Hello everyone! I am planning to build my 400sbc two bolt main. For now I want to build the bottom end with the notion of building the top end later as money allows. So far I have bought these parts: Scat 9000 stroker lightweight crank for the 400sbc with a 3.75" stroke and 5.7" rod length. . Scat forged I-beam connecting rods 6" . A new Comp cams part # cs xe262H-10 camshaft and lifter kit. Being that the crank is for a 5.7" rod and I am going to use 6"rods, which pistons do I buy? I got crank and rods on craigslist for $250 all sealed and brand new in boxes. Any idea would be greatly appreciated. Also, what would the combo produce as far as cubic inches and compression ? Any concerns with this build? The pistons would have to be able to clear these stock heads for now. As for heads, I am using some stock 76cc heads, but plan on upgrading to some aftermarket heads in the future. Can't afford it now, but I understand how a good set of heads would make a huge difference. I currently am using an edelbrock rpm performer manifold and edelbrock 650cfm carb. My car will be mostly street driven, weekend strip occassionally. I like to have the power when I want it, but it needs to be streetable. Thanks for any info. Suggestions on the top end would be good also, I will not be able to buy heads until later, but more info is good. Thanks, James

You need to get either a 5.7" rod for the 5.7" crank or sell the crank and get one for a 6" rod. I would recommend a larger cam too. That cam is for a stock 327/350 build. Something in the 230 duration range would be good since you want to drive it everyday. If you have any extra $$, consider a hydraulic roller cam. That way you won't have to worry about special oils/additives for flat tappet cams.

I thought I had seen in some build books, where you could use the 6" rods on that crank, but I can't remember which books. It required certain pistons I remembered were made by keith black. I'm no engine builder, so I'm only going on memory though. Does anybody know of this combo? Thanks for the info on the cam. I didn't realize that the cam was almost stock.

I've been through my share of 400 builds over the years. Just one piece of free advice. Don't piece the engine together in phases. Take whatever time you need to collect all the parts you need and build the engine the right way the first time. It will save some aggravation and you'll be glad you did it.

You can't go wrong with the JE or Ross pistons. Both are priced right and high quality. Sounds like you're looking for a mild compression.

The heads you mention will limit your performance, especially when combined with that cam. This is one of the main reasons I say wait and match your parts collectively at once. I'd suggest a 64cc head with a slightly more radical cam.

As a comparison, my old 11:1 compression 408 with Venolia pistons, Crane Fireball heads and a Comp 294S cam was driven everywhere and ran 11.30's at 3300 lbs. You should be able to achieve nice performance and driveability with the platform you're starting with.

Jim

The 6" rod will clear the crank fine. You just can't use a 5.7 rod on a crank made for 6" rods, the pistons will hit the counterweights. Use the pistons made for your rods.

I'd like to hear a machinist chime in on the "6 inch rod on crank for 5.7 rod" issue.

I agree that clearance would not be an issue but wouldn't balancing be a problem? Otherwise why would they even have cranks designed for 6" rods?

Or, I strongly suggest you call Scat and ask their opinion on it.

The 6" rods can be used. I've even seen them used on a stock 400 cast crank. But it's my opinion the 5.7's are the better play. More piston selections and probably better prices.

That cam. First, I hate the XE line of flat-tappit camshafts. Do a search on this site and others; "wiped XE lobe" and you'll be reading for days.

I'd go with a hydraulic roller. Let us know more about your goals and more about the car and you'll get some good cam advice.

Those smogger heads. Agree with one of the posts above. It makes no sense to build a performance 406 and put heads on it that will turn your 406 into a 327. What's the point?

Save some pesos and get some heads that flow. For a 406, I like something in the 210cc range. I'm strong believer in "biggish heads; smallish cam". Misery is big cam, small heads.

650 cfm carb is a bit light as well. I'd go with a 750, a DP if you drive a stick. Even a Q-Jet will flow 750 cfm and outperform the 650.

Good luck with your build.

Why do you want to use 6" rods ? I see no advantage for a street engine. When you use a 6" rod, your piston pin location must be moved by .300" for the correct compression height. (that is why you must have special pistons.) It doesn't change the cubic inch size of your engine at all. Your bore AND stroke stay the same. The only advantage that I have heard, of a longer rod is the Dwell time at TDC and the better thrust angle on your crankshaft. I don't think this will matter much on a street engine.

The 6" rods can be used. I've even seen them used on a stock 400 cast crank. But it's my opinion the 5.7's are the better play. More piston selections and probably better prices.

That cam. First, I hate the XE line of flat-tappit camshafts. Do a search on this site and others; "wiped XE lobe" and you'll be reading for days.

I'd go with a hydraulic roller. Let us know more about your goals and more about the car and you'll get some good cam advice.

Those smogger heads. Agree with one of posts above. It makes no sense to build a performance 406 and put heads on it that will turn your 406 into a 327. What's the point?

Save some pesos and get some heads that flow. For a 406, I like something in the 210cc range. I'm strong believer in "biggish heads; smallish cam". Misery is big cam, small heads.

650 cfm carb is a bit light as well. I'd go with a 750, a DP if you drive a stick. Even a Q-Jet will flow 750 cfm and outperform the 650.

Good luck with your build.

I have 327 heads on my 400 and make ~530hp or more, No intake runner porting but bowl ported and exhaust runners ported/polished

Why do you want to use 6" rods ? I see no advantage for a street engine. When you use a 6" rod, your piston pin location must be moved by .300" for the correct compression height. (that is why you must have special pistons.) It doesn't change the cubic inch size of your engine at all. Your bore AND stroke stay the same. The only advantage that I have heard, of a longer rod is the Dwell time at TDC and the better thrust angle on your crankshaft. I don't think this will matter much on a street engine.

high rpm, makes a smaller head IMO look larger

530 HP with factory 327 heads (fuelies I suppose) on a NA 400 SB?

530 HP with factory 327 heads (fuelies I suppose) on a NA 400 SB?

2850 race weight, 400 small block, GM 291 heads, 2.02/1.6 installed SO they were bowl ported and ran them for years at ~480-490hp running 10.41 to 10.45

Rebuilt the engine with the block mods and ring mods and stuff we do, same cast crank, better rods (Scat) and flat tops, ported the exhaust runners this time, same exact camshaft

normal 60' was 1.41 ,,, with rebuilt engine it has wheel hopped to an average of 1.42/1.43 yet still ran 10.19 @132.28mph with no track prep and wheel hop in the 60' (wrong springs an increased tq hitting them too hard causing bounce)

530 HP with factory 327 heads (fuelies I suppose) on a NA 400 SB?

Good amount of specs here
http://www.camaros.net/forums/showthread.php?p=1395267&posted=1#post1395267

Here is a video of it when it was 10.96:1 compression, stock block, stock crank, stock rods, OE .030 pistons, 291 heads bowl ported with 2.02's only, same cam as now, same carb and intake, really a $500 engine

10.434 in the heat with 10.96:1 junk engine
http://i510.photobucket.com/albums/s347/331Trmnatr/th_MVI_0584.jpg (http://s510.photobucket.com/albums/s347/331Trmnatr/?action=view&current=MVI_0584.flv)

Here are a few videos of new engine prepping it for this year

Cold Start
http://i510.photobucket.com/albums/s347/331Trmnatr/th_MVI_0659.jpg (http://s510.photobucket.com/albums/s347/331Trmnatr/?action=view&current=MVI_0659.flv)

Runs clean, look at headers
http://i510.photobucket.com/albums/s347/331Trmnatr/th_MVI_0660.jpg (http://s510.photobucket.com/albums/s347/331Trmnatr/?action=view&current=MVI_0660.flv)

Starts without hitting gas but batttery was about dead :sad:
http://i510.photobucket.com/albums/s347/331Trmnatr/th_MVI_0662.jpg (http://s510.photobucket.com/albums/s347/331Trmnatr/?action=view&current=MVI_0662.flv)

Little hit, not much but did spin some in parking lot, would be fun as a street/strip car :D
http://i510.photobucket.com/albums/s347/331Trmnatr/th_MVI_0668.jpg (http://s510.photobucket.com/albums/s347/331Trmnatr/?action=view&current=MVI_0668.flv)

This engine, ^^^^, is the one that has been 10.19 @132.28mph with wheel hopping 1.42 60'

I will update this weekend when we go if we get the 9.9x run we are loiking for, maybe some video