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Holley 550510 Electronic Fuel Injection

Holley 550510 Electronic Fuel Injection

Holley 550510 Electronic Fuel Injection
$ 1,070.95

Score By Feature

Based on 20 ratings
Delivery
7.12
Value for money
7.48
Packaging
7.47
Giftable
7.09

OveReview Final Score

How Our Score Is Calculated

Product Description

This dual pattern bolt on carburetor assembly replaces carburetors on 4150 Flange and Spread Bore manifolds - (To seal through the spread bore, there is part #9006).
There are no extra boxes to mount since the ECU is mounted directly to the throttle body. It supports 4 100 lb/hr injectors and can produce up to 650 horsepower!
There are only 4 wiring connections required! It will have to have only four batteries (Battery +, Battery -, Switched Ignition, and Installing a Flame Arrestor, such as part number 720-1 or 720-13, is REQUIRED for marine installations.
It doesn't matter whether you're an ECU wizard or not you can have EFI without being a computer savant. Easy Calibration Wizard (Ask a few questions about your engine, and the program creates a base map, then it starts tuning by itself! 2) - Laptop not needed! Refer to the PDF file attached below in the Technical Specification for User Manual for more details.

Questions & Answers

Can it be used with PCM? Do you think it is better to just run without the factory PCM?

There is everything necessary for starting in the throttle body, just a few wires to connect, and you are ready to go

The holley blue electric fuel pump is not included with this kit. Does this work with it?

For high pressure, you need high temperatures. A holley blue's pressure is 12 psi, while 58 psi is needed for a blue.

How will my kickdown work with an AOD? Is there an attachment to go along with it as well?

You will need a bracket for the throttle cable and a kickdown cable with the kit. That worked for a 700r4, but I had to use a transmission pressure gauge to verify that the line pressures were correct.

What are the fuel lines and fuel pump included in this unit?

Whether or not you need it will depend on which That wasn't the case with mine.

Selected User Reviews For Holley 550510 Electronic Fuel Injection

This issue has been resolved and I received the items I was searching for - thank you Holley! Broken again after that
3/5

I am giving it 3 stars since it is installed on my vehicle, but I am missing two important wiring harnesses that did not come in the box, so I can't launch my vehicle yet. This is the part that I am missing The part numbers 491 and 558 are output harnesses The 490 will come with the main harness and ignition adapter. It is impossible for me to test the new EFI, and I am not sure how they could miss two of the However, I am not able to test it without the straps so I am at a loss for what to do. It looks really cool sitting on my engine. There have been similar complaints about missing parts at Holley, so maybe someone there will read this. A. UPDATED The harnesses I needed were shipped to me no charge by Holley within two days. A brief update A few days after sending 28 emails back and forth with a tech to get them to open a ticket, the unit is back at Holley. He admitted that 10-hour shifts are not in the pipeline after chatting over the phone and email for two weeks The tuning of 20% of the sniper systems is not working properly. That could have been done without weeping and crying and admitting it upfront. Take that back to bench testing and fix it. I have had the car project done for over a month now after a year of rebuilding for an EFI system and other items, but I won't be able to drive it until Holley fixes the sniper unit and gets it I would recommend staying away from this and going with a ProM unit instead.

Eileen Bartlett
Eileen Bartlett
| Feb 16, 2021
It runs great and is no longer stinking of gas
4/5

Among the reasons I installed the Holley Sniper EFI and the Holley Sniper Fuel tank when I modified my 1971 440 Cuda was to eliminate the gas smell. Even though the car ran well and you and your house smelled like an old gas station after driving it, the carb was fine. As opposed to my expectations, she started right up and ran smoothly right out of the box after I followed the installation video exactly. It was great driving around to let it self-tune and I could not be happier with how the Sniper does. Cold starts and gas smell problems are no longer, and fuel mileage is better and horsepower is increased. There was only one tricky part finding a 12V connection during cranking and running. Due to the fact that old Mopars don't supply power from a single source, I had to come off two sources and run through I have only found one thing negative so far with the Sniper EFI system, which is my EFI monitor will switch to a different screen after driving for a while. I'm not sure if this is by design or whether my hardware has an issue. The only reason it didn't get 5 stars is because of this issue.

Liliana Moore
Liliana Moore
| Feb 06, 2021
I think this is an excellent product, though I'd check the parts box before ordering! The product appears to be very good
5/5

I have installed it on a 350 Chevy. It is easy to install and it can be self-installed A carburetor killer, it has a wide range of tuning possibilities. The main wiring harness did not come with both boxes in a row in which I bought this off Amazon. I received two, yes two, boxes in a row with this problem. The good news is that Holley got I asked them to night me the missing harness, but I can't guarantee that they will do so for all of them.

Crew SINCLAIR
Crew SINCLAIR
| Apr 06, 2021
I don't have any complaints about installing it
3/5

It was installed on my 1978 F150 equipped with a 400 horsepower engine. I don't have any complaints about installing it. 2 weeks after I installed the throttle position sensor, I went through a car wash and it destroyed it. The hood was not on at the time, so I do not know how that happened. There was a two-week backorder so the pickup sat for two weeks while the throttle position sensor was being ordered.

Elliot Quinn
Elliot Quinn
| Aug 13, 2020
Do yourself a favor and think twice
3/5

On this unit, I first noticed that the finish was not nice and shiny, but rather looked like someone had used spray paint to paint chrome onto plastic. There's nothing fancy about the finish (you might consider going for black if you decide to buy). The first time I installed it, I ran into A crossover hose was leaking fuel from the engine which caused the engine to run poorly. When I first contacted Holley, they wanted to charge me shipping to send it in to be repaired In the end, they decided to comp the shipping, and about two months later I got it back with a new fuel pressure regulator and a new crossover pipe. It didn't leak anymore, but I didn't even get the chance TPS was reading 100 after I hooked it all back up, and it refused to adjust. So after spending weeks at Holley getting the machine fixed and checked to make sure it was working, I got it back with a brand It is my pleasure to announce that Holley is sending me a new TPS (overnighted, which is nice of them). As a result, I am now able to use the system I bought almost two months ago after it fixed the problem. There is no question that all the talk about plug and play and ease of use is After a lot of money was spent on my carb and inherit problems, I managed to get them under control. As far as installation is concerned, it was relatively straightforward. However, now that it has been tested, it does run reasonably well. The harness and relays could have been much better-quality and more customizable, but that's just a minor gripe. A carburetor starts and runs much cleaner than one that is carbureted. While the carb is more erratic, the idle tends to be more erratic. There were some benefits to the product, but they did not outweigh the problems and cost. I suggest doing a lot of research and tempering your expectations before buying.

Briella BYRNE
Briella BYRNE
| Apr 24, 2021
Installation will be more costly due to the additional modifications required
5/5

Installing and wiring the device into a vehicle is a relatively simple task.

Lilyana Conner
Lilyana Conner
| Apr 06, 2021
Compared to the Edelbrock, a huge difference is seen at idle and in performance
5/5

Compared to the Edelbrock, a huge difference is seen at idle and in performance. It is fair to say that the Edelbrock engine came out of the box and was never tuned, aside from the idle speed and idle mixture. The Vortec 350 roller cam was installed on an 880 block with H10 cylinders. The number of comps. is 51. A Borla header or exhaust system, for example.

Gracelynn Raymond
Gracelynn Raymond
| Aug 07, 2020
This carb is for the sniper efi
5/5

Installs and tunes easily and is a great product.

Emory Ramsey
Emory Ramsey
| May 04, 2021

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