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Dusterbd13
Dusterbd13 Reader
1/5/12 6:49 a.m.

ok, ive already got a good bit of my parts amassed for my EFI conversion on my small block mopar.

using a painless wiring harness for a tuned port corvette dodge magnum 5.9 fuel rails ford racing 30lb injectors 7727 ECM Edelbrock Victor Jr. converted to EFI

still need a fuel pump, return line, regulator, various sensors, and a throttle body (4 barell style)

also need injector bungs to weld into my intake.

any recomendation for the bungs? looking at quality and price. any reccomendations on a fuel pump? this car puts out just under 400 to the rear wheels at the moment. will a 3/8 feed and 5/16 return be enough? what kind of regulator shoudl i be going with? i was looking at the corvette C5 regulator/filter assembly, but remember that the TPI cars had a vacuum reference to them. the C5 doesnt. any great deal on 4bbl throttle bodys with GM TPS and IAC that i shopuld know about?

lastly, what to do about a knock sensor. i know the ECM looks for one, i just dont know which one to choose. theres so many.

thanks for any direction you guys can give me.

michael

Aeromoto
Aeromoto Reader
1/5/12 6:54 a.m.

Not a 4 barrel, but I believe a TBI 454 throttle body flows over 750cfm. you can buy plates to adapt them to 4 barrel manifolds.

Curmudgeon
Curmudgeon SuperDork
1/5/12 7:05 a.m.

http://www.rossmachineracing.com/injectorbungs.html

The FPR will need to be as near the front as possible. Vacuum type is fine. The actual regulator will depend on your mounting requirements.

Fuel pumps; there's a ton of 'em around. The MSD inline pump works fine and is cheap (~$110.00) but damn it's noisy. Your line sizes should be fine. Just make sure there's no kinks in them.

Air door; ya got me there. Just about everything I've seen or messed with has had regular throttle bodies or one of those TBI units with the low pressure injector, not really conducive to good performance.

Knock sensor: are you using MegaSquirt? If so, those are set up to use dirt common GM type sensors for everything. If you are using something different such as an OE type ECM, I'd get the sensor that's listed for the car it came out of.

BigD
BigD Reader
1/5/12 7:20 a.m.

I don't have much domestic experience but I think most cars use the same Bosch knock sensor with different connectors.

But I'd tread carefully with knock sensing. It's not universal. The knock frequency for each engine is different. If you've looked into this then ignore me. Otherwise, it may be better to leave off the knock sensors if you don't have a way to tune the filter, or it may pull timing for false positives.

Ranger50
Ranger50 Dork
1/5/12 7:47 a.m.

Are you already EFI or no, pertaining to your vehicle? If you are already EFI, just put in a 255lph intank replacement pump in. If not, I would just put on something like an Aeromotive A1000 pump, sometimes you can get these used and burned up for a song and get it rebuilt, or one of those new Holley EFI pumps and plumb it up accordingly.

I don't forsee a problem using the vette FPR/filter. So what if you have a vacuum referenced regulator, block it off. Which I am having a problem with as Mopar doesn't use one typically at the rail, it is on the fuel pump. GM does, but it isn't tied into any computer functions.

TB, why not use a 4-bbl elbow, Ford TB with GM sensors attached? All the AM computers typically use GM sensors. So, based on that fact, there are plenty of adapters for going from Ford to GM bolt patterns.

Knock, write it out with your program. You will just end up chasing your tail over it. Run GOOD gas, aka cheap out on cheap swill or lesser then needed octane, and it won't be a problem.

Aeromoto
Aeromoto Reader
1/5/12 10:26 a.m.

As far as using a gm TBI throttle body, no law states that you couldn't remove the low pressure injectors and use it simply as a throttle body.

Aeromoto
Aeromoto Reader
1/5/12 10:28 a.m.

http://www.jegs.com/i/Trans%20Dapt/969/2201/10002/-1?CT=999

MadScientistMatt
MadScientistMatt SuperDork
1/5/12 11:53 a.m.
Dusterbd13 wrote: any recomendation for the bungs? looking at quality and price.

I second the one about Ross Machine Racing. They're a pretty good source if you're using a rail type fuel system.

any reccomendations on a fuel pump? this car puts out just under 400 to the rear wheels at the moment.

A Walbro GSL392 would be about perfect - cheap, readily available, and the right size.

will a 3/8 feed and 5/16 return be enough?

It should be. You could probably use the stock fuel line as a return.

what kind of regulator shoudl i be going with? i was looking at the corvette C5 regulator/filter assembly, but remember that the TPI cars had a vacuum reference to them. the C5 doesnt.

I'd go vacuum referenced, definitely. If you want to go aftermarket, an SX or Aeromotive regulator would be good; if you're looking for one at the parts store, try asking for one from a '82 Datsun 280ZX (either turbo or NA, doesn't matter). The 280ZX regulator is one of the few OEM ones that has hose fittings and a decent price tag.

any great deal on 4bbl throttle bodys with GM TPS and IAC that i shopuld know about?

I'd probably go with BBK, Scorpion, or Accufab.

lastly, what to do about a knock sensor. i know the ECM looks for one, i just dont know which one to choose. theres so many.

As others have noted, they are application specific, but I'd imagine one off a TPI smallblock is a good bet. Note that you WILL need the accompanying knock filter module; you can't wire it up straight to the ECU. GM knock detection was pretty rudimentary back then; it's not in the same league as what you'd see on an LS1.

I take it you're already aware of the Lean Burn / 7 pin HEI trick for setting up the ignition.

MadScientistMatt
MadScientistMatt SuperDork
1/5/12 11:55 a.m.
Aeromoto wrote: As far as using a gm TBI throttle body, no law states that you couldn't remove the low pressure injectors and use it simply as a throttle body.

They don't flow enough air to support 400 rear wheel HP, though; they're generally the EFI equivalent of a two barrel smog carb.

Ranger's suggestion of an elbow (Edelbrock has some pretty good castings) and single barrel throttle body is also a good one and can be cheaper than an aftermarket four barrel.

Aeromoto
Aeromoto Reader
1/5/12 12:01 p.m.
MadScientistMatt wrote:
Aeromoto wrote: As far as using a gm TBI throttle body, no law states that you couldn't remove the low pressure injectors and use it simply as a throttle body.
They don't flow enough air to support 400 rear wheel HP, though; they're generally the EFI equivalent of a two barrel smog carb. Ranger's suggestion of an elbow (Edelbrock has some pretty good castings) and single barrel throttle body is also a good one and can be cheaper than an aftermarket four barrel.

Hmmm...., Mercruiser is currently offering the GM 454 TBI up to 485 hp.

MadScientistMatt
MadScientistMatt SuperDork
1/5/12 12:31 p.m.
Aeromoto wrote: Hmmm...., Mercruiser is currently offering the GM 454 TBI up to 485 hp.

The one I saw on their website is a tuned port setup. It's possible they may have sold a high powered 454 TBI, but I'm pretty certain it wouldn't have used a standard GM TBI; it probably either used some sort of four barrel TBI or some sort of unique hardware with larger bores. The truck 454 TBI was only 250 hp, and you have to port the snot out of their TBI if you want to make good power with one of those setups.

Aeromoto
Aeromoto Reader
1/5/12 2:36 p.m.

They still sell the 485hp TBI through their reman division, just helped my buddy swap a fresh pair into his Sea Ray. They came orig. to the boat in yr 2000. Brand new, Merc no longer even offers the 454, all their new big blocks are 502s with a ramjet style efi that is similar to the old TPI.

All TBI stuff aside, I'm thinking that I'd go with a tunnel ram topped with 2 Ford 5.8L truck throttle bodies. It would look like some kind of mutant Hilborn or Kinsler setup from the 60s.

Ranger50
Ranger50 Dork
1/5/12 2:47 p.m.

In reply to Aeromoto:

No offense, but I wouldn't put TBI anything on a berkeleying billycart!

Dusterbd13
Dusterbd13 Reader
1/5/12 2:47 p.m.
MadScientistMatt wrote:
Dusterbd13 wrote: any recomendation for the bungs? looking at quality and price.
I second the one about Ross Machine Racing. They're a pretty good source if you're using a rail type fuel system.
any reccomendations on a fuel pump? this car puts out just under 400 to the rear wheels at the moment.
A Walbro GSL392 would be about perfect - cheap, readily available, and the right size.
will a 3/8 feed and 5/16 return be enough?
It should be. You could probably use the stock fuel line as a return.
what kind of regulator shoudl i be going with? i was looking at the corvette C5 regulator/filter assembly, but remember that the TPI cars had a vacuum reference to them. the C5 doesnt.
I'd go vacuum referenced, definitely. If you want to go aftermarket, an SX or Aeromotive regulator would be good; if you're looking for one at the parts store, try asking for one from a '82 Datsun 280ZX (either turbo or NA, doesn't matter). The 280ZX regulator is one of the few OEM ones that has hose fittings and a decent price tag.
any great deal on 4bbl throttle bodys with GM TPS and IAC that i shopuld know about?
I'd probably go with BBK, Scorpion, or Accufab.
lastly, what to do about a knock sensor. i know the ECM looks for one, i just dont know which one to choose. theres so many.
As others have noted, they are application specific, but I'd imagine one off a TPI smallblock is a good bet. Note that you WILL need the accompanying knock filter module; you can't wire it up straight to the ECU. GM knock detection was pretty rudimentary back then; it's not in the same league as what you'd see on an LS1. I take it you're already aware of the Lean Burn / 7 pin HEI trick for setting up the ignition.

what kind of fuel pressure is the ZX regulator set to? i planned on ~60 PSI of operating pressure, which is why i only went with 30lb ford injectors. i was also thinking the knock sensor and filter from an early 90's TPI setup. my only fear is that it may pick up noise for the solid roller cam.

ill buy the ross machine pieces.

and please, do tell about the ignition system trick. i was planning on trying to figure out something with the lean bburn distributor, as its factory locked out.

is that fuel pum in tank oor external? noisy or quiet?

please, keep all this discussion going. this is the board i get the most help from on this kind of thing. you guys are the ones that inspired me to inject this pig. should make it much more fun for the autoX and track days when i dont hhave to fight carb issues.

Michael

MadScientistMatt
MadScientistMatt SuperDork
1/6/12 7:42 a.m.
Dusterbd13 wrote: what kind of fuel pressure is the ZX regulator set to? i planned on ~60 PSI of operating pressure, which is why i only went with 30lb ford injectors.

Pretty sure it's at 43.5 psi - I'm not aware of much in the way of easy to plumb up high pressure stock regulators. You're probably going to need an aftermarket regulator.

i was also thinking the knock sensor and filter from an early 90's TPI setup. my only fear is that it may pick up noise for the solid roller cam.

With the combination of an '80s GM ECU and a solid roller cam, I would simply give up on knock sensing - I don't think you will be able to make it work. Maybe if you used a J&S Safeguard.

and please, do tell about the ignition system trick. i was planning on trying to figure out something with the lean bburn distributor, as its factory locked out.

This is written for MegaSquirt, but would also work for a GM ECM.

http://www.diyautotune.com/tech_articles/how_to_megasquirt_your_vintage_mopar_engine.htm

is that fuel pump in tank oor external? noisy or quiet?

It can be set up either in the tank or external. It's louder than OEM but not as loud as, say, an A1000, and you can muffle it to reasonable levels.

Dusterbd13
Dusterbd13 Reader
1/6/12 7:52 a.m.

you rock, matt.

thank you so much. now its time to scavenge an HEI out of the junkyard, too.

any reccomendations on a low cost, quality high pressure regulator? i "think" ill need the 60lb of pressure to make my 400 horses on 30lb injectors. i just dont think that the 43.5 psi would do it. am i correct?

Michael

MadScientistMatt
MadScientistMatt SuperDork
1/6/12 8:33 a.m.

Yes, you will need a little more pressure to make 400 hp at the wheels - 30 lb/hr injectors would be enough for 400 hp at the crank at 43.5 psi.

I may be a bit biased :) but I recommend buying this regulator:

http://www.diyautotune.com/catalog/sx-performance-15404-an-fuel-pressure-regulator-p-300.html

erohslc
erohslc HalfDork
1/6/12 12:36 p.m.

Unless you are dead set on welding in the bungs, consider epoxy or JB Weld.
The bungs are not highly stressed, their main job is to hold the injectors in alignment to allow the bottom O-rings to seal to manifold pressure, and provide a mechanical stop that prevents the fuel pressure from spitting the injectors free of the rail. So unless you are running like 2-3 Bar of turbo/supercharging, not so critical. The fuel rail is where you need to take pains, as the 43.5 psi fuel pressure will be trying to spit the injectors out of the rail. And of course any kind of fuel leak at that pressure is a bad day in the making.
So the rail must both maintain alignment of injectors to prevent fuel pressure leaks at O-rings, and resist the pressure of the 4 injectors trying to seperate from the rail.
The fuel rail can be precision machined as one piece so that the axes of the injector pockets are all parallel and spaced evenly.
But fitting and welding bungs into the manifold, can be hard to maintain that precision.
Once welded, if you find a problem, well, have to un-weld the bung(s) and refit them. ;)
But if you use epoxy, you can assemble the injectors, rails, rail retainer hardware, and bungs to the manifold, they tend to 'self-align'. You can check for binding/alignment, make adjustments (even egg-shaped holes in manifold if needed), and then add adhesive and let it cure.

Carter

Dusterbd13
Dusterbd13 Reader
1/6/12 3:14 p.m.

id seen references to JB welding the bungs in place, but was kind of wondering on the durability of that setup. this is primarily a street car/toy. sees probably 4K a year, and lots of long trips from home. thats why im trying to stay with readily availibble factory parts if at all possible.

what intrigues me about the JB weld idea is that its a LOT prettier than tigged in bungs. which this car has to be pretty and clean, too.

i am not boosted. yet. when i do, i will be running a centrifugal, at about 6-8 lbs. will the JB hold up to that for long term?

again, just worried about longevity. if its really not a concrern, let me know. id be more than willing to do it that way.

michael

Curmudgeon
Curmudgeon SuperDork
1/6/12 8:17 p.m.

I have seen spark plug tubes held in the cylinder head with red Loctite. No reason that wouldn't work with injector bungs, you just have to make sure the toledances are tight (should be a tap fit). If that's not possible then JB Weld or epoxy should do the trick.

Woops, just reads the word 'boosted'. Weld them in.

erohslc
erohslc HalfDork
1/6/12 8:45 p.m.

In reply to Curmudgeon: Jah, I agree, Boost + JBWeld = Fail
But I wonder why no one has made bungs with threads on the outside?
Make them out of a piece of hex bar stock, so that it's easy to use a socket to install them.
Maybe there is an off-the-shelf fitting in brass or steel that could be 'repurposed'?
Maybe in a suitable NPT size, then taps would be commonly and cheaply available.

Dusterbd13
Dusterbd13 Reader
1/6/12 9:17 p.m.

they do make thread in bungs. theyre just ugly.

and i probably will never get around to going with boost, to be honest.

the thought of ITB's and crossrams intrigue me too much.

but that is WAY down the road.

for a non boost application, how would the JB hold up? does it need to be a tap fit in this application as well, or is there some fashon of prep i should perform?

michael

turboswede
turboswede GRM+ Memberand SuperDork
1/6/12 9:18 p.m.

MSD made bungs like you're describing, but they've discontinued them.

Rob_Mopar
Rob_Mopar Dork
1/6/12 9:55 p.m.

FAST lists epoxying their universal injector bungs (# 307017) in the manifold as an option. Haven't tried it for this use but JB has gotten good reviews for back filling overly aggressive head porting.

turboswede
turboswede GRM+ Memberand SuperDork
1/6/12 10:23 p.m.

Btw, CIS to EFI conversions usually require thread in bungs.

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