Yamablue
Member
I have a set of 8BU00s that have been sitting around for a while and I have been doing some research on them. I ran a radar run this weekend and ran a 94 in the 1000' and I would have thought it would run better than that. Temps were about 13*F and don't know the pressure (950ft). I have HH weights in there right now that are suppose to be the 48gr base, but my gram scale says 43.3gr. There is an untapped hole between the mid and tips weights adjustment holes so I don’t know if the guy who had them before me lightened them up. I ran the black 150/300 spring and had about 5000 engagement. Helix used was a Dalton 52R46 which should be mostly like a straight 46 and a green spring at 70. Shift RPM from 0-50 is about 8700 RPM and climbing to 9200 after that. 1 1/4 track with 192 studs.
Years ago I ran the 8BUs with my ported setup and the thing had some amazing pull down low, but can’t remember anything about them. It seems most of the setups on here are for SRXs with 8500rpm max. What spring, roller, rivet combo can I use to get the proper 9100 shift RPM? I have the stock 14.5mm and 15.6mm rollers along with a smorgasbord of springs. Helixes are 45/38, 48/40, 46/40, 51/43, 52R46 and most of the Yamaha secondary springs. If anyone can point me in the right direction, that would be great. Keep in mind, this is only my radar run setup, I am going to keep my HH for the trail. What are the other CPR vipers running for MPH in the 1000ft on ice?
Years ago I ran the 8BUs with my ported setup and the thing had some amazing pull down low, but can’t remember anything about them. It seems most of the setups on here are for SRXs with 8500rpm max. What spring, roller, rivet combo can I use to get the proper 9100 shift RPM? I have the stock 14.5mm and 15.6mm rollers along with a smorgasbord of springs. Helixes are 45/38, 48/40, 46/40, 51/43, 52R46 and most of the Yamaha secondary springs. If anyone can point me in the right direction, that would be great. Keep in mind, this is only my radar run setup, I am going to keep my HH for the trail. What are the other CPR vipers running for MPH in the 1000ft on ice?
mopar1rules
Active member
i don't know if you can get 9000 rpm w/stock 14.5mm rollers, w/the 8bu-00's. you'll probably need 15.6mm rollers, hauck orange primary spring (55/136), 48/40 helix, yamaha red spring @ 80deg, and no rivets in weights. my guess is 9000-9200 rpm.
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Yamablue
Member
OK to be more specific on the weights I have: 89A-10, 8BU-00, 8EK-00, Dalton 57.5 lightened to 51-52 gr, and the HH 48 but actually 43gr. 48/40, 46/40, 40/35, 47, 52R46. Various 40 and 45kg yami primary springs, HH black, bender yellow, dalton Blk/Blu and whatever factory yami sec springs.
mopar1rules
Active member
so, your looking for a better setup, using only the components that you currently have in your parts bin??
Yamablue
Member
I'd like to use the 8BUs but I just figured I'd mention the other stuff I have in the event the other weights I have would be a better base for 1000ft.