[ChiefCrazyCanuck]

I am wondering about other peoples experiences with the KB Hypereutectic in Pontiac mills? I am currently running a set in my 455 with good results so far. I would also like to run a little nitrous(150 HP) but have heard from some that this may be a lesson in destruction.However, I know of many people that push these pistons very hard. In one instance,a friend ran a 11.5:1 cr,175 nitrous fed 360cid sbchev(10.7 et)with no ill effects. In my own case, I have a 600+ hp BBC in my 71 Chev p/u with KB's at 10:1 compression(92 octane) with cast iron Merlins and again,no problem. I am thinking that failures people encounter with these pistons are the result of other problems, such as lean mixtures and over advanced timing. So would any of you feel safe to use nitrous with these pistons, assuming detonation is not a factor? Thanks.

[ChiefCrazyCanuck]

I am wondering about other peoples experiences with the KB Hypereutectic in Pontiac mills? I am currently running a set in my 455 with good results so far. I would also like to run a little nitrous(150 HP) but have heard from some that this may be a lesson in destruction.However, I know of many people that push these pistons very hard. In one instance,a friend ran a 11.5:1 cr,175 nitrous fed 360cid sbchev(10.7 et)with no ill effects. In my own case, I have a 600+ hp BBC in my 71 Chev p/u with KB's at 10:1 compression(92 octane) with cast iron Merlins and again,no problem. I am thinking that failures people encounter with these pistons are the result of other problems, such as lean mixtures and over advanced timing. So would any of you feel safe to use nitrous with these pistons, assuming detonation is not a factor? Thanks.

[PONTIAC DUDE]

Before ya spray. Go my website and read the info. Will save you a lot of heartaches.

You can run any piston and Nitrous........ to a limit.

Build it fast, build it right, build a Pontiac.

http://PontiacDude.cc

[Ken -Ace- Brewer]

The K.B. Pistons are good and strong. We have guys out there running 10's with them!
As far as Nitrous? I believe you should have gapped the rings for it. But to be honest, Dude is the man when it comes to Nitrous He would know better than I.
Be Cool,

ACE-P.P.R.

http://pacificperformanceracing.com

[ChiefCrazyCanuck]

Thanks for the info Ace and Dude.P-Dude,the info that you have in that site is great!I never knew how much good stuff you have in there.I will for sure use those tuning tips when I get back home to tune my bird to a hopefully new level of speed.Hey, mine's a full weight 76T/A too,although nowhere near as rapid as yours.I have a digital 6 box(4 th one!!!!!)so I can use the N2O retard to keep me safe and will hook up another line and seperate blue pump for the nitrous.I will sump the tank and run braided fuel lines to get rid of any possible bottlenecks.Do you feel 175 hp nitrous is safe with 92 octane and ample fuel supply w/4 degrees ignition retard(30 total). Or is race fuel pretty much a given at this level of performance greed.Thanks for your help.I'm hoping for a 10 second slip.

[ChiefCrazyCanuck]

BTW Dude,the ring gap was set up in anticipation of some moderate nitrous use.Thanks.

[PONTIAC DUDE]

Nah, pump gas and 175 is OK. But I would pull at least 6 out to start if your under 10-1 compression and read plugs, Better to be safe.
If your over that then race gas for sure or a lot of retard.

The deal is that with race gas you'll go faster with less retard then retarding the heck out of it to reduce detonation with pump gas.

I just like the seperate fuel system and race gas. The lead with NOS really helps.

Build it fast, build it right, build a Pontiac.

http://PontiacDude.cc

[ChiefCrazyCanuck]

Thanks Dude! That is the kind of info I really need.Maybe if I want to make some stronger passes I will just eliminate or limit to two degrees the spark retard when running race fuel.It is just an almost 10:1 motor,but better to err on the side of safety to keep her together.When I build the motor for my 68Bird over this winter I will be callin' on you for parts,as I want to build a super nasty pump gas 455 for it.I have a short block already,but it will need some going through and some specific pieces to help it survive the rigors of racing.