12a turbo carb
10-29-12, 06:36 AM
#1
12a turbo carb
Can anybody explain turbo carbs to me? Especially how to rebuild a Nikki for turbo. I have another Nikki laying aroundnthat needs to be rebuilt, and I figure hell might as well outfit it for turbo. I want to have a better understanding of turbo carbs first though. Thanks. Btw I searched it and couldn't find anything useful.
10-29-12, 08:05 AM
#2
Not my area of expert-ese, but I can give you some ideas to search under. Boost prepping a Nikki involves (among other things) rebuilding the carb with special gaskets to handle boost. I would believe that some amount of extra jetting would be needed as well. Decide if you are going draw through or blowthrough. Some carbs like the side draft webers can handle a certain amount of boost right out of the box with no boost prepping necessary. You are also gonna need a wideband and a proper exhaust manifold.
10-29-12, 12:40 PM
#3
I have the exhaust mani already. A wideband though? I wasn't aware these cars even had o2 sensors lol. Looks like I haven't done as much research as I thought. Ultimately I want to go side draft since I have a mani for it, but I figure since I have a spare nikki and top draft mani might as well make do for the mean time. hats easier to build between blow and draw?
10-29-12, 03:08 PM
#5
I'll reply in this thread instead of your other one so I can supplement some info. The first thing you should do is do a little research on turbo setups in general. You seemed a little vague on the key concepts in the other thread and I think having a good understanding of how the plumbing all works will make researching a such daunting project as a blowthrough setup much easier.
You should also read up on rebuilding the stock Nikki. It can be a complicated process if you haven't done it before, and adding in modifications for a turbo will greatly increase the chance of a tiny mistake that will grind your project to a halt. My advice would be to rebuild the carburetor back to stock spec while removing the emissions equipment. It's well covered on this forum so you shouldn't have much trouble getting that part done. Reinstall the carb on the car and make sure it's working well. Then take it back apart and begin boost prepping it. I think that's the best way of doing the whole project... build as much as you can while keeping the car N/A, test each new setup, verify the new parts are working, then move on to the next thing. Makes debugging much less of a headache.
Now, as to turboing the 12a. Blowthrough is more involved, but produces much more power and is safer than a drawthrough. You can't run an intercooler on a drawthrough setup, which severely limits the amount of boost you can safely run. However it's cheaper and a little simpler to build. Either way, plan to spend a ton of money, a ton of time wrenching, and a lot more time researching. There's a lot of little projects that need to be done ahead of the actual build. I'll make a simple list, for blowthrough since that's the route I'm going:
For FMIC:
Relocate Battery to interior
Cut or fab radiator supports
Relocate coolant overflow tank
Fabricate brackets for intercooler
Upgrade oil system:
Install FMOC if car is S3.*
Upgrade oil pressure regulator or modify stock one, shim front cover bypass
Drill and tap front cover for turbo drain or swap TII front cover.
Run feed line with restrictor to turbo
Upgrade fuel system/carb/intake:
Install high flow pump and upgrade all wiring
Install rising rate FPR and gauge
Consider running larger fuel lines
Relocate savings account to glove box
Boost prep carb and take a wild guess on jetting changes
Install carb hat and run all intercooler piping, including BOV
Seal up factory intake manifold or install an aftermarket one
Have an entire exhaust system built
Have a bung welded in the downpipe for 02 sensor
Install wideband 02 sensor and gauge
Squeeze a turbo somewhere between the engine and the strut tower
Lock distributor and set timing
Change spark plugs to hotter set (9's or higher)
Blow apex seals and find someone parting out a TII
*I've seen people run turbo setups with the S3 beehive oil cooler. It can be done. I just don't recommend it because that cooler sucks. The higher temps wreak havoc on the motor. It's best to upgrade both the oil cooler and the radiator.
You should also read up on rebuilding the stock Nikki. It can be a complicated process if you haven't done it before, and adding in modifications for a turbo will greatly increase the chance of a tiny mistake that will grind your project to a halt. My advice would be to rebuild the carburetor back to stock spec while removing the emissions equipment. It's well covered on this forum so you shouldn't have much trouble getting that part done. Reinstall the carb on the car and make sure it's working well. Then take it back apart and begin boost prepping it. I think that's the best way of doing the whole project... build as much as you can while keeping the car N/A, test each new setup, verify the new parts are working, then move on to the next thing. Makes debugging much less of a headache.
Now, as to turboing the 12a. Blowthrough is more involved, but produces much more power and is safer than a drawthrough. You can't run an intercooler on a drawthrough setup, which severely limits the amount of boost you can safely run. However it's cheaper and a little simpler to build. Either way, plan to spend a ton of money, a ton of time wrenching, and a lot more time researching. There's a lot of little projects that need to be done ahead of the actual build. I'll make a simple list, for blowthrough since that's the route I'm going:
For FMIC:
Relocate Battery to interior
Cut or fab radiator supports
Relocate coolant overflow tank
Fabricate brackets for intercooler
Upgrade oil system:
Install FMOC if car is S3.*
Upgrade oil pressure regulator or modify stock one, shim front cover bypass
Drill and tap front cover for turbo drain or swap TII front cover.
Run feed line with restrictor to turbo
Upgrade fuel system/carb/intake:
Install high flow pump and upgrade all wiring
Install rising rate FPR and gauge
Consider running larger fuel lines
Relocate savings account to glove box
Boost prep carb and take a wild guess on jetting changes
Install carb hat and run all intercooler piping, including BOV
Seal up factory intake manifold or install an aftermarket one
Have an entire exhaust system built
Have a bung welded in the downpipe for 02 sensor
Install wideband 02 sensor and gauge
Squeeze a turbo somewhere between the engine and the strut tower
Lock distributor and set timing
Change spark plugs to hotter set (9's or higher)
Blow apex seals and find someone parting out a TII
*I've seen people run turbo setups with the S3 beehive oil cooler. It can be done. I just don't recommend it because that cooler sucks. The higher temps wreak havoc on the motor. It's best to upgrade both the oil cooler and the radiator.
10-30-12, 04:58 AM
#7
I'll reply in this thread instead of your other one so I can supplement some info. The first thing you should do is do a little research on turbo setups in general. You seemed a little vague on the key concepts in the other thread and I think having a good understanding of how the plumbing all works will make researching a such daunting project as a blowthrough setup much easier.
You should also read up on rebuilding the stock Nikki. It can be a complicated process if you haven't done it before, and adding in modifications for a turbo will greatly increase the chance of a tiny mistake that will grind your project to a halt. My advice would be to rebuild the carburetor back to stock spec while removing the emissions equipment. It's well covered on this forum so you shouldn't have much trouble getting that part done. Reinstall the carb on the car and make sure it's working well. Then take it back apart and begin boost prepping it. I think that's the best way of doing the whole project... build as much as you can while keeping the car N/A, test each new setup, verify the new parts are working, then move on to the next thing. Makes debugging much less of a headache.
Now, as to turboing the 12a. Blowthrough is more involved, but produces much more power and is safer than a drawthrough. You can't run an intercooler on a drawthrough setup, which severely limits the amount of boost you can safely run. However it's cheaper and a little simpler to build. Either way, plan to spend a ton of money, a ton of time wrenching, and a lot more time researching. There's a lot of little projects that need to be done ahead of the actual build. I'll make a simple list, for blowthrough since that's the route I'm going:
For FMIC:
Relocate Battery to interior
Cut or fab radiator supports
Relocate coolant overflow tank
Fabricate brackets for intercooler
Upgrade oil system:
Install FMOC if car is S3.*
Upgrade oil pressure regulator or modify stock one, shim front cover bypass
Drill and tap front cover for turbo drain or swap TII front cover.
Run feed line with restrictor to turbo
Upgrade fuel system/carb/intake:
Install high flow pump and upgrade all wiring
Install rising rate FPR and gauge
Consider running larger fuel lines
Relocate savings account to glove box
Boost prep carb and take a wild guess on jetting changes
Install carb hat and run all intercooler piping, including BOV
Seal up factory intake manifold or install an aftermarket one
Have an entire exhaust system built
Have a bung welded in the downpipe for 02 sensor
Install wideband 02 sensor and gauge
Squeeze a turbo somewhere between the engine and the strut tower
Lock distributor and set timing
Change spark plugs to hotter set (9's or higher)
Blow apex seals and find someone parting out a TII
*I've seen people run turbo setups with the S3 beehive oil cooler. It can be done. I just don't recommend it because that cooler sucks. The higher temps wreak havoc on the motor. It's best to upgrade both the oil cooler and the radiator.
You should also read up on rebuilding the stock Nikki. It can be a complicated process if you haven't done it before, and adding in modifications for a turbo will greatly increase the chance of a tiny mistake that will grind your project to a halt. My advice would be to rebuild the carburetor back to stock spec while removing the emissions equipment. It's well covered on this forum so you shouldn't have much trouble getting that part done. Reinstall the carb on the car and make sure it's working well. Then take it back apart and begin boost prepping it. I think that's the best way of doing the whole project... build as much as you can while keeping the car N/A, test each new setup, verify the new parts are working, then move on to the next thing. Makes debugging much less of a headache.
Now, as to turboing the 12a. Blowthrough is more involved, but produces much more power and is safer than a drawthrough. You can't run an intercooler on a drawthrough setup, which severely limits the amount of boost you can safely run. However it's cheaper and a little simpler to build. Either way, plan to spend a ton of money, a ton of time wrenching, and a lot more time researching. There's a lot of little projects that need to be done ahead of the actual build. I'll make a simple list, for blowthrough since that's the route I'm going:
For FMIC:
Relocate Battery to interior
Cut or fab radiator supports
Relocate coolant overflow tank
Fabricate brackets for intercooler
Upgrade oil system:
Install FMOC if car is S3.*
Upgrade oil pressure regulator or modify stock one, shim front cover bypass
Drill and tap front cover for turbo drain or swap TII front cover.
Run feed line with restrictor to turbo
Upgrade fuel system/carb/intake:
Install high flow pump and upgrade all wiring
Install rising rate FPR and gauge
Consider running larger fuel lines
Relocate savings account to glove box
Boost prep carb and take a wild guess on jetting changes
Install carb hat and run all intercooler piping, including BOV
Seal up factory intake manifold or install an aftermarket one
Have an entire exhaust system built
Have a bung welded in the downpipe for 02 sensor
Install wideband 02 sensor and gauge
Squeeze a turbo somewhere between the engine and the strut tower
Lock distributor and set timing
Change spark plugs to hotter set (9's or higher)
Blow apex seals and find someone parting out a TII
*I've seen people run turbo setups with the S3 beehive oil cooler. It can be done. I just don't recommend it because that cooler sucks. The higher temps wreak havoc on the motor. It's best to upgrade both the oil cooler and the radiator.
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10-30-12, 08:08 AM
#8
Lock the distributor means you pull it apart and weld the mech advance weights full advanced. This allows you set your timing and have it stay where you set it. Depending on what year engine you have, a gsl-se oil pump is probably the same, i know on my 83 engine they were the same anyway. No point in running a FMOC and a beehive. Throw the beehive in the trash where it belongs, it will clean up your bay a lot too. You need a rising rate fuel pressure regulator, not just a normal fuel pressure regulator. Say for instance a nikki carb needs 3psi of fuel pressure to work, that is all it needs, turbo or no turbo. But for every one psi of boost pressure, you have to increase the fuel pressure one psi or the boost pressure will prevent fuel getting to the carb. 3psi fuel pressure and 3psi boost = no fuel pressure lol The RRFPR's are boost referenced to increase 1:1. Don't run a top mount IC with out a hood scoop like the T2 has. I have no idea how you'd even really get one to work with a nikki anyway. FMIC's are better 
10-30-12, 11:27 AM
#9
I'd say just run a boost referenced FPR, not a rising rate FPR. There is a difference.
THEWITCHKING, what year is your engine? All true 83-85 12As had the correct oil pump. Don't buy into what RB says. All 12As that originally came stock with a beehive have the high volume oil pump. Take it out, measure the thickness (the little round gear/rotor thing). Is it 17mm or 12mm or the rare 74-75 15mm? If you do have a 12mm one from a 76-82, trash it and get a 17mm pump. Also look at your thrust assembly. It will be worn if it's an 82 or older due to lack of oil volume, or if it spent most of its life with a street strip pressure plate where the owner always pressed in the clutch at start up (it's not necessary in a 1st gen). Starting dry with that much mechanical pressure is a no-no. Don't ever push in the clutch to start these cars, unless they're already warmed up. Makes me think about FCs and all other cars that have a clutch safety switch.
THEWITCHKING, what year is your engine? All true 83-85 12As had the correct oil pump. Don't buy into what RB says. All 12As that originally came stock with a beehive have the high volume oil pump. Take it out, measure the thickness (the little round gear/rotor thing). Is it 17mm or 12mm or the rare 74-75 15mm? If you do have a 12mm one from a 76-82, trash it and get a 17mm pump. Also look at your thrust assembly. It will be worn if it's an 82 or older due to lack of oil volume, or if it spent most of its life with a street strip pressure plate where the owner always pressed in the clutch at start up (it's not necessary in a 1st gen). Starting dry with that much mechanical pressure is a no-no. Don't ever push in the clutch to start these cars, unless they're already warmed up. Makes me think about FCs and all other cars that have a clutch safety switch.
10-30-12, 12:50 PM
#11
Fitting a top mount in a first gen with carb hat is going to be tricky. Were you planning on running a hood at all? I would just go front mount. The FB has a long snout so there's plenty of room up there. And take it from me, making a hood scoop for the stock hood is a lot more work than just modifying the radiator brackets and running a front mount.
Jeff, care to go into detail about the boost referenced/rising rate FPR's? I got an Aeromotive RRFPR based on advice from another forum member running a blowthrough. And I never thought about the clutch thing. I don't put the clutch in to start my first gen just out of laziness, but my current second gen has that blasted safety switch. My old TII didn't, or at least it didn't work anymore.
Jeff, care to go into detail about the boost referenced/rising rate FPR's? I got an Aeromotive RRFPR based on advice from another forum member running a blowthrough. And I never thought about the clutch thing. I don't put the clutch in to start my first gen just out of laziness, but my current second gen has that blasted safety switch. My old TII didn't, or at least it didn't work anymore.
10-30-12, 01:54 PM
#13
I used to not know the difference between rising rate and boost referenced. Then I learned boost referenced raises fuel pressure on a 1:1 scale with boost. This is what you want. You do not want a rising rate because it raises fuel pressure more than a 1:1 ratio. I guess some V8 guys running 30 pounds of boost use them.
Then I come to find out most people who recommend a rising rate either don't know what they're talking about, are misinformed/ignorant themselves, or just plain lazy or forget to use the right terminology. Not a good thing to do on a forum where others take advice that could blow their engines.
So from what I can tell, a rising rate fpr has no place on this forum or your engine.
Then I come to find out most people who recommend a rising rate either don't know what they're talking about, are misinformed/ignorant themselves, or just plain lazy or forget to use the right terminology. Not a good thing to do on a forum where others take advice that could blow their engines.
So from what I can tell, a rising rate fpr has no place on this forum or your engine.
10-30-12, 02:40 PM
#14
I used to not know the difference between rising rate and boost referenced. Then I learned boost referenced raises fuel pressure on a 1:1 scale with boost. This is what you want. You do not want a rising rate because it raises fuel pressure more than a 1:1 ratio. I guess some V8 guys running 30 pounds of boost use them.
Then I come to find out most people who recommend a rising rate either don't know what they're talking about, are misinformed/ignorant themselves, or just plain lazy or forget to use the right terminology. Not a good thing to do on a forum where others take advice that could blow their engines.
So from what I can tell, a rising rate fpr has no place on this forum or your engine.
Then I come to find out most people who recommend a rising rate either don't know what they're talking about, are misinformed/ignorant themselves, or just plain lazy or forget to use the right terminology. Not a good thing to do on a forum where others take advice that could blow their engines.
So from what I can tell, a rising rate fpr has no place on this forum or your engine.
It's a "bypass regulator"
10-30-12, 03:31 PM
#15
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I've always heard "rising rate" used to describe any regulator that raises the fuel pressure under boost or low vacuum, whether rate is 1:1 or higher. As opposed to a static regulator that keeps pressure at a set amount. So I'll agree to disagree on that one. Anyway, here's the unit I have: Aeromotive*|*13301 - Universal Bypass Regulator
It's a "bypass regulator"
It's a "bypass regulator"
A real rising-rate regulator, by contrast, does vary the fuel differential pressure. They don't work well on carbed setups, and are usually used on EFI setups with non-tunable ECUs as a sort of crude hack to richen them up under boost. The reason you often hear normal boost-referenced FPRs described as "rising-rate" is because people are lazy/ignorant, as Jeff said.
A "bypass" regulator is as opposed to a "deadhead" style regulator. A deadhead regulator uses an adjustable restrictor on the supply side to change fuel pressure, and no return. A bypass regulator uses a fuel return with the restrictor in the return side. You could have a boost-referenced deadhead regulator as well.
Also, as a side note, in a blow-through carb setup, the FPR is not referenced to manifold pressure, but the pressure at the carb inlet, so it is not affected by manifold vacuum.
10-30-12, 03:36 PM
#17
FPR mallory 4309 is what I have and will be using with my set up. worked great has a 1-1 rate. Only problem I ran into is you might have to upgrade the return line. The stock return is too small and wouldnt let the fuel pressure go low enough to let teh carb run right.
10-30-12, 04:20 PM
#18
Lock the distributor means you pull it apart and weld the mech advance weights full advanced. This allows you set your timing and have it stay where you set it. Depending on what year engine you have, a gsl-se oil pump is probably the same, i know on my 83 engine they were the same anyway. No point in running a FMOC and a beehive. Throw the beehive in the trash where it belongs, it will clean up your bay a lot too. You need a rising rate fuel pressure regulator, not just a normal fuel pressure regulator. Say for instance a nikki carb needs 3psi of fuel pressure to work, that is all it needs, turbo or no turbo. But for every one psi of boost pressure, you have to increase the fuel pressure one psi or the boost pressure will prevent fuel getting to the carb. 3psi fuel pressure and 3psi boost = no fuel pressure lol The RRFPR's are boost referenced to increase 1:1. Don't run a top mount IC with out a hood scoop like the T2 has. I have no idea how you'd even really get one to work with a nikki anyway. FMIC's are better
10-30-12, 04:29 PM
#19
I'd say just run a boost referenced FPR, not a rising rate FPR. There is a difference.
THEWITCHKING, what year is your engine? All true 83-85 12As had the correct oil pump. Don't buy into what RB says. All 12As that originally came stock with a beehive have the high volume oil pump. Take it out, measure the thickness (the little round gear/rotor thing). Is it 17mm or 12mm or the rare 74-75 15mm? If you do have a 12mm one from a 76-82, trash it and get a 17mm pump. Also look at your thrust assembly. It will be worn if it's an 82 or older due to lack of oil volume, or if it spent most of its life with a street strip pressure plate where the owner always pressed in the clutch at start up (it's not necessary in a 1st gen). Starting dry with that much mechanical pressure is a no-no. Don't ever push in the clutch to start these cars, unless they're already warmed up. Makes me think about FCs and all other cars that have a clutch safety switch.
THEWITCHKING, what year is your engine? All true 83-85 12As had the correct oil pump. Don't buy into what RB says. All 12As that originally came stock with a beehive have the high volume oil pump. Take it out, measure the thickness (the little round gear/rotor thing). Is it 17mm or 12mm or the rare 74-75 15mm? If you do have a 12mm one from a 76-82, trash it and get a 17mm pump. Also look at your thrust assembly. It will be worn if it's an 82 or older due to lack of oil volume, or if it spent most of its life with a street strip pressure plate where the owner always pressed in the clutch at start up (it's not necessary in a 1st gen). Starting dry with that much mechanical pressure is a no-no. Don't ever push in the clutch to start these cars, unless they're already warmed up. Makes me think about FCs and all other cars that have a clutch safety switch.
Boost referenced it is then. What's weird to me is that my nismo afpr I was running on my rb20det was a rising rate. You think they woulda known better. Either way I just read up on it, and boost referenced is what I'm getting.
My motor is an 84 though. Same as the chassis. Don't know what a thrust assembly, but I've never really clutch started it more out of laziness than anything. Never needed to on any of my cars. Not my integra, 240, Saab 900, Volvo etc.. Is that weird? I've had friends tell me it's not supposed to start without the clutch depressed but that mechanically doesn't make sense to me. I haven't cared too much to put enough thought into it obviously lol. Anyway back on track I'll have to look up how to remove the oil pump since I have o idea where it would be or what to look for.
[edit] Oh and btw, is it necessary to be running two fprs? Or can I just buy one boost referenced and call it good?
Last edited by THEWITCHKING; 10-30-12 at 04:32 PM.
10-30-12, 04:36 PM
#20
Fitting a top mount in a first gen with carb hat is going to be tricky. Were you planning on running a hood at all? I would just go front mount. The FB has a long snout so there's plenty of room up there. And take it from me, making a hood scoop for the stock hood is a lot more work than just modifying the radiator brackets and running a front mount.
Jeff, care to go into detail about the boost referenced/rising rate FPR's? I got an Aeromotive RRFPR based on advice from another forum member running a blowthrough. And I never thought about the clutch thing. I don't put the clutch in to start my first gen just out of laziness, but my current second gen has that blasted safety switch. My old TII didn't, or at least it didn't work anymore.
Jeff, care to go into detail about the boost referenced/rising rate FPR's? I got an Aeromotive RRFPR based on advice from another forum member running a blowthrough. And I never thought about the clutch thing. I don't put the clutch in to start my first gen just out of laziness, but my current second gen has that blasted safety switch. My old TII didn't, or at least it didn't work anymore.
10-30-12, 09:43 PM
#23
Jeff is technically correct on this one. It isn't appropriate to call what you have a "rising-rate" pressure regulator, because the fuel differential pressure is static. Its output will always be equal to the reference pressure plus the base pressure. The only difference between that and a non-boost-referenced type is where the reference pressure is taken. The fuel absolute pressure does vary, yes, but that's true of ALL fuel pressure regulators, and the term "rising-rate" would lose its meaning if it were applied to all types of regulators.
A real rising-rate regulator, by contrast, does vary the fuel differential pressure. They don't work well on carbed setups, and are usually used on EFI setups with non-tunable ECUs as a sort of crude hack to richen them up under boost. The reason you often hear normal boost-referenced FPRs described as "rising-rate" is because people are lazy/ignorant, as Jeff said.
A "bypass" regulator is as opposed to a "deadhead" style regulator. A deadhead regulator uses an adjustable restrictor on the supply side to change fuel pressure, and no return. A bypass regulator uses a fuel return with the restrictor in the return side. You could have a boost-referenced deadhead regulator as well.
Also, as a side note, in a blow-through carb setup, the FPR is not referenced to manifold pressure, but the pressure at the carb inlet, so it is not affected by manifold vacuum.
A real rising-rate regulator, by contrast, does vary the fuel differential pressure. They don't work well on carbed setups, and are usually used on EFI setups with non-tunable ECUs as a sort of crude hack to richen them up under boost. The reason you often hear normal boost-referenced FPRs described as "rising-rate" is because people are lazy/ignorant, as Jeff said.
A "bypass" regulator is as opposed to a "deadhead" style regulator. A deadhead regulator uses an adjustable restrictor on the supply side to change fuel pressure, and no return. A bypass regulator uses a fuel return with the restrictor in the return side. You could have a boost-referenced deadhead regulator as well.
Also, as a side note, in a blow-through carb setup, the FPR is not referenced to manifold pressure, but the pressure at the carb inlet, so it is not affected by manifold vacuum.
You only need one regulator, thewitchking.
Seanrot, what size return line did you end up using?
10-31-12, 01:42 AM
#24
I was going to use my stock send line (which is 8mm or basically 5/16") as a return, but now I'm thinking it may not be adequate, as I may need to use a boost prepped Nikki (and they like 2.5 to 3 psi). So I'll probably just swap in two 3/8" hardlines and call it good. As for the return that goes into the tank, I'll Tee the 3/8" return line and adapt one side down to 5/16" and the other down to 1/4". This should work because it will priovide two ways into the tank. Plus I've got an independant dedicated 3/8" send line plumbed at the bottom already.
I've got the Mallory 4309. Haven't used it yet. These seem to bottom out at 3psi, right? I hope that'll do.
The Nikki should be deadheaded too, right? I've heard of someone using the Nikki's return fitting (1/4") and a different fpr, like a bypass type or something. That sounds like a bad idea to me. I'd rather deadhead it like any other carb that doesn't have a return, like Holley, Weber, Edlebrock etc.
I've got the Mallory 4309. Haven't used it yet. These seem to bottom out at 3psi, right? I hope that'll do.
The Nikki should be deadheaded too, right? I've heard of someone using the Nikki's return fitting (1/4") and a different fpr, like a bypass type or something. That sounds like a bad idea to me. I'd rather deadhead it like any other carb that doesn't have a return, like Holley, Weber, Edlebrock etc.
10-31-12, 02:11 AM
#25
Aeromotive recommends a 1/2" return line for 5-10ft at 3-20 PSI. That seemed a bit overkill for me, I figured 3/8" would cut it. I've been trying to figure the fuel plumbing conundrum today as this will be my next step in the project after I finish mounting the intercooler. I'm thinking your idea of splitting the 3/8 return at the tank should work as long as the T fitting itself isn't a bottleneck. You're still working with the same bandwidth, so to speak - just splitting it into two channels.
I'm thinking deadhead the Nikki. I read on Sterling's site that the Nikki can be deadheaded successfully. Removing the banjo bolt and fitting on the return side and installing a normal bolt and washer with some thread sealant should work, right?
I'm going to try this out before I put the turbo on the car. The regulator I have can be adjusted down to 3 PSI, which is what I have the current Holley regulator set on. I can just leave the reference open to the atmosphere for now. My goal is to test out every piece of the puzzle I can before I actually add boost to make the final debug easier.
I'm thinking deadhead the Nikki. I read on Sterling's site that the Nikki can be deadheaded successfully. Removing the banjo bolt and fitting on the return side and installing a normal bolt and washer with some thread sealant should work, right?
I'm going to try this out before I put the turbo on the car. The regulator I have can be adjusted down to 3 PSI, which is what I have the current Holley regulator set on. I can just leave the reference open to the atmosphere for now. My goal is to test out every piece of the puzzle I can before I actually add boost to make the final debug easier.