Safest cam with stock springs (440)

[JLM440]

I've got a 77 stock 440 thats been rebuilt, i'm wanting to get more power out of it, its in a 77 D100 1/2 ton, if i can get away with the stock springs & rockers, that would be great. i bought it like this, so i didn't rebuild it, so i really don't know what the compression is, but i'm assuming its close to stock for the year.

it has 355s with 31.5 tires, i'm planning on going to 27", a better then stock stall, 2400, & maybe a small shot of nitrous.

what cam would work good with stock springs, i'm thinking (maybe) the 474 or something equivalent or a voodoo line or comp.

Thanks..

[Shaun]

A small shot of nitrous better stay a small shot with stocker pistons and no clue on compression. It's probably low,which will be fine.
A 2400 stall converter will work good with a 230 * at .050 duration cam and nitrous like a split pattern cam(more duration and lift on the exhaust side). Comp sells K-kits,which include the cam,lifters,keepers,retainers,springs,timing chain and gears and stem seals for about $400. You should go that route and know that your setup is matched-no guesswork.
Or,you can call Jim at racer brown and he will set you up with a cam,lifters and springs(the correct cam for what you tell him you have). You'll find his contact info at 4secondsflat.com

[TK]

If you want much cam, and RPM's, you better get new springs, like shaun said. I dont really know about RB's, but smal lbocks need machine work to run over .450 safely, without mashing the valve guides.
That, and every damn time i have EVER put a higher lift cam, in a used motor, the damn valve seals went out anyway.
Me? Replace everything, get a three angle valve job done, and be done with it!
(Carefull with the NOS)

[JLM440]

Thanks guys, that was my original thought, changing everything, thats the way i like doing it anyways, but i've been listening to some other post on here where they were running performance cams with stock springs, don't know what there shifting at but i'd bet it can't be much over 5000 RPMs.

[Rug_Trucker]

If you can't afford to build it right away save your money and do it right. Valve float can get expensive. Worn stock springs etc. The only thing you can run is an RV grind.

Bouncing valves on piston tops can get really expensive.

[MrChemist]

2 reasons for changing valve springs:
1. If you go with a cam that size (about 230 degrees @ 0.050) you won’t see the real meat and potatoes of the power curve unless you get the proper valve springs.
2. If you juice it, the point at which the valves float (about 5000 RPM) comes up VERY fast in first gear…if you’re to slow to shift…KABOOM!

As far as the nitrous goes, keep it at or below a 125 shot with good fuel pressure (get an electric pump to be safe), strong spark (MSD box), 1-2 heat ranges cooler on the spark plugs (again, safety factor), and run high octane gas. This should keep it alive…then again, you never know with cast pistons (they tend to crack with nitrous use). Bottom line on nitrous use, keep the engine fat and happy. Since nitrous oxide is an oxidizer, it just wants to eat things (oxidize things to be precise), if you don’t feed it enough fuel, it will consume what ever is available…like spark plugs (if you’re lucky), pistons (if you have no luck)…

Good luck with y

[JLM440]

Originally Posted by MrChemist

2 reasons for changing valve springs:
1. If you go with a cam that size (about 230 degrees @ 0.050) you won’t see the real meat and potatoes of the power curve unless you get the proper valve springs.
2. If you juice it, the point at which the valves float (about 5000 RPM) comes up VERY fast in first gear…if you’re to slow to shift…KABOOM!

As far as the nitrous goes, keep it at or below a 125 shot with good fuel pressure (get an electric pump to be safe), strong spark (MSD box), 1-2 heat ranges cooler on the spark plugs (again, safety factor), and run high octane gas. This should keep it alive…then again, you never know with cast pistons (they tend to crack with nitrous use). Bottom line on nitrous use, keep the engine fat and happy. Since nitrous oxide is an oxidizer, it just wants to eat things (oxidize things to be precise), if you don’t feed it enough fuel, it will consume what ever is available…like spark plugs (if you’re lucky), pistons (if you have no luck)…

Good luck with your build

Thanks, i'm really not too worried about the nitrous, its just a 125 powershot, the comp in this thing is around 7.8.1, i will more then likely leave the cam alone unless i change springs too, for now i'm just going to concentrate on smaller tires & maybe alittle more stall to help propell this tank at of the hole the nitrous will be down the road when i upgrade the fue