98 L36 -----> 98 LS1

[BattyV6]

I know there's a big thread going on about fueling. However, it's with different year swaps. I have a wrecked Z28 that I'm putting the LS1 into my Bird from. With the fueling, it's not direct plug-in from my V6 tank, is it? Would I be best off to swap the tank, lines, and everything? Everything else should just plug right up, correct?

Thanks
Andrew

[John_D.]

There are a couple of ways to go. The 98 v8 has no return line for the fuel. The 98 v6 does have a return line.

So....

You could swap to the 98 tank, and just not use the return line. (or to a lighter 99+ plastic tank).

Or you could keep your tank and lines. And buy a '97 vette fuel rail and fpr. (which has a return line, like your v6.) High hp v8's prefer a return type system, because the fuel pressure is more stable on the high end, so some v8 guys swap to a return type system anyway... I got my vette rail and fpr from gmpartsdirect for around $200 for my '98 swap.

[BattyV6]

Thanks a whole lot John. Does it have to be a 97 Fuel rail or is that 97+? Also do you have to get both fuel rails or just one side?
thanks

Andrew

[John_D.]

The rail is all one piece. I believe the years are '97 or '98. Here are the 2 part numbers I ended up ordering from gmpartsdirect:

12556705 RAIL $138.54
12554677 REGULATOR $34.78
Handling and Shipping: $35.66
ORDER TOTAL: $208.98

[Takumi Fujiwara]

Yea - But what about the differnt sized plug in for the regulator. - vaume line.

[slow]

you don't connect the vacuum line for the regulator, on the vette rails.

as the ls1 is looking for a 58 psi static system, regardless of its at WOT, or full vac at idle.

..... as for the first post, just swap everything, including the LS1 tank, it will be cheaper, and be like the factory installed it.

John-D

Question, how did you connect your 97-98 vette rail, to your stock rails? I am in the planning process of my return fuel system conversion, for my 1998 WS6, and was going to use the V6 lines, and the 97 vette rail/regulator (but vac/boost reference the regulator, for my forced induction)

I have put multiple posts looking for where the stock V6 lines come up in the engine bay, with no luck :( I think i may be able to use 2 of the rubber ls1 hoses, but i would love to find out before i get stuck with lines that don't work.

Thanks

Ryan.

Ryan.

[John_D.]

Originally posted by slow:
John-D

Question, how did you connect your 97-98 vette rail, to your stock rails? I am in the planning process of my return fuel system conversion, for my 1998 WS6, and was going to use the V6 lines, and the 97 vette rail/regulator (but vac/boost reference the regulator, for my forced induction)

I have put multiple posts looking for where the stock V6 lines come up in the engine bay, with no luck :( I think i may be able to use 2 of the rubber ls1 hoses, but i would love to find out before i get stuck with lines that don't work.

I haven't done the swap yet. Just got a lot of parts sitting in the garage... The old rail comes completely off, and the new rail takes it's place. The mounting points are the same.

I don't think the diameter of the fpr's are the same, so you may not be able to convert to a vac. fpr.

My vac fpr only changes the pressure about 10 psi anyway. An fmu would probably work for you instead.

The v6 lines come up on the driver's side. The rest of this I am just telling you from memory, but it should give you a pretty good idea. On the v6, they are just about even with cylinder #1. They're behind a heat shield that is about 8" tall and comes straight up. It's about 1" away the fenderwell. The hard lines come up to within about 6" of the top of the shock mount. Then the rubber quick connect lines come on over to the rail.

If the quick connect lines don't reach, you can make up your own. I had to do this when I installed an fmu for my blower on the v6. The quick connect ends were right at $10 each from Advance auto. I carried one of the old ones inside with me to make sure I got the right size. I hose-clamped a piece of high pressure fuel hose to the ends (the ends have a gripper ridge on the sealing surface about 1/4" from the end.) I see 80psi of fuel pressure when boosting, and the line works fine.

[slow]

fmu == garbage.
You can only get 14.4# of total movement on a NA motor setup with a vac referenced setup, most likely only 10 or so, as you will never get a perfect vacuum. you NEED a vac/boost referenced setup in order to tune the motork, with a 58 psi differential between the tips and the rail at all times. A FMU does not do that.

the FPR is located on the 1997-98 vette rail, normally just vented to atmosphere, to keep a 58 static system. all that is needed is to connect the vac line, and it becomes boost/vac referenced, almost like the 97-98 vettes were asking for a blower [img]smile.gif[/img]

I know the hardlines mount in the same spots, as that is why i want to use them. I just need to know if where they come up is similar to the LS1, I may just have to go to the dealer and look around.

But i won't want/won't run non OEM grade fuel components, for various reasons. That is why i need to know what kind of lines to run from the hardlines to the vette rails

Ryan.

[John_D.]

I just looked at my vette fpr (it was still in the box) and sure enough, it does have a vacuum port on it! Cool.

I had an old v6 rail in the garage. I compared it to the new vette rail. Looks like the feed line is about in the same place. The return line on the v6 is 1 3/8" behind the feed line. The return line on the v8 is 4 3/8" behind the feed line.

My experience with the vacuum referenced fpr on the v6, is that 10 lbs of boost applied to it did practically nothing. It still operated correctly from full vacuum to zero vacuum. But there was nothing added to fuel pressure after that.

When I was spraying it (dry kit) and applying some nitrous pressure to it, the fuel pressure would go to about 65 on stock pump and about 75 on boost-a-pump.

When I put the fmu on it, I could get a little over 80 psi on boost-a-pump.