News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

Holly Sniper EFI on a '61 Deville?

Started by 61canadiandeville, October 12, 2020, 09:37:45 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

61canadiandeville

Before I go deeper down this rabbit hole, has anyone installed, or know someone who has installed, the Holley Sniper EFI system to their 390? https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_4bbl_tbi_kits/sniper_4bbl_tbi_master_kits_with_fuel_system/parts/550-516K

I've seen a lot of videos of it installed online on many different vehicles, but none on a 390.

The downsides - it's not original, it's a bit of an overhaul of the fuel system and it's a little on the expensive side vs replacing/rebuilding a Rochester Carb.

The upsides - better fuel economy (would essential pay for itself in fuel saved), easier cold starts, no hassle self tuning.

One question I do have is will it work with the points distributor and ignition system? I'm an Autobody Technician at a GM dealership, so installation shouldn't be an issue. I also have another 12 mechanics i work with I can ask if I run into troubles.

Any thoughts on this would be greatly appreciated


wheikkila

Good Morning
I have installed many of the Holly EFI systems over the years. Going all the way back to the Holley's first pro injection. I installed it on a 67 Camaro that I owned at the time. What an improvement over the carb. Over the years I have installed the units on mine and others car with the same results. Now I did convert the points over to electric. Of course we were not showing the cars. We were looking for good drivability. I hope this helps some.
Thanks Wayne     

61canadiandeville

Quote from: wheikkila on October 13, 2020, 07:53:07 AM
Good Morning
I have installed many of the Holly EFI systems over the years. Going all the way back to the Holley's first pro injection. I installed it on a 67 Camaro that I owned at the time. What an improvement over the carb. Over the years I have installed the units on mine and others car with the same results. Now I did convert the points over to electric. Of course we were not showing the cars. We were looking for good drivability. I hope this helps some.
Thanks Wayne     

Good morning and thanks for the reply, Wayne.

I’m having issues with the carb, which is why I am considering the switch. The carburetor is well before my time (I’m 33), and finding people that know how to repair them locally is difficult. I can send it away or even attempt to do it myself, or I can go this way and install EFI. I do like the fact that having the carb makes it original. I’m very torn lol.

TJ Hopland

If pays for itself in fuel savings is important to you I would give up now.  Unless you are putting say 50K on per year or gas goes up well over $5 per gallon its not going to happen anytime soon.   I have heard of people say that EFI helped their fuel economy but those were the 'hot rod' guys that were running so rich your eyes would water if you were behind them on the road.

Sniper should work fine with points and that would be how you want to start out.   I believe you can buy a spark control module for it that interfaces with electronic distributors but you don't want to introduce too many variables at one time so its best to leave the ignition alone and get the fuel part up and running.   Once that works you can figure out what and if you have any options to do the spark control on that engine. 

What sort of issues are you having now?   I really get nervous when someone is hoping to solve an issue with EFI.   Spend lots of time on the forums trying to help people only to find out they are having the same problem with the EFI that they had with the carb which is actually a mechanical issue with the engine.   

What are your plans for fuel supply?  63.671% of the problems and complaints you read about on the forums are related to the inline fuel pumps.   Noise, short life,  priming issues, issues below 1/2 a tank of gas.   You don't hear about any issues with the in tank ones but thats only great for the cars they make EFI conversion tanks for.    I have heard decent things about some of the retrofit kits they have now.   You basically drill a new hole in the existing tank for the new assembly that has some sort of a foam like baffle around it.   They do seem to work better in deeper tanks.  GM really seemed to like big flat tanks where I think the sloshing is more of an issue.

A not perfect but reasonable option in a case like yours and what I did is to use what is often called a swirl pot or surge tank.   They get their name from racing and were a diy thing racers did because under certain conditions they could not get fuel from the main tank so they had this little buffer up front.   Its a small canister that contains a regular in tank high pressure pump.   Its got 4 connections on it.   One is the outlet to the fuel rail.   The other 3 are just open into the canister.   The 3 are inlet from the mechanical fuel pump, return from the fuel rail,  and return back to the main tank. 

They are slightly quieter than the inlines because they are surrounded by some fuel and in a canister.   Also helps that they are near a running engine.   They run a little cooler than the inlines because they are in a constant flow of fuel.   They don't have priming issues because they are almost always fully submerged in fuel.  The fuel is supplied by the mechanical pump which has no problem pumping air if it has to so no problem if the pickup gets uncovered because it will easily re prime and you have the buffer of fuel to keep the engine running.  Any air delivered goes to the top of the canister and is pushed back to the main tank.

They are not perfect,  they are not as quiet or as cool as if there was an in tank and you can hear them.  You also want to mount them as far forward as you possible can to avoid any hot airflow from the radiator or you can still end up with vapor lock.  The internal pressure and volume isn't that great so you can still get the fuel to boil on a hot day.   You also want to avoid any of the versions that have a float in them and claim not to need a liquid fuel return line which I think now may just be Edelbrock.    I have the older version of this one.  https://www.robbmcperformance.com/products/powersurge.html

If you don't have a return line on the car already the easiest way to add one is in the filler neck.  I believe people even make clamp on fittings.   Same thing for the O2 sensor in the exhaust if you don't have a way to get one welded in.  Custom exhaust shops are used to it now so you should be able to have it done pretty quick and cheap.   They will likely also stock the plugs but if they don't its a spark plug thread so an old spark plug will work till you install your system or if you remove it.

Also consider the electrical load and condition of your electrical system.  These systems get their power direct from battery and only use the existing wires as sensors so you won't be increasing the load on the fuse box or anything like that but you will be drawing 5-10 amps constantly for the injectors and fuel pump and such.  Do you have that much headroom?   Lots of the Camaro type guys that started with a non ac car find out the hard way they didn't have any to spare and end up chasing issues.
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

George D. Mukalian CLC # 10047

I installed on my 1969 Deville & it works GREAT!!

George
George D. Mukalian
CLC #10047

TJ Hopland

George, do you have any details to share?    What did you do for fuel supply?  How many miles on er?   Enough to prove me wrong about paying for itself?   I would be happy to be corrected on that,  it would be a decent selling point especially for those that need to justify such projects with others in the family units. 

And not that it will help with a 61 since its a different trans and dizzy but what did you do for the transmission kickdown?   And since you have distributor options did you upgrade anything there and are now doing timing control too?   

The 61 could require some extra creativity for the TV rod to the transmission and maybe throttle linkage in general.  I assume a 61 uses rods?    Rods have less flexibility than cables (pun intended).
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

bctexas

Hmmm - will converting to FI pay for itself?  A little time with a spreadsheet and an rough estimate.  Assume:

Gas at $3.00 per gallon
Mileage improved from 12 to 15 (I think optimistic)
Cost of system $1900.00 - assumes DIY installation.  Basic Sniper Quadrajet system from Jegs, the RobbMc fuel system mentioned earlier, and $300 in misc expenses.

If you drive 12,000 miles/year, you pay back in just over 3 years.  But if you drive 3000 as a collector car, almost 13 years.  Lower the fuel mileage improvement to 14 mpg and the payback becomes 4.4 years and almost 18 years.  I don't think financial payback is a good argument for the conversion unless this is your daily driver going to work every day.  Which quite frankly doesn't sound like a really good idea to me either.  My commute of 21 miles each way involved lots of dancing with Suburbans and giant pickups driven by people putting on makeup, eating breakfast, talking on the phone and driving 75mph.  All at the same time.  I wanted a modern car with belts, airbags, disc brakes and crumple zones for that party.

All that said, I don't see the decision based on financial payback.  I think it would just be fun to do.  I have to admit, my '65 starts and runs pretty darn well on the Edelbrock that the car had on it when I bought it.  So I don't have a lot of incentive to mess with success.  The $ are going to fixing the AC and some other stuff before I think about FI.

Whatever you decide, I just hope you enjoy it.  That is what this is all about!
1965 CDV
1970 SDV

TJ Hopland

Yep if MPG is a factor for you do the math and make sure it works out the way you need it to.     
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

fishnjim

I think you should assess what the problem(s) causing your dissatisfaction is first (rough idle, cold starts, bogging, etc) and what the mileage and condition of the car is before you embark on a high tech upgrade when you might have problems below the intake, that the EFI can't solve.   Talk to some of those mechanics you know, they might help out.   Alot of wrench turning was done for a few chilly ones.
I don't take an opinion pro or con here, I know they both can be made to work just fine or they never would have sold a single '61 DV or EFI kit.   
Carbs are fairly straight forward but seem to intimidate people that are unfamiliar like most things.  There's a steep curve of changes to operation in those years.  '61 is still in the early 4 bbl era and they get ironed out by mid 60's.   We're spoiled these daze by a system that does everything for us, effortlessly, so we don't have to understand or know how.
Barring rebuild, another solution maybe to swop out the carb for an Edelbrock performer, or something similar, new in the box.($4-500 USD)   Rebuild yours yourself, and learn the "ropes" and it'll eventual start to gel.   There's plenty of race cars that rely and relied on carbs because they're quite versatile in terms of performance upgrade and inexpensive compared to the alternatives.   So I wouldn't fault the technology, but maybe find answers in the condition of the car.   
But you have to do what's right for you and what you're comfortable with, I can appreciate that as well.   I'm just challenging the big leap assumption and offering small step alternatives.   Solve the problem, don't make it more complex.   In order to do that, you have to identify what the problem is before you can solve it.  Then break it down in it's components and solve each one.
Risk: If EFI doesn't do as you think, then you'll be trapped by the investment changing more stuff and should've consider a rebuild or other solutions.   Sexy advertising is meant as a $$ trap.

bcroe

#9
Quote from: bctexas
Mileage improved from 12 to 15 (I think optimistic) and driving 75mph. 

A 25% improvement is extremely optimistic. A certain 4100 lb car here gets
19 mpg (calibrated speedo) at 70 mph under favorable condition with a carb,
does it with a very efficient transmission and a 2.41:1 axle ratio.  Bruce Roe

George D. Mukalian CLC # 10047

I replaced the 472 with a 1970 Eldorado 500. The whole motor was rebuilt and modified.
The motor was on the dyno: 565 HP 714 Lb/ft torque.
I replaced the fuel tank with an identical tank with a submerged fuel pump.
The Holley Sniper works fantastic!!! I definitely recommend it.

I've attached a picture of my car.

Actually, my mom bought the car in 1969 and gave it to me. I completely restored it to original except the motor.
I need a lot of horsepower!!!

George
George D. Mukalian
CLC #10047

TJ Hopland

Quote from: George D. Mukalian CLC # 10047 on October 19, 2020, 03:33:35 PMI replaced the fuel tank with an identical tank with a submerged fuel pump.

Tell us more about this tank.   Just a reproduction tank with one of those retrofit pump kits?    Or did you find someone that is building a baffled EFI tank to fit your car?
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

George D. Mukalian CLC # 10047

The tank was almost identical to the original in dimensions, with a few modifications to install it. If anyone is interested I could supply the company.

George
George D. Mukalian
CLC #10047

rajeevx7

The engine size is irrelevant. Your only concern is the FI bolting to your intake mani.
Upgrade the ign, install the FI and you won’t ever look back. The Sniper manual will tell you exactly what to do.
Fuel savings, miniscule.