All About Turbochargers – Part 8: Nitrous, E85, and Turbos

We are seeing this used more and more in gasoline-burning engines, but why do turbos and E85 mix so well? And how about nitrous? Can’t we still use it with our turbo?

Let’s talk first about nitrous use on your turbocharged Jeep. Yes, it can be done and can be put to some really good use. If you’re using a turbo that takes some time to spool, using nitrous can help make up for some lost time by spraying until your turbo Jeep hits boost. Many nitrous kits feature a boost cut that will stop the flow of nitrous oxide once it hits your boost target.

If you’re using an air-to-air intercooler, you could use the cooler nitrous oxide spray to chill it while you stage at a drag strip. Nitrous use isn’t eliminated with a turbo, but you’ll have to get creative in use and far more careful with your tune.

E85 and turbos can make some really amazing results. It’s not unusual to see gains made when you switch from race gas to E85. This is thanks to its cooler burn temperature and its higher knock resistance (octane). This allows you to use more boost than when using some race gas mixes.

So, while E85 isn’t terribly efficient in a naturally aspirated car, a turbo car makes far more use of the corn-based fuel.

However, you will need to increase your BFSC (for your turbo size calculation) and increase your injector sizes to compensate for the lower BTU energy of E85. You’ll also need to keep in mind that your O₂ readings will be leaner with E85 … although that does not necessarily mean you are running an insufficient amount of fuel, consult with an E85 tuner in your area just to be sure.

That’s it for now, but let us know what you think and we’ll see about doing more.