400 build question
 

I have a 400 block cast number "817" and I was wondering if it would be worth using? I heard that the "509" block would be better. I was thinking about a 377 or 406. It will be going in a 2800lbs S-10, glide, 9" with 4.88 gear and a 32x17.5 tire. I am not too sure about valve train or top end right now, but any suggests would be great. If you need more info please let me know. I am look to run mid 6's in the 1/8. Thanks.

I believe my 1st 400 was a 817 casting. Like you said they are not the perferred casting but I wouldn't be scared to use it.

Re: 400 build question
 

Before you do any thing to the block have it sonic tested as we have found quite a few of the 400 blocks with thin cylinders and were on good for a stock rebuild, Don't go by core !!!!!

If you use it, definately fill it to the bottom of the water pump with ROKblok block filler, by far the best and easiest block filler to use, just make sure you follow directions, mix it soupy, and work fast, as the stuff WILL set up really quick. I would also definately have 4 bolt splayed caps installed. Which, then at that point, a SHP block from Dart, may be the way to go, then you can skip the block filler. I personaly won;t use stock 400 blocks anymore, for anything more than 450hp street engines.

Frank

I am also looking to build a 400. I have a question with rod length. What are the pros and cons for the 5.7 and 6.0 rods? I know it will change the pin height in the piston. Which is the safest, reliable choice. My motor will see 150hp shot of nitrous occasionally also.

General conciences is that the 6" rod produces more power, i know i run 6" rods in all my engines. As you may know the original 400 engine had 5.562 rods, GM did this so they could use stock 350 piston pin heigth.

JMO

Zip.

I thought the purpose of the longer rods was to reduce side load and help keep the thing together?

I run a 406 in s10 blazer stock crank, stock rods,dish pistons,vortec heads,pump gas. very low 11's budget fast 4 years running.no problems

I have a nice used less than 100 runs 406, that ran 10.20's on alky and 10.40's on gas in an s-10 that I am willing to sell cheap, if you are interested

434 in a stock block with 6 inch rods..and NO BLOCK FILLER EVER!!!..metal must expand when it gets hot, if you fill the block that is where split cylinders come from car runs 5.70s with 1.21 and 1.22 60fts and weighs 2880 with me in it and has 7 years of running on the block and have had many engines and block last alot longer than that...don't believe all the internet hype