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Ok here is the deal, I bought a b&m 142 supercharger with the intake and belt. I also found a deal on a forged crank, forged 6 inch rods, and forged blower pistons. I am currently looking for a sb 350 which I plan to bore out .30 over. I have a few questions:

1. I know everywhere is different but what kind of price would I be looking at to get the block dipped to clean it and bored .30 over?

2. Besides the internals that I already have I know I will need a cam but what else will I be needing? I am going to use the long nose water pump, alternator, power steering and all the other stuff on the front of the engine from the current engine that is in my car now.

3. Anybody have good head recommendations? This is a budget build so I don't want to go with a top dollar set of heads but a decent pair will do for now.

Any help on this build would be appreciated because neither my dad or I have dealt with blower motors and it's something we want to try to get into.


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383 sbc 142

Good luck with your project, I got got block ready for 100 dollars, the cam is from crower is in Otay Mesa Ca. For another 100 dollars the bad thing I don't remember the specification. I got Brodix heads 195 titanium valves 850 dollars. I'm happy with the sound and power. Probably what is more expensive is the little things. Great project
 

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What are the plans for the car? That blower is not going to make a huge power difference. From what I understand, they make about 4-6 lbs of boost. I would ask some local car guys in you area who does their machine work and ask the shop directly for info.
 

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Discussion Starter #4
Good luck with your project, I got got block ready for 100 dollars, the cam is from crower is in Otay Mesa Ca. For another 100 dollars the bad thing I don't remember the specification. I got Brodix heads 195 titanium valves 850 dollars. I'm happy with the sound and power. Probably what is more expensive is the little things. Great project
Someone else mentioned the brodix heads to me before also. I will have to check them out.


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Discussion Starter #5 (Edited)
What are the plans for the car? That blower is not going to make a huge power difference. From what I understand, they make about 4-6 lbs of boost. I would ask some local car guys in you area who does their machine work and ask the shop directly for info.
The car is just a nice street car with some track time but not a true track car. I'm not looking for 700hp. I would be happy if I can get it in the 500 area which I heard is doable. The pulley I have i was told would make between 6-10 pounds. Eventually I want to go to the 6-71 route but after talking to a guy who runs the 6-71 he said it would be good to learn to tune and all that on a smaller blower because they are more forgiving. I believe him since he is running around 24 pounds on the street with about 1000 hp. Wicked car.

I wanna build the motor right the first time do when I decide to move up, it's a bit smoother.


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If it is not the 10 Rib pulley you can forget about high boost. The belt will slip. Do you have the drive snout for the long water pump? Just asking because short and long setups are different. Like was said they are more for show but make a slight whistle while you drive. I ran mine with 441 casting heads and the car still ran great. The real trick is having a correct cam ground for the blower. The blower will help the intake side but generally the exhaust side needs help. Mine was a crane cam, with a bigger exhaust lobe. I believe it was like .518, .555, the duration I can't remember.
 

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Discussion Starter #7
If it is not the 10 Rib pulley you can forget about high boost. The belt will slip. Do you have the drive snout for the long water pump? Just asking because short and long setups are different. Like was said they are more for show but make a slight whistle while you drive. I ran mine with 441 casting heads and the car still ran great. The real trick is having a correct cam ground for the blower. The blower will help the intake side but generally the exhaust side needs help. Mine was a crane cam, with a bigger exhaust lobe. I believe it was like .518, .555, the duration I can't remember.
I'm not looking for high boost with this blower, it is 95% street. It is for a long nose water pump based on the measurements. I know it won't whittle really hard because most of the big blowers whistle because of the design of the belts and pulleys. I will be buying a blower specific cam.


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Doug Herbert has new (GM, Dart) and Seasoned/used GM ready to build blocks. With all machine work the block requires. BORE, Decked, cam bearings, line-honed (if needed). All IN HOUSE WORK, Ready to assemble.

Also Herbert Cams has a strong reputation with blower engines. From flat tappet & roller. The Herbert's know blowers!



Al
 

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Al you're gonna get in trouble again. :devil: RICK
 

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I hope not either. NPHNP is the reason for being here. The BSing is just a plus. Ok talk to you later I'm off to the world finals. Go Capps!!! RICK
 

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I have a B&M 144 on my 350 and am quite pleased with it.
I 'd highly reccomend using aluminum heads ; you'll have fewer detonation problems. I'm using edelbrock rpm heads and the rpm cam.
Old b&m literture listed their "super street cam" with specs of .488/.510 lift and .234/244 duration with 114* lobe separation.
You'll need to consider the combustion chamber size of the heads to match your desired cr using your blower pistons... how big a dish cc wise are the pistons.
Trying to select a cam and cr that best suits the small blower maybe a big compromise for a 6 71.
As far as noise; mine's pretty loud when making boost.
'
 

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Discussion Starter #13
I believe if I remember right the piston were a 12cc dish but I can't remember for sure. I bought them a while ago. I know I figured they would pull me down to the 8:1-8.5-1 ratio with 64cc heads I believe. I would have to go back to all my stuff I was looking at. A set of heads is really what's actually holding me up. Just waiting till I can afford a pair. And I want to go aluminum for sure.


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I have a B&M 144 on my 350 and am quite pleased with it.
I 'd highly reccomend using aluminum heads ; you'll have fewer detonation problems. I'm using edelbrock rpm heads and the rpm cam.
Old b&m literture listed their "super street cam" with specs of .488/.510 lift and .234/244 duration with 114* lobe separation.
You'll need to consider the combustion chamber size of the heads to match your desired cr using your blower pistons... how big a dish cc wise are the pistons.
Trying to select a cam and cr that best suits the small blower maybe a big compromise for a 6 71.
As far as noise; mine's pretty loud when making boost.
'
And it's good to hear that you like your 144. You can definitely feel the power with it as apposed to without it?


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O wow. I would assume there is a nice difference then. This sounds more reassuring then considering an earlier poster said there wasn't a big advantage to have one of these blowers.


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Old b&m literture listed their "super street cam" with specs of .488/.510 lift and .234/244 duration with 114* lobe separation.
You'll need to consider the combustion chamber size of the heads to match your desired cr using your blower pistons... how big a dish cc wise are the pistons.
'
This was the first cam I ran in the motor. When I had the heads done over, I swapped to the Crane. Mine was 8.5-1 with dish pistons in a 355. But to repeat my point, in the old catalog, it had a chart for pulleys. I had a pulley that was supposed to make I believe 8 lbs boost. It was supposed to make it equivalent to an 11.25-1 compression engine. However with the 6 groove pulley setup, I just could not get it to not slip at high rpm. This is where a 10 groove setup is needed. And like was said in one of the last posts, if you keep it to 5-6 it will be fine. Any more boost than that, and all you do is build heat with the blower because you have to spin it so fast. This is where the much larger blowers at lower speeds benefit greatly.
 

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I'm just doing some thinking about boost and what my old engine builder and I discussed many years ago about blowers.

People list boost capabilities, but the motor in a small way determines the amount of boost any particular motor might see.

If you're running a small cam and small valve heads, this motor will be very restrictive and the manifold boost will be high and really just at the higher rpms.

Likewise if the same motor had large valve and long duration and lift cam, the same pulley ratio on the above scenario would maybe only hit half the boost because the blower is not flowing enough air to build any head pressure in the motor, it breathes to well. You'll need to up the ratio quite a bit to get the same boost numbers as the overly restrictive first motor.

I know this is just bench racing and I'm only throwing this out to get you all thinking. The projected boost numbers come from somewhere, so there is some reliable data to give us a general information on what to set up ratio wise.

My 6:71 used a 1/2" Gilmore 3" timing belt. My ratio should have given me about 12:1 underdrive, but with my 6:71 being a street blower, it was not giving the same boost as a race prepped blower. My blower was clearanced an additional .010" at the rotor tips and had no Teflon rotor sealing inserts.

We never did do the boost gauge when running it on the dyno, but it did run REALLY well. It was gaining about 35 hp every 100 rpms near the 6k limit we set. With just shot peened stock rods, we limited the rpms to 6k and that was great with me. We had hit my corrected goal of 650 hp with 4 hp to spare @ 6k rpms. This motor still got me around 13 mpg, 30% O/D, and 4.11 9" crusing on the freeway at 70 mph.

You just cannot beat the jaw factor of a nice polished blower system. Even if in this case he only wants to get "some" added hp, the jaw factor will be an added byproduct.

I think this will be a great setup for him.
 

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Go for it!

Ajc5633 you're going to love the sound of that engine. I'm happy with mine, and you are going to turn heads. Some people think that there is not much power made but for street use believe me is great. Go for it!
 

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Discussion Starter #20
Ajc5633 you're going to love the sound of that engine. I'm happy with mine, and you are going to turn heads. Some people think that there is not much power made but for street use believe me is great. Go for it!
Really good to hear. I'm really just looking for a block now to start getting the machine work. I'm getting impatient but I guess that normal. Haha

I will look into heads once I actually have a block on my garage.


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