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I want to install a permanent fuel pressure gauge on my L98 engine. I
bought a VMS gauge that is supposed to be the top of the line. What do
i need to know about installing this? I got their installation info, but
thought maybe on of the forum readers has a few tips.
Thanks in advance.
rail mounted fuel pressure gauges are not necessary, but then again, they don't hurt anything either. I have them on both my 85 and 90 L98 engines. first of all, what year. iron head configuration differs from their aluminum head counterparts. on my 90, I bought an accel kit - a bit pricey, and it was pretty much junk, and about the only thing I could use was a brass elbow. the gauge failed within a year, and I replaced with a liquid filled marshall. you'll also need an AN4-90° elbow.
on my 85, I used a LS1 fuel rail AN4 adapter, and a 1/8 pipe, 45° elbow, again with a marshall gauge. this allows the gauge to be angled slightly for better viewing. also, on the aluminum head L98's you'll have to notch the distributor cover for gauge clearance if angled.
rail mounted fuel pressure gauges are not necessary, but then again, they don't hurt anything either. I have them on both my 85 and 90 L98 engines. first of all, what year. iron head configuration differs from their aluminum head counterparts. on my 90, I bought an accel kit - a bit pricey, and it was pretty much junk, and about the only thing I could use was a brass elbow. the gauge failed within a year, and I replaced with a liquid filled marshall. you'll also need an AN4-90° elbow.
on my 85, I used a LS1 fuel rail AN4 adapter, and a 1/8 pipe, 45° elbow, again with a marshall gauge. this allows the gauge to be angled slightly for better viewing. also, on the aluminum head L98's you'll have to notch the distributor cover for gauge clearance if angled.
My '88 has vacuum line fittings coming out of the plenum. They are
equally spaced on each side of the shrader valve. How did you clear the
fittings? I bought just about all the elbows i could find, but the right side vacuum line is in the way.
Rail mounted - pretty - but for the most part useless !!! Buy an electronic like the Autometer. You can leave the gage in the box and use as a tool if prefer to no mount permanently. Many variations can be seen in my C4 Sales Guide. Leaving the Gage in the 'box' means you can move the gage from vehicle to vehicle. I think the point here is that you want to be able to view the gage @ WOT. Before 'electronic' became possible we'd duct tape the mechanical gage to the windshield so we could view at WOT ! OMG those were the days !!!
My '88 has vacuum line fittings coming out of the plenum. They are
equally spaced on each side of the shrader valve. How did you clear the
fittings? I bought just about all the elbows i could find, but the right side vacuum line is in the way.
the setup will be the same as my 90 - you need the (brass) elbow that comes with the accel kit -
BlowerWorks does have a good point though, but the autometer setup will set you back around $230. as I said in my first post,
rail mounted fuel pressure gauges are not necessary, but then again, they don't hurt anything either.
05-12-2017, 07:19 AM
Fuel pressure gauge
