Author Topic: Ls swap questions  (Read 9535 times)

Offline ajdmello

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Re: Ls swap questions
« Reply #15 on: August 10, 2016, 10:05:05 AM »
I guess i could just use the rubber lines with the factory steel lines didnt know if the rubber would hold up with the pressure from the new pump. I prob need to get new lines anyways be nice just to run steel lines the whole way...

Yes i would like to see some pics of what you did so i can get and idea what i need to do i think the 99 does have a return line although i need to check to be sure.


Your right i could just run that 4.8 and change it out later if is not got enough power

Offline hatzie

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Re: Ls swap questions
« Reply #16 on: August 10, 2016, 01:58:33 PM »
I guess i could just use the rubber lines with the factory steel lines didnt know if the rubber would hold up with the pressure from the new pump. I prob need to get new lines anyways be nice just to run steel lines the whole way...

Yes i would like to see some pics of what you did so i can get and idea what i need to do i think the 99 does have a return line although i need to check to be sure.


Your right i could just run that 4.8 and change it out later if is not got enough power


Stock hoses will be SAE J30R7 with a MAX working pressure of between 35 & 50 PSI and 250PSI Burst when they were new.  http://www.veyance.com/ProductsDetail.aspx?id=10526

Replace em with hoses rated for the 60PSI + the LS is expecting.  SAE J30R9 hose is rated at 100PSI working and 900PSI Burst. http://www.veyance.com/ProductsDetail.aspx?id=5144

On this same subject...
If you're using an in-tank pump be sure the hose section that mounts it to the fuel pickup tube is SAE J30R10 Fuel Submersible hose.  Most fuel pumps come with the wrong stuff.

Use German Fuel Injection hose clamps or Properly sized Constant Tension Band Clamps on your fuel hoses.  Worm clamps are not really suited to hoses smaller than 5/8"-3/4".
I don't use the cheap worm clamps even on larger hoses.  When the hoses outer jacket extrudes through the worm slots in the cheap clamps it releases the original tension and you have a leak.  Breezeliner worm clamps have an extended stainless protective tang to keep the hoses away from the worm slots for a couple more quarters but not for smaller than 5/8" - 3/4" hose.

The Pollack dual tank valve is only rated at 60PSI or less.  It probably will not work for very long at more than that.  If you use a frame mount pump you may be able to keep the dual tank valve if the return pressure is low enough.


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Offline roundhouse

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Re: Ls swap questions
« Reply #17 on: August 11, 2016, 12:16:09 AM »
I will see if I can get some pics

Been raining every day

Plus the rear main seal on the LS blew

Took 8 quarts to get 8 miles home


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Offline ajdmello

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Re: Ls swap questions
« Reply #18 on: August 11, 2016, 05:31:11 AM »
I will see if I can get some pics

Been raining every day

Plus the rear main seal on the LS blew

Took 8 quarts to get 8 miles home


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Ok whenever im in no rush

Man when you say blew it really blew! That sucks

Offline ajdmello

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Re: Ls swap questions
« Reply #19 on: August 11, 2016, 05:38:48 AM »
I guess i could just use the rubber lines with the factory steel lines didnt know if the rubber would hold up with the pressure from the new pump. I prob need to get new lines anyways be nice just to run steel lines the whole way...

Yes i would like to see some pics of what you did so i can get and idea what i need to do i think the 99 does have a return line although i need to check to be sure.


Your right i could just run that 4.8 and change it out later if is not got enough power


Stock hoses will be SAE J30R7 with a MAX working pressure of between 35 & 50 PSI and 250PSI Burst when they were new.  http://www.veyance.com/ProductsDetail.aspx?id=10526

Replace em with hoses rated for the 60PSI + the LS is expecting.  SAE J30R9 hose is rated at 100PSI working and 900PSI Burst. http://www.veyance.com/ProductsDetail.aspx?id=5144

On this same subject...
If you're using an in-tank pump be sure the hose section that mounts it to the fuel pickup tube is SAE J30R10 Fuel Submersible hose.  Most fuel pumps come with the wrong stuff.

Use German Fuel Injection hose clamps or Properly sized Constant Tension Band Clamps on your fuel hoses.  Worm clamps are not really suited to hoses smaller than 5/8"-3/4".
I don't use the cheap worm clamps even on larger hoses.  When the hoses outer jacket extrudes through the worm slots in the cheap clamps it releases the original tension and you have a leak.  Breezeliner worm clamps have an extended stainless protective tang to keep the hoses away from the worm slots for a couple more quarters but not for smaller than 5/8" - 3/4" hose.

The Pollack dual tank valve is only rated at 60PSI or less.  It probably will not work for very long at more than that.  If you use a frame mount pump you may be able to keep the dual tank valve if the return pressure is low enough.

Thats really what i wanted to know! I might just use braided line since i need to probably replace the current factory lines anyways. I  dont want to use a external pump i had figured on just using one tank for now i guess maybe down the road i will try to get the other one hooked up. I seen somewhere on here a guy using check balls in his fuel line to hook up both tanks???  Also isn there a better tank valve i could buy that will handle the 60psi?

Offline hatzie

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Re: Ls swap questions
« Reply #20 on: August 12, 2016, 04:22:42 AM »
I guess i could just use the rubber lines with the factory steel lines didnt know if the rubber would hold up with the pressure from the new pump. I prob need to get new lines anyways be nice just to run steel lines the whole way...

Yes i would like to see some pics of what you did so i can get and idea what i need to do i think the 99 does have a return line although i need to check to be sure.


Your right i could just run that 4.8 and change it out later if is not got enough power


Stock hoses will be SAE J30R7 with a MAX working pressure of between 35 & 50 PSI and 250PSI Burst when they were new.  http://www.veyance.com/ProductsDetail.aspx?id=10526

Replace em with hoses rated for the 60PSI + the LS is expecting.  SAE J30R9 hose is rated at 100PSI working and 900PSI Burst. http://www.veyance.com/ProductsDetail.aspx?id=5144

On this same subject...
If you're using an in-tank pump be sure the hose section that mounts it to the fuel pickup tube is SAE J30R10 Fuel Submersible hose.  Most fuel pumps come with the wrong stuff.

Use German Fuel Injection hose clamps or Properly sized Constant Tension Band Clamps on your fuel hoses.  Worm clamps are not really suited to hoses smaller than 5/8"-3/4".
I don't use the cheap worm clamps even on larger hoses.  When the hoses outer jacket extrudes through the worm slots in the cheap clamps it releases the original tension and you have a leak.  Breezeliner worm clamps have an extended stainless protective tang to keep the hoses away from the worm slots for a couple more quarters but not for smaller than 5/8" - 3/4" hose.

The Pollack dual tank valve is only rated at 60PSI or less.  It probably will not work for very long at more than that.  If you use a frame mount pump you may be able to keep the dual tank valve if the return pressure is low enough.

Thats really what i wanted to know! I might just use braided line since i need to probably replace the current factory lines anyways. I  dont want to use a external pump i had figured on just using one tank for now i guess maybe down the road i will try to get the other one hooked up. I seen somewhere on here a guy using check balls in his fuel line to hook up both tanks???  Also isn there a better tank valve i could buy that will handle the 60psi?

Pollack used to make a high pressure valve but they are no longer in production.

I have seen a setup where the stock TBI in-tank pumps were used as low pressure lift pumps that feed a welded surge tank.  This is probably the least expensive route.  There are stainless fuel valves but they cost several hundred dollars. 

The fellow in question used a pipe with plates welded to each end and some threaded bungs in the sides. I would probably use rectangular steel tubing rather than pipe to make it lower profile so it doesn't stick out from the frame rail as far and then install feed and return from the selector valve in one end plate with the HP pump supply on the opposite end plate and the engine return on top. 1/8" wall thickness tube is plenty with some 10 gauge for the end caps and one weld in NPT bung for the engine return.

Quoted from the linked thread.
"A simple solution is to build a small surge tank between fuel supply transfer switch and new high pressure fuel pump rated for TPI or 6.0 L operation. A purpose of a surge tank is to act as a buffer between TBI in tank pumps and provide uninterrupted fuel source to high pressure TPI pump. In another words OE, in tank TBI pumps act as fuel lift pumps, delivering fuel into surge tank. Excess, overflow fuel from the surge tank is returned back to selected tank. TPI pump takes fuel from the surge tank, via fuel filter, and return line from TPI rail dumps excess fuel back into surge tank."
http://67-72chevytrucks.com/vboard/showpost.php?p=3714312&postcount=2
« Last Edit: August 12, 2016, 04:30:57 AM by hatzie »
SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
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Radio Manuals-->http://tinyurl.com/DELCORADSVC

Offline ajdmello

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Re: Ls swap questions
« Reply #21 on: August 16, 2016, 12:38:00 PM »


Now tell me what im missing if the tbi pump is not enough to run the 60psi the motor needs how will it have enough to keep the surge tank full?

Another thought instead of doing that what if i take the extra tank and run the tbi pump in that tank and just pipe it in to the other tank with the high flow pump and put it on a toggle as along as you didnt put to much in and over fill it. Wonder if you could wire some sort of switch to stop it when its full.

Offline hatzie

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Re: Ls swap questions
« Reply #22 on: August 16, 2016, 01:20:42 PM »


Now tell me what im missing if the tbi pump is not enough to run the 60psi the motor needs how will it have enough to keep the surge tank full?

Another thought instead of doing that what if i take the extra tank and run the tbi pump in that tank and just pipe it in to the other tank with the high flow pump and put it on a toggle as along as you didnt put to much in and over fill it. Wonder if you could wire some sort of switch to stop it when its full.
Volume is not the same as pressure...  they flow enough GPH but can't build enough PSI for your injectors.

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Offline ajdmello

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Re: Ls swap questions
« Reply #23 on: August 16, 2016, 01:27:14 PM »
Ahh ok i was wondering that after i posted it. Makes sense

Offline hatzie

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Re: Ls swap questions
« Reply #24 on: August 17, 2016, 01:36:24 PM »
When you noticeably drop the pressure below the standard 13-15 psi TBI running pressure the flow in GPH or LPH actually increases.  The Slosh tank will not run much pressure.

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Offline roundhouse

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Ls swap questions
« Reply #25 on: August 19, 2016, 06:58:55 AM »
There's a company that sells classic bronco parts that sells a surge tank
Lemme look around

I installed efi from a 91 mustang on my 74 Bronco about 15 years ago

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« Last Edit: August 19, 2016, 07:06:51 AM by roundhouse »

Offline roundhouse

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Ls swap questions
« Reply #26 on: August 19, 2016, 07:03:51 AM »
Wild horses sells em
And it looks like it would work for dual tanks

I ditched the aux tank on my bronco and on the square body


http://www.wildhorses4x4.com/product/EFI_Fuel_Filter_Accumulator





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« Last Edit: August 19, 2016, 07:08:35 AM by roundhouse »

Offline hatzie

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Re: Ls swap questions
« Reply #27 on: August 22, 2016, 06:32:03 PM »
Wild horses sells em
And it looks like it would work for dual tanks

I ditched the aux tank on my bronco and on the square body


http://www.wildhorses4x4.com/product/EFI_Fuel_Filter_Accumulator





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They modified the exit by adding a pickup tube that runs to the bottom of the filter to the threaded center of the filter head.
They also added an overflow/return fitting to the top that runs to the intake side.

You can do this with a $27 Baldwin spin on filter head with four fittings on top and some copper tube for the extended center pickup.
« Last Edit: August 22, 2016, 06:34:09 PM by hatzie »
SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
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Offline ajdmello

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Re: Ls swap questions
« Reply #28 on: August 25, 2016, 08:42:35 AM »
That not really bad at all i thought it would be a lot more! I still think probably just set up one tank to get her going down the road and maybe later get a second one. Thanks for looking that up!



You think 1500 bucks will get my ls in my truck? Not counting the cost of the motor. I know computer and harness will eat up a lot of it thats about 400bucks.

Offline roundhouse

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Re: Ls swap questions
« Reply #29 on: August 27, 2016, 08:08:33 AM »
That not really bad at all i thought it would be a lot more! I still think probably just set up one tank to get her going down the road and maybe later get a second one. Thanks for looking that up!



You think 1500 bucks will get my ls in my truck? Not counting the cost of the motor. I know computer and harness will eat up a lot of it thats about 400bucks.
That's a good starting point
Fuel mods will be $300-400 when its all said and done

Mine was more since we had to buy a flywheel and clutch


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