anyone ever spray into your sn?

[87tpita]

My 385 sbc build is almost ready to fire but I have 2 questions.

1.) Will the sn92 be a bottle neck for a stroked 350 since it will only flow 750cfm?

2.) My current pulley setup puts my sn at 39k rpm at 4900rpm. I really like the way the boost comes on early in the powerband for everyday driving allthough I need to shift a 5600rpm when Im at the track. Could I shoot a 50 or 75 shot into my intake about 18" before the paxton to cool it and the air charge down to allow me the extra time to get to 5600rpms?

[444]

39k @4900 = 45k @5600. 45K is high, maybe doable with a good external oil cooling system. You will be beyond the efficiency peak of the unit though.

[87tpita]

That is why I wanted to spray it with a small shot to cool the hot air that would be coming out after the recommended 39k rpm.

[444]

I understand that, but IMO you would be best off if you cooled the oil as well. N2O is pretty cold, but won't cool the oil. If you do both I think that would be a big help, plus you want the oil cooled if you want your balls/races to live at that rpm.

[87tpita]

Im going to get the oil cooler eventually and spray a little shot into it. Ive been worried about the heat created over 39k but I didnt consider that my 6rib belt is probally slipping and from what Ive read its usally around 10% after 4500rpm anyway. That eases my mind a little bit.


As for my first Q Ive read a healthy 383 can pull up to 1000cfm naturally aspirated,,,, will the sn92 be hurting me on the top end since it will only push 750cfm ? Thanks for the info:teeth:

[444]

No 383 is pulling 1000cfm at 5600rpm. At 8000rpm+ maybe.

[87tpita]

Thanks for that info,,, Ive been worried if I could use the sn92 at all. :teeth:

[jlmccuan]

What do you suppose the chances are that the 40K impeller speed is directly related to the input shaft bearing maximum rated RPM of 10K ? Coincidence?