I was using the search option earlier to find out some info on the Hydra Rev Kits from AFR and found a topic on 5.7 rods in a 400 and the clearance problems and smaller base circles. I already have the cam but I have not ordered the engine kit yet. Is this going to be a problem? Anyone with a 5.7 400, did the rods hit your cam? I really need to know this before I order the engine kit. If there is going to be big clearancing problems it might be better for me to go with the 5.56 rods, but how much of a performance loss would that be?
I am glad I stumbled apon that thread, I would have hated to find that out after i ordered everything and was trying to assemble the engine.
Thanks
Jason

you'll have to grined on the rod at the rod bolt head with either 5.6 or 5.7 rod as far as i know. You MIGHT not have to do this with a small base circle cam. You shouldn't need a rev kit unless you intend to go be on 6500

This is considered a small base circle cam? and how much grinding are we talking about here? I know there people out there with long rod 400's.

i went with six inch rods and I had to take very little off. My engine builder and I just put play dough on them and turned the crank to see where they hit. Some after market rods already have them profiled for 400's if you plan on buying new one's.

I have stock rods with ARP bolts in them, so I wasnt planning on getting new ones.

also put a rap of black tape on each lobe so not to nick it. you'll hae to check each rod too...

thats a good idea

i strongly disagree with running stock rods unless you don't plan on running the car very much. The short rods in the 400's put a lot of wear on the cylinder walls. i know you may be on a budget but taking the time and money to do things right the first time will be cheaper in the long run.

I am planning on running it alot, weekends and during the week when its nice out. I have the rods already, and I am going to do it right., so I guess I will be doing some grinding I just hope its not to much

have a read... 4th pic down

http://www.chevyhiperformance.com/techarticles/6113/

wow, they got 455hp and 498ft lbs. I hope to get a little more out of my combination since I am running a bigger cam, with almost 500ft lbs, i could stand to kill a little low end tourqe. :hail: :hail:

Is a stock crank going to be able to handle this much power? The rods are stock with ARP bolts.

According to desktop dyno 2000, for whatever its worth, my engine made
503hp@5500/ 505ft lbs@4500 w/ 461ft lbs @2000

Man, at what point did it seem like a good idea to build this engine for my bird :lala:

What about this crank. it doesnt seem bad for 200 bucks. Its a scat 9000 steel crank for a 400 with 5.7 or longer rods

http://cgi.ebay.com/ebaymotors/ws/eB...category=33616

I talked to my machinist today about my engine. I get to talk to him here and there when I am taking stuff in for work. We haven't just sat down and talked about machine work and such. Today I asked him about the crank and the rods. He runs a 289 with a stock bottom end to 10grand in his race cars with stock bolts. He said that you can do that if you set the tolerances right, rod side clearance, bearing clearance, stuff like that. He seemed to think that a stock crank and rods with good bolts would hold up fine for my application. Then I asked about nitrous, he laughed and said thats different. He said at that point he'd recomend a steel crank and a good set of rods because of the stress it puts on the engine. I told him I was asking him because he'd know better than me.

you can push stock parts prety far

Yeah, thats what we are going to find out. The only reason i am still considering rods, such as SCAT cap screw rods is because I dont think i will have nearly the clearance problem with them because of the rod bolts.

I'm running Wheeler Sportsman rods. They're a 5140 I beam. They're a really nice rod, and only cost me $165 new bushed, so that I could run floating pins. It would have cost me more than that to press off the old pistons, resize & ARP, and have new pistons pressed back on. They design of them makes for much more clearance. - just my $.02

Another thing, I've seen dyno tests on different rod lengths, with absolutely ZERO difference in HP or Torque. The thing is longevity. A longer rod will give you a better rod to piston angle, thus helping the motor last longer...