drum conversion

[gus74gus]

no,not a drum to disc conversion. im buildin a 74 gmc short bed step side as my go fast truck. i'm shaving as much weight as i can,and i was wondering if there were 73 up half tons with front drum brakes. can anybody help me on this?

[kemble]

I think you are looking in the wrong areas for speed.

[someotherguy]

What he said, and no.

Last front drums on GM light trucks were in 1970.

Richard

[vic_V8]

drum brakes add weight.....

[gus74gus]

what area should i be looking at then? i dont have tons of money,just what i can get from a local junk yard

[GreaseDog]

what area should i be looking at then? i dont have tons of money,just what i can get from a local junk yard

you are kinda in the right direction... drum brakes will add rotating mass to the front end, though you can adjust them down for less drag... though at a cost of losing their effectiveness.

if you were to swap to disc brakes on the rear, you will be decreasing rotating mass, though dragging the brake pads over the rotor surface constantly, creating a friction loss. its a big tradeoff really. you may want to look into 9C1 Caprice rear discs. they will be the proper 5x5 bolt pattern, and a good place to start for a disc swap.

what is done, or are you planning to do to the truck to make it faster? weight reduction? i could go on for days on that subject.

[gus74gus]

i have a dd for gas mileage already,so i just wanted to make a bad ass truck out of it to drive on the street maybe once a week. i've trashed the inner fenders,hood,hinges,most of the floor and rocker panels and front fenders are rotted already. but the truck is orange so it blends in well. swapped to manual steering box,going to go with the manual tilton brakes from an old circle track car. has a 9 inch with 4.11 gears and spool. motor should be about 450 horse at the wheels. i have no backing plates or drums even on the rear to keep the rotating mass down

[454cid]

.............going to go with the manual tilton brakes from an old circle track car.

You'll only be saving the weight of a brake booster......... a better idea would be to keep the power brake booster, but switch to an aluminum master cylinder. I've never lifted a vacuum booster, so I don't know how heavy they are....... it's possible that a Hydraboost setup could be lighter.

..............i have no backing plates or drums even on the rear to keep the rotating mass down

You have no rear brakes? I wouldn't do that on anything you drive on the street.

[kemble]

I don't think you have 450 HP at the wheels either. But your truck from your description wouldn't pass tech to run at my local track.

[gus74gus]

let me be thorough. the motor i feel should be 450 at the wheels. its a 60 over 350,12-1 with open chamber heads,64 cc fuellies with 2.05/.160 valves. mildly ported on the intake side,dual springs,7/16 screw in studs,guide plates,manly valves,titanium retainers,hydraulic reed cam measuring .312 duration and 598 lift 109 lsa,comp roller rockers and a tall single plane intake. the boosters are not that heavy,maybe 8 pounds with the master cylinder. but i have a bunch of left over parts from a circle track car i sold. thats where the motor,trans,scattershield,and rear end came from. the truck is nothing special,i got it from a friend thats had it sitting out in a field for about 8 years.

[1998454]

fuelie heads will not make 450 to the wheels without nitrous of forced induction. maybe 350 to wheel if major port work is done.

[gus74gus]

what makes you say that?

[1998454]

450 to the wheels is probably 500 at the flywheel and that takes a fairly serious head to make that happen. Fuelie heads were great in their time, and will still make decent power, but vortec heads will outflow them if ported and they struggle to cross the 425 mark at the flywheel. Keep in mind that back in the day every auto maker was looking to publish high hp numbers and to create a 365 hp 327 they measured power at the flywheel with no accessories belt driven, and headers usually just to get the 365 claim. You may check with a race shop for head recommendations, but i would say its going to take something like brodix track 1's to pull that number. Something that flows around 275 cfm.

[1998454]

Oh, and the lack of rear brakes is illegal in every state, and not allowed on any sanctioned track. I'm not bashing your build, but just hate to see some idiot pull out in front of you and junk your ride cause you can't stop. And a good lawyer would make it your fault for the lack of brakes.

[gus74gus]

like i said its just a truck from a field,i havent seen any trucks that body style in a while and just throwin all the race stuff i have left over at it to make something cool. i havent really seen ANYTHING,let alone a truck in a while that sounds fast,thats the whole point of this build. i thought about doing disc on the back before,but its just a redneck battle truck and i cant see spending that kind of money for them for no real gain. i do have a set of "18 degree" pro top lines on my 327,but i really felt like the fuellies were a better choice since the chambers were a bit bigger

[gus74gus]

how do i make this my profile picture?

[GreaseDog]

sell it to someone with some common sense.... you don't see the point in rear brakes, you have no business on the road.

[gus74gus]

great idea *******. why dont you go **** yourself? i said i dont see the point in paying for a rear disc conversion for it.i did not say i was never going to put brakes on the rear.

[454cid]

..........i did not say i was never going to put brakes on the rear.

Well you did say you didn't have drum brakes, so what are we to think? Not having drums, and not going to convert to disk, pretty much means no brakes.

[1998454]

You have to expect to catch a little hell when you do admit to having no brakes to save weight. Spool, manual steering and front brakes only is a hell of a scary combo. I think we've all been guilty of overlooking safety issues on past builds, at least i have! But post it here and people will give their opinions.

i have a dd for gas mileage already,so i just wanted to make a bad ass truck out of it to drive on the street maybe once a week. i have no backing plates or drums even on the rear to keep the rotating mass down