I have just bought a heavily modded 2003 Evo With 11000 miles on it. It is tuned for race gas at sea level.

Will I need to seriously re-tune it for pump gas at 5500 feet (Albuquerque, NM) or will it run OK?

I have a tuner lined up to look at the car if need be and I am eager to learn about tuning it myself.

MODS:

Some upgrades: HKS 272/272cams, HKS adjustable gears, HKS Exhaust system, AEM EMS, AEM UEGO, Tein type S spring, Cusco type II front strut bar, Cusco carbon fiber rear strut bar, Greddy 720cc injectors, Greddy boost gauge, Greddy turbo timer, Exedy Hyper-Single racing clutch kit, Lancer Shop shift bushing kit, Lancer Shop clutch-line kit, Project Mu brake pads, BuchurRacing Big Front Mounted Intercooler, BuchurRacing Upper and Lower Intercooler pipes kit, small battery kit.

 

Yes! You will have to get it retuned or you WILL grenade your engine as soon as you hit boost. You will experience immediate knock and will quickly experience pre-detonation. You will blow holes in your pistons and melt your spark plugs. Race gas is much higher octane than normal pump gas. The octane is what keeps the gas from blowing up rather than burning quickly. Get your car retuned immediately or you will have very expensive repairs in your future.

strike

 

oh please dont ruin a nice car! have it retune asap!

 

Thanks, I will put race gas/pump gas mix in as the previous owner did until I get a tune. By the way he listed his HP numbers as 400 race gas, 350 pump gas. Are the pump gas figures just calulated or do you think that the guy was able to run pump gas? Also is the altitude going to hurt the tune?

 

turn the boost downtill u tune her

 

If I have a manual boost controller on the car will it help if I turn the boost down and if it is turned down is it safer to run 91 octane until I get it tuned?

 

actually, turning the boost down could be dangerous. someone else on this board grenaded their engine by turning down the boost on a highly tuned car. i am not sure which thread it was in but the tuner was turbo trix. apparently the air/fuel ratios were not tuned for lower boost and the car ran too lean.

my suggestion to you is that you should run race gas entirely until you can get it tuned properly. the higher altitude works to your advantage in that your air/fuel ratio will be richer which helps prevent knock/detonation.

seriously, your car likely has NO safety margins in order to get the most power out of it. you MUST get it retuned to accomodate your fuel and altitude.

strike

 

egl on doing it yourself

 

I have a tuner in mind to use. He just has to fit it in. I am going to learn as much as I can from him.

 

turning the boost down can be dangerous? ...u kidding? ... the more boost = higher chances of you damaging your motor...u turn down the boost a good amount...the safer things are. WHy do you think when something is wrong with the car the ecu puts your car into limp mode limiting boost drastically...it's a safety precaution...less boost = safer ...for him to blow his motor on say 10psi on regular gas is very very hard ...unless he redlines the isht out of hte car and just holds it at 9k ....

turn the boost down, read the gauge...if you gotta drive around at granny boost for a week, 2 weeks, 1 month...so be it... better than being without a car for a week, 2 weeks, 1 month ...etc

 

^^^^what he said, you not going to hurt the car by turning down the boost. More than likely the previous owner had two different .cal files saved, one for pump gas, and one for race fuel. He's an idiot if he sold it to you with the race gas settings loaded. Turn down your boost, and drive it very moderatly until you get a retune, and you should be fine. The aem should account for altitude if it's set up right, so the only real changes you should have to make will be a cause of a less controlable fuel (91 octane). Good luck, I hope you like doing a lot of research. It seems like you have much to learn before you can safely tune your own car. Just take it one step at a time.

 

read this thread:

https://www.evolutionm.net/forums/sh...&page=26&pp=15

it is 27 pages long, but i linked to a page that may make you think i might be on to something.

strike

 

On the page/pages you linked to, I think the post was trying to be sarcastic. i.e. that turning the boost down on that customer's car is not what caused the blow up. Hard to decipher through all the flaming.

 

read the whole thread. there is a point in there where it is finally determined that 4banga turning down the boost (which did not have proper fuel maps laid out for it at lower boost and no knock detection!) was what caused the engine to blow. the whole thread is valuable to read, but it is tedious if you have already read the whole thing (like i have). this is why i linked to the first reference that i found for the conclusion. really, just don't mess with it until you can log it and have det cans at hand. run race gas and do not turn down the boost until it is retuned. this is what i would do if it were my car. you can choose to do whatever you want though as it is your car and your money. regardless, good luck and enjoy your car. it is awesome!

strike

 

it will definatley need to be tuned before you boost the car with pump gas.......