It’s great you know so much about crossfire injection. I’m an Acura master tech. My uncle has an 83 Daytona 500 trans am. I think it would be better for him to take you his car than me marking special tools to dial it in. Thanks for making yourself available to the public trough these videos.
@@Joesmusclecargarage I’ll let him know he lives in Yuma, I put a new distributor and a vacuum leak to the map sensor. It’s ok but I know it could be much better, and it’s pretty clean
@@Joesmusclecargarage Cool I’ll talk to him, I’ll fix a couple of leaks, align the rear hatch and fix the rattles in the doors, he is really cool, he would probably let you drive it for a month. He has to many cars.
@@Joesmusclecargarage He will pay you of coarse, I will get everything sorted out, cosmetically it’s nice, and it only has like 70k miles, it just needs some fine tuning, I’ll make sure it has no vacuum leaks.
Im currently working on a 84 Corvette with the CFI set up... the car ran great a couple years ago,but wasn't driven much. I've been chipping away at replacing parts trying to get it to run right. Had the dreaded code 42, but was able to get rid if that, but unfortunately rhe car is still runntlike crap. Looking for other options. I've done a tune up( cap, rotor, Ignition module, wires, plugs....) also had a battery drain issue which led me to replace the battery. I found a really bad ground while in there and replaced that too. This ol girl is just running rough. Think it may be vaccum related, but after watching tour videos and a few others, I've come to the conclusion that it could be anything from vaccum to ECM....lol guess I'll just keep going. Wish you were in Las Vegas hahahaha. I really like rhe CFI set up because its unique and hated... really wanna get it running smoothly.
@@DarrellHewko Add tension to increase. But DO NOT adjust the pressure without a gauge on it. As little as 1/8 turn can bump the pressure up as much as 5-6psi, and every pump/regulator combination is different.
Do you know if power can be made with the crossfire setup? I just got an 82 z/28, and I know everyone on the web says to gut it but I like the gimmick just want it to be a bit more peppy. Getting it running well will help and these are great videos but I should just ask if you know of any tricks to get a bit mote out of them?
Of course. Port the base, bump the timing and fuel pressure. The rest is common stuff that applies to any other car; exhaust, gears, converter, cam, etc. My current 83 went from 16.50s to 14.40s, still running the stock cam, and still gets 17mpg city and 25mpg hwy. It’s easier and cheaper to get power out of a CFI car than a TPI car. The ones that say “gut it”, or slap a carb on it, have more than likely never seen a CFI car in person, much less driven or worked on one. It’s a different world now than it was 40 years ago, when nobody understood fuel injection or how to work on them.
I just realized my butterfly valves are open 1/8 inch I was wondering what could make this happen how, so I get both butterfly valves to go back to normal? maybe I have tension on my throttle cable? because it's giving enough gas for the amount that the valves are open. it's like the gas pedal is slightly down opening the butterfly valves and having a high idle.
@@Joesmusclecargarage ok so I did this and maybe I 1/8 inch was a little exaggerated. from pictures i am seeing online looks like the butterfly valves should be a little more closed but the car is dumping so much fuel into the TBIs. It's been sitting since 2014. none of the tamper plugs have ever been removed. I put all new gaskets on changed most of the Vacuum lines I put new EGR Valve I changed the 2 IACVs and maybe it lowered the RPMs just a little. at one point I thought it was down to the TPS the car was idling up and down. but ever since I touch the TPS the idle went back to high. I was really hoping I could understand this crossfire set up. but I keep coming to dead ends. My dad's birthday is coming up in 2 months and he thinks I sold the car a year ago. I have been on the forums asking people for months they just keep telling me to change parts until I find the problem. Anyone I ask if they know how to work on a crossfire injection, they laugh at me.
Hey Joe. Great Videos! I need to make the fuel gauge setup in order to set my pressure. I have the gauge, and I plan to use hoses like yours in the video. What ends do I need to screw into the TB's? I've heard its 3/8 inverted flare, but I don't want to gaggle anything up. Thanks!
It’s just a standard 3/8” steel fuel line, with a 0-15psi gauge. Be careful going over 13psi if your regulator diaphragm hasn’t been replaced in a while.
hello joe, I have an 84 corvette with crossfire. main throttle body works ok, the slave is not working(dry). where would you suggest I start.where would you look first. I have no idea where to begin.I did put a noid light on the slave and it is firing.
Just so I understand and we’re both on the same page; I’m assuming you mean the injector on the slave (passenger side/front) TB is not spraying? If you have power and ground to the injector, and it is pulsing and verified with a noid light, the coil inside the injector could be bad. It would have to be completely clogged all of a sudden for it not to spray any fuel whatsoever, and that is very unlikely. You can apply power to the injector and see if you can hear it clicking. If the master is spraying properly, that is the last stop the fuel makes before it is returned to the tank. I would start by actuating the injector with a battery, either 9V or a 12V power source. I do have a good spare pair of L05 350 injectors if you end up needing them.
@@Joesmusclecargarage Thanks for the reply Joe, The noid light did show pulsing.I will try with the 9 vole and listen for the clicking.I have 2 rebuild kits but have never rebuilt one before.I guess I have nothing to lose trying a rebuild.Your thoughts on difficulty to rebuild.Thank You.
@@williampalladino3663 The TBs themselves are super easy to rebuild. Just a gasket and a few seals. It’s very self explanatory once you open it up. Make sure you clean the inlet screens on the injectors while it’s apart.
Thanks for the video. Do I knock out the aluminum/metal housing located at the base of the injector or the black rubber smaller plug that's located in the aluminum/metal housing enclosure extending out of the fuel injector?
@@Joesmusclecargarage At the base of the regulator, there is a knockout plug. In the center of the knockout plug is a small circular rubber cover of some sort... My question is, do I remove the rubber cover, or do I remove the metal knockout? I can send a photo if you like.
Joe on my injector head (1984 Corvette, L83), after removing the metal knockout plug I noticed a small vertical slit on the side of the housing unit which I’m able to visually see the regulator spring. The spring sits on top of the nut that is used to adjust the fuel pressure, however, a part of it extends slightly outside the slit in the housing unit. I’m unable to turn/adjust the regulator. Should I disassemble the injector head and try to set it so that it stays inside the unit?
To adjust the FPR correctly, you need to either buy or make a tool to turn the adjustment screw while the engine is running and while you have a fuel pressure gauge between the two throttle bodies, as mentioned in the video. The screw is very sensitive, and it doesn’t take much to make a big change.
Oh ok, so its the fitting that goes in to the throttle body that its a metric size? Because ive looking for a line for my throttle body and i can't find it, i had to watch your video again and i think i see a fitting that the line fits in to? Sorry im trying to get a fuel gauge on my Trans am when i replace all the intake gaskets, since my car now is falling on its face when i accelerate. Im trying to buy all the stuff before i start taking it apart. Im really happy your making this videos, especially the part when u say that people will rather put a carb instead of figuring out how to make them run good. I like to see the cfi run good, especially when ive heard that they tried to do it like the 302 crossram that camaros used in the 60s to race them and it had 2 carburetors. And also its a piece of history that we dont see everyday
I have a '83 Trans am with Crossfire. The only real problem is cold starts require a lot of cranking. It will finally start to stumble and then fire and run normal. Plenty of pull and smooth running on the highway. Is there any reason to check the fuel pressure? Could it be bad gas? Plugs? Plugged fuel filter? New idle air valves 50 miles ago. Great site!
@blackTtop There’s always a reason to check fuel pressure on a CFI. They were set low (8-10) from the factory. They run like shit if they’re not up around 13-14.
On my 84 corvette I put a 85 fuel pump and had the throttle bodies rebuilt and he adjusted it to about 14lbs. So my question is do I need a fuel pressure regulator because the 85 pump put out more pressure then the 84 pump? Or just Leave it alone.
14psi is fine, but it is at the “safe” limit for the factory FPR. Any more than 14 and you should consider eliminating the factory FPR and running an external regulator.
DCS sells machined aluminum plates that go in place of the FPR and accumulator. Most of their products are out of stock, and likely out of production though. You can easily fabricate some plates though.
Hey Joe, do you do any work on 82 Corvettes? I have several with less than 5k miles that I am trying to salvage from being stored since the 80’s. I could use any help and advice I can get. The one I am working with now has a very low idle and will not stay running. I’m not a mechanic. Any ideas after having replaced fuel (and brakes)?
What’s your question? If you’re asking what your fuel pressure should be, 16psi is unnecessary, and are on the edge of what the FPR diaphragm will hold. If all you have is the manifold, rockers, and exhaust, no more than 14psi is necessary.
It’s great you know so much about crossfire injection. I’m an Acura master tech. My uncle has an 83 Daytona 500 trans am. I think it would be better for him to take you his car than me marking special tools to dial it in. Thanks for making yourself available to the public trough these videos.
If you were in AZ, I’d be all over it.
@@Joesmusclecargarage
I’ll let him know he lives in Yuma, I put a new distributor and a vacuum leak to the map sensor. It’s ok but I know it could be much better, and it’s pretty clean
No kidding? It’s a few hour drive from Phoenix, but I’d be happy to help out.
@@Joesmusclecargarage
Cool I’ll talk to him, I’ll fix a couple of leaks, align the rear hatch and fix the rattles in the doors, he is really cool, he would probably let you drive it for a month. He has to many cars.
@@Joesmusclecargarage
He will pay you of coarse, I will get everything sorted out, cosmetically it’s nice, and it only has like 70k miles, it just needs some fine tuning, I’ll make sure it has no vacuum leaks.
Thank you for making this video.
This is the most informative video I've ever seen on the 82 Corvette engine!
Thank you so much for sharing your knowledge of these systems.
Thanks for taking the time to explain and post 🙏😁😷
Very useful post. Thank you!
I love when I learn something new, good information
Im currently working on a 84 Corvette with the CFI set up... the car ran great a couple years ago,but wasn't driven much. I've been chipping away at replacing parts trying to get it to run right. Had the dreaded code 42, but was able to get rid if that, but unfortunately rhe car is still runntlike crap. Looking for other options. I've done a tune up( cap, rotor, Ignition module, wires, plugs....) also had a battery drain issue which led me to replace the battery. I found a really bad ground while in there and replaced that too. This ol girl is just running rough. Think it may be vaccum related, but after watching tour videos and a few others, I've come to the conclusion that it could be anything from vaccum to ECM....lol guess I'll just keep going. Wish you were in Las Vegas hahahaha. I really like rhe CFI set up because its unique and hated... really wanna get it running smoothly.
Nice vids just bought an 82 Camaro. Definitely needs a cross fire tune up.
Good video. Thanks.
Good job thanks for the video
Do you add tension to the spring to increase the fout pressure (clockwise from the bottom) or decrease spring tension to increase pressure?
@@DarrellHewko Add tension to increase. But DO NOT adjust the pressure without a gauge on it. As little as 1/8 turn can bump the pressure up as much as 5-6psi, and every pump/regulator combination is different.
Do you know if power can be made with the crossfire setup? I just got an 82 z/28, and I know everyone on the web says to gut it but I like the gimmick just want it to be a bit more peppy. Getting it running well will help and these are great videos but I should just ask if you know of any tricks to get a bit mote out of them?
Of course. Port the base, bump the timing and fuel pressure. The rest is common stuff that applies to any other car; exhaust, gears, converter, cam, etc. My current 83 went from 16.50s to 14.40s, still running the stock cam, and still gets 17mpg city and 25mpg hwy. It’s easier and cheaper to get power out of a CFI car than a TPI car. The ones that say “gut it”, or slap a carb on it, have more than likely never seen a CFI car in person, much less driven or worked on one. It’s a different world now than it was 40 years ago, when nobody understood fuel injection or how to work on them.
do you have to do both sides and thanks for the video.
There is only one regulator, and it is on the rear (master) TB.
Possible to adjust pressure without a gauge. Approximately how much do you need to turn the screw?
No it’s not possible. As far as how much to “turn the screw”, it depends on what the FP is at before you adjust it. Do it right.
I just realized my butterfly valves are open 1/8 inch I was wondering what could make this happen how, so I get both butterfly valves to go back to normal? maybe I have tension on my throttle cable? because it's giving enough gas for the amount that the valves are open. it's like the gas pedal is slightly down opening the butterfly valves and having a high idle.
Disconnect the cable and see if the blades close. If they don’t, find out what’s holding them open. Are both TBs open an equal amount?
@@Joesmusclecargarage ok so I did this and maybe I 1/8 inch was a little exaggerated. from pictures i am seeing online looks like the butterfly valves should be a little more closed but the car is dumping so much fuel into the TBIs. It's been sitting since 2014. none of the tamper plugs have ever been removed. I put all new gaskets on changed most of the Vacuum lines I put new EGR Valve I changed the 2 IACVs and maybe it lowered the RPMs just a little. at one point I thought it was down to the TPS the car was idling up and down. but ever since I touch the TPS the idle went back to high. I was really hoping I could understand this crossfire set up. but I keep coming to dead ends. My dad's birthday is coming up in 2 months and he thinks I sold the car a year ago. I have been on the forums asking people for months they just keep telling me to change parts until I find the problem. Anyone I ask if they know how to work on a crossfire injection, they laugh at me.
is the FP only adjusted on the primary?
Yes. The fuel pressure regulator is housed in the master TB (drivers side).
@@Joesmusclecargarage Thank you for clarifying this.
What should the fuel pressure be coming out of the pump?
The factory specified range is 9-13psi. Most stock to mild cars run best at 13-14psi.
Hey Joe. Great Videos!
I need to make the fuel gauge setup in order to set my pressure. I have the gauge, and I plan to use hoses like yours in the video. What ends do I need to screw into the TB's? I've heard its 3/8 inverted flare, but I don't want to gaggle anything up.
Thanks!
It’s just a standard 3/8” steel fuel line, with a 0-15psi gauge. Be careful going over 13psi if your regulator diaphragm hasn’t been replaced in a while.
hello joe, I have an 84 corvette with crossfire. main throttle body works ok, the slave is not working(dry). where would you suggest I start.where would you look first. I have no idea where to begin.I did put a noid light on the slave and it is firing.
Just so I understand and we’re both on the same page; I’m assuming you mean the injector on the slave (passenger side/front) TB is not spraying? If you have power and ground to the injector, and it is pulsing and verified with a noid light, the coil inside the injector could be bad. It would have to be completely clogged all of a sudden for it not to spray any fuel whatsoever, and that is very unlikely. You can apply power to the injector and see if you can hear it clicking. If the master is spraying properly, that is the last stop the fuel makes before it is returned to the tank. I would start by actuating the injector with a battery, either 9V or a 12V power source. I do have a good spare pair of L05 350 injectors if you end up needing them.
@@Joesmusclecargarage Thanks for the reply Joe, The noid light did show pulsing.I will try with the 9 vole and listen for the clicking.I have 2 rebuild kits but have never rebuilt one before.I guess I have nothing to lose trying a rebuild.Your thoughts on difficulty to rebuild.Thank You.
@@williampalladino3663 The TBs themselves are super easy to rebuild. Just a gasket and a few seals. It’s very self explanatory once you open it up. Make sure you clean the inlet screens on the injectors while it’s apart.
Thanks for the video. Do I knock out the aluminum/metal housing located at the base of the injector or the black rubber smaller plug that's located in the aluminum/metal housing enclosure extending out of the fuel injector?
What are you talking about?
@@Joesmusclecargarage At the base of the regulator, there is a knockout plug. In the center of the knockout plug is a small circular rubber cover of some sort... My question is, do I remove the rubber cover, or do I remove the metal knockout? I can send a photo if you like.
@@daaframcampbell2463 You need to remove the metal knockout plug.
Joe on my injector head (1984 Corvette, L83), after removing the metal knockout plug I noticed a small vertical slit on the side of the housing unit which I’m able to visually see the regulator spring. The spring sits on top of the nut that is used to adjust the fuel pressure, however, a part of it extends slightly outside the slit in the housing unit. I’m unable to turn/adjust the regulator. Should I disassemble the injector head and try to set it so that it stays inside the unit?
To adjust the FPR correctly, you need to either buy or make a tool to turn the adjustment screw while the engine is running and while you have a fuel pressure gauge between the two throttle bodies, as mentioned in the video. The screw is very sensitive, and it doesn’t take much to make a big change.
What size are those fuel line nuts
The factory nuts are 11/16, and the ones on the aftermarket gauge I made are 5/8.
Whats the thread pitch of those inline nuts? Ive been trying to find a hard line, but i dont think they are sae threads? Or im missing something?
It’s just a standard 3/8” metal fuel line with inverted flare fittings.
Oh ok, so its the fitting that goes in to the throttle body that its a metric size? Because ive looking for a line for my throttle body and i can't find it, i had to watch your video again and i think i see a fitting that the line fits in to? Sorry im trying to get a fuel gauge on my Trans am when i replace all the intake gaskets, since my car now is falling on its face when i accelerate. Im trying to buy all the stuff before i start taking it apart. Im really happy your making this videos, especially the part when u say that people will rather put a carb instead of figuring out how to make them run good. I like to see the cfi run good, especially when ive heard that they tried to do it like the 302 crossram that camaros used in the 60s to race them and it had 2 carburetors. And also its a piece of history that we dont see everyday
Where is the fuel pump pressure tested? Is that done with the engine running?
Engine running, at the crossover line between the TBs.
I have a '83 Trans am with Crossfire. The only real problem is cold starts require a lot of cranking. It will finally start to stumble and then fire and run normal. Plenty of pull and smooth running on the highway. Is there any reason to check the fuel pressure? Could it be bad gas? Plugs? Plugged fuel filter? New idle air valves 50 miles ago. Great site!
@blackTtop There’s always a reason to check fuel pressure on a CFI. They were set low (8-10) from the factory. They run like shit if they’re not up around 13-14.
Once it starts it runs great and has for years, but lately it's been hard to get started and I'm trying to understand why.@@Joesmusclecargarage
Then check the FP. Are you still running the factory CTS?
What size fittings did you use on that guage ?
It’s standard 3/8 steel line
Do you know if this will work on the 84 c4?
If the car still has CFI it will.
On my 84 corvette I put a 85 fuel pump and had the throttle bodies rebuilt and he adjusted it to about 14lbs.
So my question is do I need a fuel pressure regulator because the 85 pump put out more pressure then the 84 pump? Or just Leave it alone.
14psi is fine, but it is at the “safe” limit for the factory FPR. Any more than 14 and you should consider eliminating the factory FPR and running an external regulator.
@@Joesmusclecargarage great information 👍
How do I remove factory FPR
DCS sells machined aluminum plates that go in place of the FPR and accumulator. Most of their products are out of stock, and likely out of production though. You can easily fabricate some plates though.
Hey Joe, do you do any work on 82 Corvettes? I have several with less than 5k miles that I am trying to salvage from being stored since the 80’s. I could use any help and advice I can get. The one I am working with now has a very low idle and will not stay running. I’m not a mechanic. Any ideas after having replaced fuel (and brakes)?
I do. Are you in AZ?
@@Joesmusclecargarage Heck no, I'm in Indiana! =((((
Renegade intake/1.6 roller rockers/long tube headers/dual cherry bombs(no cats)/DUI coil+ Module\k&n filter=gas pressure???? 16 maybe?
What’s your question? If you’re asking what your fuel pressure should be, 16psi is unnecessary, and are on the edge of what the FPR diaphragm will hold. If all you have is the manifold, rockers, and exhaust, no more than 14psi is necessary.
Hey Joe, shot you and email and some texts to no avail. Hit me up whenever you're free just had a few questions I could use your expertise on. Thanks.