350 short block help

[par4tom]

I apologize in advance for the length of this question:

I have a 61 chevy truck with an l48 350 2 bolt engine and 462 double hump heads. Compression is 10.25:1 and currently the motor does somewhere around 310 hp with an RV cam. It has been bored out twice over its lifetime and is about .060 over.

Edelbrock intake dual plane, msd ignition and Holley 670 Street Avenger carburetor.

The engine recently bent a pushrod and now I have a pretty bad compression problem on the #5 cylinder.

I pulled the heads and I'm going to go back through the motor which is the first time I've had to do this in almost 20 years.

Ok, so here is my objective and my parameters:

1. I m looking to make about 350 to 375 hp at the wheels using this basic set up. Not going to the strip with this truck, but want to have some fun between 0-70 mph with a lot of low end torque.

2. I do not want a temperamental motor due to tons of cam lift.

3. For aesthetics and a more genuine old school approach, I want to retain the 462 double hump heads. Currently the are the 1.94 and not the 2.02's and the block and heads were out of 67 Camaro SS.

4. The engine block is in good shape and does not need to be rebored. In fact, both the block and heads are in excellent shape.

So I go to my local speed shop with my situation, and he suggests doing a 383 stroker set up, rehoning the cylinders, porting and polishing the heads and grinding them for the 2.02 valves. These 462 heads came from the factory with both set ups as options. He also suggested dropping the compression down a bit to 9.5 to run better on pump gas.

I'm using the factory exhaust manifolds off a 66 corvette with the 2 1/2 center dump "rams horn" design. I don't plan to change these either as I just had them ceramic coated and I like more of that old school look.

What do you guys think? Anyone done one of these striker motors? How do you like it? What do you think about the 2.02 valves versus the 1.94's? Being that its a street driver and I m planning on putting on a lot of highway mileage, does it even matter?

BTW... The speed shop wants $2000 to do all the machine work including heads, block, crank valve train andvpistons. Includes assembly with roller rocker something or others (I d have to go to the taller valve covers).

Once again, I'm looking at a fun setup with lots of torque, don't need 500 hp. 400 would be great but not essential.

Does anyone have a better idea here? Or is this stroker motor a good option given my parameters.

Thanks,
Tom
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[gofastnut]

I LOVE the stroker motors, they make nice amounts of torque! $2000 isn't too bad for all the machine work. I think 2.02 valves wouldn't be a bad idea, bigger valves just feed the beast a little easier.
Bring the comp ratio down like machine shop wanted.
What are you gonna do for a cam? What ever you do, match it to the engine and vehicle.
good luck!

[bama63]

yours would be a 388 ci at your current 0.60 overbore and i have built quite a few for my race cars ,they make tons of torque and horse power at lower rpms and for 2grand with all parts and machine work sounds very reasonable. as for the 358ci you have now 400 hp is attainable but at a higher rpm range than the 388.

[Rich 5150 69]

If you can afford it go with a roller cam kit, way more power less headaches with break in than with a flat tappet cam....

[Captainfab]

To get 350-375hp to the wheels, the engine is going to have to make about 425-450hp. The easiest way to get that and be comfortable on the street is with a 383/388 or a 406.

[mud.man.rj]

Cubic inch's always rule, torque is what moves you not HP.

[Psycho75]

Personally I would have gone with a 383 had I not had a freshly machined 358 on the engine stand already. Also knocking the compression down to make it more streetable would be wise. Remember though HP equals heat but if your cooling system could handle what you were running then a 9.5:1 motor should be fine.

[par4tom]

So the 383 sounds like the right option. I'm not familiar with roller cams and why they are better. But I'm all ears.

What about valves. If you were me, would you do the 2.02's?

As far as cooling, I put a brand new 3 row aluminum radiator in. I haven't been able to drive it yet to see how we'll it works. This project is one step forward, 3 steps back...

2.02's or 1.94?
Roller cam?
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[mud.man.rj]

A roller cam setup is quite a bit more expensive, it does rev up a "bit" quicker and is the it thing to do but not a requirement for building HP. I prefer a hyd cam especially due to the lobe seperation angle (LSA) being so wide on a roller cam which makes it run a lot smoother at idle, hence doesn't sound as nice like a old hotrod used too but has a modern sound, which some may like better. Personal choice and money choice. Thing is with more torque you can run less stall in an auto and less heat plus more driveability (don't have to push the truck as hard to make it move). I build and install a big block in almost all my projects for that reason, usually in the 10-10.5 comp ratio, prefer hight 9's close to 10:1 ratio. More comp and more cam equals harder to drive.

[par4tom]

Good info Mud, thank you. You have a preference on mufflers?
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[T Smith]

Isn't a 67 block small journal? Do they make an affordable stroker crank for a small journal?

[mud.man.rj]

350 blocks don't have small journals, unless it is a 327 (early) block. I usually use Flowmaster super 44 mufflers in 2.5" to 3" depending on HP, around 450hp and up 3". I like the 44 style because they are shorter than the 40 series, they sound great and never have had a problem, I do hear a lot about Magnaflow, but have never used them yet. I know I only pay around $68 a muffler for the super 44's.

[T Smith]

OP stated the block and heads came from a 67 Camaro.....

[mud.man.rj]

Oh, cool, missed that one, maybe it is a 327 block then, he mentioned 350 so went with that.

[par4tom]

327 had 2.30 main journals. The SS 350's had the 2.45 journals. Same block, the SS 350 was machined for the longer stroke.
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[T Smith]

Did some research and the 67 L48 350 is indeed a large journal, I thought all the 67 and older small blocks were small journal, learn something every day!

Pay me no attention, I are dumb....

[mud.man.rj]

Better the large than small journal, good for you.

[par4tom]

He's right, the 67 SS Camaro was the only camaro that year with the 350. In some respects, it was a stroker for the 327 sbc. One guy I talked to swore up and down that there were no 350's in the GM lineup that year.

Btw, you can't tell the 67 327 and 350 apart. Same block same heads. Have to have the stamping off the block to ID the darn thing. That's how I figured out it was an authentic 350.
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