EFI

[TimBarb]

OK- decided to spend a little more money and go with an EFI on the new engine. 81 formula with 4 speed. I’m replacing the 305 Chevy engine with a 350. The 350 is a stock 4 bolt main with vortec heads and a mild cam upgrade. Looking for recommendations regarding an EFI . Thanks!

[ryeguy2006a]

Not sure what your budget is, but I'm a big fan of the Terminator X ECU that I'm running now. Depending on what you are looking to run, they have a line of Terminator X Stealth that are a carb replacement. They are $2k, so a little steeper than the sniper but well worth it in my opinion.

Another option that would probably be about the same price would be to use an EFI connection 24x conversion kit to give your SBC cam and crank sensors so that you can get a Terminator X ECU for an LS1. You could essentially fool the ECU to think that it's an LS1, while also upgrading to coil near plugs and get rid of the distributor all together. You'd need to get an LT1/LT4 intake, fuel rails and injectors too. Usually those can be found really cheap as take offs.

Keep in mind that any aftermarket ECU will require you to play around with the idle tuning as well as a bunch of other small settings. It will "self-tune" your fuel tables, but the data is only as good as what you put in. For example the Air-Fuel Ratio table is a user input and that controls how the fueling tables are populated. So if you have the AFR table too lean or too rich it will self tune based off of those values. Unless you are comfortable doing that on your own, I'd still work a tuning session into your budget. I have a buddy who is a wiz when it comes to the Holley software and can do remote tuning sessions live.

An example of the settings that you may have to play with is the IAC hold setting. IAC is a valve that controls your idle to add or subtract airflow to keep your target idle speed. Once you give throttle input the IAC goes to a "Hold" setting. If that setting is too high, your motor will take a long time idle down from any RPM. Too low and the rpm would come down too fast and the IAC won't be able to catch the idle causing the motor to stall.

Good luck and let us know what you decide!

Cheers,
Ryan

[scarebird]

I would not mess with a SBC; putting a LS3 was the best decision concerning my TA.  A take-out 5.3 run 2-3K and already comes with FI.

[FormTA]

I was going to say the same thing.  Go LS. I did my swap for basically free as I bought a really nice running 1998 Trans am and parted it out for more than I paid for the car which gave me money the fuel tank, pump and other odds and ends I needed to complete the swap.

Now my swap was the best case scenario as I found a near mint car for $5500 but, I would probably do it again as it gave me everything and more (like the rear brakes). There was also a Pontiac swap meet that I sold all the parts at in one weekend.

[TimBarb]

Wow- great info. The thing is, is that I have a fresh 350 on the engine stand and all of the accessories and small block parts needed for a simple engine exchange. I agree with all that an LS swap is really the way to go, and plan on that for a future project. So I’ll be using the small block I have on this one. That being said, what do you all recommend for aftermarket EFI with a budget of $1500- $1600 ? Again, thank you all for your input.

[737driver]

I’ve used the Holley Sniper and the MSD atomic Efi. I used the sniper on four builds and I really like it. For a Chevy 350 it will be a pretty straightforward install and will work really well. The Atomic installs similar to the Sniper, however the sniper does offer more advanced options. Holley gives pretty decent customer service as well.
The Sniper is a great unit and performs great.
Jim

[ryeguy2006a]

If you plan on going LS in the future, a good plan would be to go with the Terminator X ECU now, so that in the future all you need to do is swap harnesses. With the Sniper you cannot control an LS since the ECU is integrated into the throttle body. Although you could sell if/when you decide to go LS.

I'll be honest though, with a budget of $1500 you may want to either consider saving up a little more or sticking with a carb for the time being. In addition to the aftermarket ECU, you'll want to get a quality EFI fuel setup for your car. You could get away with running an external pump, but you'll still need a regulator with return line. The fittings, pump and regulator all add up pretty quickly.

If your ultimate goal is to have an LS powering your Formula I would be very strategic about what you purchase and make sure that it is compatible with an LS motor. For example when you upgrade the fuel system, make sure that you either set it up so you can turn up the pressure to 58 PSI where the LS motors usually run. When I had my Trans Am what I did was modified my fuel tank to run a 4th Gen fbody fuel pump assembly with a ring from Vetteworks. That worked really nicely and used OEM fuel parts, which I'm a big fan of. You could either run the C5 Corvette filter/reg to control the fuel pressure or an adjustable regulator.

I believe that Holley also sells a slim fuel pump that will slip into a stock tank without modification and will run at 58psi. Although I think that is a pricey option from what I remember. But the trade-off is the simplicity.

[TimBarb]

Thanks again for your response guys. Rye guy- I will most likely sell the formula after a couple years and build a TA. - I’ll be going LS and additional modern upgrades on that build. The formula will be mostly stock and just a fun cruiser. 737driver- thanks for your input. I’m seeing the Holley kit from summit and other suppliers for about $1500 including a fuel pump, fuel line, etc. Thank you all for your input. I’ll post with the final results.

[ryeguy2006a]

Sounds like a good plan if you don't plan to keep the car. Get it sorted for the next owner and then put the LS in the T/A. 

[Seven]

I went with the Holley Sniper Quadrajet on one of my projects so I could retain the stock spread bore intake manifold and maintain hood to air cleaner clearance.

[nUcLeArEnVoY]

IMO, throttle body EFIs are just glorified carburetors that work on positive pressure instead of negative pressure. I'd want an EFI system that is dry, and is as close to modern day fuel injection as possible and that would be the Edelbrock Pro-Flo 4. Pretty sure they make it for SBC, even for Pontiacs. You can also get it to work with a shaker hood and retain the original air cleaner. This guy did it on a '75: https://forums.edelbrock.com/forum/pro-flo-efi/pro-flo-2/2544-what-you-need-to-do-to-make-the-pro-flo-2-fuel-injection-fit-on-a-1977-trans-am

It is a multi-port fuel injection system that effectively replaces the entire intake with an Edelbrock unit built with ports for fuel rails and injectors. Also includes its own distributor so that the ECU can manage both fuel delivery and ignition timing for the best efficiency.

[scarebird]

I am running the Edelbrock setup on my 71 Lemans.  it is still in the operational learning mode.  A bit more money but as NuclearEnvoy notes it tie in the dizzy too.

But as noted - I would sell the 350 and jump straight to the LS and save money and time in the long run.

[nUcLeArEnVoY]

I am running the Edelbrock setup on my 71 Lemans.  it is still in the operational learning mode.  A bit more money but as NuclearEnvoy notes it tie in the dizzy too.

But as noted - I would sell the 350 and jump straight to the LS and save money and time in the long run.

Hi Scarebird,

I want to get a Pontiac build from Butler a few years down the road and plan on using the Pro-Flo system. How has it worked out for you? Seems like the most modern-like one available which is why I want to use it. Cold startups good, idle and power curve consistent?

Oh, and not sure if the cat in your avatar is your's but very cute! Got a little black-furred girl of my own, and even though she's getting up there in age she is still a handful.

[scarebird]

That is Max (1990-2006) Burmese/ASH mix - smart, tough, dog-like affection.

Only issue I have is a medium acceleration stumble.  Waiting for the PCM to learn more till I start serious diagnostics.

That said, knowing what I know now I would have sold the 440 Pontiac carbed combo and gone straight to LS.  My 2016 GMC Sierra has a 390 horse 5.3 that gets 22mpg on the highway.  It drops cylinders as needed and is very smooth.

[ryeguy2006a]

I am running the Edelbrock setup on my 71 Lemans.  it is still in the operational learning mode.  A bit more money but as NuclearEnvoy notes it tie in the dizzy too.

But as noted - I would sell the 350 and jump straight to the LS and save money and time in the long run.

Hi Scarebird,

I want to get a Pontiac build from Butler a few years down the road and plan on using the Pro-Flo system. How has it worked out for you? Seems like the most modern-like one available which is why I want to use it. Cold startups good, idle and power curve consistent?

Oh, and not sure if the cat in your avatar is your's but very cute! Got a little black-furred girl of my own, and even though she's getting up there in age she is still a handful.

Not sure if you have seen it or not, but T/AKidd (Larry) who used to be a big presence on this site developed a kit that allows you to add a 24x crank and 1x cam sensor to any Pontiac motor. That means with his kit, you could either use an LS1 computer or upgrade to a Terminator X and run the Pontiac with all the EFI advantages that late model engines have. There are also companies out there that will sell a carb flange to LS throttlebody adapter. With that and a Multi-port intake you could be running a sequential port, Coil near plug, fully EFI Pontiac motor!

Now that my car is basically done, I've been tossing around the idea of picking up another project maybe next spring. I've been seriously considering a 77/78 Trans Am and if I go that route, I'll be keeping the Poncho and adding Larry's 24x kit. 

[SoupMan]

I'll vouch for the Sniper EFI. Was an easy 1 day installation and I'm no mechanic by any stretch of imagination. I've had mine for 3 years.

For a Pontiac setup you will be wanting to tune, the Terminator as mentioned in the first response is a better choice. The sniper EFI has tuning but it's not as convenient as the Terminator.

[silver78]

Thanks again for your response guys. Rye guy- I will most likely sell the formula after a couple years and build a TA. - I’ll be going LS and additional modern upgrades on that build. The formula will be mostly stock and just a fun cruiser. 737driver- thanks for your input. I’m seeing the Holley kit from summit and other suppliers for about $1500 including a fuel pump, fuel line, etc. Thank you all for your input. I’ll post with the final results.

If the plan is to sell you may want to reconsider the extra cost of EFI as apposed to keeping a carb on the Formula. You already have SBC parts to keep the budget in line. Complete the 305/350 motor swap get the Formula on the road and enjoy it sooner.  Could consider using the $1500 budget to buy parts and turn the Formula into a TA.  Just a thought.   

[nUcLeArEnVoY]

I am running the Edelbrock setup on my 71 Lemans.  it is still in the operational learning mode.  A bit more money but as NuclearEnvoy notes it tie in the dizzy too.

But as noted - I would sell the 350 and jump straight to the LS and save money and time in the long run.

Hi Scarebird,

I want to get a Pontiac build from Butler a few years down the road and plan on using the Pro-Flo system. How has it worked out for you? Seems like the most modern-like one available which is why I want to use it. Cold startups good, idle and power curve consistent?

Oh, and not sure if the cat in your avatar is your's but very cute! Got a little black-furred girl of my own, and even though she's getting up there in age she is still a handful.

Not sure if you have seen it or not, but T/AKidd (Larry) who used to be a big presence on this site developed a kit that allows you to add a 24x crank and 1x cam sensor to any Pontiac motor. That means with his kit, you could either use an LS1 computer or upgrade to a Terminator X and run the Pontiac with all the EFI advantages that late model engines have. There are also companies out there that will sell a carb flange to LS throttlebody adapter. With that and a Multi-port intake you could be running a sequential port, Coil near plug, fully EFI Pontiac motor!

Now that my car is basically done, I've been tossing around the idea of picking up another project maybe next spring. I've been seriously considering a 77/78 Trans Am and if I go that route, I'll be keeping the Poncho and adding Larry's 24x kit. 

Had no idea tech like that existed! Where can I find literature on his kit? And where can I find LS-throttle body adapters and Coil-Near-Plug conversions?

[TimBarb]

Thanks again for all the replies and great info. - Almost too much info 🙂 ! Still not sure on what I will do- but I’ll post the outcome as soon as I get the engine swapped out. Thanks again all!

[ryeguy2006a]

Had no idea tech like that existed! Where can I find literature on his kit? And where can I find LS-throttle body adapters and Coil-Near-Plug conversions?

https://store.custombuiltmotors.com/air-induction/cbm-motorsports-90mm---105mm-billet-ls-throttle-body-to-4150-intake-manifold-adapter.html

I sent Larry a message. Maybe he'll chime in here.

[olds403]

A sniper/terminator/fitech are not in the same ball park as an LS / dry intake conversion.  The later is fuel rails 8 injectors, coil on plug, crank triggering/dual sync using oem/haltech/aem ecus.  Very different.  To tune such full efi /coil on plug motors you are hours/days on a dyno and burning money like its on fire.  Sure proven combos...losd the tune via laptop and send it.  One offs....break out the checkbook.  I am two days on a dyno dual fuel tunes and not cheap.  Sensors all over the motor. 

[737driver]

In my opinion, if your looking for an easy install, reliable operation, easy user operation, the Sniper is the way to go. The biggest consideration is what are your goals and expectations. The sniper works great across the board. Nothing gets to complex, and works great with classic V8s.
Jim

[ryeguy2006a]

https://www.pro-touring.com/threads/27647-1978-Custom-G-Machine-Trans-Am-IT-S-FINALLY-DONE!!/page13

Here's a link to his build where he mentions the kits.

[olds403]

You dont need to fire off the crank as that is batch fired efi as you can feed in the cam sensor iinput to the ecu  Dual sync distributors will do it on haltech/aem ecu’s and are sequential efi.  That TA build was with a gm ecu420 which is mid 90’s or so.  Probably had a custom tune to remove all the non-needed sensors.  Still super cool Efi/coil on plug using a dry intake.  You can run a sniper using dual sync.  I know enough to be dangerous, but leave the tuning to the pros

[takid455]

Tim - Read you are looking into the EFI world with your TA.  Not being happy with off the shelf options at the time, I design this system that does more than just monitor fuel. I wanted a full engine management system. I wanted it all. Fuel, spark, fan, trans & AC control. Starting with the LS (0411) ECU from GM, I reverse engineered the factory triggers &  made the components to provide cam & crank signals to the ECU but from the Pontiac engine. ECU doesn't know what the engine is. Just reads the signals.  Due to production cost, I ran batches of each piece to keep cost lower.   Having had it on the road for some time, all I can say is a Pontiac engine knew it could run so good. I have been around a lot of Ponchos. Cost will be more than the Holley offerings, but it is a more complete system in terms of what it can do.  Install is fairly straightforward yet leaves you with options for component selection.  All sensors & coils are common over the counter parts that you can get most anywhere today and in the future.  See pictures & video link below. Contact info is in the video link. 

Link to video of the system in operation:
https://youtu.be/vhTHRymPSlM

Olds403 - There's no 90's ECU in the 78 build linked above. By 90's I reference the early LT1 w/ chip units.  It started with an older Projection which was changed out to the LS late 90/ early 2000's 0411 ECU. The P59 could have also been used. Car or truck, it doesn't matter.  You are correct in the Multiport/ CNP systems are not comparable to the TBI units. Both will work, the former will have more control in each cylinder.  I have built a 403 with an early 90's ecu w/ multiport injection. It works but prefer the LS ecus for ease of tuning.

[olds403]

Stunning build.  Lot a thought went into yours for sure.    Thanks for sharing.  I used an AEM508 ECU. 

[ryeguy2006a]

I'll be buying a kit from you Larry, if/when I buy another T/A. I think rather than an LS, I'd stick with a Poncho and your kit. Maybe even fabricate a custom intake and using an LS Throttlebody. What's awesome is that you could also buy Larry's kit and it would work perfectly with the Terminator X or X Max kit. Kudos again man.

[TimBarb]

I think we can all agree that TAKID is a genius! Your engineering is beyond my old school knowledge but is so cool. Per my previous posts, I’m keeping the build on the Formula mostly stock . I’m considering the Sniper versus a carb for more reliability and less maintenance. The use of a LS engine and / or use of a stock Pontiac power plant with your control system,will definitely be part of my next build. I am saving all the responses in this message! I hope to be in touch with you in the future for assistance on my next project. Thank you for your response and expertise! The guys in this group are AWESOME.

[jugalo]

Tim - Read you are looking into the EFI world with your TA.  Not being happy with off the shelf options at the time, I design this system that does more than just monitor fuel. I wanted a full engine management system. I wanted it all. Fuel, spark, fan, trans & AC control. Starting with the LS (0411) ECU from GM, I reverse engineered the factory triggers &  made the components to provide cam & crank signals to the ECU but from the Pontiac engine. ECU doesn't know what the engine is. Just reads the signals.  Due to production cost, I ran batches of each piece to keep cost lower.   Having had it on the road for some time, all I can say is a Pontiac engine knew it could run so good. I have been around a lot of Ponchos. Cost will be more than the Holley offerings, but it is a more complete system in terms of what it can do.  Install is fairly straightforward yet leaves you with options for component selection.  All sensors & coils are common over the counter parts that you can get most anywhere today and in the future.  See pictures & video link below. Contact info is in the video link. 

Link to video of the system in operation:
https://youtu.be/vhTHRymPSlM

Olds403 - There's no 90's ECU in the 78 build linked above. By 90's I reference the early LT1 w/ chip units.  It started with an older Projection which was changed out to the LS late 90/ early 2000's 0411 ECU. The P59 could have also been used. Car or truck, it doesn't matter.  You are correct in the Multiport/ CNP systems are not comparable to the TBI units. Both will work, the former will have more control in each cylinder.  I have built a 403 with an early 90's ecu w/ multiport injection. It works but prefer the LS ecus for ease of tuning.

Wow, wish I had seen this 10 months ago!  Perfect setup IMO. Nice Work.

[Hoodshaker]

Thanks again for your response guys. Rye guy- I will most likely sell the formula after a couple years and build a TA. - I’ll be going LS and additional modern upgrades on that build. The formula will be mostly stock and just a fun cruiser. 737driver- thanks for your input. I’m seeing the Holley kit from summit and other suppliers for about $1500 including a fuel pump, fuel line, etc. Thank you all for your input. I’ll post with the final results.

Keeping your budget in mind- Holley has a few refurbished Snipers in stock right now in either shiny or classic gold finish (wish that was available when I bought mine) for $799- https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/factory_refurbished_-_sniper_efi/parts/FR550-510
https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/factory_refurbished_-_sniper_efi/parts/FR550-516

I'd grab one of those and pair it with their drop in fuel pump which allows you to use your stock tank and lines and doesn't require an external return line (does it internally) for another $368

Under budget, easy installation, burn rubber.

These are the parts I have here waiting for me to install in my '71 LeMans GT-37, but leaky valve seals (mission creep, creep, creep), and a Pontiac aluminum head shortage have me considering going with a cammed 6.0/6.2 LS instead (non numbers matching car). That's another story though.

[TimBarb]

Thanks Hood Shaker! Checking these out today. - awesome.

[jonathonar89]

So many options on this subject.

Like Ryan mentioned, Holley is great.  If you plan on doing any sort of engine swap or modification, get a kit with a separated computer.

If you’re for sure staying with a carb style intake, the Sniper is not a bad option.  You will just be limited to that setup if you plan on switching in the future.

That TAKID455 setup is awesome.  I remember Dave from PTFB was talking about it a while back when I used to help at his shop.  That’s an awesome setup for true GM parts/reliability.  0411 computers are 20 years old now but they still can rival the best EFI systems, as far as options go.  The downside is that they are less user friendly. 

[tiggershark]

I did the Sniper unit and a new gas tank with pump inside. Love it.

[FormTA]

I too may be in the market for an EFI system.  My problem is my options are limited as this is for a 301... what is the consensus on TBI type units?

[Jeremy]

I've got a FITECH on mine controlling the distributor as well.  I was real pleased with it before I had to pull the motor to fix a flat cam lobe.  I was able to get 22+ mpg on the highway and it drove great.  It did take some time to learn all of the definitions and tuning parameters but it was pretty easy to learn.   The self learning did alright but going above and beyond it was able to do so much more.

I did have to modify the front sump system from the float system to a pass through and it has been trouble free since.  I do think all of the new sumps are pass through now with a return line.

[TimBarb]

More great info. Thanks Jeremy. Still working on getting the 350 installed in the formula. Hope to post results soon!