Home Forums Gear Hunting Trucks and Four-Wheel Drives 305 question

Yep, that is a clean truck, and I bet it feels a lot better with the 350.

It does, I can't wait for headers, flow masters , vortec heads and a new cam. Should be around 300hp and 375ftlbs makes for a nice daily driver with some punch!

Looks great Matt. Pretty clean looking... 300 HP will scoot that one down the road pretty good..

Those I would avoid. When I bought my '73 Mach 1 the previous owner installed headers and Flowmaster 40's when he had the 351 Cleveland rebuilt. It roared and had a drone at highway speeds that was absolutely unbearable. I installed Magnaflow XL's and all is good. A few weeks ago I bought a 2014 Tundra. Among other tweaks the previous owner had a Flowmaster cat-back dual exhaust system installed. It, too, roared with an even worse drone due to a single two in two out muffler. I replaced the muffler with the largest Magnaflow Straight Through and, again, all is good.

Was your Mach 1 true Dual mufflers as in two mufflers both single in single out?

Matt, flowmasters aren't bad if you go duals dumping into a single. Nothing wrong with doing that either because it helps to equalize back pressure anyway. I run a flowmaster on my 04 GMC and it sounds pretty good. It's a cat back system with bigger pipe from the cats back... With this set-up, it sounds great at idle, nice and throaty when you get on it, and not annoying on the freeway... The best I have for you as far as sound is this short video. I was playing around in 2wd in about 9" of snow after shooting at my spot....:


[img]http://i1180.photobucket.com/albums/x401/chiefbsa/th_009-11.mp4[/img]

Bud of mine had an '81 K10 pickup bought used around '84 with high mileage for it's age (50K). Stock 305 was always a dog, began causing problems at around 110,000 miles (cam, oil consumption).

He put a rebuilt four bolt main 350 in it. TRW/RV grind cam, better pistons, etc. Someone suggested he use the aluminum intake/RQJ from the 305 and that worked out well. Ran like a bear, got fairly good fuel mileage.

That engine had well over 300K on it before it was ever replaced by the next owner, years after my bud had sold it around '94.

Only 305 that I ever owned, was in an '83 work van. Fuel pump lobe went to hell at about 95,000 miles. Installed an external "pusher" elec. pump back near the tank in the "supply" line. Anytime it got balky for fuel, hit the pump switch and off she went again. Yeah I know, shade tree but it worked.

Knew another guy that had a new Blazer w/305 that dropped a valve into a piston in less than three years.

Come ta think of it, never heard any "good" reports on any 305s?

Same here. I can't stand Flowmasters.

I like the distinctive sound of flowmasters, had the original two-chamber on two Mustang 5.0's, no drone to be honest but the dynomax cat-back was absolutely horrible.

I was also in my late 20's to early 30's and enjoyed loud mufflers and straight exhaust on my cummins.

From what I can hear on youtube, I would be looking at 50 series now.

I had a good experience with the 305 in an 1984 K5 Blazer that I used for plowing snow in far NE Minnesota.

I used it from 1984 to 1993 as my recreational and work vehicle, added the plow for my own road, then picked up other jobs to keep me in some extra cash all winter. I switched out the clutch fan for a direct drive fan for cooling, and switched out the automatic hubs for manual lockers.

In addition to it being my weekend hunting/fishing rig, involving light towing, I ran about 14 plow jobs with it through some really tough winters, including 1995/1996, with over 150" of snowfall at our house, and record cold down to -45f actual air temperature (the same night Tower set the MN record of -60f Feb 2 1996).

That year in particular I can't count how many times I was either stuck due to snow falling down off the banks back into the road and piling up to stop the truck. I shoveled what seemed like over 100 tons of snow from in front of that straight plow blade. There were a lot of narrow roads on my route so I had to subcontract late winter with my neighbor to bring in a bobcat to push the snow back between the trees to make room for all the snow, which never melted much at all that winter until well into April, with snow piles in the shaded woods until after Memorial day.

Anyways that truck never used much oil, ran smooth, never made any bad engine noise, never left me stranded, always started in on the coldest mornings after sitting outside all night, and was just powerful enough to get the job done, but not so powerful that I was able to damage the front end or drivetrain.

I sold it with over 150,000 hard miles. The truck did not have a straight piece of metal on it, but the old 305 was still running strong. To this day I like it better than the 5.3 in my Suburban which consumes oil, smokes on start up, and has a piston slap on cold start up.

My BIL's Uncle has raced NHRA super stock since the 60's. Don't know what class but i do know he has to run stock displacement, iron heads and stock type carb (quadrajet), and manual trans. He's been running a 84 Firebird since the 80's. Builds his own 305's and it will snatch the tires quite handily. He's won his class at years end 10 plus times with those turd 305's. I've never owned one worth a damn but he can make them talk that's for sure.

I had an 85 GMC that puked the rear main at 83K in 1988. I dropped in a crate 350 longblock, rejetted the Quadrajet, Edelbrock headers and straight 2" exhaust with 18" glasspacks. Unbelievable difference....