Soon to be msd atomic install on my 72 blazer

[72gmguy]

Last year I purchased an msd atomic fuel injection basic kit to install on a truck that I have since sold. I have decided to install it on my 72 blazer and have a couple of questions. I’ve already decided on ptfe fuel line after reading about all the issues with fuel smell and rubber based hose. Now I’m trying to find the best high pressure fuel pump to use. I looked on summit and every inline pump has complaints of quitting after very short run time. Has anyone had a good, reliable fuel pump they would recommend? I would like to use my stock tank but am open to other options if none of these pumps are reliable. How about the retro-fit fuel pump modules from Holley?

[Thealien]

In tank pumps are cooled by being immersed in the fuel. One of the reasons the external pumps fail. I don't have an answer for you but IMHO I would look for an in tank option!

[72gmguy]

I agree. I figured a lot of failures came from mounting the pumps too high or too far from the tank causing them to overheat. I was hoping someone here used one of the Holley retro-fit fuel modules for in tank mounting.

[mister.freeze]

I had Holley Pro-Jection for years. The pump in the kit never failed. Only removed and sold the system because I wanted more than the 650CFM it was rated. inline pump was mounted inside the frame rail about 2 feet from the tank.

[litebulblsc]

I have 2 vehicles running inline pumps. Neither gets driven much though...
Blazer has a cheaper Holley pump that came with the Sniper throttle body injection kit.
Then a Sierra I built with a dual Holley pumps with intentions of staging them, but have them wired together now.

Blazer's is mounted kind of high right above the axle in the frame rail. They tell you to mount them at the level of the bottom of the tank.

Sierra has them mounted below the fuel cell and cell is sumped

[72gmguy]

Thinking about trying this:
https://documents.holley.com/199r10934.pdf

I have an old poly tank that I don’t mind drilling a hole in to try it. It’s never had gas in it.

[72gmguy]

Originally Posted by mister.freeze

I had Holley Pro-Jection for years. The pump in the kit never failed. Only removed and sold the system because I wanted more than the 650CFM it was rated. inline pump was mounted inside the frame rail about 2 feet from the tank.

So the Holley pump worked for you. That’s good to hear. The reason I didn’t buy the master kit from msd was because of all the failures I read about with their pump. That and I wanted ptfe line. The In-Tank module ends up being $300 more than a medium priced Holley pump. Decisions decisions.

[72gmguy]

Originally Posted by litebulblsc

I have 2 vehicles running inline pumps. Neither gets driven much though...
Blazer has a cheaper Holley pump that came with the Sniper throttle body injection kit.
Then a Sierra I built with a dual Holley pumps with intentions of staging them, but have them wired together now.

Blazer's is mounted kind of high right above the axle in the frame rail. They tell you to mount them at the level of the bottom of the tank.

Sierra has them mounted below the fuel cell and cell is sumped

Thanks for your input. That’s two good Holley pump experiences. Starting to think that a Holley pump retro module may be the way to go. I see your in MI. I plan to be there for Woodward Dream Cruise in august....if the corona virus allows it.

[72gmguy]

I ordered the Holley retrofit in tank pump module from summit. I will have it Saturday. I’m going to get started on the install while I wait on the pump.

[72gmguy]

Started working on the blazer yesterday. Removed the carb and installed the carb spacer/adapter and the throttle body.

[72gmguy]

Drilled the hole for the Holley fuel pump module and cleaned up the tank.


Dropped the old tank and found every fuel line is hard and dry except for the fill which was soft and sticky like it was being eaten through. So I ordered some 1-3/8 fill hose to make a new one and I will use some standard fuel line to fix the rest.

Today I will try to make some lines to go from the pump to the throttle body with the ptfe line and -an fittings as well as install the fuel pump module.

[litebulblsc]

You might have a clearance issue with where you drilled your hole. If you reference my pic up above, it looks to be inline with the second to last body mount location. My tank pretty much touches that bed sill/ floor crossmember.

[72gmguy]

I thought that too but the kit comes with strips to lower the tank to use in place of anti squeak stuff between the tank and frame. They are about 3/4 inch so I hope I have enough room. The mat on the bottom of the tank is huge and makes mounting positions very limited.

[72gmguy]

You have to avoid the sender too.