Short stroked 350

[Guest goer42]

I have been doin some thinkin and trying to come up with a combination in a sbc that will scream. Has anyone done this and can it be done? 350 has 3.480 stroke, 1.56" CP right. Can I take a 283 crank and install it in a 350 block? loosing .480" on the stroke.change the rod from 5.7 to 6". then find a piston with a 1.74" CP. Do they make bearing spacers for this crank swap? I am trying to figure out a combo for our racing class. We have a 360 cu inch rule. we have to run a 2 bbl rochester with an 1 3/8" restrictor. thats not the problem. the prob is let let the 5.3 gen. 3 chevys run against us. now these engines come out of the box with 295 ft pounds of torque. everyone runs a 350 against them but i am wanting to try something different. any ideas???

[5foot2]

If this is a short track event and torque is the deciding factor i winning I'd stay far away from a 3" stroked 4" bore combo. This is the classic 301/302 SBC combo. IT's known for high revs but not for torque.

[dr_hunt]

In my experience, you need stroke to suck on that restrictor as much as possible. The trick on that is going to be cam selection IMO, needs as much lift and as much intake duration as you can get. Also run as much compression as you can muster, that'll help as well. Getting the best heads that are legal will make all the difference in the world. Are World products cast iron heads legal? If not get a set of vortec's, 291, 462 or 461 heads, put 2.02 and 1.6 valves and git r done. Solid cams will make about 8% more torque if they are legal. The 5.3's are using hydraulic rollers so if you can get one of those, you'll be way ahead of the game.

 

If your track is dry slick then tune engine and chassis for that and you'll be much faster. Pull timing out on dry slick 30 to 32 degrees total on flat tracks, a little more on banked. With stock GM heads, you can get 40 to 42 unless your running vortec's then about 34 total, run lower tire pressure and put tubes in the right rear and right front, you'd be suprised how much lower pressure you can run without it going flat. If you can run wheel spacers then add some on the right rear. Check different wheel offsets on stock wheels and pull the left wheel in as far as you can get it and put the right rear as far out as you can get it. This will help you hook better on dry slick.

 

Run gear to come off the corner at peak torque, wherever that happens. If your running a 4 speed gear it to run in 4th, less drag on the gears. Then you can go to a machine shop and have them machine off 2nd and 3rd gears off the counter shaft, save some rotating weight and still load it on the trailer and move in the pits well. If your running an auto, go with a PG, put minimal clutches in reverse and run alot of clearance on the reverse pack, it'll give you less drag and run better. Always run a glide in high gear and always run a minispool or some type of posi. Remember to vent the rear good and high and install a filler plug that is about 3/4 of the way to the top of the rear cover. Over fill the rear with the lightest rear oil, even 50W motor oil mixed with 75W gear oil. This will help you keep from burning up the left wheel bearing and give you quicker times, just make sure you warm up the rear end while in the pits before the race by jacking up the car and letting it run in gear for awhile.

 

With the wheels straight, measure the left front spindle to the center of the left rear wheel, same on right, now for leaf spring cars make the left rear about 1/4 shorter by making a new locating hole in the spring perch. This will make it go left like no tomorrow.

 

Remember in dirt racing the best handling car almost always wins. Motor doesn't hurt, but handling is where it's at to be consistent and fast.

 

Unsprung weight, reduce that as much as you can, move the shocks as outboard as far you can get those as well and still be in the rules. run gas hard shocks on the right, normal shocks on the left, unless you can run good shocks. Put zip ties around the shock shaft and "zero" them with the car sitting still and level, check them after you run and see which shock has the most travel. Increase spring rate in that corner until all shocks show about the same travel, I said about. Scale the car before and after each race, keep notes, measure ride height as well, you'll see it drop as the season goes on and you'll be able to tell if your chassis is bent from wrecks.

[Guest Phil1934]

Childs and Albert should have the bearing spacers. You don't want to give up that many cubes, though. Consider a 400 block with a 327 crank.