SuperChargers on a 302

k0rupt3d · 03-10-2009

Im looking to run the biggest super i can put on my 302. I just want to know if stroking my motor to a 331 or a 347 would produce more HP/Tq then just boring it over to a 306?

RemRem123 · 03-10-2009

the bigger the displacement the more power you make, the 331 and 347 are very torquey, good street engines, but if you put on a blower, make sure you have a forged rotating assembly and the correct gaskets, and very good heads to let it breath

jspagna1 · 03-10-2009

Make sure you take into account your compression ratio when running a Supercharger.

k0rupt3d · 03-10-2009

Quote:

Originally Posted by RemRem123

the bigger the displacement the more power you make, the 331 and 347 are very torquey, good street engines, but if you put on a blower, make sure you have a forged rotating assembly and the correct gaskets, and very good heads to let it breath

Of course ill be running all forged internals and some 225cc AFR heads.
What compression ratio should i be running for a super?

jspagna1 · 03-10-2009

A safe range is anywhere from 8.5:1 - 9.5:1, a conservative number would be 9.2:1. It also depends on how much boost? A safe range for boost would be 5-8 lbs of boost. These are very conservative numbers and many may not agree with me?

k0rupt3d · 03-10-2009

Quote:

Originally Posted by jspagna1

A safe range is anywhere from 8.5:1 - 9.5:1, a conservative number would be 9.2:1. It also depends on how much boost? A safe range for boost would be 5-8 lbs of boost. These are very conservative numbers and many may not agree with me?

Yea sounds about right to me. Ill prob stay around the min 5lbs im running it on a old 289 block.

And About my old 289 block i want to put in a Coast high performance 347 stoker kit. can i go that big from a 40 yr old 289 block I believe is a C code ?

After building the motor and running it for a while i plan to swap the parts on to a man o war aluminum block

soccer1061287 · 03-10-2009

With that kit, I am almost positive that you will have to clearance the block for the rods. That is a fancy way of saying you will need to grind the cylinder skirts so that the rods don't hit them. At least I did on my stroker for a windsor. Just my 2 cents worth on boost and compression, I was running a 9:1 motor with all forged dynamic assy and I would reach 15-17 pounds at around 6,000 rpm. And I shot that engine with 100 hp of nitrous as well. Not a good combination for a daily driver when the driver has a lead foot.

jspagna1 · 03-11-2009

Quote:

Originally Posted by soccer1061287

With that kit, I am almost positive that you will have to clearance the block for the rods. That is a fancy way of saying you will need to grind the cylinder skirts so that the rods don't hit them. At least I did on my stroker for a windsor. Just my 2 cents worth on boost and compression, I was running a 9:1 motor with all forged dynamic assy and I would reach 15-17 pounds at around 6,000 rpm. And I shot that engine with 100 hp of nitrous as well. Not a good combination for a daily driver when the driver has a lead foot.

soccer1061287 is right you will have to have work done to the block. And like I said my numbers are very conservative.
I must be showing my age?
It's all up to you how much is enough for you. And I am not one for nitrous (age thing again). A motor can only take so much abuse.
But again that is only my opionion.

k0rupt3d · 03-11-2009

Thanks for ur help guys very helpfull info
after researching iv desided to run a 331 for higher RPM and tq then the 347