Z28 Boy

if anyone has tried to run some high performance fuel lines on their TBI equipped cars...you probably ran into the problem with the threads..or finding out exactly what the threads are. well, after a ot of running around the fine city of syracuse, i called holley tech up. i spoke to a guy named scott and he hooked me up with a couple fittings that will fit directly into out throttle body (yes, they match up exactly).

it cost me 36 bucks shipped to my door for these two little gems, but i was happy to pay it (even though it was INSANELY high).

here are teh pics...

the old ones..



new ones...






they have the weird end that has that damn plastic washer, and the other end is a 6AN fitting, so you can hook up just about anything to it.

just thought i would share.

any questions just post em.

-Brian

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1991 Camaro RS
GMPP 350 HO crate engine - 454 TBI, MSD ignition, SLP exhaust, everything is new
700R4 - 2,400 stall converter, vette servo, shift kit
My car's webpage - z28boy.cz28.com
President - Central New York F-Body Association
Email - z28boy@twcny.rr.com
AIM - "Z28 Boy"

RICH92RS350

Cool! Glad to see somebody besides me that's upgrading the plumbing on their cars! What are the part #'s?
I recently upgraded the power steering lines on my RS to -6 AN also.Both Aeroquip and Earl's make adapters for these.
-Rich-

Keith5

Can we use those or some other adapters to hook up to where the hard lines come from the tank?

So that we could plum new lines from those hard lines to the throttle body and put a fuel pressure gauge in there somewhere, have it all threaded together, and not have to hack on our original fuel lines?

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1989 Pontiac Firebird Formula LO3/700R4
-180 degree stat, Hooker Cat-Back, Wonder Bar

http://www.geocities.com/krt80/

JPrevost

Of if you don't plan on running insane fuel pressure you could just cut the old pipes and use some short rubber line. This seems to have worked well for many carb and TBI guys in the past. It's especially helpful when you want to check fuel pressure.
Must admit, those look pretty nice but why did you need them?

Z28 Boy

i needed em because i wanted to use braided fuel line, which meant i had to use the hose ends that connect to the throttle body, and they are only available in the 6AN size.

-Brian

Keith5

I'd rather have all threaded connections and the braided line like z28boy wanted.

Plus I don't like to modify the orginal equipment so that it can't go back the way it's supposed to be.

[This message has been edited by Keith5 (edited November 12, 2001).]

Z28 Boy

and...from what i have heard...rubber hose longer than like 12" or something is illegal as far as a lot of tracks go. i would rather have something that i know will pass an inspection if i vere take the car to teh track.

-brian

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1991 Camaro RS
GMPP 350 HO crate engine - 454 TBI, MSD ignition, SLP exhaust, everything is new
700R4 - 2,400 stall converter, vette servo, shift kit
My car's webpage - z28boy.cz28.com
President - Central New York F-Body Association
Email - z28boy@twcny.rr.com
AIM - "Z28 Boy"

JPrevost

lol, who said is has to be longer than 12",
The Holley projection system uses normal barb fittings for rubber hose. You screw them into the stock location with teflon tape and thats that. Besides, I would just run like 8-10" till I got to my stock metal fuel lines and then hose clamp the rubber line. I guess that would require cutting the stock fuel line so you couldn't exactly go back to stock...hmmm....I don't care. It's cheap, I don't have a corvette and I'm in college , I'll go with the short rubber lines if I ever have too. Another question Brian...why are you doing this again?, lol
I'm still using my stock metal fuel lines, why aren't you? Don't they fit?

snflupigus

actually there is braided line out that you dont need the an fittings for. Aeroquip's Socketless hose fittings. And i have some adapters that that go from the pod to rubber house, so i know they are out there, and i think you get those from holley as well. Or aeroquip i bet as well.

its 1/2" to 6an and 5/8" to 4 or 6an. whichever you really want to use. 6an works for both, but you can go down to 4an on the return.

I was looking into all this a while back, so forgive me if my numbers up there are wrong, i was looking into it because i was gona run braided all the way from tank to tbi on my 69.


[This message has been edited by snflupigus (edited November 12, 2001).]

Z28 Boy

ever since i did the engine swap they didnt fit too well. at the end of this summer, i redid the 2 fuel lines with rubber and added my fuel pressure gauge. but i heard it wouldnt pass inspection at the track, and i wanted the assurance that everything was going to work flawlessly, which i know it will with the braided line.

also, it looks WAY better. and, you know me...anything i can spend money on on my car i will. i just think that the addition of the braided fuel lines and the aluminum fittings is a really nice detail under the hood, and they work really well.

the look of the rubber got old real fast, and the twisted metal look ot old even faster. just my opnion.

-brian

[This message has been edited by Z28 Boy (edited November 12, 2001).]

scauffiel

Part numbers? What kind of flow/HP will 6AN support?

S.

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Steve's Trans Am Temple

Z28 Boy

sorry guys i keep on forgetting to get the part numbers.

when i ordered them i asked the holley tech guy for the part numbers and he said that they didnt have a part number. something like they had to do some special moves in order to get them out to me.

but..i will give you the numbers on the packing slip when i get home later. they should work.

i am assuming that 6AN will flow more than enough for us. i think that most carbs etc. that can support a pretty snotty engine use 6AN. so i think that TBI is pretty well within the limits of that. but then again i could be totally wrong .

-Brian

Z28 Boy

here are the part numbers that were on the bags that the fittings came in..

8901558-39
8901559-39

hope this helps...

-brian

snflupigus

no, 6an, i was told is plenty for what most people want to run, (under 400hp)

4an is enough for our engines return because it would be a small step up from 5/16" return line which is a bit larger than 4an.

3/8" dia feed = tiny bit smaller than 6an
5/16" dia return = tiny bit larger than 4an

your stock lines, should support 400hp is what i was told, after you want over that nice mark, you will have already bought a whole new fuel system.

EROCK

do the braded lines need new fittings at the other end? I knew that they needed new ones for the TBI end but will I need ones for the other end or do they match oem?

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Teal 1991 Camaro R.S., T-Tops,
Leather, Re-worked 700r4 also w/kit,
MSD ignition, MSD 8.5 mm. superconductor wires,
MSD Coil, ADS superchip, Open element air cleaner,
K-n-N filter, Gutted cat, Flowmaster cat-back system,
Edelbrock TES headers, March 3piece billet underdrive pulleys
3.73 gears
Powertrax locking differential
http://www.geocities.com/gitarz2/camaro.html
I was shocked to see that companies sold a taillight
set for a rustang! Since when do they have taillights????

Z28 Boy

yeah they do need new fittings on the other end. i ordered what i believe to be the right ones for that, but summit and jegs were both out of stock so they are on backorder right now. they told me that they should be in within a couple weeks, so we'll see. as soon as they come i will let you guys know if they worked out.

-brian

V8Astro Captain

iTrader: (1)

Earls AN fittings also makes a part that does the same thing. I just ordered some from Summit. They were 'bout $5 a pop. I got two of each.

PN's: 991954 and 991955

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'92 Astro, GM crate 350, Holley Pro-Jection Intake, MSD 6AL, 3.42's, 2.5" exhaust, Flowmaster 40 2 chamber, B&M 2nd stage shift kit, 255 60 R15 tires on AR-727's, Polished & Bored TBI, Custom EPROM in progress

Z28 Boy

those part numbers go into the two fittings that GM supplies from the factory. the ones that i ordered go directly into the throttle body. i wanted them because it ends up being a much cleaner install. just my opinion though. i tend to be a perfectionist .

the ones that go into the throttle body are 12 and 14 mm threads, and the ones that go into the reducers that the regular fuel lines go into are 14 and 16 mm. they just reduce the thread size by 2 mm for some reason.

the fittings along the drivers side frame rail are 14 and 16 mm, with no reducers.

that was realy confusing...so if you dont understand it and need the info, let me know.

-brian

V8Astro Captain

iTrader: (1)

Oh good. I didn't really know what they plugged into (extensions or fuel metering block), all I know is I need braided line to make this Holley intake work.

Thanks for clearing that up.

Z28 Boy

well....i think they do. i am 99% positive that they do...but i dont know for sure.

i sure hope they do though or else i am gonna be screwed.

-brian

EROCK

Brian,

I am hardly ever on here anymore because of work and such. Do you think that you could e-mail me if those parts for the other end of the lines work? If so what the part numbers are again? Thanks man. I realy appreciate it!

Eric

dctrumpet

iTrader: (10)

Do you have a part number for those fuel fitting?

scooter

iTrader: (11)

hmm

dctrumpet

iTrader: (10)

HAHAHA!!! i noticed that just after i posted my question!

dctrumpet

iTrader: (10)

Unfortunately, Holley doesn't make/carry these any long. They are obsolete. I spoke with a few guys that I know there. They looked up the part numbers in their old catalogs. It was a custom part made for Holley.

Good news is I am currently in the process of making them. I have also started making fuel line extensions and rubber hose adapters as well. I have been asked to do this for years and I'm finally biting the bullet.

They both install into the back of the factory fuel nuts. On the top pair you can use a 3/8" fuel line that is fuel resistant and vapor resistant. i will not supply that. I only recommend a high grade line and clamp.

I am thinking $32 for each pair. They are made out of 2024 high-strength aluminum hex bar stock. They will come with Viton o-rings and also a pair of the Teflon washers just in case you have to remove the factory fuel fittings.

The o-rings will more than likely be the x-profile type. Chemical resistant Viton also known as Quattro Seals and X-rings, these X-profile O-rings have four points of contact for a better seal

These immediately below are the ones I am currently designing.

Schurkey

How much horsepower depends on how much pressure. Given adequate pressure, -6 or 3/8 supply tubing should support 500+ hp.
The "Dash" numbers (-4, -5, -6, etc.) represent the nominal tubing size in 1/16ths of an inch. -4 = 4/16 =1/4, -6 = 6/16 =3/8, and so forth.

Given that tubing is measured by OUTSIDE diameter, unlike pipe which is measured by INSIDE diameter, tubing wall thickness plays a part in the cross-sectional area. More than that, the ID of hose is only an approximation of the ID of tubing--and the ID of tubing varies with wall thickness. That's why they're called "nominal" sizes. Different brands of hose, different models of hose will have different IDs.

You won't know the ID of your hose until you either measure it or look at the manufacturer's specs for that model.

If your return plumbing is restrictive, you won't be able to adjust the fuel pressure low enough. I would not use -4 for TBI return plumbing. Better to be too large than too small.

dctrumpet

iTrader: (10)

We have done a number of builds for customers that have used the -6AN plumbing and they have done extremely well. Most have used the ACDelco EP381 pump. 155 and ~43psi. Several have been 375 to 385HP. At times we have slightly opened up the stock return fuel fitting as well as the -6AN fitting. There's not much room to do that, but it's been done lol.