broken rod 327

flatheadgary · Jan 9, 2009

hi guys!! i have this large journal 327 that broke the rod at the piston end and wiped the piston and rod out. the rest of the block is fine.

the piston got shoved sideways into the heads combustion chamber and the darn motor still ran.

what i was wondering is, i know the piston from a 350 will work but, will the rod also or do i have to have a 327 rod.

these are just your everyday run of the mill sbc motors. nothing fancy.

the 327 ran really good and i just wanted to get it running again.

i also have a 350 with a .030 over and i could just bore the 327 out and use the whole rod and piston assembly from it in the 327, if this will work.

i know your probably saying " why doesn't this moron just put a piston and rod assembly in it and find out?" good question!! well, the motors are buried in a shed and it will take most of a day to get at it. plus, i just figured if any of you chevy guys would like to dazzle me with your knowledge, who am i not to take it?

seriously, i am just feeling lonely and wanted to have something to say on the board.

:

i probably won't get to fixing these motors for awhile anyway.

thanks for any help offered. gary

Gearhead10 · Jan 9, 2009

Answer to your question is, yes. Large journal 327 has the same rod length (5.7) as a 350 and 305. In fact the only thing differant on the 327 is the stroke on the crank. you can acually buy a 350 rebuild kit to rebuild em. When we were buildin race engines I would take rods out of mid 80's 305 blocks, recondition them and use em in my stock car motors. See, some 305's, especialy ones outta pickups, had X-rods in them. The X is right on the main caps. They are equal to GM "pink" rods in that they are a bit stronger and made of bit better metal. I had a machine shop recondition a set for around a 100 bucks.

flatheadgary · Jan 9, 2009

thank you very much. this helps me greatly. the 30 over 350 i have needs to be bored anyway. i also have a few extra rods around here someplace.
just maybe with your help and luck, i can put together a couple of nice motors for some of my projects. thanks again,. gary

PA41 · Jan 10, 2009

It's almost embarassing what I've done to keep SBCs running

. I ran them on dirt for years in low level classes, where traction, turning and survival were the big issues. Man they will tollerate anything at 200-250 horsepower.

You can take 3-4 motors and swap parts around with little concern. I've run with one cylinder 40 over and 2 or 3 comp ratio pistons, and rods at 8 or 9 thousanths loose, and they'd rev to 6K and last till you get another one slapped together. (A high volume oil pump makes up for lotsa sins on a sloppy motor, and stock hydralics will generally float out as a rev limiter

)

The worst I've done is get the ring gaps too close and crack the rings in a tapered cylinder, or use a gualled crank.

Its fun to talk to guys that just believe what they read "ya gotta do this, or ya gotta do that"-- All you 'gotta' do is use common sense. Make sure the crank isn't galled, and the valves aren't burned up, and the Pistons aren't cracked.

Cheep set of cast iron rings, new rod bearings, cheep gaskets and timing chain and oil pump. $75-100 will get another 10-20,000 miles out of all but the worst SBCs.

"real good at barely gettin by"

PA41

Huryinhoosier · Jan 10, 2009

i thought that 327 and 350 pistons used different pin heights. The deck is the same height, the stroke is shorter so it has to be made up somewhere.

350 stroke is 3.48, 327 is 3.25. Both engines use 9.025 for factory deck height. Its gotta be made up somewhere and the piston is where.

http://www.cartechbooks.com/cartech/contentfiles/6121.pdf

Correct me if im wrong.

LordMaximo · Jan 10, 2009

Here are the specs for Chevy V8 engines:
262 = 3.671" x 3.10" (Gen. I, 5.7" rod)
265 = 3.750" x 3.00" ('55-'57 Gen.I, 5.7" rod)
265 = 3.750" x 3.00" ('94-'96 Gen.II, 4.3 liter V-8 "L99", 5.94" rod)
267 = 3.500" x 3.48" (Gen.I, 5.7" rod)
283 = 3.875" x 3.00" (Gen.I, 5.7" rod)
293 = 3.779" x 3.27" ('99-later, Gen.III, "LR4" 4.8 Liter Vortec, 6.278" rod)
302 = 4.000" x 3.00" (Gen.I, 5.7" rod)
305 = 3.736" x 3.48" (Gen.I, 5.7" rod)
307 = 3.875" x 3.25" (Gen.I, 5.7" rod)
325 = 3.779" x 3.622" ('99-later, Gen.III, "LM7", "LS4 front wheel drive V-8" 5.3 Liter Vortec, 6.098" rod)
327 = 4.000" x 3.25" (Gen.I, 5.7" rod)
345 = 3.893" x 3.622" ('97-later, Gen.III, "LS1", 6.098" rod)
350 = 4.000" x 3.48" (Gen.I, 5.7" rod)
350 = 4.000" x 3.48" ('96-'01, Gen. I, Vortec, 5.7" rod)
350 = 3.900" x 3.66" ('89-'95, "LT5", in "ZR1" Corvette 32-valve DOHC, 5.74" rod)
364 = 4.000" x 3.622" ('99-later, Gen.III, "LS2", "LQ4" 6.0 Liter Vortec, 6.098" rod)
376 = 4.065" x 3.622" (2007-later, Gen. IV, "L92", Cadillac Escalade, GMC Yukon)
383 = 4.000" x 3.80" ('00, "HT 383", Gen.I truck crate motor, 5.7" rod)
400 = 4.125" x 3.75" (Gen.I, 5.565" rod)
427 = 4.125" x 4.00" (2006 Gen.IV, LS7 SBC, titanium rods)

Two common, non-factory smallblock combinations:

377 = 4.155" x 3.48" (5.7" or 6.00" rod)
400 block and a 350 crank with "spacer" main bearings
383 = 4.030" x 3.75" (5.565" or 5.7" or 6.0" rod)
350 block and a 400 crank, main bearing crank journals
cut to 350 size

The actual 327 crank stroke is shorter from the 350 crank stroke.
Hope this will solve the great mystery

Maximo