basically what the title says. i am currently buildin a 355 lt1 with the forged kit from summit and forged rods and le2 package. should be round 410 to wheels and plan to give it the occassional 100 shot. will the block handle this or should i just keep it NA. thanks in advance.

 

'Ole John Lingenfelter, in his book, said that 400hp is no problem for a 2-bolt.

 

So why not convert it to a 4 bolt while you're at it.

 

Well, usually when people ask they're on some sort of budget $$. It's a legitimate question.

 

if youre worried you can always get it drilled to 4 bolt splayed which is stronger then normal 4 bolt.

Are the Lt1's similar to the L98's in the sense that around 500 hp you run the risk of cracking the block between the cylinders? dont mind me im just a third gen guy.

 

If you're going to beef up the bottom, assuming that your going to be spinning higher than 6000 grand alot, then you had at least better check to make certain your main caps are secure before putting your bolts in lest you wind up with a mess.

 

I think you'll be fine. My stock bottom-end gets more abuse than that and is still alive.

 

my old l98 ran 11.60 with a stock 2-bolt,cast crank,stock resized rodsw/arp's....3420lbs.

 

Which still amazes me and Hudini

-Dustin-

 

You will be fine till about 450-500FWHP,just make sure the shop makes sure everything is straight and true and use ARP studs.The biggest thing is cap"walk" and if you don't rattle it the chance of that goes way down. Make sure you have quality Clevitte brgs and a real good internal balance job.

 

Or an even higher quality King Alecular bearing.

A local dirt track shop says, 500 hp is a reasonable limit for 2-bolt blocks. Anything beyond that and they're going to 4-bolt.

Keep in mind that dirt track engines see a LOT of abuse. Probably one of the most brutal motorsports where parts are concerned.

Like Larry said, run studs.

-Mindgame

 

MG,

I've seen recomendations on 2 bolt studded at 400 hp from guys like CNC Blocks Northeast.

I know that on every 450+hp 7,500-8,000rpm circle track dirt and asphalt motor I've seen around here they are all 4 bolt mains, studded with forged cranks and you still go thru a crank every two seasons.

Bret

 

One of the biggest things with using 2 bolt and non forged crank is crank flex. He is using a forged and that takes care of that.
A lot of the circle track lower classes here use 2 bolt and turn them 7500. The engines usually last a season before sold. I have seen some season old engines and would not be afraid to use them again except for metal fatigue,which ya can't tell about without a lot of testing that is expensive. Hence the replacement every year.
The big dogs all run 4 bolt just for the safety and security.

 

And just who are the engines sold to? If you don't detonate the motor 2 bolts are fine. Who can share pictures of a broken 2 bolt cap on a small block? Or bearings that were pinched due to cap shrinkage? Its a piece of mind thing most everybody wants. I would use studs on a 2 bolt block and not look back unless the rest of the buildup was more max effort. The poor Ford guys have had to run cast crank 2 bolt buildups for 40 years without issue. (except for the short run Boss engines 302/351C) Only within the last 10 years have people been manufacuring "girdles" for their 2 bolt blocks and in my humble opinion they can cause more problems than they solve due to fitment issues.

I think the way the power is made might have more to do with how much reliable power a 2 bolt block can handle.

Just my thoughts.

 

I agree on the girdles.... getting those things on there correctly is the key.

Bret