I was just going through a magazine and came across an ad for Excessive Motorsports. They had NX kits and I started looking at them, and they list the qualities of the kit, one of which said "No timing retard needed." I was just wondering if someone could clarify this for me, why it doesn't need timing retard, and if it would be a could idea to retard anyway, just to be safe? Thanks a lot.

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'89 Camaro RS 6cyl. auto, don't know how much longer I'll have it.
'90 Iroc TPI 305, 5 spd B&M Ripper shifter, hopefully I can rob a bank or something and get more
www.geocities.com/irocnroll90

 

you'll get the most out of the car if you retard a couple degrees. This was, all the fuel is has time to burn.

 

You are best off investing in some kind of scan tool, monitoring your nitrous runs, and retarding as needed.

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1989 IROC-Z 5.7L
NOS 150HP kit
ProBuilt 700R4, PI Vigilante 2800 stall lockup
Baer Brakes 12" Sport System

 

NOS doesnt make any reccomendations to retard your timing when using their kits

 

NO timing retard probably isn't quite as likely as not as much or no retard needed in most cases.

The biggest reason for timing retard when using nitrous is not so much for giving it more time to burn. In fact it is more like the exact opposite.
A nitrous enhanced mix burns faster than a natural one. Therefor you don't need as much timing advance when using nitrous. It is possible that the mix can burn so much faster that too much cylinder pressure occurs before the piston reaches top dead center.
This isn't too important with smaller shots (less than 150 HP) anyway.

The second reason is, an engine with a better atomized and distributed mix can run more advance with less fear of detonation. Nitrous systems of the past have not always been great as far as distribution goes.

Also there could be other problems with the engine that could contribute to detonation and when on nitrous detonation can be an engine killer more so than normally.
There are also plenty of people running too much timing already.

So to say a kit never ever needs timing retard might be a stretch. But a well designed kit with relatively small power levels + careful tuning = little or no needed retard.

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Tracy /AKA IROCKZ4me
'86 IROC-Z Camaro
"Cogito ergo zoom"

• 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

EFI Performance Club on Yahoo

[This message has been edited by IROCKZ4me (edited June 23, 2001).]