drenner43

iTrader: (4)

What is everyones opinion on this setup? Is it easily doable? Will it hold up? I know the 4.060 bore will depend on how good the block is to start with. Will I have to clearance for the 4.125 stroke?

Also, what is the final CI of this setup?

99 Blue Bird

iTrader: (3)

a 4.125 stroke and a 4.060 bore size would make a 427 ci motor. if you were using a stock LQ block thats really its limit. i have never seen a STOCK LQ 4 inch bore turned more than .060 over so i dont think you would have a problem with it. and as far as the crank put it in and just clearance the block for the rods. the only thing is you would need to have pistons made for your setup.

PREDATOR-Z

Keep the motor square.

mark21742

I agree with Predator, once you go longer than a 4" stroke your looking at a lot more work and more stress on the motor.....if you can go with a 4.030" bore you will have a 408, and room to bore/hone the block again later down the road.

drenner43

iTrader: (4)

I'm really not too concerned about being able to prep the block again on down the road. This motor wont see a lot of abuse and will be in a light weight truck. But I do want to get the most CI possible and still be reliable to drive often. What other work is needed to go to the 4.125" stroke? I was under the impression from some reading that with the right rods the block may not even need to be clearanced. I may have misunderstood or just plain be wrong. That's why I'm asking.

99 Blue Bird

iTrader: (3)

well there is only one way to find out. are you gonna build this motor yourself or are you gonna buy parts and have a machine shop build it? if your not gonna build it its not worth going through all the hassle. it will be cheaper to buy a pre built short block. also y do you want so much motor in a truck? what are u using it for? and what kind of truck is it? if you want a reliable motor just put a bone stock 6.0 in it or even a 5.3 and leave it alone and drive it.

drenner43

iTrader: (4)

I will be having a machine shop build the motor for me. I'm not sure I understand your comment. If I'm not going to build it, what is not worth the hassle? It's just want I want, same as anybody else that loves hotrods and horsepower. The truck will just be a toy to drive pretty often. It will be a 1950 chevy.

KILLER-LS1

iTrader: (18)

as you increase the stroke, the piston travels further up and down. when it is traveling down, the skirt of the piston will travel out of the cylinder and rock back and forth, causing wear to the pistons. even a 4" stroke does this slightly. You will definitely need to clearance the block and windage tray, and also modify the oil pickup tube to get everything to fit.

stick with a 4" or less stroke. go with a 408, you wont even notice the 19cubic inches difference

99 Blue Bird

iTrader: (3)

i didnt mean its not worth having a 427 ci motor. i have thought about this a couple times. but what i ment is it might not be worth buying the rotating assembly, block, bearings, bolts, and everything to have a motor built buy a machine shop and it might be cheaper to buy a pre built shortblock from a sponsor like TSP, or AES

99 Blue Bird

iTrader: (3)

421 ci- great price for everything new and all forged internals

http://www.texas-speed.com/p-619-tsp...ort-block.aspx

gs462

iTrader: (4)

So are you saying with a 4.00 stroke its not a big deal?

SSCamaro99_3

iTrader: (1)

He is saying it is not nearly as big of a deal, and probably does not hurt too much. From everything I have read and been told, the 4.125 stroke makes the pistons very short and the wrist pins get very close to the rings. If it were me, it may be worth it for a motor primarily used in a race application. For a street toy, I would not exceed 4 inches on an unsleeved block.

1CAMWNDR

iTrader: (21)

I have an iron block with 4.07" bore filled with HardBlok up to the water pump ports. It has a 4.100" crank. 426.xxxx inches. I call it a 421 since I drive a Pontiac. I have had no porblems with it, but it does burn oil to the tune of a quart and a half every 4-5,000 miles. It has special Wiseco pistons designed for this application but I bet this is just a side effect of the short piston and coming so far out the bottom. I would really stay at 4" stroke if I did it again......

01ssreda4

iTrader: (96)

Lots of stock LS1s burn more then that.......