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I have never messed with a blower for an old school 350. I am a GenIII motor guy tell you anything you want to know, but when it comes to genI/II blowers i am lost.
What the hell do all the sizes mean. I am starting to gather parts for a SBC to make 600-700hp and i want to use a blower to make the power not the motor and i want it to run on 93.
So what do all the sizes mean and witch one will work best for me and why.
Justin
The 6-71 came from the old Detroit diesels. the 1st Number came from the number of cylinders ( IE 6,8... inline) The 71 came from the displacement of each cylinder. In this case 71ci.
Now that could be wrong, its just what I have been "told"...
The 6-71 came from the old Detroit diesels. the 1st Number came from the number of cylinders ( IE 6,8... inline) The 71 came from the displacement of each cylinder. In this case 71ci.
Now that could be wrong, its just what I have been "told"...
If it's a lie, they told me the same one...
I6-71 or 6I-71 Inline 6 cyl 71 is the displacement per cyl
Also used is the I8-71
You want the inline version of these blowers cause all the blower manifolds made are for this type. Mounting flange on the bottom of the case, and were mounted sideways on the Detroits.
The other type of blowers mounted /made for the v comfiguration ...6V-92's etc.. Detroits have no mounting flanges on the base of the blower housing.
They have 8 mounting bolts.1 in each four corners then 4 that go in the middle , they are a angled direction into the top of the block from mid height in the blower housing.
But I believe most gen-III's use whipples or some othe newer type design supercharger, more after market suppliers for the application.
bigger blowers 10-71 14-71 move more air and are generally a custom design case from their respective manufacturer (?)
I would post picts but can't seem to access my gallery
Hope this helps you get started
This is going on a old 350 and not on a genII motor. Well i guess we have a start.
This is going on a old 350 and not on a genII motor. Well i guess we have a start.
Then you would want a 6-71 or a 174 Weind
Run a larger blower at slower speeds, this will transfer less heat to the intake charge. I would run an 8-71 at lower speeds, spend the money on the blower and not on an intercooler. If you have a heavy boat, run a 6-71 with an intercooler. I would stay away from anything smaller than a 6-71. The "two lobe rotor" type roots superchargers, run too fast and get too hot. 5lbs. of boost from a '144' type blower is not the same as 5lbs of boost from an 8-71, on a small block Chevy motor. Heads, exhaust, and valve timing will also be important factors in your overall boost/breathing figures. Pump gas with iron heads = 5lbs, and aluminum heads = 7lbs of boost. (110/112 lobe center cams)
Run a larger blower at slower speeds, this will transfer less heat to the intake charge. I would run an 8-71 at lower speeds, spend the money on the blower and not on an intercooler. If you have a heavy boat, run a 6-71 with an intercooler. I would stay away from anything smaller than a 6-71. The "two lobe rotor" type roots superchargers, run too fast and get too hot. 5lbs. of boost from a '144' type blower is not the same as 5lbs of boost from an 8-71, on a small block Chevy motor. Heads, exhaust, and valve timing will also be important factors in your overall boost/breathing figures. Pump gas with iron heads = 5lbs, and aluminum heads = 7lbs of boost. (110/112 lobe center cams)
I was thinking of something like AFR race 227 heads with a 224/230 on a 114 lsa with 7 lbs of boost and if i have the exstra thousand (2) laying around i might put the intercooler on it.