Holley Sniper EFI install

[LB LandCruiser]

Last night I finally got the SBC fired up in my 73 FJ40. It has been down for a few days as I've been working on the Sniper install. The FJ had been my daily driver for several months and I was averaging 10.2 MPG.

I installed the Sniper setup on another classic car I have and was so impressed with the improved driveability I wanted to do the same to the 40. I am waiting on a heater shut-off valve before I put coolant back in the engine. The valve will be here in a day or two. Last night was a test fire to set the timing again and check for leaks. The 40 fired up and idled down perfectly.

I miss driving the 40. It irritates every Prius and Tesla owner I pass on the freeway.

 

[gwalt584]

This is awesome!

 

[WB8LBZ]

I have been thinking of this route for my 40, the Holly is getting long in the tooth. Any pictures?

Larry in El Paso

 

[LB LandCruiser]

 

[LB LandCruiser]

Got it out on the road today. Amazing. Throttle response is great, acceleration is faster, idles better, starts up easy. What's not to like? I did lose the temp gauge in the instrument cluster, though. The LCD monitor is mounted inside and it has a temp reading so it' all good.

 

[74fj40]

Are you planning to set up timing control?

 

[awynne56]

@LB LandCruiser did you do the easy set up I think they say just the 4 wire setup as they call it, how was the o2 sensor install, did you use the inline fuel pump? I'm really thinking about doing this but there are horror stories on Holley's forum about getting these installed and running right. you running a TV cable or Kickdown for you your trans. thanks for the info and help. glad you posted
Andy

 

[awynne56]

more pics

 

[LB LandCruiser]

The install is easy. Most of my time was spent planning wire routing and finding a switched 12V source that is on when the key is in the "run" position as well as the "start" position. Sometime in my 40's past, the wiring but buggered up so there was some troubleshooting unique to my ride.

Literally, a battery 12V lead, a battery ground lead, a coil wire, a switched 12V source (see above), and the O2 sensor.
You have to drain the coolant to replace the temp sensor and plug in the Holley harness. Easy.
I used the throttle cable that was already on my rig when I bought it. I purchased a cable end adapter (ball stud).
I bought weld in O2 bungs since the clamp setup included in the kit was not small enough to work on my exhaust.

I am running a single point distributor. Works great. No reason to replace a good dizzy just to have timing control. Not for the cost, anyway. I imagine running a dizzy with timing control would make it idle even better (like the LS in my wife's car), but it is a night and day difference with just the EFI.

I bought the master kit and used the inline pump. It is a little noisy in the cab when the system primes but it is only for a couple of seconds. After that, the engine fires and I can't hear anything anyway.

My transmission is a 3 speed manual, so I do not have a TV cable.

As for Holley horror stories, you can find bad info on everything. Just ask google and the internet will give it to you. This is my second Sniper EFI. There are known issues with the system such as the "high idle" but it is an easy fix. I had minor tuning issues with the first system I bought (it's on a 64 Cutlass, 330 CI V8) and had to fix the "high idle" on that one. This second system had updated firmware (maybe?) and I did zero tuning mods to get the thing running. I bought both kits from the same vendor. Chris has great customer service and tech support.

For $1300 to your door (signature required when ordering from Chris) it is hard to beat. With additional wiring (plugging in another supplied harness) you can control 2 electric fans and other stuff.

FWIW, I am building another Olds and will put the same system on it.

Grady

 

[LB LandCruiser]

 

[LB LandCruiser]

 

[awynne56]

Great write and pic @LB LandCruiser . The info was perfect def going to go with this. Thanks again.

Andy

 

[LB LandCruiser]

Another thing to mention regarding the wiring: an electric fuel pump has to be wired. The Master kit comes with the pump. The harness that comes with the EFI kit is very complete. It has the 12V lead for the pump but you have to make the ground lead. The relays and fuses are also built into the wiring from Holley.

Grady

 

[cult45]

What sort of mileage now @LB LandCruiser?

 

[LB LandCruiser]

Don't know about mileage yet. I will post the results when I fill up and run the tank down again.

grady

 

[Pierps]

Thanks for the write up! I really want one of these for my SBC.

 

[LB LandCruiser]

So, the issue I have had lately is a stall on deceleration when coming to a stop. It turns out that this is a common problem with the Sniper EFI install on vehicles with a manual transmission. Essentially, when I push the clutch in and ease on the brakes to coast up to a stop light, the AFR goes lean (18:1 or so) and the engine stalls. One workaround was to leave it in gear and slow to a stop and push the clutch as RPMs drop to near idle or a little less. It seemed the issue was engine load related and how the EFI adjusted the AFR when the engine load was suddenly reduced. I did not have this problem with the same kit install on my 64 Cutlass with an auto trans.

The EFI continued to learn and added fuel to the base map as it tried to correct the problem. I emailed Chris at EFISystemPro, who I bought the kit from, and included my config file and datalog for him to look at. He modified the base fuel table and emailed the file back. Because he knows what he is doing and I don't, I left it to him to see if he could figure out the problem based on the config file and datalog. I then dug into the files and looked for the difference. I learned a lot playing with the files on a computer and manipulating fuel graphs, etc. I still have not installed Chris's modified file.

What I did do was this: I disconnected my PCV valve from the back of the throttle body. The instructions say the power brake booster vacuum line goes there. I believe one part of the issue is the PB booster has a finite amount of vacuum that can be pulled while the PCV is a constant, erratic vacuum leak to the EFI. There is an idle air control valve (IAC) that adjusts air flow beyond what the butterflies do, that contribute to AFR based on throttle position (TPS). The numeric IAC value was out of whack (anywhere from 0 to 30%). One post on a Holley forum recommended the IAC value to be 10-20% for a manual transmission.

I also reset my timing and checked it two or three times after revving the engine. Once I knew timing was where I wanted it (12* BTDC) I tuned the idle, TPS, and IAC for about an hour to get the right values. All that was involved was tuning the idle until the IAC was somewhere around 10%, turning the truck off to reset the TPS back to zero (it resets when powered off) and starting the truck again to watch the idle RPM (850- ish), IAC % (near 10%), and the TPS ( 0%= zero throttle input). All done. I drove this morning to the gas station, filled up the tank, and had zero problems. I ran the truck to all 3 forward gears, hitting 5K on the tach in first and second, trying to create an issue. Had none. I will run errands in my 40 this weekend and see what else happens.

Happy wrenching....

Grady

 

[mcewan13]

@LB LandCruiser - Hey Grady, any news to share in dialing in the Sniper? I'm interested in putting one in my '73 3-spd F. Any additional tips on the install?

 

[badsamaritan]

Thanks for the info. I went with a Terminator kit for my BBC Chevelle and have been ok with it. It runs great when warmed up all the way, but the cold starts could use some work. I was thinking of going sniper on my 73 as I think the simplicity of it is awesome.

 

[tdskip]

Bump for how it all turned out (please) and any other lessons learned.