12's with a 350??

[D's350GP]

Im doing a 350 build and i want the most out of my motor as possible,so just out of curiosity what would it take for a chevy 350 powered car to run mid 12's? Or is this even realistic for a motor that size without some form of forced indction, or spray? I'd like to be able to give some of the LS1 guys a run for their money on the street, and out of the box they can run mid/low 13's.

 

[mrapii]

A SBC 350 or 383 with good heads, agressive cam and 10:1 cr should get you into the mid 12s with 400+hp. This assumes good rear gearing and the ability to hook-up the tires.

 

[383Camino]

Hes right. Gears and traction will make that run 12s. Otherwise 400hp won't make it.

 

[D's350GP]

thanks, do you think taller gears would be a problem on the freeway?

 

[gwiz]

In my humble opinion, the best bang for the buck approach would be to use a 350 with late model vortec heads. A friend bought a late model chevy truck 350 long block with vortec heads already on it. He paid $500 for the engine and added an Edelbrock air gap intake and Holley 750 carb. He chose to have his heads modified following a Car Craft Magazine article (search the carcraft.com archives section for more info). The mods were needed due to the big cam he wants to run. This engine should hopefully make about 430 horsepower on a low budget. This engine won't have fancy internals, but considering how many guys we've seen run these in circle track cars and the fact that this will be his street car, plus the low price, he's not overly concerned.
The other guys are right, gearing and traction are also a factor. On the street, traction is always unpredictable, but of course those ls1's will have the same trouble and probably won't run 12.50 on the street. Personally, I wouldn't want to run much more than 3.42 gears maybe 3.73's in my street car without overdrive.
Also rembember your car's weight. Any weight you can save is like adding horsepower.

 

[82355supreme]

My Cutlass has a 355 SBC that is home built with stock iron heads, (not telling you the rest) & it runs 13.1 ET with 3.73's & a TH350 trans. on good D.O.T. tires

Now, the buddy of mine who helped me build my engine has a Monte Carlo w/ a 377 SBC & he runs 12 FLAT with no gas or forced induction on 31in. slicks. He's got approx. 475 HP & 450 Ft.lbs. too.

So, mid 12's is easily within reach on a 350 based SBC.

 

[383Camino]

Being born in the age of overdrive, I am spoiled and I think 3.55s are about all you'd want to run in a car that sees alot of street time. On the other hand, my dad thinks tht 4.10s are fine. Its all up to you.

At 60 I am at 2,500rpm with a 28" tire and 3.42s. 73mph sees about 3,000rpm.

 

[steve 86]

O.K....dont overthink it, what i mean is that theres 100 ways to build a sbc to make enough power to do the job, so really the name of the game is 60 ft. times because lets face it, after that your just along for the ride, meaning that your set up probably isnt going to be so hairy that you really have to "drive" the car to go straight. A good rule of thumb is that for every 10th you cut of your 60ft. its about a 10th. a half-a 10th. and 3/4 of your e.t. .........................so what im trying to say is dont spend $$$$ money making the engine go 12's, spend it making the whole car go 12's, I find that its cheaper and the car has more streetability and better ride Quality. gears(as mentioned by others) ,posi obviously,good lower control arms,rear sway bar if you dont already have one, and just a little mor converter than you think.I never used to believe this theory until about seven years ago when i saw people running engines on the fringes of low 13's in heavy A-bodys that were built out of spare parts and used cams.




P.S. did i mention tires and exhaust?

 

[383Camino]

I'm with him. I am about done doing engine work. Now its traction time.

 

[FLY_THE_BOWTIE]

383,vortech heads, comp cams extreme cam 268/280 dur with 468/480 lift
edel rpm performer intake will make over 400 hp with good tune. i dont know how heavy your car is, i ran a 383 with ported double hump heads#291, a 305 dur comp hyd cam, 10-1 comp, victory jr intake, holley 750 dp, turbo 350 trans 3000 rpm converter, 8.5 10 bolt with 3.08 gears in a 63 nova, 3150lbs with me and the car went 12.6 @ 108 mph. with a cage( to stiffen chassis and more gear) car would have gone low 12s-high 11s. also used 235/60-15 bf goodrich radial ta street tires on back