SpRaYd91Z28

My car is a 1991 Z28, with a 2k Stall, headers, flows. I run 13.9 on motor, and hope to dip into some mid to upper 12's on 125 shot of n20...just a few quick questions...Should I take out my superchip?? The person who owned the car before me ran the n20 with the chip and ran 12.8 with 100 shot. Or should I just take it out? And what is the ideal timing to set the motor at when running n20? What am I look'n at here guys?


Zach

IROCKZ4me

First you need to find the ideal total timing for your particular combo without N2O. Yes they are all different. Most cars make best power with total timing at WOT somewhere between 34° and 40° BTDC. Go to the strip and start making passes. Start at 34° and go up 2° at a time until the car slows. Then back up 1° at a time until you get the best Trap speed. That is your optimum total timing for your current setup. Often, but not always it will be around 36°to38° BTDC.
For nitrous you usually don't have to retard timing for the first 100 HP. After that 1° retard per 50hp total nitrous used is the norm.
up to 100 HP = no retard
150 HP = 3° retard
200 HP = 4° retard
250 HP = 5° retard

I would leave the chip alone and install a nitrous timing retard box.
That way you have the best power when not using nitrous and adjustable automatic retard when the system begins to spray.

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Tracy /AKA IROCKZ4me

• 355 cid
• AFR heads
• Arizona Speed & Marine hydraulic roller cam w/ AFR hydra-rev kit
• modified SLP runners
• TRW forged pistons/ceramic coated
• fully balanced
• Edelbrock headers/ceramic coated
• SLP cat-back
• Paxton supercharger
• Nitrous Express nitrous oxide

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