Sorry to hear your having Buick Nitrous "issues" Dave.. Great info. Kevin and I like background on that plug pic! Gary G.
What would you like to know Gary. That's on vpn20 fuel ngk 10.Bbc 23 deg.26 deg head rolled to 23.Compression was 15-1.It liked 38.5 deg on motor.That run it was 17 deg.total. Cut apart it had a light grey ring fuel ring at the base of the porcelain. You will never get a plug to look like that on c16 or c23.Those fuels are very heavy specific gravity wise.The heavier the fuel the less it likes to atomize.I like fuels under .700 spec gravity for Nitrous.I really like c25 but it is more sensitive.For turbo and blower deals heavy fuels don't matter.For nitrous you have to have complete atomization to keep it happy.For turbo guys on gas I can tell you without a shadow of a doubt.NEVER I MEAN NEVER run c25 in a turbo engine.It will kill itself fast but that's another thread.
What changes are you going to make? Are vacume pumps more for dry sump oiling? Ive always wondered if a vac pump can actually keep up with a motor at high rpm. Also are u using nitrous injectors or a fogger/ spray plate under the carb?
To get the most out of a vacuum pump the motor needs to be set up to run one to achieve the big gains.The big thing here is low tension rings.Some guys will run more wrist pin clearance in order to keep them happy.Na motors a proper sized vacuum pump will keep up down track.A nitrous motor will loose around 2 in/hg when the kit is on.A turbo motor the vacuum pump struggles.Our 400 cid motor with a moroso pro mod pump loses 5-7 in/hg by the stripe.A vacuum pump will lower oil pressure depending on the amount of vacuum you run.We pull alot of vacuum at 18in/hg we loose 10 psi of oil pressure.Now this is still a wet sump deal.Dry sump will not be affected as much.I can't say how much I haven't run one yet.This year I will have that data.
