Converting 1970 396 to Fuel Injection

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I am considering converting my 1970 Chevelle 396 to Fuel Injection. Sounds cheap up front but I am wondering how much the swap will cost me real time. Ideas and opinions appreciated as this is a numbers matching car.

Thanks!
 
Are you thinking of converting to port injection, or throttle body injection? The number of options out there are bewildering. What are your ground rules going in? Do you want to buy a self-contained throttle body unit that bolts to the stock intake manifold?
 
Several years ago I converted a 1981 Pontiac Turbo Trans Am to EFI. I used the MSD Atomic EFI system. Costs have come down, but I had probably $3k in the whole system including fuel tank, ignition, etc.
 
I have installed a few retrofit EFI setups ranging from TBI self learning plug and play to full sequential multi point conversions. For the look of OE, quality of aftermarket support, tuning capability, and expanded capability should you want it, look no further than the Holley Terminator Stealth. If you get one with transmission control and want to add a 4L80E down the road, you're covered. Want to have the ECU control timing, in addition to fuel, you can do that too. Fuel system, you can keep the stock tank and run an EFI surge tank, or convert to a drop in EFI tank.

I'm currently building a hydraulic roller square port 496 for a 68 Chevelle. Owner is going from a 396/TH400 to a 496 with Holley Terminator Stealth and a 4L80E, Holley will be controlling fuel, spark and transmission.
 
Originally Posted by bdcardinal
The Holley systems are the way to go now.


Agreed. I'll be using one on my parent's boat unless I can magically find a fully intact marine EEC-IV system in the interim.
 
Funny how this has come full circle. When FI started becoming popular in the 80's, everybody complained how mysterious and complicated it was and the average home mechanic won't be able to work on it. Now people are paying a premium to convert old cars to it. Why do you want to convert?
 
Originally Posted by Imp4
Originally Posted by Propflux01
If you can handle the price....

https://www.jegs.com/webapp/wcs/sto...toreId=10001&sType=&pgGrp=search

Geez, not for the faint of wallet. Nearly $4k......

I know nothing about these things.
Does something like this do a better job (performance, reliability, economy, etc) versus a more reasonably priced option?
$4k USD is the cost of an LS swap, those high dollar MPFI kits are the sort of things you saw in early 2000s car mags. Completely obsolete as anyone who needs MPFI will just swap in a motor that was designed for it these days.

That's $4k for a canned tune that you might not be able to change easily. You might as well just go with a custom tune on a truck TBI, which is closer to what the Holley systems are but self tuning.
 
Originally Posted by atikovi
Funny how this has come full circle. When FI started becoming popular in the 80's, everybody complained how mysterious and complicated it was and the average home mechanic won't be able to work on it. Now people are paying a premium to convert old cars to it. Why do you want to convert?
The mechanic's boogeyman changes every decade or so. New carb = 500-$700 USD, EFI system $1500 USD + fuel system upgrades. No one is going to be able to service Quadajets in a decade or so and they will only exist in museums.
 
I have 69 and 71 SS 396 camaros, both 4 speeds. They have the original quadrajets, with epoxied fuel bowls and bushed throttle shafts. Both have Crane 272 cams. They run fantastic, good economy and performance. I would never pay $$$ for the hassle of aftermarket FI with all sorts of sensors you can only get from them. They do have HEI distributors though.
 
The big block in the 77 stepside in my sig is on it`s 3rd carb and will get a well tuned quadrajet this spring. Thought I wanted injection but got over it after much research. The 800 cfm Edelbrock on it now is a smooth running dog.
 
For a numbers matching car you don't intend to take any further, Holley Sniper not a second thought. Much less wiring and you don't have to figure out where to put the ECU. You can do it in a long weekend. Only thing I would say is make sure you have room for a 1" open spacer.

The Terminator Stealth is also a nice system, it is a bit more complicated to install but has more capability. The O2 sensors are proprietary to Holley and there is one other on one system (it may be the TPS on the Sniper) but the rest of them are standard GM stuff that most any parts store will have, part numbers are readily available on the Holley Forum. The Holley Terminator (and Terminator Stealth) use HP or Dominator ECU depending on if you order the one with trans control or not... so skys the limit with them.

Either system can control timing using a small cap HEI (or Ford TFI) distributor.

If you're actually going to drive the car in various conditions... there is defiantly something to be said for walking out to your hot rod in 30 degree weather and have it fire off first try, settle in to a smooth idle and drive off with zero fuss...
 
Originally Posted by OVERKILL
Originally Posted by bdcardinal
The Holley systems are the way to go now.


Agreed. I'll be using one on my parent's boat unless I can magically find a fully intact marine EEC-IV system in the interim.

Ebay ? I have a full system from a 502 MPI in my garage- waiting on me to get around to rebuilding it.
 
EFI would be nice but I think I will stick with the Edelbrock quadrajet that is on the 396 in my 70 Monte Carlo. I've had this carb on this car for over 20 years and it still works great.
 
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