2 vs. 4 bolt mains ? - ZR-1 Net Registry Forums

va beach biker · 10-22-2006

Question on the bottom end of the LT5. Is it better to spend the extra cash to get a '93 or newer, to have the 4 bolt mains? With a normal SBC that would be a desirable feature over a regular 2 bolt. I don't have any plans for a 600 horse monster in the future, but is it still worth the money to get that beefer crank?

Aurora40 · 10-22-2006

It seems the general consensus is that the 4-bolt isn't actually that much stronger.

It's not a two-bolt like on a SBC. There is a ladder frame, kinda like having a deeper block split horizontally at the crank. So the two bolts are holding that ladder at each point, not just holding a little U over the crank.

It seems if you are going to modify it, the potential is about the same for both engines. If you keep it stock or mostly stock, well the later one has 30 more horsepower.

Z Factor · 10-22-2006

There are different reasons, both personal and practical to buy different years, but the 2 vs. 4 bolt main is not one of them.

10-22-2006	#1
va beach biker Join Date: Oct 2006 Location: Virginia Beach Posts: 46	2 vs. 4 bolt mains ? Question on the bottom end of the LT5. Is it better to spend the extra cash to get a '93 or newer, to have the 4 bolt mains? With a normal SBC that would be a desirable feature over a regular 2 bolt. I don't have any plans for a 600 horse monster in the future, but is it still worth the money to get that beefer crank?

10-22-2006	#2
Aurora40 Join Date: May 2005 Location: Leesburg, VA Posts: 2,713	Re: 2 vs. 4 bolt mains ? It seems the general consensus is that the 4-bolt isn't actually that much stronger. It's not a two-bolt like on a SBC. There is a ladder frame, kinda like having a deeper block split horizontally at the crank. So the two bolts are holding that ladder at each point, not just holding a little U over the crank. It seems if you are going to modify it, the potential is about the same for both engines. If you keep it stock or mostly stock, well the later one has 30 more horsepower. __________________ Bob Saveland Former owner of #2517 [IMG]http://a.random-image.net/aurora40/vette.jpg[/img] Last edited by Aurora40; 10-22-2006 at 02:48 PM.

10-22-2006	#3
Z Factor Join Date: Dec 2003 Location: S. Florida Posts: 2,667	Re: 2 vs. 4 bolt mains ? There are different reasons, both personal and practical to buy different years, but the 2 vs. 4 bolt main is not one of them.