Schrader valve size

[89 Trans Am WS6]

Anyone know what size the schrader valve for the fuel system is on a 93 lt1?

Ive been looking around and i think ive determined that its -4AN..anyone know different?

Im preety sure that the autometer fuel press gauge i bought has a sending unit with a 1/8 NPT thread...

Anyone know of a adapter i could use?

I gotta look through summit i guess...

[Injuneer]

Its -4AN.

I don't know the exact layout for the 93 hard lines, but on my 94, I used an NOS #17535 -4AN 90-deg swivel fitting on the Schrader valve, ran a short -4AN hose with a 1/8" NPT male on one end, and used a 1/8" NPT brass coupling from a hardware store to connect the pressure sending unit to the hose.

The advantage of using the hose it that it allows you to tuck the pressure sending unit out of the way, like behind the PCM, and keeps the load off the Schrader valve, which is easy to break off the hard line.

The 90deg fitting helps on the 94 because it points the connection to the side rather than straight up at the cowl, and the swivel allows you to aim the hose in the direction you want. Not sure if you need the same on a 93.

NOS sells hoses with -4AN on one end and 1/8" NPT male on the other, but they are espensive. I've seen custom lengths on e-Bay for about 1/2 of the NOS cost.

[deadtrend1]

Just like Injuneer said, you need the adapters. I had gotten the part numbers of cz28 so I'm looking now to see if i can find them again.

I had to buy the stem remover (looks like a screw driver, but its in the tire section of the store) and I had to cut the handle down so I could fit it under the cowl and get it into the valve.

Heres some pics of my install ....


Heres the hose when it attaches the the schrader valve, and the 90* fitting adapter.






And the sensor away behind the PCM




And the Guage itself

[89 Trans Am WS6]

Awesome, thanks for the help guys...


I like the idea of remote mounting it better too..

On the 93s the scrader valve is on the drivers side of the intake manifold right where the big nylon fuel lines come to the fuel rail..alot easier to get to then 93+ i see...

I guess ill have no reason to cut down my valve core tool

But i think ill still get the swivel and point it tword the drivers side since the pod will be there of course..

Nice pics too tim, thanks

I also have the autometer phantom gauges, the AF and the fuel press..

Cant get a tripple pod since i dont have ttops

Thanks for the help guys and if you can find those posts on cz28 it would be greatly appreciated!

thanks, joe

[Injuneer]

NOS #17535 on the 94 fuel hard line:



Nice thing about the Firebirds is the availability of the center A/C vents....