i am look into making a custom efi setup for my 401 nailhead, one thing i will need to do is change over to gm hei, i will be using a lt1 ecu,harness, and componants, has anyone else looked into this setup. i will making a custom intake, and buying bigger injectors and custom injector rail, i can buy a complete lt1 engine/harness /ecu out a 96 roadmaster for $400.. any help would be appreciated. thanks paul in mass
paul, I would look at using a megasquirt; much more user-friendly and probably cheaper when you look at add the cost of editing software for the LT-1 ECU.
yeah megasquirt is cheapest but do not control transmissions if you need that you can use your intake you just need to drill it for injectors and use a efi throttle body there is company called aeromotive that sells a 4bb one for 100 bucks lt1 and ls1 ecms wont work the use crank senders you will need parts off a tpi camaro firebird etc and have it reprogrammed and now for the worst part the factory fuel pump and tank will not work here you have 3 choices A: cut your factory tank and weld a sump in and put a external pump B: use a fuel cell C: use a late model caprice classic gas tank and modify the filler neck and run a new internal pump. you cannot run a interanl pump with factory tank it is not baffled and also you need to have a vent tube set up with efi otherwise you will crack the tank your looking at about 1500 2000 bucks at least
I have been looking into setting up an old Algon unit I have much like the hilborns. I am trying to use as much stuff from Northstar Caddies as I can as that is what I work on and can get my hands on the parts quick and cheap. I don't think the injectors will flow quite enough but since I have them I will try them and see where my duty cycle ends up. I plan on using the intake spacers such as sold by NWSpeed/Eelco and tapping them for the injectors. When I spoke with the Guys from Hilborn at Columbus this year, I saw they are doing the same thing. If I build my own ecm from Megasquirt, I might be able to get it running for about $400-500 dollars out of pocket, then whatever the upgrades will cost such as bigger injectors, etc... It is nice having access to parts at work and a good collection at home :beer I found that the 4.6 Northstar fuel rail only needs to be shortened about 1 1/2 inch between the center injectors to get the injectors all into Nailhead intake ports/runners. Then cut the horseshoe end and let them roll down. It doesn't look perfect but should get the unit operational and then I can make a nicer looking set up. My plan is non sequential and use only the minimum sensors. Hopefully a TPS, O2, Coolant temp, and MAP. If it works ok, I might make an intake with a regular single large throttle body hidden under a stock style air cleaner. Well, I have all winter to make something work.
I have been looking for a throttle valve but can only find them in the $500 + range. I looked on there web site and could not find any under $500. o No: Could you post a link? Mike
i have acess to a machine shop than will drill my intake and weld in injector bungs. i will need to run a gm hei setup. i thought thier was a link to swap over to gm hei for a nailhead. also is thier a way to get past the cranksensor and not run one? all new ground for me tring to make this work, if thier is a will thier is a way.. any help would be greatly appreciated
http://www.auto-nomics.com/cgi-bin/showresults?a=detail&part=10850-002-D sorry got the sites confused as for hei msd makes a hei dist for nailheads on ebay and nwspeed sells them too
OR you could go with these guys and have your ignition, and EFI setup all covered: http://www.getfuelinjected.com/ wes
not very cheap though when you could piece it together for half that and still doesnt control computer controlled tranny
Paul, I think if you go nonsequential you can avoid a cam sensor. The cranksensor can be the same as your tach signal. The down side is slightly less performance and efficiency, but should still be better than carburation if set up right. Many early setups were this style, throttle body setups run the same basic principle. Some late models default to this if there is a fault with the crank or cam sensors. I am not sure you 'need' an HEI set up although it should obviously help. Doc, now you are giving away my secret plans for my 6x2 intake...
Efi I think that if I did this conversion, I probably would go with the throttle body type [900cfm or so] on a EElco single 4 manifold. Mo simple and easier to work with. I just wonder what the differencein power would be. Joe, us old street rats gotta stick together.
Electronic controlled trannies are overrated, unless you are wanting a 4L80E you aren't going to do any better than a TH400 for something thats going to hold up to nailhead power without being beefed. Big Stuff 3 does trannys, I think MoTec does trannys aswell. Otherwise you'll need a TCU from TCI, PCS, or a stand alone BS3 to control it. I'd try to use LS1 stuff rather than LT1 since its more advanced and you can use a mag pickup distibutor for a cam sync signal. The crank trigger ring can be purchaced from GM and adapted to the balancer with a custom bracket to hold the sensor.
yes but a th400 has no od is the only downside agree with the ls1 over lt1 but a tune port setup is going to be easiest they run a bank to bank setup only about 3 sensors to run it and for a 100 bucks a factory dist can be converted to hei or you can buy a msd hie or pertronix with ls1 your going to have to run a maf which isnt easy to tune
fast controls trannies too for a aftermarket ecm there not to bad pricewise like 1k megasqurit is supposed to be building a tranny control system too megasquirt for the broke man is best
i have been looking into megasquirt and into fast.. i have a complete setup from a lt1 but i dont think i will be using it. i am looking for a single 4 barrel aluminum intake, if anyone has one let me know. i can run bank to bank injection like the old tpi setup without a crank or a cam sensor with megasquirt. but with fast i can run sequential injection with the hei setup. i will most likely run a universal crank trigger and that should simplify everything. i talked to the guys over at autonomtics and said he can send me a throttle body(air gate) with the tps,iac valve for $250.00.. i dident think that was to bad at all. i will running a gm coolant and air temp. i am tring to plan this out very carefully and tring to pick a system that will be easy to tune and compatable with any setups i plan in the near future(turbo in the rear of car) i will be running a th400 so i dont care about the tranny control but i do like the fact with the fast you can take advance out or in anytime you like and very easy to do. i am feeling that the megasquirt is alot harder to tune because of all the files you have to find or download. does anyone run measquirt? i have a friend who runs a twin turbo chevelle and says he had his chevelle tune in 1 hour with fast, that is pretty sweet. well any help greatly apprecaited, thanks again paul in mass
single 4 There is a rumor that EElco is coming out with a single 4 version of thier 2x4 manifold. We need to pester them about it. we need all the help we can get. p
Those look pretty cool, too bad they don't offer them in an AFB style, that would be the cats pajamas as a dual quad set up. I know MOON Equip offers a 2bbl style that resembles the old Stromberg 94-97s for guys with early style hotrods. Personally I am after the 'stack' style mechanical injector look, but running some EFI injectors under an old 6x2 set up would make them runn much better and keep the look. I get all sorts of crazy ideas at work when I have no real 'work' to do and piles of old parts on the bench.
only thing with the carb style injections systems is they work like an old chevy truck with tbi and really dont offer alot of advantages over a carb espicailly for the price of them on a side note you can make a 88-95 chevy truck system work pretty cheap just need to change injectors to larger ones but they are a 2bb design as for using a th400 if i were going the the fast system i would find me a used 4l80e from a wrecked 3/4 ton 1 ton gm truck they are a much stonger trans and are 4speed od
