Rough Boost Numbers - Novi 2000 on a 302/351
Since everyone always wants to know how much boost different pullies will make most commonly for 302/351 based motors I figure we can start a tally of different setups so that people can get rough ideas of how much boost they might see. Remember you can't directly compare these numbers as each motor is different but you can get a basic idea from these. I've collected these from what people have posted in this forum and on corral. If anyone wants to correct or add to this feel free I'll add it to the first post here. I'm assuming most of these people have atleast a 2.5 inch exhaust system but I can't track down all of the setups. You can use the ratios to see what a cog would be to a similar serpentine ribbed setup and vise versa.
Crank/Blower = Ratio = PSI @ RPM / Cubes / Mods if any / Impeller RPM
Cogged
73/29 = 2.51 = XX# @ 7000 rpm 370 heads/cam/intake 62377 (Impeller was Destroyed)
73/31 = 2.35 = 17# @ 5800 rpm 306 heads/cam/intake 48350
73/34 = 2.14 = 20# @ 6800 rpm 308 heads/cam/intake 51684
72/31 = 2.32 = 15# @ 6000 rpm 347 heads/cam/intake 49332
68/34 = 2.00 = 15# @ 7000 rpm 347 heads/cam/intake 49560
Serpentine
8.00/3.00 = 2.66 = XXXX @ 6500 rpm 370 heads/cam/intake 61360 (8 rib belt slip)
8.00/3.00 = 2.66 = 13#'s @ 5900 rpm 396 heads/cam/intake 55696 (A/A intercooler)
8.00/3.00 = 2.66 = 15#'s @ 5800 rpm 351 heads/intake 54752 (A/A intercooler (Powerstroke))
8.25/3.40 = 2.42 = 14#'s @ 6000 rpm 393 heads/cam/intake 51538 (A/A intercooler) 641rwhp
8.00/3.25 = 2.46 = 30#'s @ 7200 rpm 306 heads/cam/intake 62740
8.00/3.25 = 2.46 = 23#'s @ 6800 rpm 357 heads/cam/intake 59254
8.00/3.75 = 2.13 = 20#'s @ 6000 rpm 306 heads/cam/intake 44800 (8:1 comp)
7.75/2.75 = 2.82 = 20#'s @ 6200 rpm 306 heads/cam/intake 61853
7.40/3.75 = 1.97 = 12#'s @ 6300 rpm 393 heads/cam/intake 43512 605rwhp
7.40/3.20 = 2.31 = 15#'s @ 6300 rpm 393 heads/cam/intake 50990
7.40/3.20 = 2.31 = 12#'s @ 6300 rpm 393 heads/cam/intake 50990 (A/W intercooler) 650rwhp
8.50/3.20 = 2.65 = 10#'s @ 4500 rpm 393 heads/cam/intake 41835 (A/W intercooled) belt slip
7.00/2.95 = 2.37 = 18#'s @ 5600 rpm 302 stock 47040
7.00/3.00 = 2.33 = 16#'s @ 6000 rpm 302 heads/cam/intake 48639
7.00/3.00 = 2.33 = 14#'s @ 6200 rpm 331 heads/cam/intake 51212
7.00/3.00 = 2.33 = 13#'s @ 5800 rpm 331 heads/cam/intake 47908
7.00/3.10 = 2.25 = 19#'s @ 6300 rpm 302 heads/cam/intake 50359
7.75/3.60 = 2.15 = 13#'s @ 6500 rpm 393 heads/cam/intake 48976
7.00/3.25 = 2.15 = 16#'s @ 6250 rpm 306 heads/cam/intake 47654
7.00/3.25 = 2.15 = 10#'s @ 5500 rpm 347 heads/cam/intake 41935
7.00/3.50 = 2.00 = 12#'s @ 5900 rpm 306 heads/cam/intake 41300
7.00/3.50 = 2.00 = 11#'s @ 6300 rpm 302 heads/cam/intake 44604
7.00/3.50 = 2.00 = 12#'s @ 6200 rpm 302 stock 43896
7.00/3.50 = 2.00 = 12#'s @ 6000 rpm 302 heads/cam/intake (8 rib)
7.00/3.50 = 2.00 = 10#'s @ 6000 rpm 302 stock 42480
7.00/3.50 = 2.00 = 10#'s @ 5700 rpm 302 cam/intake 40356
7.00/3.50 = 2.00 = 9#'s @ 6500 rpm 347 heads/cam/intake 46020
7.00/3.75 = 1.86 = 8#'s @ 5500 rpm 302 cam/intake 36344
Lastly remember Paxton recommends a maximum 55,000 impeller speed. You can calculate the impeller speeds with these pulley combinations using the formula below. There are combinations in here which do spin the impeller faster than the maximum impeller speed, which is obviously not recommended. Neither the contributors or myself shall be held liable for any damage resulting from using any of the submitted pulley combinations.
(Crank pulley / Blower pulley) X 3.54 or (3.50 newer N2K) X ENGINE RPM = IMPELLER SPEED
Note: The 3.54/3.50 represents the Novi2k's internal gear step up ratio. If you have a newer Novi2k you have a 3.50 step up ratio
