world war Z, the L59/Vin Z/flex fuel thread

[littlevictories]

sigh, my LM7 turns out to be a L59 flex fuel motor.

It has flex fuel injectors, and the "ethanol compatible" regulator.

As I understand---from what I have found in my search on the subject---these injectors flow more fuel (33#/hr) at a lower pressure (~50psi).

*how is the pressure regulated down to ~50psi? -just the regulator yes?

*can i just delete the fuel composition stuff and run it on regular gas?

any insight into extra costs I might incur trying to use these injectors/harness/fuel rail would help me a bunch.

I hope I didn't get burned here.

[ls1nova71]

You can just set it up like any regular 5.3. It will run fine on regular fuel since they are designed to run on either type of fuel.

[BR3W CITY]

What year is the L59 supposed to be from? Flex fuel trucks kept the return line setup for an extra year, up to (and sometimes through) 2005.

They use a normal truck-style return system for the most part, the only differences being a FPR that is set to about ~48-54psig vs the 58 (up to 62) that the normal gas only setups are running, and different injectors. This is actually cool, for a couple of reasons.

You can swap the FPR for a regular truck fpr, but sometimes they can be a pain to find. You can also just swap the fuel rail. The advantage to this is that the Flex Fuel trucks use the car-style EV1/EV6 connector, which is way more common for aftermarket injectors. Regular trucks had the Dephi MultecII injectors (short fatties) which used a less common connector style. So you don't have to re wire or have your harness modded for that which is cool.

The flex fuel stuff can be removed from the tune, and I assume you won't be using any of the ethanol "detector" stuff the truck uses to know which fuel is in the tank.

[ls1nova71]

You can't swap a flex fpr for a regular fpr on a truck fuel rail, the rails them selves are different. Also the EV1 and EV6 are two different type of connectors. A flex fuel truck uses the EV6 where as the ls1, or car engines use the EV1.

[littlevictories]

Originally Posted by BR3W CITY

What year is the L59 supposed to be from? Flex fuel trucks kept the return line setup for an extra year, up to (and sometimes through) 2005.

I believe it to be a 2002 or 2003 based on the red&blue pcm connectors, cable throttle, and white/square oxygen sensor plugs. It does have the return style fuel rail.

Originally Posted by ls1nova71

You can't swap a flex fpr for a regular fpr on a truck fuel rail, the rails them selves are different.

This is great info. Thanks for saving me the bucks.


Given that the flex fuel injectors and FPR are not that much more expensive (currently) than the regular stuff, I'll probably just try and run the set-up I have. (with the flex-fuel programming deleted)

I have read (no direct experience) that the flex fuel injectors are more prone to clogging, especially straight from a wrecking yard. Anyone here have experience with that?

Also wondering if there is a way to bench test the FPR?


Thanks for all the help fellas. Should be about a month or so till fire-up.
So stoked!

[ls1nova71]

Just tried swapping the fpr's again and still no go.

[BR3W CITY]

Originally Posted by ls1nova71

You can't swap a flex fpr for a regular fpr on a truck fuel rail, the rails them selves are different. Also the EV1 and EV6 are two different type of connectors. A flex fuel truck uses the EV6 where as the ls1, or car engines use the EV1.

Your correct about the FPR, but the EV1 and EV6 injectors are wired with the same plug (jetronic i think)***. They are different body sizes and have different spray patterns. Some did come with a UScar connector, which has a different body. If you are running the jetronic plug, you can find both ev1 and ev6 injectors that will fit. The delphi injectors are not compatible with either.



***this is somewhat incorrect, and I updated the information further down in the next post. I didn't want to edit or delete this post for continuity, otherwise both my and the other posters comments are out of place and even more confusing.

[ls1nova71]

I think I'm losing my mind. But my LS 1s have the older style injector plug like a TPI or a LT1, that's why I deleted my comment. Isnt that the EV1?

[BR3W CITY]

Ya its a bag of fun. So injectors can sometimes be called by their manufacturer name (i.e. siemens, delphi etc), but sometimes by their body type (ev1), or their connector (MultecII, Jetronic etC). I get really backwards on this too sometimes, because when you go to double check what you know.....there are about 1000 people telling ya different things.

From the guys at FIC Injectors.

Starting with f body 98-02 uses a ev6 60mm long injector with the mini timer Bosch plug commonly called Ev1

99-2007 5.3 6.0 8.1 uses a mini Delphi plug. And a 48mm injector Except for flex fuel trucks which use a uscar plug commonly called ev6

08 up trucks all use the uscar plug and a 48mm injector

04 GTO uses mini timer plug and a 60mm injector

05-06 GTO use uscar 48mm injector

All trailblazer Ss use uscar 48mm injector

05 up corvette all use uscar. Ls2 is 48mm, ls3,7,9 is 38mm..

Lsa caddy is same as ls9, early ls1 cts uses 60mm mini timer plug same as f body

All 2010 camaro to present use uscar

Pontiac g8 uses uscar

It gets even weirder because there are injectors that are technically shaped like the EV6's, but that use the UScar plug....and vice versa. They are wired similarly, and though the plugs are different they can be adapted. As far as I can find out, they use the same timing/impedence and all that as the EV1's do.