Tried this in classic, no responses.
406, srp, total seal, scat4340, scat h-beam, arp studs, internally balanced, Sonic-checked block, etc.
Currently 195 AFR, xe274, 1.6 rr, Air-gap, 770 Holley, MSD Digital 6.

 

Should take 550-600FWHP with good bolt's.Make sure not to rattle it if you hose it.

 

Racerdude,
I've got a number of NO2 kits lying around, and I'd like to put one on this engine.
My concern is two-fold......
I don't want to damage the rotating assembly, and I'm nervous about the main-bearing speed, given the journal size.
The point of this question is, do I buy a new aftermarket block now or wait ?
This is a street car, but I don't like losing, if you know what I mean.

 

I have a 509 two bolt block sitting here and many told me if I were to push it much over 600hp it would probably split the block. SO I am opting for a nice bowtie unit.

Good luck!

 

If the clearances are right,no problem with the speed.I run Ford 351 3.00 size to 8000RPM's and 3-500HP of hose with no problem,but they have .003 clearance and grooved top half main brg's.They also have an oil pump to keep up with the clearance.Just don't rattle it.Fat is happy with NO.408CID with 400HP hose=5.teen's 1/8 mile 3000lbs-10"tires

 

Thanks for the input, 1racerdude. I'm thinking 150 shot and I'm happy to hear of your success with your combo. I don't mind leaving a little on the table, so I'll go rich on the fuel jet.

 

Hope I helped.You are welcome.

 

I'd rather build a 2 bolt 400 than a 4 bolt 400. Use some ARP bolts or studs and it'll be fine.

Because of the larger mains in the 400 crank, having a 4 bolt means having less metal in the webs around the bolt holes.

 

A guy by the name of Jack Conely use to dominate the Super Mod classes (northeast) with 400 builds ranging in size from 454-482ci. The engines were consistent and reliable enough to set a lot of records in the mid 70's. They were also turning better than 7000rpm at more than 600hp. Not to mention they were doing that with the best parts you could get back then... which isn't saying much.

What alot of guys knew about making big power with the 400 is that it's all in the block work. Conely always used redrilled deck plugs in his builds to stiffen the deck surfaces. He'd also radius the main webs where they met the cylinder banks. Typical failure point for the 400. He was also using a half-fill on the block to stiffen things up. The really big builds were only acceptable on minimum shift castings. Bores would go as large as 4.25" if all was well.

That was then. Today you have much better components. If I were building a 400, I'd definitely want a lightweight crank and recip. assembly to take some of the load off the mains. And I'd never consider using the stock torsion damper.... belongs in the round file. The block modifications and machine work has to be there IMO. So, expect a sizable machining bill to do it right. OR, you could buy a sportsman bow-tie block and start from there. Having built a few 400 based engines and knowing what they cost to put together at the 600+ hp level..... I stress that you take a look in that direction (the bow-tie).

Good luck.

-Mindgame

 

Thank's Mindgame
This engine is together already, and we did seal the deck holes before the block was decked, and the block was sonic checked, it was perfect.
I mag'd it , used arp studs, but no block fill or radius work. I'm using the Scat 4340 profiled crank and 6" H-beam rods, with SRP 4.155" pistons. It was internally balanced, so I'm using a fluidamper and a neutral-balance flex-plate. The heads are AFR 195's, 10.3 comp.,with a port matched Air-Gap and 770 street avenger carb.
The cam is a Comp XE274, crane r/r's 1.6.
This is my street car, and I've never spun it over 6000, since I'm using such a small cam anyway. It makes power [lot's of it ] from 850 to 6000 rpm, although at 5500 it's not pulling as hard. If I was to do this again, bigger heads and a roller for sure. But it runs so strong and so well that I don't wan't to pull it apart!
I'm going to try one of these nitrous kits, a small one, and window switch it at 3k and 6K.
What do you think
Doug

 

sounds like a good "Limited Street" car... i love the classes that are limited by the tire size. aka...scca

 

Sounds like a torquey broad.

Hey, as long as you can get it to stick it should propel you nicely. That can be a toughy on street tires though. NOS is always a neat idea, just try a plate setup and start small (~100hp). Tune it out and richen as you go to the larger jets.

Should be fun.

-Mindgame

 

Thank's Mindgame. And all who posted,
Doug