i know there is a thread about this but its old. im looking into doing this mod, anyone have an update on this? any reason why i shouldnt do it, i dont have warranty so i dont mind that and i dont mindthe decrease in mpg either.... thanks

 

did mine. butt dyno says.. pulls a lil stronger in mid range. always run 94oct.
actual proof of gains.. none. and it hasnt caused any problems

 

thanks man, but where i live i have never seen 94 oct i only see 91. i have see 102 oct i think but i only used that in my atv when i would go to the dunes. good to know u have not had any problems. i called my local dealers and one didnt know what i was talking about and the other wanted 210 bucks first then cut it down to 105 bucks so i said i would find somebody cheaper...

 

i wouldn't run 91 octane with stock timing, let alone advancing it 2*

As far as i know 91 octane is BARE MINIMUM with stock timing so it would probably detonate when it gets hot outside and you are running 91 octane on 2* advanced timing.

also, timing doesn't decrease your mpg. The decrease in mpg people get is due to them flooring it all the time because their butt dyno thinks the car gained 50hp (when it in fact probably got about 3-5 or even dropped in hp if it started to detonate).

 

so are you trying to say that it is a bad idea to do this mod, i live in southern cali and if im not mistaken we only have 3 grades of fuel where i live, 87,89,91

 

unless you have 93 octane i think it's a horrible idea.

Like i said, the oem timing is set for a minimum fuel of 91 octane so you're running the bare minimum on octane right now. Then you want to increase timing 2* which could easily lead to detonation. Each car is slightly different because no 2 engines rolling off the assembly line are exactly alike so maybe some have gotten by with it but i wouldn't chance it.

The gain is insignificant for what you are risking. If it was a possible 50hp gain then ya, maybe the risk is worth it if you don't mind rebuilding an engine but it's more like 5hp or less on an oem block with 91 octane fuel.

 

i did a little research but i guess there is nothing higher than 91 in california other than 100 oct racing fuel.

here's a link i found its old but the response from one of those guys is a good read..

http://www.smokinvette.com/corvettef...ad.php?p=20354

 

which does nothing but make the point that advancing timing on a poor fuel will help nothing.

for all those out there that say "hey, it won't detonate because the computer will pull timing". Ok, so computer first identifies knock to thus pull timing. That means knock had to occur first, so yes, you are still incurring damage because you have to have knock to detect it. Once it a while you get a knock no big deal, but if you have poor fuel and the car is continuously having to pull timing because it's knocking then you have lots of detonation damage as well as the fact that the car will pull more than that 2* of timing out so for adding 2* of timing you actually reduced your timing more because the ecu is trying to protect the engine from the unqualified person that tried to "tune it up".

so no, i wouldn't do it.

 

yup, it only makes ur point stronger that is why i showed it to u. so i agree with u and i will pass on this mod, my next mod will be a real tune instead, thanks man.

 

ya, you'll benefit more from just taking it to a tuner and having it customized for your car. Every engine is slightly different from the factory yet the tune is all the same so there is much room for improvement.

 

Why stop at 2? +4 degrees or go home.

 

****, i run 40* timing at 0psi of boost. If i blip the throttle really hard i can get 0.1psi