i know the idea behind what a supercharger does and how it works but thats it. i drove a Mini with a supercharged motor and a 6spd and it was crazy fast. ive always wanted to build a car with a blower so nows my chance.right now i have a stock 307 in my 83 cutlass supreme 2dr but i am looking for a olds 350. any advice will be usefull. thanks.

 

A properly built blown SBO is going to run around $10,000 plus upgrades to the rest of the car to hangle it. I looked into one of the Weiand "street" blowers like the 144, but it is [pretty expensive for the performance gains. I also REALLY wanted a blown 350 Olds, but I just could not make the numbers work.

 

im gonna keep lookin and puttin money away. the hardest part really is findin a blower for a single 4bbl holley carb. everyone i see is for dual 4bbls.

 

on a Roots style blower you interchange blower tops so you can run a single four, dual fours, six two's or whatever you want. Simple and inexpensive...

Google "blower top plates" and "blower carb plates"....

 

Are you just looking to do a small blower or something like a 6/71? Pretty well any engine with a blower should be built with that in mind (compression, cam, etc.). If you are going with a larger blower, you will have to go with 2 4 bbls just because of the air you are forcing down there.

 

I have an 850 Carter AFB for my blown Hemi... you don't need dual carbs unless you are looking for big HP numbers at high rpm's.... my Hemi will never see 5,000 rpm's 'cuz I'm old and I hate breaking stuff...

That said, I also have a 4X2 set-up but it uses Stromberg 97's that are only 175 cfm each.

 

Blowers make more power for any given engine by forcing more air and fuel into the cylinders, superchargers are driven by a pulley from the crankshaft, turbochargers by exhaust pressure.

In both cases unless the crank, rods and pistons are strengthened to cope with the extra power the engine won't last long, normally a lower cr is required and the job is done by low compression pistons strong enough to deal with the power output.
But the heads need to be able to flow the higher volume that supercharging will produce and 307s don't have good gas flow, it's designed to meet '80s emissions requirements.
A 350 is a better starting point, but it will cost a good bit of money to work reliabley with a blower as has been said, and the transmission will also need upgrading, the cooling system will need to be able to cope with the extra heat a blower will make, more power = more heat - it's the laws of physics, and a trans cooler is another must.

Doing it right won't come cheap, but not doing it right will cost lots more in the long term. Good luck!.

Roger.

 

You can run a few pounds of boost without too much problem, but the light main webs and four head bolts per cylinder will cause problems with high boost. Look at the Cummins engine in Dodge pickups to see the extreme they went to: 6 head bolts per cylinder at 120 ft lb not 80, rods that weigh 1900 g vs. 700-900 Olds; pistons and pins that weigh several times what Olds stuff weighs, etc. Of course you can run 35-50 psi boost with a Cummins stock engine.

In summary, you are probably best served by the pathways to power that are well known and the Olds community can offer suggestions. You can get the kind of performance you are seeking with a normally aspirated 350 or 455, and it will live for years.