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Author Topic:   400 SBC upgrade
Burque
Member
posted February 01, 2004 01:02 PM
I got a 406 sbc 511 4 bolt main, I was wondering what would be the weakest link in the engine. It has a 10/10 crank, recon balanced rods, and TRW forged pistons. The heads have been milled but have to check the casting numbers on them. It will be run with solid lifters headers aluminum intake and holly 350. Have not chosen the cam yet, but will as I get this engine put back together.

What would be the best parts to upgrade with say a $700 budget before putting engine back together? This will be rum on a 3/8 med banked track Street Stock division. Thanks for the help!


rico 08
Member
posted February 01, 2004 03:46 PM
The rods,a good set of rods can be had in your budget.


udecide66
Member
posted February 01, 2004 03:54 PM
Thanks for the reply Rico and udecide66!

I have not turned this engine yet it being my first year running. I believe I will be turning about 5500-6000 but we will see. The track that I will run at will have new IMCA rules that is what I'm told, with a $300 claim. I have to worry about claiming but I don't worry too much because I believe I will not be a front runner do to my inexperience.

The thing is I want to build the strongest motor for my buck along with sturdiness. I have a few extra dollars in my budget to try and build a better motor. What I want to know is the stock crank or stock recon rods or maybe even the stock 4 bolt caps should changed, or add new Vortecs. With the new changes that have fell upon me with my local track closing a different engine build up left me with an extra $700. Thanks for the help again!




udecide66
Member
posted February 01, 2004 08:47 PM
Try to find some 5.7 inch chevy rods and the pistons for them get it reballanced. If you take your time you can find deals. I got a set of SRP light weight pistons on 6 inch rods for $400.
The longer rod produces less side load on the cylinder walls and this reduction in friction will allow the engine to make more power at the rear wheels.


Raz_900
Member
posted February 02, 2004 09:53 AM
Under 6000 the stock crank and block should be ok. On a budget, get a set of 350 5.7" rods and have them resized with ARP bolts. Sealed Power or Keith Black Hypereutectic flattop pistons can be had for $250 or less and Federal Mogul/King/Clevite HP series bearings and good Felpro/Ferrea head gaskets. Oh, and ARP bolts everywhere. Main caps, heads, cam, rocket studs. Anywhere you can put them, use them. If you have the extra $$$ and plan to pull the motor down a few times, use studs. But bolts would be fine and add a great deal to the durability over the stock pieces that are now 30+ years old.

Good luck!!



chomme
Member
posted February 02, 2004 10:35 AM
Thansk for help guy's! You think i should change my pistons, I thoght TRW Forged pistons would be a better piston over hyper pistons. Am I wrong? or should I replace those too while I'm at it? Thanks again!


BrianW
Member
posted February 02, 2004 01:03 PM
quote:
Originally posted by Burque:
Thansk for help guy's! You think i should change my pistons, I thoght TRW Forged pistons would be a better piston over hyper pistons. Am I wrong? or should I replace those too while I'm at it? Thanks again!

I'll add my $.02 here - run the lightest piston you can afford - the TRW froged pistons are notoriously heavy - the hyper's are a great budget piston but you can't detonate on them as much as you can a forged - but if you're running good fuel and not running too lean they'll last as long as the forged ones do.

Like the other post said - run as long of a rod as you can. For a budget why not try a 377, 400 pistons, 350 rods and crank can be had cheap - plus they develop smooth power and like to rev.

Look at the rules you've got - you'll be limited by the carb, possibly heads and exhaust... get the rule book out and build as much engine as you can afford on a budget - try using some of the engine simulation programs out there - they'll give a good idea if you're on the right track with the heads and cam you're choosing, plus you can theoretically over-rev it and see if it continues making power or falls off and that will set the target RPM and quality of parts. (i.e. high revs=good parts) You can always de-tune it (retard timing, put throttle stop on it, etc.) until you feel you need that little extra.

I've run a budget 355 for 3 1/2 seasons - 3 in a street stock and 1/2 in a modified - turning 6000-6200 and it only consisted of a stock crank, stock rods with good bolts, hyper .250 dome pistons and it is still holding together just fine - I'm planning to tear it down this winter and see how it's going.

OH - and spend the money on a good oil pan, pump and hardened driveshaft! No engine will run when it's starved for oil!

Raz_900
Member
posted February 02, 2004 01:53 PM
quote:
Originally posted by Burque:
Thansk for help guy's! You think i should change my pistons, I thoght TRW Forged pistons would be a better piston over hyper pistons. Am I wrong? or should I replace those too while I'm at it? Thanks again!


If the TRW's are on 5.7" rods, keep 'em. If they're for stock 400 5.565" rods, sell them on Ebay and get a set of 5.7" rods and matching pistons.


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