[mr.squatch]

Ok, building a new motor, old one went boom. Here's my dilema. I'm going at least 10.5:1 compression, possibly 11:1, what should my optimal timing be? I'm getting a custom chip, this is why I need to know. If it is advanced a bit, how will this affect my flipside timing for nitrous? Like for example, if I should run 2 degrees of advance n/a to run best, but then want to drop 100 shot or even 150, I should be at 2-3 degrees retard. Should I build a flipchip this way? with potentially 5 degrees of timing difference between flips, or do they kinda cancel eachother out, like +2 na and then 0 for nitrous. I dunno if this is making any sense. Opinions please. thx

g

 

[ILfocus]

what are you going to do about fuel psi with the 100 shot or 150 shot? You are suppose to retard aprox. 1 degree for every 50 shot of nitrous. So if you are running a 150 shot you will need to retard the timing at least 3 degrees.
So on your flip chip you will have it advanced 2 degrees for na driving and retarded 2-4 for your shot.

I am running stock timing when na (10.5:1 c/r) and then i retard 2 degrees when spraying the 75 shot.

I havent tried to run na with advanced timing but i bet it would help me out alot.
Are you going to get 11:1 pistons or 10.5:1 pistons and mill the head down?

Good luck

 

[mr.squatch]

the 50hp/degree was what I was going with, I just needed to know whether to retard 2-3 degrees from zero or from the advanced setting. I think you answered my ?. I'm going with 10.5:1 pistons and considering decking the head. I have to check out the head first to see if there was any damage from the kaboom before I decide. Thanks for the help.


Another ?, if you run 10.5:1 or even 11:1 I think it's possible to run on 91 during regular driving. If you advance the timing does that make this not so? I have to daily drive this thing so I want to cover all the bases. Input please. Thanks

g

 

[ILfocus]

I run the highest octain avail, norm 93 oct. or there is a place in town (BP) that has 93.5 min oct.

I always run that because i never know when i am going to spray. If you advance your timing any you should always run the higher oct.

Good luck.

Btw what caused the "kaboom" as you put it?

 

[boostenzx3]

the nawwwssssss caused the booooom

 

[mr.squatch]

yeah, i'll always run 91 at least, 93 is not readily available in my town. I know when I'm gonna spray, and have a drum of 111 in the garage for just such occasions. The cause of the kaboom was dumass driver decision. impromptu streetracing challenge from a scooby + not being prepared = spraying on 89 octane = 3 one dollar sparkplug and one 1000 dollar one. Lesson learned, I knew better, it did what it should have done and I should have known. Still beat the scoob on 3 cyls tho.

Thanks for the info. I'm pretty sure I'll order my chip with 2-3 degrees of advance, and 1 degree of retard on the flip, and stick with the 100 shot for a while til i can get a feel for what the timing's doing. I don't wanna go thru this again.

Thanks doods

g