View Full Version : lt4 4bolt question


CHVYLT4
07-07-2005, 03:36 AM
i have a 93 lt1 and its a 2 bolt im bout to order a 396 stroker kit for it but im wondering if the two bolt block will handel it at high rpm's.... someone told me there is some main caps that i can buy where you drill out some extra holes and make a 4bolt so is this true and if not what should i do will the 2 bolt be ok or just get some good bolts and just pray it holds...
thanks chirs

JD1969
07-07-2005, 03:41 PM
I would go ahead and convert it to a 4 bolt, the machine shop will need to alighn hone it after the holes are drilled and tapped. It will add a couple hundo to your bill but it is good insurance if you ask me.

z28pete
08-11-2005, 02:36 AM
The 2 bolt mains are reliable up to about 400 HP, more than that you need 4 bolts, Your stroker will definitely need them.

JLT25
09-30-2005, 11:05 AM
I FILL LIKE A 2 BOLT MAIN BLOCK WILL HOLD UP. IF YOU HAVE A GOOD MACHINIST WORKING ON YOUR BLOCK AND ROTATING ASSEMBLY YOU'LL BE FINE. I KNOW PEOPLE WITH 383'S SPINNING 8 GRAND. 2 BOLT MAIN.

z28pete
09-30-2005, 12:56 PM
It's your engine, and it's your call, but the GM engineers decided 2 bolts were't enough to make the LT4 reliable.

JD1969
09-30-2005, 01:39 PM
agreed Pete, you all know the old saying "an ounce of prevention is worth a pound of cure", it rings true here. You could maybe get away with a two bolt but how bad will it suck if/when it comes apart and ruins the rest of the motor you just spent all that money on. Also consider this LS1's have a 6 bolt main, you never hear of anyone breaking a crank in a LS1, people run into the 9's on a stock crank, and it's all because the more bolts the bottom has the stronger it is and the less the block will flex.

Shifty_Powers
10-27-2005, 04:16 PM
one im gettin has a 4-bolt main..... they are really strong too arent they? obv. not as good as a 6 but. i know they are alot stronger and more reliable than a 2-bolt.

mattvogt
12-23-2005, 06:08 PM
yeah, they are better than a 4. good choice.

JLT25
01-02-2006, 08:02 PM
ALOT OF PEOPLE WILL SAY 4 BOLT IS THE ONLY WAY TO GO, AND IN RACING CONDITIONS YES THIS IS RIGHT. I HAVE SEE MANY PEOPLE RUN 2 BOLTS AROUND 8 GRAND 675 HP, WITH A STOCK CRANK, AND NOT HAVING ANY PROBLEMS. MY POINT BEING IT IS MORE ABOUT THE MACHINIST DOING THE WORK.