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LTX and LSXPutting LT1s, LS1s, and their variants into Third Gens is becoming more popular. This board is for those who are doing and have done the swaps so they can discuss all of their technical aspects including repairs, swap info, and performance upgrades.
Is there nothing else required on the fuel tank side?
The 255 would be all of the pump that you will need for a NA 5.3. The 340 would be required if you are making over 600 HP, so the 400 is way too much pump unless you have power adders, and then you would not be using the filter/regulator with either pump. The Corvette filter/regulator is a dead head system and is fine for stock or mild upgrades, where high HP or power adders would require a bypass fuel system. As far as the fuel tank is concerned, it would depend on the pump module that you are using. The 4th gen. Camaro has a pressure regulator as part of the sump, whereas the Corvette did not, hence the filter/regulator. I hope this is helpful.
I figured more pump would be better rather than maxing out the 255 in the future when the upgrades come along in the future. Motor made 400rwhp NA. What's the c5 regulator good for, 500ish HP as well? And then ditch that and have to go with an inline fuel filter and a fuel pressure regulator?
3rd gen tank, can I leave the stock EVAP vent valve and stuff how it is?
What type of Fuel is being used?
Alcohol based Fuels will require significantly more Flow/ Volume than Gasoline.
You do not want to Max-Out the Fuel Injectors or the Fuel Pump(s)...
If affordable, always leave some extra head room with the Injectors and Pump(s).
Once you have determined what Pump will be used, obtain a Fuel Filter that can flow more than the Pump will produce.
You do not want a Fuel Filter that will end up restricting the Fuel Pump performance.
The Racetronix 340 pump has a different harness and fuel tank bulkhead with larger wires, relay, and connectors that carry more current. It's not just a larger pump, it's larger everything in the electrical circuit.
Testing by Lingenfelter has shown that the stock f body and C5 filters start to be a restriction at 270 L/hr. Racetronix advises against using the C5 regulator with the 340 pump. I did not listen to them and I have significant pressure drop at full throttle. Don't be me, be smarter.
Just a quick note on Fuel Pressure Regulator placement/ Component orientation.
The Fuel Pressure Regulator should be installed down-stream of the Fuel Injectors...
Otherwise a Fuel restriction can occur.
Also the Fuel Supply Line should have a Y-Fitting/ Splitter before the Fuel-Rails...
Not supplying one Fuel-Rail and then the Other.
Please reference the Image below for proper Fuel System Component orientation:
I decided to go with the 255 Racetronix kit. I'm confused on the wiring here and just want to clarify. In first pic is my spare OEM unit for comparison. What's wrong with my wiring in the other pics??? What's going on with the harness provided... seems like I'm missing something here. Do I need to take the Pink wire from the OEM fuel sending unit and pin it into the spare wire spot on the black harness plug going into the yellow plug up top? Is that it?
Does my wiring and ground look okay? I soldered the ground with a butt connector on it and heat shrunk...
Also... The pictures on their site of the kit, doesn't even show the harness that came with it. I'm talking about the 4-wire harness I have plugged into the fuel pump - yellow plug . What would the "In-tank wiring harness" shown in picture #1 be plugged into then? I am confused...
and here is the other picture of the kit, I don't see the harness I have plugged in shown here either, just wanting to make sure I am doing this right lol
no instructions or manuals anywhere that I can find, even though it's a "straight forward" job heh
I haven't done it but it seems like you just put the stuff in the places it's supposed to go.
EDIT : well, i think i have to unpin AKA cut the grey wire by the fuel pump side on the harness, and wire that onto the fuel level sender to power it...
thought it was a plug and play kit for tpi/tbi cars guess not
Last edited by AlpineWhiteIroc; Feb 3, 2022 at 10:59 PM.
also there is no way to wire the fuel level floater up properly, supplied thicker wires for what? are they implying i splice the baby wire into it? huh
pretty much useless imo
Stop worrying about the plug and start looking at wires and what they do. Put the wires where they need to be in order to mate up to wires with those functions on the outside of the tank. The terminals in the plug can be removed and moved to a different cavity in the plug if there was an assembly error by Racetronix.
I had a 4th gen hot wire kit so not same as yours, but point is I had to put my eyes on all the wires to figure out what was going on. Pull the loom off and see where the wires go, figure out what they do, draw it on paper. Then it will make sense and you'll be able to figure out which wires go where.
Just to get you started, the stock fuel pump wiring bundle plugs into connector "C313" at the base of the rear seat back.
* Pin C, (TAN wire) is the battery +12V supply for the fuel pump.
* Pin B, (PINK wire) wire is +12V from fuel level gauge.
* Pin A, (BLACK wire) is ground wire for both the fuel level gauge and fuel pump. That means those two ground wires join together into a common wire somewhere before the connector. I don't know exactly where, but you do because you have the parts in front of you in your own hands.
The Racetronix kit changes things up a bit by using the original Pin C (TAN wire) as a trigger for a relay that's part of the Racetonix harness. That relay gives the fuel pump a new, better power source with a bigger wire (probably RED) that goes to battery or alternator, whichever you choose. It also has a new, larger ground wire (probably BLACK) for the fuel pump with a ring terminal that you attach to bare metal somewhere.
Short story is look at the parts and rationalize which wires do what and you'll figure out where they need to go.
why am i using this harness? can you explain that? lol
i don't really see anyone else using it who's doing the upgrade
i see them using the 2 wire "in-tank harness"
The stock pump wires are too small for the amount of current that the new pump draws. The new wires are larger for the pump current and that's why it is included with the kit.
If you use the stock in-tank wires then the new pump won't be a 255 Liter / Hour, it will be something less than that because the power supply for the pump will be a choke point.
what are you supposed to do for the fuel level floater wire?
splice 2 separate gauge wires into eachother?
or
RUN THE 2 WIRE "IN-TANK HARNESS" and leave the stock wiring to bulkhead alone?
kit is overly confusing with 0 instructions, there's multiple ways to do it. still convinced this bulkhead connector harness is worthless unless you don't care about having a fuel gauge. not sure how they expect you to connect it to the stupid friction-washer setup on level unit. dumb
You've got the stock parts in front of you. You tell us where do the ground wires for fuel level sender and fuel pump join up? Then compare that to Racetronix wires...
At the end of the day what you've got to do is get a fuel gauge sender wire in & out of the tank, and a fuel pump wire in & out of the tank. That's 4 wires. It's obvious that the stock wiring joined the ground wires somewhere and collapsed that down to 3 wires. If that happens inside the tank then you need only 3 terminals. If it happens outside the tank then you need 4 terminals. It just is what it is, make it happen and stop the whining.
Take the loom off the wire and put your eyes on all the wires. See where things go and what it does. Draw it on paper.
I'm not answering any more questions until you put in effort to do that. Your eyes will be opened.
just curious, you didn't look at any of my pics did you? straight to the be-littling and "whining" lol.
i'm wired correctly, minus the fuel gauge sender
do I even need to use this new bulkhead connector? I have 3 wires coming out of the stock one.
why cant I just use this 2-wire harness here, like everyone else?
When I have a Customer that refuses to change-out, the Original Pass-Through Electrical Connector, for the Fuel Tank...
Originally Posted by vorteciroc
The Weather-Pack Connector is ONLY rated for a 20A Continuous Load per Terminal.
So Any of you guys that are looking to run a Big High-Amperage Pump should not use the Bulk-Head, or...
Remove the Ground Circuit from the Connector... ground the Pump to a location outside.
Then run 2 12v+ Wires through the Connector.
Now you have a total of 40A Continuous Load through the Bulk-Head.
Quick and Easy!
I even had 1 Customer that did not use a Fuel Level Gauge...
So I used all Three Terminals of the Connector (20A each = 60A Max-Continuous Load) for a Dual-Stage/ Two-Speed Electric Fuel Pump.
do I even need to use this new bulkhead connector? I have 3 wires coming out of the stock one.
You talking about this bulkhead connector? Yes, use it. It has upsized terminals to handle the higher current of the new fuel pump. The stock bulkhead is too weeny and not made for the higher current.
Don't be resistant to using the Racetronix parts. It's starting to appear like that's the only problem here.
* Look at the face of the connector at 1 o'clock in the picture. It's using 3 of 4 terminals. The 4th is probably blanked out with a rubber plug.
* Look at the connector at 5 o'clock in the picture. Seems like that is where the sender ground wire joins to the pump ground wire.
If your parts are similar then I think that answers all your questions. I'm not familiar with stock fuel tank, just making educated guesses.
* Look at the face of the connector at 1 o'clock in the picture. It's using 3 of 4 terminals. The 4th is probably blanked out with a rubber plug.
* Look at the connector at 5 o'clock in the picture. Seems like that is where the sender ground wire joins to the pump ground wire.
If your parts are similar then I think that answers all your questions. I'm not familiar with stock fuel tank, just making educated guesses.
yes...... as you can see in the 6 pics i posted above.... i'm wired correctly. MINUS FUEL LEVEL SEND, CANT CONNECT IT TO ANYTHING.
ok, so how come no one uses this harness? i can't find 1 thread of anyone using it SUCCESSFULLY. not 1 thread. just a bunch of threads of people using the short 2-wire in-tank harness.
no one is even talking about this bulkhead harness on these forums.
yes...... as you can see in the 6 pics i posted above.... i'm wired correctly. MINUS FUEL LEVEL SEND, CANT CONNECT IT TO ANYTHING.
ok, so how come no one uses this harness? i can't find 1 thread of anyone using it SUCCESSFULLY. not 1 thread. just a bunch of threads of people using the short 2-wire in-tank harness.
no one is even talking about this bulkhead harness on these forums.
I used this exact kit in my car, but I added the bulkhead connector from a 4th gen. behind the rear seat. This kit was made for the 4th gen. cars, so mine was a plug and play installation. The fuel gauge connects to the bulkhead connector along with the fuel pump trigger wire from the ECU. As an added bonus, I also ran the ABS sensor wires through the bulkhead connector. Since my battery is mounted in the rear of the car, the power wire to the battery is much shorter.
I used this exact kit in my car, but I added the bulkhead connector from a 4th gen. behind the rear seat. This kit was made for the 4th gen. cars, so mine was a plug and play installation. The fuel gauge connects to the bulkhead connector along with the fuel pump trigger wire from the ECU. As an added bonus, I also ran the ABS sensor wires through the bulkhead connector. Since my battery is mounted in the rear of the car, the power wire to the battery is much shorter.
so this bulkhead harness kit isn't SUPPOSED to be for a third gen?
if that's the case awesome, i'll put this 2 wire harness in and be done.
i am clueless, like i've posted on this thread 5 times now, why is no one using this harness, and instead ONLY using the 2 wire in-tank harness?
RACETRONIX INSTRUCTIONS USED THIS PICTURE.
You see the 2 wire in-tank harness. I don't see the bulkhead connector being swapped out, or this bulkhead connector harness being used.
so who's doing this wrong? me? if i'm doing this wrong as QWK keeps implying, then I guess I need to just plug and play the 2 wire harness and be done.
i'm wired correctly. MINUS FUEL LEVEL SEND, CANT CONNECT IT TO ANYTHING.
Just for kicks and grins, check circuit resistance from input wire to sending unit and the metal tube the unit is attached to. Tell us what is that number.
Just for kicks and grins, check circuit resistance from input wire to sending unit and the metal tube the unit is attached to. Tell us what is that number.
not here for kicks and grins or arguing, came here to fix this properly as quickly as possible.
you've avoided about every question i've asked and start rambling about where the wiring loom goes to
You're an idiot. I was just going to tell you what to do but now you can stuff it up your ***. I'm not putting up with your mouth any more.
I don't even need you to take the measurement, I see what I was wondering in your latest picture. But telling you is pointless because you won't lift a finger to help yourself.
You're an idiot. I was just going to tell you what to do but now you can stuff it up your ***.
cool?
if you looked at any of my pictures, instead of jumping to conclusions assuming i'm an idiot who doesn't know how to look at the pinning of 3-4 wires, you would HAD TO OF SEEN the same question's i kept asking over and over
You're an idiot. I was just going to tell you what to do but now you can stuff it up your ***. I'm not putting up with your mouth any more.
I don't even need you to take the measurement, I see what I was wondering in your latest picture. But telling you is pointless because you won't lift a finger to help yourself.
Enjoy your self-inflicted pain.
nope
every thread i've found shows people using stock bulkhead connector, 2 wire harness
simple : my wiring is fine as of now
you wont shut up about it
i'm just WONDERING why i'm the only guy i can find using this bulkhead harness
Originally Posted by QwkTrip
You talking about this bulkhead connector? Yes, use it. It has upsized terminals to handle the higher current of the new fuel pump. The stock bulkhead is too weeny and not made for the higher current.
Don't be resistant to using the Racetronix parts. It's starting to appear like that's the only problem here.
ok. then how come no one is replacing the bulkhead connector OR using bulkhead harness when doing this job? that would mean all these threads i'm reading are half-assing the job leaving the stock bulkhead???
I am not familiar with the Parts being discussed here (as I have never used them)...
But I do know a thing or two about the Connection Systems discussed here.
If the Image below was supposed to be an Upgrade-Part...
It is not an Upgrade-Part actually.
That Connector uses Delphi Metri-Pack 150 Series Terminals (with a 14A Continuous-Maximum Ampacity per Terminal).
This is one of the lowest Ampacity Ratings available from Delphi.
Better options over the Metri-Pack 150 Series, would be:
-The Weather-Pack Series would be good for a 20A Continuous-Maximum Ampacity per Terminal.
-The GT 280 Series would be good for a 25A Continuous-Maximum Ampacity per Terminal.
-The Metri-Pack 280 Series would be good for a 30A Continuous-Maximum Ampacity per Terminal.
If you wish to use Parts from Racetronix, use:
-RCS-028
-RCS-031
-RCS-032
Just to warn you, Racetronix lists the Delphi GT 280 Series, rated at 30A Max.-Cont.
That is incorrect, as it is actually rated at 25A.
I also use and sell those same Parts that I listed from Racetronix...
They are very good Parts!
Thanks for clarifying that. I spoke wrong and realized it too a while after I posted but lost interest in trying to help somebody that won't help themselves. Inexperienced, first timer, out of their element -- no problem, that's all fine with me. Not willing to try annoys the crap out of me though. I don't know, maybe I got a little bit of a bad attitude too....
Thanks for clarifying that. I spoke wrong and realized it too a while after I posted but lost interest in trying to help somebody that won't help themselves. Inexperienced, first timer, out of their element -- no problem, that's all fine with me. Not willing to try annoys the crap out of me though. I don't know, maybe I got a little bit of a bad attitude too....
Maybe I missed it...
But I did not see you imply that it was an Upgrade.
Thanks for clarifying that. I spoke wrong and realized it too a while after I posted but lost interest in trying to help somebody that won't help themselves. Inexperienced, first timer, out of their element -- no problem, that's all fine with me. Not willing to try annoys the crap out of me though. I don't know, maybe I got a little bit of a bad attitude too....
you missed 95% of my concerns, telling me "i won't help myself" and skipped over the confusion here that i'm having. where the wires go is irrelevant, that's a cake walk, it's simple anyone can figure that out and it was kind of insulting, man i mean the plug straight up has each wire labeled...
main question is why few people upgrade bulkhead and just plug the 2 wire in-tank harness in,
and why i am using this harness rather than the 2-wire harness and stock bulkhead unit that i see every single person use on their write up
(Racetronix sent me both harnesses, hard to understand and decide which one to use when 98% of write-ups do not show or speak of the new bulkhead connector harness I am using...)
you can wire it in with either of them
just want to make 100% sense of this kit
I just want you to know that QwkTrip has been a phenomenal Contributor and Member.
He is on this Forum every single day, giving out help to anyone in need.
He is an intelligent Individual that has brought a significant amount of Knowledge and Experience to this Forum.
I do not know where things got off, on the wrong-foot...
But QwkTrip only turns away from helping people; when the individual has not been receptive/ appreciative of QwkTrip's help.
I do not respect very many people in this World...
However QwkTrip was able to gain my respect in very short order.
Thanks, vorteciroc, your words are more kind than I deserve.
Let's do a reset here....
I'm not familiar with stock fuel tank, never played with one before. There aren't many people jumping up and down excited to help.... so I tried.... but pictures alone weren't enough because I didn't know what was right or wrong. Better description and wording of the problem would have helped me to help you. I didn't figure out until pretty late in the thread what was the issue and that your sender is case grounded. I think you realized that about the same time too.
But just to not leave anything to chance.... Looks like the factory grounded the sender by brazing a tab to the tube and snapping a wire onto it. You'll probably be in business if you do the same. The reason I asked for that resistance measurement is because I wanted to confirm it really is case grounded and not just make the assumption and send you down a useless path. It's still a smart move to take that measurement at the bulkhead connector before you button everything up (swing the arm top to bottom and verify the resistance goes between about 1.5 - 90 Ohms).
Okay, so here's the other issue.... the kit you linked earlier ( https://www.racetronix.biz/k/fl98-f7...ly/bcwa-fl98hd ) is just replacement wire for stock wires between tank and connector at rear seats. It's a baby step toward what you really need, which is a Racetronix "hot wire" kit.
The stock fuel pump wiring in our cars has a lot of voltage drop. Your 255 L/hr pump is not going to act like a 255 L/hr unless you bypass all that stock junk and lay new, larger wires to power the fuel pump. That's what the "hot wire" kit does. The "hot wire" kit bypasses all the undersized stock wiring and gives you a brand new set of 10 AWG wires for the fuel pump. The stock wiring is re-assigned a new purpose to simply operate a relay that will turn the pump on/off. The "hot wire" kit requires laying new wires in the car that did not exist, so expect to have to do that (because that's the whole point).
That's the story based on what I see here. If you have more info that changes that then go ahead and share.
Yes, QwkTrip, you hit the nail on the head of what his "issue" really was. Everything he was comparing to, was an all together different kit, and the sender being "case grounded". (didn't know they did that - thought his wire was just missing). I did the hotwire upgrade and just had the regular "hotwire" kit that you suggested that he really needed (which he does). I did not even know about this bulk head kit they came out with so I was confused until I could educate myself with what he really had. I used the new 255 pump, a new sending unit assembly, and the hotwire kit - no bulk head kit. His 1st picture of his old sending unit had the sending unit wire coming off of where the arm goes in, and the one he was trying to use did not. That, I think was the confusing part of his harness, that you quickly figured out what was going on. What I had gathered from Racetronix is that the bulk head is pinned to a common setup, BUT they also state that it may be different from what the user actually has, so they need to check and Racetronix includes a simple paperclip to do the repining if necessary according to the info. Thanks to you and Vorteciroc for putting a definite answer to this on going question for the next time it comes up! Now if the other 20 zombie threads were linked to this...lol.
