile back for one of my old trucks but it wouldnt work because i had already built true dual exhaust and it only supported one O2 sensor which meant i needed an H or Y pipe to read both sides collected before i went out dual exhaust.
thats the mess i cut out and didnt want but that was on my 77 ford 460 that had no electronics and i was already hesitant about adding the complication of electronics so i just went with a hi rise intake and a classic holley 850 carb.

[Blklstd]

Putting tbi on your engine is easy. GM sold many of them with it. Not sure ,but think they quit using them in 09. C6500 , Kodiak , and topkick had 366 tbi.