b-body-bob
Well-known member
FWIW, no progress to note, too many other things going on here recently. I did manage to realize that is a volt meter and not an amp gauge under the dash before I burned the car to the ground.
My 71 Duster work in progress
- Thread starter b-body-bob
- Start date
b-body-bob
Well-known member
I planned to back the car out, make a bunch of noise, then pull it back in a couple of times to settle the suspension and then check the alignment, but it wouldn't start. I broke out the remote starter switch, and could see there was zero fuel pressure according to the fuel gauge at the carb. I know there's gasoline in the car but shook and listened for the slosh to be sure. After removing the pump I'm sure it's not the push rod too. So now I'm trying to figure out just how stupid I want to get on the replacement, price wise.
I'm kind of leery of buying anything but a straight replacement for the one that was on there, because of the elephant ears maybe being in the way of a larger pump.
While I had the fuel line off I thought I'd see about replacing the dual line at the carb, since its a fake AN setup with hidden hose clamps. Of course the front nut was stuck in the carb fitting, and it all rounded off so I ended up taking the hose out then bending as needed to take the fitting and all out. So I should probably order another fitting and will need a new dual line too.
I went ahead and took the front bowl off and noticed the carb has 80 primary jetting. I haven't broke the carb book out to refresh my memory, but that seems way too big for a street car. IIRC my road runner has 76 or so in the front and it ran 7.20s in the eighth. In fact I may just swipe the carb off that engine since it's going to be a 6 pack if/when it ever runs again. Both the rr and the duster have 850 DPs on them but the rr carb has been tuned with 50cc pumps, etc.
I'm kind of leery of buying anything but a straight replacement for the one that was on there, because of the elephant ears maybe being in the way of a larger pump.
While I had the fuel line off I thought I'd see about replacing the dual line at the carb, since its a fake AN setup with hidden hose clamps. Of course the front nut was stuck in the carb fitting, and it all rounded off so I ended up taking the hose out then bending as needed to take the fitting and all out. So I should probably order another fitting and will need a new dual line too.
I went ahead and took the front bowl off and noticed the carb has 80 primary jetting. I haven't broke the carb book out to refresh my memory, but that seems way too big for a street car. IIRC my road runner has 76 or so in the front and it ran 7.20s in the eighth. In fact I may just swipe the carb off that engine since it's going to be a 6 pack if/when it ever runs again. Both the rr and the duster have 850 DPs on them but the rr carb has been tuned with 50cc pumps, etc.
b-body-bob
Well-known member
Well, google tells me that the 850 comes stock with 80s primary and secondary so maybe I'm remembering wrong.
Dr.Jass
Pastor of Muppets
A big block with a bad fuel pump? Inconceivable! 
I say that only because Kevin has gone through about one every two years on his 440... I don't have any recommendations for a replacement; whichever he uses is clearly not very good but he's determined to stay OE-appearing.
First and foremost, check the obvious. It seems to me you were messing with the tank at one point; is everything connected and clamped from sender to carb? Did you check the fuel pump pushrod? There was a bad run of those several years ago and who knows what's in the engine you've got. The pushrod will wipe just like a lifter; it needs to be broken in just like lifters too. Take it out and have a peek at the camshaft end.
A lot of people forget that jetting isn't just a function of engine size, but the engine's draw through the particular carb being used. 72s might work great on a 600 but be too lean on an 800 on the same engine--a 600 has both a smaller throttle opening and a smaller venturi, which will more-easily pull fuel through the jets. Don't worry about jetting for the moment. It has exactly zero effect at idle or cruise on a Holley; it's not a concern until you're well into the throttle. You could put 96s in it all the way around and it would make no difference if you drove it like Grandmother would've. Similarly, don't listen to even Holley's advice for your power valve(s). 6.5 is a good starting point, and the best way to tune it is by driving the car, preferably with an A/F meter. Barring that you want smooth, hesitation-free operation in your transition from mid-throttle acceleration to WOT.
Worry about your timing first. Not knowing what cam you've got, I'd suggest starting around 12-14° base or 36° total (if you've got a dial-back light) and tweaking from there. Once that's set, and only after that, should you start worrying about idle mixture, jetting, and all the other joys a Holley brings.
I say that only because Kevin has gone through about one every two years on his 440... I don't have any recommendations for a replacement; whichever he uses is clearly not very good but he's determined to stay OE-appearing.First and foremost, check the obvious. It seems to me you were messing with the tank at one point; is everything connected and clamped from sender to carb? Did you check the fuel pump pushrod? There was a bad run of those several years ago and who knows what's in the engine you've got. The pushrod will wipe just like a lifter; it needs to be broken in just like lifters too. Take it out and have a peek at the camshaft end.
A lot of people forget that jetting isn't just a function of engine size, but the engine's draw through the particular carb being used. 72s might work great on a 600 but be too lean on an 800 on the same engine--a 600 has both a smaller throttle opening and a smaller venturi, which will more-easily pull fuel through the jets. Don't worry about jetting for the moment. It has exactly zero effect at idle or cruise on a Holley; it's not a concern until you're well into the throttle. You could put 96s in it all the way around and it would make no difference if you drove it like Grandmother would've. Similarly, don't listen to even Holley's advice for your power valve(s). 6.5 is a good starting point, and the best way to tune it is by driving the car, preferably with an A/F meter. Barring that you want smooth, hesitation-free operation in your transition from mid-throttle acceleration to WOT.
Worry about your timing first. Not knowing what cam you've got, I'd suggest starting around 12-14° base or 36° total (if you've got a dial-back light) and tweaking from there. Once that's set, and only after that, should you start worrying about idle mixture, jetting, and all the other joys a Holley brings.
b-body-bob
Well-known member
Thanks. I need a refresher on carb specifics. I got a grip on the theory a while back.
There's nothing wrong with the car. It is new from the gas cap to the fuel pump and from the fuel pump to the inlet of the dual line. The only thing it could be other than the pump is the new sending unit, and it's easier to change the fuel pump that it is to take all that apart and find nothing's wrong.
The pump I've settled on is a Carter M4845 specifically noted as a muscle car part and with 3/8 barb inlet and corresponding outlet for the hard line I'll make for it.
The car's tuned timed etc good enough given that I still don't have the title for it. I'm holding off on putting the fenders on it until after john law sees it. John law won't come look at it until I go to the copshop to submit their filthy lucre. I won't go to the copshop until after I get a new inspection sticker on my car (we have 3 cars, none have a valid sticker). I have an appt to get that and my 6 months late annual service on the VW the 2nd. I will probably go to the copshop that same day since I'll be off work.
I was hoping to align it before the fenders go on because that will save me from having to reach in through the wheel opening to make adjustments.
Anyway, parts will be here Wednesday. I'll be working on electric/lights out in the yard most of the day today.
There's nothing wrong with the car. It is new from the gas cap to the fuel pump and from the fuel pump to the inlet of the dual line. The only thing it could be other than the pump is the new sending unit, and it's easier to change the fuel pump that it is to take all that apart and find nothing's wrong.
The pump I've settled on is a Carter M4845 specifically noted as a muscle car part and with 3/8 barb inlet and corresponding outlet for the hard line I'll make for it.
The car's tuned timed etc good enough given that I still don't have the title for it. I'm holding off on putting the fenders on it until after john law sees it. John law won't come look at it until I go to the copshop to submit their filthy lucre. I won't go to the copshop until after I get a new inspection sticker on my car (we have 3 cars, none have a valid sticker). I have an appt to get that and my 6 months late annual service on the VW the 2nd. I will probably go to the copshop that same day since I'll be off work.
I was hoping to align it before the fenders go on because that will save me from having to reach in through the wheel opening to make adjustments.
Anyway, parts will be here Wednesday. I'll be working on electric/lights out in the yard most of the day today.
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Dr.Jass
Pastor of Muppets
...or a hose clamp you forgot to tighten. I'm not trying to be an ass; sometimes it's really that simple. I once spent a whole bunch of money replacing electrical parts only to find that a wire I'd cut wasn't what I thought it was. Whoops.
The pump pushrod is also a known common issue. While you've got your pump out, it's worth inspecting since it slides right out. Hell, half the time it falls out while removing the pump. It won't if the end is wiped, though.
I just hate seeing money spent on unnecessary or wrong parts.
b-body-bob
Well-known member
It ran before so it's not anything simple like a hose clamp. All the clamps are tight anyway. Like everything else on this car, the fuel pump is old and needed replaced even if it hadn't failed. The lines had gas in them but the pump just wasn't making pressure
I didn't take the pushrod out but slid it up and felt the end of it and it's not mushroomed or anything like that. You're right no big deal to take it out.
The aggravating part of it all is that Summit free shipping used to be next day here since they shipped out of Akron and that's only about 3 hours from here. This order is shipping out of TX, and I'll be lucky to get it when it's scheduled which is now another day later on Thursday.
The fuel pump is the cheap part of this anyway. The spark plugs cost twice as much.
I didn't take the pushrod out but slid it up and felt the end of it and it's not mushroomed or anything like that. You're right no big deal to take it out.
The aggravating part of it all is that Summit free shipping used to be next day here since they shipped out of Akron and that's only about 3 hours from here. This order is shipping out of TX, and I'll be lucky to get it when it's scheduled which is now another day later on Thursday.
The fuel pump is the cheap part of this anyway. The spark plugs cost twice as much.
Dr.Jass
Pastor of Muppets
When they fail, they fail on the camshaft end. I've yet to see one wipe at the pump end.
On the bright side, Texans now get their shit the next day.
Seriously, I felt your pain back when I still dealt with Summit. They're warehouse diversification efforts turned a lot of 2nd-day stuff into week-or-more stuff.I can't think of any spark plug costing more than maybe $3 each that I'd put into a vintage Mopar engine, including my own more-expensive-by-the-day W2 project. That thing idles so rich some people want it to pay taxes and smokes like the Tirpitz's defensive screen, but it has yet to misfire once on the $2.39 RN12YCs I installed before first start. Please reassure me you didn't buy Accel.
b-body-bob
Well-known member
I still need to take the pushrod out.
I got the parts today, didn't read the fine print, and the stupid fuel pump has an NPS fitting on the outlet so I'm not sure what to do. I guess it's either find an adapter or return the stupid thing, either way it costs more money.
I don't know what the hell is up with a factory pump with a 3/8" inlet and a 1/8" NPSF outlet but it's right there in the specs and I didn't pick up on it. Apparently that's a typical size for a transmission fitting, and NPS is not the same thing as NPT. The internet says they've used a 1/8" NPT X 1/2-20 inverted flare for 5/16" hard line adapter. Seems dumb to deliver fuel at 3/8 then restrict it with an adapter and a 5/16 line.
I bought Champion RJ12YC $6.99 each, they don't seem to be the same thing as an RN12YC. RJ is 3/8" reach, RN is 3/4".
Now I need to go see what is in it, they were Bosch brand IIRC.
In the future I'll should stick with buying local, even if I can't get exactly what I want so at least I can return it easily.
I wonder what happens when you qualified for the free shipping, then returned stuff until you no longer qualify for it? I know I'll end up paying return shipping but could they hit me for the initial shipping too? More research is needed.
I got the parts today, didn't read the fine print, and the stupid fuel pump has an NPS fitting on the outlet so I'm not sure what to do. I guess it's either find an adapter or return the stupid thing, either way it costs more money.
I don't know what the hell is up with a factory pump with a 3/8" inlet and a 1/8" NPSF outlet but it's right there in the specs and I didn't pick up on it. Apparently that's a typical size for a transmission fitting, and NPS is not the same thing as NPT. The internet says they've used a 1/8" NPT X 1/2-20 inverted flare for 5/16" hard line adapter. Seems dumb to deliver fuel at 3/8 then restrict it with an adapter and a 5/16 line.
I bought Champion RJ12YC $6.99 each, they don't seem to be the same thing as an RN12YC. RJ is 3/8" reach, RN is 3/4".
Now I need to go see what is in it, they were Bosch brand IIRC.
In the future I'll should stick with buying local, even if I can't get exactly what I want so at least I can return it easily.
I wonder what happens when you qualified for the free shipping, then returned stuff until you no longer qualify for it? I know I'll end up paying return shipping but could they hit me for the initial shipping too? More research is needed.
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Dr.Jass
Pastor of Muppets
What kind of fuel pump did you get?! NPS just seems a stupid idea... I've worked in auto parts most of my life and not one place I've worked had NPS fittings or components on-hand, other than potentially some transmission fittings--all late-model stuff, and the exception rather than the rule v. NPT. The whole concept of an NPS hose barb seems a bit daft, really. Why they wouldn't just use 1/4"NPT is beyond me... unless, of course, they want to sell you a 1/8"NPS x -6AN adapter, and the hose/fittings necessary to route that to the carb. Expensive nonsense, that stuff.
As far as the 3/8" to 1/8"NPT restriction, I think it's mostly to ease flow on the draw side of the pump. Pumps love to push but hate pulling. The 3/8" line saves stress on the diaphragm. I did everything possible with my electric pump to ease the draw restrictions. 5/16" should be enough to keep your engine fed, since I assume you have float bowls to empty before actual hard flow becomes an issue. 1/8"NPT x 3/8" hose barbs exist, too, but massaging the inside a bit to remove restriction is a good idea (that's true of the 5/16" part, honestly).
$7 per plug is highway robbery. That's more than twice my "any jackass off the street" price here. Next time you need plugs, hit me up. I could've saved you about $25 just on the plugs, including USPS Priority Flat Rate shipping.
As far as the 3/8" to 1/8"NPT restriction, I think it's mostly to ease flow on the draw side of the pump. Pumps love to push but hate pulling. The 3/8" line saves stress on the diaphragm. I did everything possible with my electric pump to ease the draw restrictions. 5/16" should be enough to keep your engine fed, since I assume you have float bowls to empty before actual hard flow becomes an issue. 1/8"NPT x 3/8" hose barbs exist, too, but massaging the inside a bit to remove restriction is a good idea (that's true of the 5/16" part, honestly).
$7 per plug is highway robbery. That's more than twice my "any jackass off the street" price here. Next time you need plugs, hit me up. I could've saved you about $25 just on the plugs, including USPS Priority Flat Rate shipping.
b-body-bob
Well-known member
It's a Carter 4845 pump. The internet says an NPT adapter is needed for that pump. The mfr data at Summit and RockAuto says it's NPS.
I went ahead and put the overpriced plugs in last night Still have one wire that I couldn't get all the way on. It's tight on the passenger side.
I took the pushrod out and it's the same on both ends, no damage.
I went ahead and put the overpriced plugs in last night Still have one wire that I couldn't get all the way on. It's tight on the passenger side.
I took the pushrod out and it's the same on both ends, no damage.
b-body-bob
Well-known member
from What is the difference between NPT and NPS thread? | U.S. Plastic
So if that's really NPS threads I will not be able to use an NPT adapter and will be lucky to find the right one. This is pretty screwed up IMO.
So if that's really NPS threads I will not be able to use an NPT adapter and will be lucky to find the right one. This is pretty screwed up IMO.
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b-body-bob
Well-known member
Maybe I do, will look. But note in the website I quoted it says they will NPT and NPS will thread together but will leak if they don't match.
I'll definitely know if NPT will work before this weekend's over.
Dr.Jass
Pastor of Muppets
Looking at the picture of the pump, it has to be NPT. There's literally not enough surface area on that fitting for a sealing washer. The washer is larger than the hex on the adapter fitting and would be considerably larger than the one shown on the pump. As far as the error, I think it's a typo on Carter's part. Their site indeed lists it as NPS, but I can't see that being possible.
I think the M6935 would be a better pump for the application, but the M4845 is the one listed for the muscle-era stuff. The latter doesn't have a particularly stellar reputation, though.
I think the M6935 would be a better pump for the application, but the M4845 is the one listed for the muscle-era stuff. The latter doesn't have a particularly stellar reputation, though.
b-body-bob
Well-known member
I found an NPT fitting that threads into it.
Another thing I found is that the F in NPSF is for dryseal, some say it means fuel, but it does mean don't use anything on it like pipe dope or teflon tape.
I'm going to get an NPT fitting and install it, if it doesn't leak, I win.
If it lasts a few years it will outlast that engine in that car anyway. Unless I sell it.
Another thing I found is that the F in NPSF is for dryseal, some say it means fuel, but it does mean don't use anything on it like pipe dope or teflon tape.
I'm going to get an NPT fitting and install it, if it doesn't leak, I win.
If it lasts a few years it will outlast that engine in that car anyway. Unless I sell it.
Dr.Jass
Pastor of Muppets
There are both NPTF and NPSF threads, and yes--the F stands for "Fuel" indicating that for which the Dryseal design was intended. Regardless, it's quite unlikely Carter suddenly re-engineered a 55-year-old pump design to suddenly include an updated thread. It's NPT; I'd bet someone else's next paycheck on it.
These companies pay college students, monkeys, and layabouts to do data entry, usually from home in their spare time. Most of them have never set foot in a parts store nor know anything of thread designations, fuel systems, cars, or common sense. Carter's paper catalog lists not one single connection designation for any of the hundreds of fuel pumps they sell for "OE" applications.
I'm not telling you it's junk; yours might work perfectly. I'm just passing along known areas of concern to keep in mind when diagnosing later. If that's the pump my buddy's been using on his '71 Charger, he's gone through at least five--maybe seven--in the last decade. That car rarely if ever sees 1,000 miles per year, partially because he's afraid of the pump stranding him yet again.
At a guess, I would bet that pump number has somehow developed a defect (worn tooling, inferior materials, effect of today's substandard fuels?) in the bypass that allows the pressure to moonshot, destroying a diaphragm that was originally designed to provide only 6PSI. It's also possible, if not likely, that similar issues exist with the M6935.
These companies pay college students, monkeys, and layabouts to do data entry, usually from home in their spare time. Most of them have never set foot in a parts store nor know anything of thread designations, fuel systems, cars, or common sense. Carter's paper catalog lists not one single connection designation for any of the hundreds of fuel pumps they sell for "OE" applications.
The above comment is based on a couple of reports I found whilst trying to find info on a "Carter 4845" pump without the "M" designation. One was its 1-3 month longevity due to failed diaphragms, but the other was fuel delivery in the 15-19PSI (!) range. If you have a mysterious "insanely rich" issue with your car, check the fuel pressure or look for fuel dripping out of the boosters, particularly at cruise RPM. A Holley will only withstand about 7-8PSI before the pump pushes fuel past the needle and seat; CarterBrocks and Rochesters aren't happy above 5-6PSI.
I'm not telling you it's junk; yours might work perfectly. I'm just passing along known areas of concern to keep in mind when diagnosing later. If that's the pump my buddy's been using on his '71 Charger, he's gone through at least five--maybe seven--in the last decade. That car rarely if ever sees 1,000 miles per year, partially because he's afraid of the pump stranding him yet again.
At a guess, I would bet that pump number has somehow developed a defect (worn tooling, inferior materials, effect of today's substandard fuels?) in the bypass that allows the pressure to moonshot, destroying a diaphragm that was originally designed to provide only 6PSI. It's also possible, if not likely, that similar issues exist with the M6935.
b-body-bob
Well-known member
I bought the adapter last night put thread sealant on per the directions and threaded it in. Had some trouble getting the pump in the hole and flat against the block due to the elephant ear being right on top of it so I walked away. It looks to be dimensionally the same as the one I took off so it's going in the hole today whether it likes it or not.
I read about the pressure problems after I had the pump in hand. The dual line to the carb has a gauge at the inlet so if it goes insane I will see it.
I'd bet that the only difference between all the BB pumps from Carter is the orientation and type of inlet-outlet connections.
The longer this goes on the more I wish I would've bought an electric pump and all the other parts to make it work.
I read about the pressure problems after I had the pump in hand. The dual line to the carb has a gauge at the inlet so if it goes insane I will see it.
I'd bet that the only difference between all the BB pumps from Carter is the orientation and type of inlet-outlet connections.
The longer this goes on the more I wish I would've bought an electric pump and all the other parts to make it work.
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Dr.Jass
Pastor of Muppets
I'd agree with that statement, hence the last sentence of my previous post. I didn't do any research into the M6935 to find out if there were similar complaints about it. The Airtex part number for that application is the same number as the Carter without the M, which leads me to believe I know where they're sourcing it (and Airtex pumps in general have a dismal reputation). I can't speak for the US MotorWorks unit. We used to sell USMW at work, but they've largely disappeared from the warehouse shelves. Whether that's due to warranty issues I don't know.
Having seen what ethanol does to the insides of carburetors, I'd expect it has similar effects on fuel pumps. Ethanol-resistant carb kits can be bought; mechanical fuel pumps not so much. I'd suggest only ethanol-free fuel if you can source it easily, just to take that out of the equation. Stretch uses it in his Charger and has seen myriad benefits, including better starting and improved economy.
It would certainly save headaches if you ever decide to swap engines. I plan to do exactly that on the Valiant eventually, which is one of the reasons I used one. I'll just need to run one line from the frame-mounted regulator to the carburetor. Everything else is already plumbed and working.
At one point I intended my Challenger to be EFI, so I bought a Tanks, Inc. EFI tank and the corresponding sender for it. I've since decided to run the Six Pack setup, but I'm glad I've got that tank. An in-tank pump should be a ton quieter than the rather-noisy Carter electric on the Valiant--which is nowhere near as loud as a Holley red or blue. I don't mind the noise on the Valiant so much; it kind of works with the nature of the car. I'd rather not hear it on the Challenger, though. I haven't decided on a specific pump yet, but it will be an E85-capable EFI unit despite having no intent to use such fuel or pressures. The regulator will mount where the OE mechanical pump was and use a return line. Fingers crossed, it should be quiet, reliable, and easily sourced in the event of failure.
Now, go show that fuel pump who's boss. Call it bad names if necessary.
b-body-bob
Well-known member
It made noise, but man it turned out to be a charlie foxtrot.
First I had to grind more off the elephant ear to make room for it. It was more of a continuation of a job done in the past that stopped too soon. The old pump slapped right in, the new one wouldn't go flat against the block. I've got a hand-held belt sander with 60-grit belts that made short work of that.
Once I could put the pump where it needed to be, I noticed that the outlet fitting was pointed right at the mounting point for the elephant ear so there wasn't enough room to put the old hard line back. on. After another trip to the parts store for more adapters, I ended up with a 45 off the pump into a 3/8 barb and a rubber hose all the way to the carb. Yeah I don't much like it either. It was up against metal in a couple of places so I stuck a piece of corrugated wiring sheath or whatever the hell that stuff is called around it.
I didn't rebuild the carb but had to pull the front bowl because it leaked after I had it off to fix that rounded off inlet fitting. I swear that used gasket looked good but it wasn't. While I had it apart with the parts to do it I went ahead and stuck a new PV and pump diaphragm in it too.
The fittings, sealant, hose, and clamps from the parts store added up to about 2x what the pump cost, and I've got a couple of fittings that I didn't use. This is what happens when you buy a hillbillied-up Mopar.
Gina hopped in and revved the shit out of it for a while so I know there's no smoke, black blue or white, with it warmed up running in the garage, and there's no unburned fuel floating around in the air so that's good. Fuel pressure bounces between 6 and 8 with the car running.
I've still got to replace the nylon oil pressure hose with copper before it springs a leak
Also, from looking at my collection of jets, I think the A12 440 has 80s in the front and 86s in the back
FWIW I looked at those FI tanks when I replaced mine but thought it would be more trouble than it was worth. I might have been wrong. The A12 has a holley blue on it. You can only hear it until the car fires but OTOH you have a hard time hearing yourself think with that thing running.
First I had to grind more off the elephant ear to make room for it. It was more of a continuation of a job done in the past that stopped too soon. The old pump slapped right in, the new one wouldn't go flat against the block. I've got a hand-held belt sander with 60-grit belts that made short work of that.
Once I could put the pump where it needed to be, I noticed that the outlet fitting was pointed right at the mounting point for the elephant ear so there wasn't enough room to put the old hard line back. on. After another trip to the parts store for more adapters, I ended up with a 45 off the pump into a 3/8 barb and a rubber hose all the way to the carb. Yeah I don't much like it either. It was up against metal in a couple of places so I stuck a piece of corrugated wiring sheath or whatever the hell that stuff is called around it.
I didn't rebuild the carb but had to pull the front bowl because it leaked after I had it off to fix that rounded off inlet fitting. I swear that used gasket looked good but it wasn't. While I had it apart with the parts to do it I went ahead and stuck a new PV and pump diaphragm in it too.
The fittings, sealant, hose, and clamps from the parts store added up to about 2x what the pump cost, and I've got a couple of fittings that I didn't use. This is what happens when you buy a hillbillied-up Mopar.
Gina hopped in and revved the shit out of it for a while so I know there's no smoke, black blue or white, with it warmed up running in the garage, and there's no unburned fuel floating around in the air so that's good. Fuel pressure bounces between 6 and 8 with the car running.
I've still got to replace the nylon oil pressure hose with copper before it springs a leak
Also, from looking at my collection of jets, I think the A12 440 has 80s in the front and 86s in the back
FWIW I looked at those FI tanks when I replaced mine but thought it would be more trouble than it was worth. I might have been wrong. The A12 has a holley blue on it. You can only hear it until the car fires but OTOH you have a hard time hearing yourself think with that thing running.