Thread: my 305 putting out 304 HP

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I your truck is gorgeous. What are the specs on it? and did you do the theme of the truck or did you buy it like that?

Thanks man... And which truck? I have a 66 and a 85...

you can make power with any motor, 283-400. a lot of people would rather build the biggest small block they can and great. nothing like a mega horsepower sbc. i am buttoning up my 331" stroker and with smart cam choice and some serious porting and poliching onmy heads i know i will make a good number at the wheels. The secret to the small block chevy is in the cam and cylinder heads, getting the exhaust port flowing proporly will wake up any small block.

umm the truck pictured in your icon....it looks like a style i dare not say on a hot rod forum....hahaha dont hate me for thinking it...im just a dumb rockabilly anyways. and i forget your name but the guy whose building the 331...what was the base motor you started with...and could anyone find me an old small block hemi...dont know what bore o anything.

the base motor was the original block in my 81 gmc cabellero. It didnt need to be bored, just a good hone job, the cylinders where near perfect. I used a 76 400 sbc cast crank and stock 350 rods, they are slightly beefier that than the 305's. my 416 casting heads received extensive porting and polishing. opened up the exhaust ports to 1 5/8" for my headers, oldschool edelbrock torker woth a 1" spacer and a 600 holley. My cam is a custom Colt Cams 270 magnum....221@.050 465" lift with 1.5:1 roller tips all on a 108 LSA. I built this motor for 1600 canadian. Not bad for a little 305. I may add a 100 shot to it in the spring. It will see a chassis dyno and i will post the results. rest of the car is th400 with a 3000 ati stall......3:73 rear........

so you used a 400 crank and got 331? ive always heard 335 but youve done it so i think ill take your word for it. How much power and more importantly torque do you think your making?

(FUTURE 305 91 rs camaro throttle body injection) -plans i already have the car...but no money ha.

vortec heads
vortec intake
670 throttle body
lt4 stock cam
335 race block (already stroked from larrysperformance.com 4bolt)
Rebuilt T-5 tranny
3.73 rear locker
slp headers (they look pretty)
custom dual exhaust
sub frame conectors ( a must because its a convertible)

Well i hope to make around 330 hp and 340 torque. Actually i want to run circles around my sis's 98 Z
Any advie before i make any permanant changes... Do I need to get the block bored if im buying a short block?

i thought it worked out to 331 , i didnt bore it, just honed the block after the crank was ground. maybe it is 335. HP numbers are unknown, i could hazrard a guess and say 380, torque i'ld hope for just over 400. like i said i am throwing it on a chassis dyno after xmas, so we shall see. my head port and chamber work are very well done, im only running the 1.84" 416 castings. i may be able to sqeeze a bit more out if i put on my 487 castings with 1.94" intakes. lots of people have laughed at this combo i slapped together, being on a tight budget and having all these parts laying around, i just built it up. the idea of making a motor work efficiently is the key to relaible horsepower. I did my homework on camshafts and talked with a custom grinder and we came up with the 270 grind. its only a single pattern grind but it will work exceptionally well in this motor. I am using a single plane and wouldnt bother even attempting to try a dual plane. this motor will like to rev and i dont want to starve it at all. I'll gladly post the dyno results and i am going to have a sound clip and video clip with it. this cam rocks, and with the 3" exhaust aint to quiet either. But enjoyed building it and the anticipation on the dyno is killin me.........i just dont know what the real numbers will be.........

Stock bore 305, 400 crank = 329 cid
0.030" over 305, 400 crank = 335 cid

Thanks for the info tech inspector...ill keep that in mind...maybe if i just rebuild the old block i will have to do a slight over bore. oh and cabilero i cant wait to see your numbers they sound very impressive. 380!!! thats great...but still just a guess. I bet it wont be too far off tho. are you running a carb or efi? do you think that my vortec head lt4 cam combo would work...ive heard of it working but never seen it in person. and one more thing, making under 400hp would the car still need street slicks or will just regular tires be the same. i would eventually want a centrifigal style supercharger but hell, thats far off.

thank you for the info.....329 hhhmmmm, even smaller. good stuff.