Longtime Owner, First Time Poster; Direction Appreciated!

[Eskay]

Howdy gang, I figured I had enough to do to my GMT that I might as well finally register for the forum. I've always done my own work on my cars and bikes, but I usually do threads on my projects to track my work when doing things beyond basic maintenance. I've previously been active on Toyota truck and RX7 forums, but my C1500 has been mothballed long enough that it's needing more than basic love and winter break has me looking to do a bit of that. It's a 1998 Silverado with the OG Vortec 5000 and 275,000ish miles; I've had it about 10 years, but my granddad had it from about 2000 until then. Currently having a weird intermittent stalling issue that acts like bad fueling, but I haven't looked into it much yet. All I really haul these days are motorcycles and car parts for other projects, so the 5.0 doing better on fuel than power works for me. I understand this vintage of 4L60 isn't generally supposed to last this long, but it looks like I might have access to a low-mile donor truck, so a three pedal swap might be in the not-so-distant future for it. It's been in my family most of my life and I'm determined to keep it, so it might eventually get the full restomod-million-horsepower-LS treatment, but I reckon it's got a lot of regular truck-stuff to do for other projects/interests before then.

As for direction, I don't really have any power goals for the L30, but any known resources or experiences with refreshing one a bit (particularly the valvetrain department) are appreciated!

 

[JOHNGAAA1]

Welcome to the forum. Anything you have that you can fix is better than the JUNK GM is building now.

 

[GrimsterGMC]

Welcome, there is nothing wrong with a 305 if it is doing what you need from it, and 275k is nothing if you keep fresh oil in it and keep it tuned. Post some pics so we can all enjoy it.

 

[RacerM95]

Eskay, another RX-7 guy ? geez

 

[Erik the Awful]

another RX-7 guy ?

SA, FB, FC, FD? I'm an old-skool FB guy.

 

[RacerM95]

Eric, 85 FB GSL-SE getting an ORIGINAL Imsa GTU wide body kit, 13b with Holley 650 flowed to 786, RB Race Race Header and exhaust for street use, Raced and drove FB's for many years...

 

[Erik the Awful]

I had a batch of '83 GSLs. I still have a 12A half-bridge with dual Weber 36 DCDs sitting in my shop.

 

[RacerM95]

How are those half bridge engines... I have only run street port engines, biggest was a Weber 50 DCOE

 

[Erik the Awful]

My Webers are set up with larger secondaries, so the half-bridge is like a poor man's VTEC. Up to half-throttle it acts like a heavy street port on just the primary carburetor barrels. Once you get above 3000 rpm you mash the gas pedal to open the secondaries and you have a full-race bridgeport. The engine has hardened stationary gears, so the recommended redline is 9000 rpm, but first gear is so short you can't slam second fast enough. I hit 10k many times. It's pretty amazing, and I really need to get the engine into my Sunbeam Alpine.

But what are your plans for your truck? Is a 350 in the future?

 

[RacerM95]

Plans for my truck, dont know right this min. I need to bail my kid out of his truck dilemma.. My best course of action is to sell him my EC Diesel 1 ton,and buy another truck.(95 GMC Sierra SLE C1500 eclb) He already cut the rear end out of mine to fix his after he spit the back axle shaft out.


Speaking of kicks in the pants Rotarys, I have always wanted to try a spread bore 4 barrel (Carter Thermoquad or similar) on a Rotary. The Primaries are the same size as the primaries on an early 12A.. so you could expect the same economy/power as stock, As soon as you put your foot into it the Beer Can Secondaries open up pouring alot more fuel in hehehehe...