To start out I'm building my first motor from bare block up. bought a 350 and had it decked and bored .030. I'm wanting to make a fun little street car. im wanting to reach numbers in the high 400 hundred HP and hopefully a little over 500 in torque. I'm wanting to keep it at a 10:1 or under compression. So far I've been matching up parts on paper but am stuck on pistons and cam. Parts list so far reads as (the part numbers are from summit)

-Scat Crank 3.480 stroke (Sca-910442)
-Scat 4340 Rods length 5.700 (Sca-25700)
-AFR 195cc Heads (AFR-1040)
-Edelbrock Preformer RPM Air Gap Intake (7562)
-Holley 750cfm double pumper carb

Any advice/opinion would be helpful thanks

 

Good build! I built a 355 for mine back in 08!

The first thing I would do, is keep it Fuel Injected. Unless it's already been converted over to carb. You can't beat the tuneability of Fuel Injection.

That's a good start so far. You haven't listed the pistons or Cam or if it's a roller block or flat tappet block.

My suggestion, would be to call Lunati, or Comp Cams and talk to them about what you're trying to do. Also, have you determined who your engine builder is yet?

Rule 1. Don't interfere. If you have an idea, that's fine, but I suggest telling them what you want, and letting them pick the parts (outside of your Heads which are a great decision) and possibly your cam. The main piece is, it all needs to work together and they have all the software goodies to mix and match parts to give you an idea of what will work well together.

I currently have a 355 in my Firebird and I love it. It has 320base hp, dynoed 262 at the wheels. I would suggest starting your search with this cam:

Lunati: 20080721 or
Lunati: 20080722 (this one will have a good lumpy idle roll for you because it's bigger (don't shoot me Sofa!) -- Was recommended to me by Lunati for my 400 build I'm planning)

This is a roller cam so if you're motor is flat tappet, it won't work with it unless you go with a retro-roller set up which is $$, but worth if if you ask me.

Also, for 400+hp, do you want this at the crank or at the wheels? With an automatic, and since you haven't posted it in your details under USERCP we don't know, allow for 20% drive line loss when taking the dyno reading at the wheels.

You will also need forged rods and, (I have I-beam-Scat Rotating assembly) if you stick around 400 base hp (at the flywheel), you can get away with a cast crank.

One more thing, if you really want to hit that 400hp number, since you already have the motor, bored and honed. Make it a stroker...377 or 383. You will NEVER regret it. I wish now that 6 years ago I had done it. That will get you into the 400rwhp range.

Hope this helps!

 

Torque comes from the combination of CID and compression.

You won't make 500 ft-lbs with what you're proposing, even at the crank. It'll do in the low 400s kind of range.

HP comes from high torque at relatively high RPMs. To get in the high 400s of crank HP with a 350, you need for your peak torque to be at above 5000 RPMs, and above 400 at that RPM. Clearly not a street setup. Ain't likely happenin with a N/A motor. Also, not a good choice for a beginner motor build, in a wore-out block.

If you're serious about those numbers, the little blue bottle is probably the best way to get there. If your "goal" numbers are at the wheels, it'll take about 200 - 250 HP of bottle to get there.

Meanwhile, to get what the parts you list will REALISTICALLY give you:

Have your block decked to 9.000" from crank CL to deck, and use flat-top pistons with a TRUE, AS-MEASURED compression height of 1.56". Not, "catalog says they fit engines with 1.56 in CH". Virtually ALL cast pistons, MOST hypereutectics, and MANY forged ones (including TRW / SpeedPro) add an extra .020" of deck clearance by subtracting .020" from the compression height; and will ACTUALLY MEASURE 1.54" not 1.56", regardless of what the "advertising" says. If you have any doubts, mic them; and if they AREN'T 1.56", send them back.

AFR seems to usually recommend dual-pattern cams. Since you don't say what 350 block you have, we can't tell if it supports the factory roller system or not. If it does, look at the Comp XR276HR http://www.summitracing.com/parts/cca-08-423-8. If not, look at the XE274H http://www.summitracing.com/parts/cca-12-246-3 or the Lunati Voodoo that's about the same size.

Get the valve spring upgrade from AFR. If they offer Comp 986 or 987 springs, that'd be a good choice, for any of the cams I mentioned. Definitely avoid ANY 1.25" springs. Another possible choice is beehives, but since you're starting from scratch, the larger OD springs would be the way to go.

If this is going in your 3.08 geared RS, I'd STRONGLY recommend an upgrade to a posi (NOT a stock or other Auburn, or a Gov-Lock) and a 3.73 gear; and a set of LCARBs.

 

Ya your not going to make 500 FTLBs you would have to build a 400 to hit that if your lucky. Low 400s is were your going to be. Pick a cam that will spin to 6,500 and you should have no problem hitting mid 400 HP with the parts you chose. I would keep compression in the high 9s to 10:1 if your running an automatic your going to want to have a high stall converter too like a 3,000RPM. Roller is the way to go if you can afford it. If you cant I would go solid tappet if your only driving it around town once and a while. I just don't prefer hydraulic tappet cams for hot rods. There my last choice and only something I would use if I am on a tight budget or building a motor for something like a truck. Even then I would rather use a solid tappet cam. Spend the money and get some forged pistons. I like single pattern cams for race motors over duel pattern as I feel they usually make more peak torque. Your heads flow good at high lift so I would take advantage of it and try to get something with as high of lift as you can. If you can go roller I would use something like COMP Cams#249-12-460-8 Magnum Hydraulic Roller Camshaft
Chevy Small Block 262-400 Retro Fit Lift: .600"/.600"
Duration: 304°/304°
Lobe Separation Angle: 110°
RPM Range: 3000-6500

 

I would also use a Vic JR intake.

 

I would stay Fuel Injected before I went Vic Jr. If it hasn't already been converted.

To keep some semblance of street manners, I'd caution against the Vic Jr and stick with an RPM AIR Gap. However, the Vic Jr. will get the "numbers" he's looking for.

Either way, he's going to need a 2-4" cowl hood if he doesn't stay FI.

 

The Vic JR dose pretty well on the street if your running a big stall. My father ran one for about 2 years and it drove great. I had friend that use to run one too. Both cars had 3,000 RPM stalls in them and were gutted so they were very light. My dads car had stock gears in a chevelle and my friend had 3.73 in an elcamino. My neighbor is running a strip dominator on a 327 in his 81 Camaro full weight and stock gears with a 2,500 RPM stall and a huge cam with a 650 DP. If your running a large stall converter you will never see the benefits of a duel plane intake. He drives at 2,000 RPM on the freeway and dose 200 mile round trip drives all the time going to Spokane with his car and it drives great. I do not think people relies how street able a single plane is. A friend has a Vic Jr on his jeep with a small cam in a 400 SB with 307 heads. Its a little too much intake but it also drives pretty nice. Stepping up to the AFR 210 heads would probably make better power too.

 

i just posted a new thread here is the link it has more info about the car.
https://www.thirdgen.org/forums/tech...ml#post5873080