aftermarket EFI systems

MY85pontiac

im too old for this crap!
Joined
May 17, 2002
i dont knows if this belongs here or not but i have a n/a buick engine so i thought i'd post this here since it is a non SFI post.

for those who even care i have a 85 GP with a 3.8. its the original engine with 140,000+ miles on it and to be honest, even though its not powerful it still starts the first time every time and runs very well and i'm happy with it. however i HATE the carb on it. i change it with a remanned unit and while i'm not having any problems with it i just dont like 2 bbl carbs. now the car is 18 years old and carbs a re a bit outdated. now i like carbs, dont get me wrong but i dont want another carb on this car in the future. i plan on keeping this car for a long time to come and ive been kicking around this idea of retrofitting it with a EFI system later on. one system i'm look at is holley's 950 command EFI system. its a speed density based EFI system with a GM style 2 bbl style throttle body that is either 400 CFM or 670 CFM and then they have 4 bbl versions that are 650, 750 and 900 CFM. it is very tunable from what i understand (requires a laptop for the software it comes with) and it can even control your ignition or use a vacuum advance distributor if you want. it has a O2 sensor, water temp sensor, air temp sensor and a map sensor.
the 650 CFM 4 bbl version is for 150-275 HP engines. it can be used on 4 cylinder, 6 cylinder even fire (said even fire specifically so i guess odd fire engines are out) and V8 engines. so this system seems very flexible to me. this is NOT like their projection 2D system where its very limited in tunability. it comes with everything you need (aside from a return fuel line and stuff like that) you install their system. now if i went with the 2 bbl GM TBI style version i'd have to use their adapter plate to a rochester 2 bbl intake or i can use an after market intake and go for the 650 CFM 4 bbl version and dump the EGR and other emissions crap i wont need later (i think i want to do this when its old enough for antique tags to avoid the smog police). of course i can use the 4 bbl 4.1 intake i have but like i said i want to ditch the emissions crap when its old enough for antique tags. either i'll get this engine rebuilt or just get another rebuilt engine and keep this one and get it rebuilt for later use as a spare. about the only thing i'd do is add an aftermarket cam and headers to the engine to up the power. an aftermarket intake would give me more gains than either factory intake so i'm kinda leaning towards the 4 bbl version. i know if i set the engine up right 650 CFM wouldnt be too much for it to handle. supposedly the system is suppose to help smooth out idle, improve drivability, etc. and those are other reasons why i'm looking into it. i know TBI is just a step up from a carb and is like "primitive EFI" in a way but i want something better than a dualjet and i want more tunability. as it is now there isnt much to tune on these carbs. with the 950 command system you can tune fuel and spark maps. the system cost 1300 bucks, which is par for the course when it comes to a "complete" EFI system. the only two drawbacks to me are the price and it requires a laptop for fine tuning. since my application would be "custom" i'd have to have to have a laptop. they have downloadable "base maps" but they're all for V8 engines. i've looked at other systems but i think this one is the best choice for me so far.


i'm looking for anyone with any experience with this system and i'm looking for general opinions, if anyone thinks i'm nuts or stupid or whatever. i want something "different" and sticking with a 3.8 instead of putting in a SBC is a good start to being different. ive also never heard of anyone using an aftermarket EFI kit on an n/a 3.8 before either. i dont want to go "all out" on the engine later but i do plan on bumping up the power to about 150-250 HP. it'll probably always be a daily driver so it doesnt have to be all that powerful.

so if you were to chose an EFI system for your engine what would you chose and why?
 
what? no opinions? wrong forum? whats the deal? i know some of your read this so why no reply?
 
You are in the right section...It's cause taking me longer to answer this. I know that (thinking Accel) started making a EFI system back in the late 80's. I have the mag around somewhere and am trying to find it.

At a min I would say swap for the 4.1 intake & Q-jet ( I know you want to dump the carb) but at want cost verses gains???

Not wanting to go all out is cool here, just trying to imporve want you have. :D

Check out Rich's site for some good info.
http://www.flash.net/~rjgeorge/NAnotes.htm

HTH
Jim
When I find the other EFI system I'll let you know
 
Right place. Just that long questions need long answers and long answer take time. ;) I'll give you my opinion (I thought about this a lot before), but let me first ask two questions:

How much money and time to convert (ballpark)?
What are the primary advantages (other than getting rid of the carb)?
 
How much money and time to convert (ballpark)?

since it wont be for awhile time is not an issue and probably never will be and as for money i dont think that will matter either. i saw an auction on ebay for the very same system i'm looking at (650 CFM 4 bbl TBI, BRAND NEW) with a starting bid of 647 bucks(normally its 1300 bucks). so i might be able to find it cheap in the future.

What are the primary advantages (other than getting rid of the carb)?

the most obvious advantage is YOU can control the fuel and spark curves. the computer will just do what you tell it to. this is a decisive advantage over a CCC carb set up. the CCC carb set up does what its programmed to by GM, and those settings are generally for emissions and fuel economy. whats the most you can do with the stock computer? put in another chip? not very flexible IMO. other advantages would be smoother idle, more precise fuel metering through out the RPM range (which can sorta be construed as better fuel economy but this largely depends on other factors like cam, gearing, etc), tunability, can be used with turbos or superchargers (just needs a 3 bar map sensor), improved drivability. and lets be honest we know these carbs are not very precise no matter how much you tune them (refering to dualjets here). it can also be used on all kinds of engines (so if i go to a V8 i can still use this system). i can keep the distributor i have now and i can control the spark or i can use a vacuum advance distributor later if i want. the system is that flexible. it can also control electric fan operation, a/c, etc.

aside from plumbing a return fuel line they provide all you need to set it up (even sensors, O2, water temp, MAP sensor), they even detail what tools you'll need and what other supplies you'll need to complete the installation. i'm sure this is just a general guideline and probably wont apply to every application but it looks like they put a lot of work into this sytem. and you will need a laptop to program it, it comes with the software needed. if you have a SBC, they have downloadable maps on their site you can use and tweek. basically it can be used on 4 6 or 8 cylinder engines. the connectors are GM style and so is the 2 bbl throttle body (400 and 670 CFM respectively).

i think for gaining control over spark and fuel delivery and being able to fine tune it myself i think it'd be worth the 1300 bucks.

it's not like SFI but its a step up from carbs. like i said, i like carbs but not on everything i own. i think its the CCC carb crap i hate more than anything.
 
Right after I bought my first Carb/Turbo, we got a '87 Monte Carlo LS with a 4.3 TBI V6 for my wife. Great motor, IMO, for "driving". Never had a problem, good power and very reliable. My carb was giving me fits and I told myslef I would never have another carb again. :eek:


The Holley you're describing seems more reasonable dollarwise than when I last checked on aftermarket EFI. They were all ~$2000. I figured for that money it would be better to adapt a GM factory EFI system. When I looked at what was invloved with that, there were two opitions, TBI or port EFI. The port made more sense, because it's already available for the Buick V6. Adopting a 85ish FWD EFI to RWD shouldn't be too tough. BUT at that point, might as well add the turbocharger, because it's easy next to the work involved for the electrical and fuel stuff. So for each step, just a little more got you a lot farther until your all the way to a 86/87 SFI/IC/Turbo Bucik V6. And the general opinion is it better to just buy a 86/87 TR than make (convert) to one, so you're suddenly back to square one. :rolleyes:

Then the more I learned about how well these cars run with a good carb/sensors/vacuum lines, the less attractive EFI became. I find that even with CCC, I have a fair amount of control over the timing (adjust initial, boost retard with MSD box) and fuel (Q-jet secondaries aren't CCC controlled) so again, less need for EFI.

You can get a 4.1 intake and q-get for ~$75. That will get you some control over the fueling. Most igintion boxes will give you some sort of control over timing for a reasonable price. Both will give you a bump is power.



So the Holley at that price seems like a better deal, but personally the money and time would seem better spent in other ways for me. With EFI, you get a little more control and little more tuneability, but is it worth it? Well, maybe. :)


HTH
 
Right after I bought my first Carb/Turbo, we got a '87 Monte Carlo LS with a 4.3 TBI V6 for my wife. Great motor, IMO, for "driving". Never had a problem, good power and very reliable. My carb was giving me fits and I told myslef I would never have another carb again.

my first car a 86 parisienne with a 4.3 TBI. i loved that engine and i loved that TBI. i know its not as good as port injection but i still love TBI for what it offers. its almost the perfect medium between a carb and port injection. TBI can be tuned more precisely than a carb but is more forgiving than port injection in terms of tuning. i like GM's TBI BUT, like CCC, its not as tunable as an aftermarket system because its preprogrammed and you cant mess with it! (for obvious reasons)

The Holley you're describing seems more reasonable dollarwise than when I last checked on aftermarket EFI. They were all ~$2000. I figured for that money it would be better to adapt a GM factory EFI system.

usually with a factory TBI system its programmed for certain parameters in terms of engine size and cam specs, CR. it is also set up for emissions and fuel economy. with the holley system you can run just about any cam you want, any cubic inches you want, any CR you want. you just enter the values into the laptop and boom, its ready to run. while a junkyard TBI system out of a car might be cheaper you cant tune it like you can the holley set up. you can run that holley set up on just about any engine you want. and the holley kit is all new parts, not much to worry about in terms of something failing because of age or excessive use. that is another thing to consider.


When I looked at what was invloved with that, there were two opitions, TBI or port EFI. The port made more sense, because it's already available for the Buick V6. Adopting a 85ish FWD EFI to RWD shouldn't be too tough. BUT at that point, might as well add the turbocharger, because it's easy next to the work involved for the electrical and fuel stuff. So for each step, just a little more got you a lot farther until your all the way to a 86/87 SFI/IC/Turbo Bucik V6. And the general opinion is it better to just buy a 86/87 TR than make (convert) to one, so you're suddenly back to square one.

yes i know....its like "well hell, i might as well get a 86-87 GN engine if i'm gonna add EFI and stuff." but i may never add a turbo to this engine. maybe others but not this one. that being said it turns this into a whole new ballgame. since i'm not adding a turbo its a whole different animal.


Then the more I learned about how well these cars run with a good carb/sensors/vacuum lines, the less attractive EFI became. I find that even with CCC, I have a fair amount of control over the timing (adjust initial, boost retard with MSD box) and fuel (Q-jet secondaries aren't CCC controlled) so again, less need for EFI.

but for those secondaries you're changing hangers, you'r changing rods, your changing the cam under the hanger. you're having to test drive it each time you tweek it, etc. ONCE you get it just right its ok but all the work of taking it apart and getting it back together is a nuisance and this holley kit can eliminate alot of that bothersome work. there are no rods or hangers to change. no secondaries. it has progressive linkage and it control idle speeds on its own. of course some people are not thrilled about punching numbers into a laptop but i think it beats chasing my tail trying to tune a carb. and with a carb you're tuning it by feel. its a real rough way to tune an engine. who wants to listen for pinging and take it back home and richen it back up until it stop pinging? with the laptop you can do it right on the side of the road, real quick adjustment. i guess part of the reason why i'm leaning towards EFI is because i'm more familar with it than carbs. they both have their good and bad points and i want something more accurate. and it'll have less lines and crap once i remove the emissions crap later on so a couple qires and lines running to a couple sensors isnt going to bother me at all. it'll still be an improvement over what i have now, which you might as well call a rats nest.


You can get a 4.1 intake and q-get for ~$75. That will get you some control over the fueling.

i have the intake and i had the carb (till it had a meeting with a ten pound sledge hammer) off my 4.1 (the 4.1 is in my 82 GP LJ but i'm putting something else in there, maybe a pontiac 400, not sure. want the 4.1? come get it!). then i'd have to get different secondary rods and go through the rather annoying task of "tuning" it right and to be honest i am really not wanting to do that anymore. also i MIGHT go with their 650 CFM 4 bbl kit and i'll probably wind up getting an aftermarket intake for improved breathing capability.

Most igintion boxes will give you some sort of control over timing for a reasonable price.

yeah i already plan on buying a MSD 6A (no need for the RPM limiter on a what is going to remain a daily driver car). i've already added an accel super coil and i'm using blue thunder wires and regular AC delco plugs (.060 gap). so far the ignition has improved and i cant really say i've noticed a difference but it sure has helped burn cleaner than it did before when it was stock so it must be doing something right.

So the Holley at that price seems like a better deal, but personally the money and time would seem better spent in other ways for me. With EFI, you get a little more control and little more tuneability, but is it worth it? Well, maybe.

i think ulitmately it would be worth it in the long run. for improved drivability, more tunability and since i can put it on another engine later if i want i think its worth it. EFI prices have come down, especially on TBI system since port injection has increased in popularity and there are more systems coming out every year. then again we put like 400+ bucks into the cooling system (aluminum core plastic tank caprice radiator 100 bucks, black magic fan 200 bucks, and a stainless steel upper radiator hose 80 bucks {the old one was too short to use}, then coolant and blah blah blah) so i dont think 1300 buck for a new fuel delivery system is that much (all things relative). dont get me wrong, i am thrifty and even down right cheap sometimes but just about every penny i've put into the car has been worth the "investment" aside from getting the old 200 POS tranny rebuilt before getting a pre 81 th-350....but thats another story. and since i'm keeping this car as long as i can i'm not gonna go bottom of the barrel cheap. i at least check stuff out as much as possible before forking over the cash. sometimes i spend more but its a trade off to have the car the way I want it. rebuilt engine, better cam for that engine, holley TBI kit, rebuilt distributor (sorry 140,000+ miles distributor isnt going in an essentially new engine, i'll keep it as a spare) we're talking about 3000 bucks. thats a little much but considering how long these engines can last if you take care of them its worth it. 3000 bucks over say 15 years.....200 bucks a year. thats also not including headers, TRUE dual exhaust (the engine has gotta breath for a 650 CFM TBI), ignition box, and all those odds and ends you never remember till the last minute.


yes i've put a lot of thought into this! lol too much perhaps.


this engine has moved the car for 18 years and doesnt seem to show any signs of stopping any time soon so i'll see if i can go 20 or even 25 years with it. i think doing this with the car is more of a reward to the car for being so good to me. it deserves it i think.
 
Originally posted by MY85pontiac
i have the intake and i had the carb (till it had a meeting with a ten pound sledge hammer) off my 4.1 (the 4.1 is in my 82 GP LJ but i'm putting something else in there, maybe a pontiac 400, not sure. want the 4.1? come get it!). then i'd have to get different secondary rods and go through the rather annoying task of "tuning" it right and to be honest i am really not wanting to do that anymore. also i MIGHT go with their 650 CFM 4 bbl kit and i'll probably wind up getting an aftermarket intake for improved breathing capability.


Did I ready you right that your giving away a 4.1L engine?

Mike in Cincinnati is interested :D
 
sure if you have something to trade i might be interested in. you pull it out though, i dont have an engine lift.
 
As far as I can see an injection/ignition system with all the parameters accessable through a lap top is a tuners dream come true. :cool:

Go for it.:D
 
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